Sample records for air sampling results

  1. Inertial impaction air sampling device

    DOEpatents

    Dewhurst, Katharine H.

    1990-01-01

    An inertial impactor to be used in an air sampling device for collection of respirable size particles in ambient air which may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry.

  2. Inertial impaction air sampling device

    DOEpatents

    Dewhurst, K.H.

    1990-05-22

    An inertial impactor is designed which is to be used in an air sampling device for collection of respirable size particles in ambient air. The device may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry. 3 figs.

  3. Inertial impaction air sampling device

    DOEpatents

    Dewhurst, K.H.

    1987-12-10

    An inertial impactor to be used in an air sampling device for collection of respirable size particles in ambient air which may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry. 3 figs.

  4. Air sampling results in relation to extent of fungal colonization of building materials in some water-damaged buildings.

    PubMed

    Miller, J D; Haisley, P D; Reinhardt, J H

    2000-09-01

    We studied the extent and nature of fungal colonization of building materials in 58 naturally ventilated apartments that had suffered various kinds of water damage in relation to air sampling done before the physical inspections. The results of air samples from each apartment were compared by rank order of species with pooled data from outdoor air. Approximately 90% of the apartments that had significant amounts of fungi in wall cavities were identified by air sampling. There was no difference in the average fungal colony forming unit values per m3 between the 15 apartments with the most fungal contamination and the 15 with the least. In contrast, the prevalence of samples with fungal species significantly different than the pooled outdoor air between the more contaminated versus the less contaminated apartments was approximately 10-fold. We provide information on methods to document fungal contamination in buildings.

  5. Microbial Air and Surface Monitoring Results from International Space Station Samples

    NASA Technical Reports Server (NTRS)

    Ott, C. Mark; Bruce, Rebekah J.; Castro, Victoria A.; Novikova, Natalia D.; Pierson, D. L.

    2005-01-01

    Over the course of long-duration spaceflight, spacecraft develop a microbial ecology that directly interacts with the crew of the vehicle. While most microorganisms are harmless or beneficial to the inhabitants of the vehicle, the presence of medically significant organisms appearing in this semi-closed environment could adversely affect crew health and performance. The risk of exposure of the crew to medically significant organisms during a mission is estimated using information gathered during nominal and contingency environmental monitoring. Analysis of the air and surface microbiota in the habitable compartments of the International Space Station (ISS) over the last four years indicate a high presence of Staphylococcus species reflecting the human inhabitants of the vehicle. Generally, air and surface microbial concentrations are below system design specifications, suggesting a lower risk of contact infection or biodegradation. An evaluation of sample frequency indicates a decrease in the identification of new species, suggesting a lower potential for unknown microorganisms to be identified. However, the opportunistic pathogen, Staphylococcus aureus, has been identified in 3 of the last 5 air samples and 5 of the last 9 surface samples. In addition, 47% of the coagulase negative Staphylococcus species that were isolated from the crew, ISS, and its hardware were found to be methicillin resistance. In combination, these observations suggest the potential of methicillin resistant infectious agents over time.

  6. Air sampling workshop: October 24-25, 1978

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1979-06-01

    A two-day workshop was held in October 1978 on air sampling strategies for the occupational environment. Strategies comprise the elements of implementing an air sampling program including deciding on the extent of sampling, selecting appropriate types of measurement, placing sampling instruments properly, and interpreting sample results correctly. All of these elements are vital in the reliable assessment of occupational exposures yet their coverage in the industrial hygiene literature is meager. Although keyed to a few introductory topics, the agenda was sufficiently informal to accommodate extemporaneous discussion on any subject related to sampling strategies. Questions raised during the workshop mirror themore » status of air sampling strategy as much as the factual information that was presented. It may be concluded from the discussion and questions that air sampling strategy is an elementary state and urgently needs concerted attention from the industrial hygiene profession.« less

  7. Cast Stone Oxidation Front Evaluation: Preliminary Results For Samples Exposed To Moist Air

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Langton, C. A.; Almond, P. M.

    The rate of oxidation is important to the long-term performance of reducing salt waste forms because the solubility of some contaminants, e.g., technetium, is a function of oxidation state. TcO{sub 4}{sup -} in the salt solution is reduced to Tc(IV) and has been shown to react with ingredients in the waste form to precipitate low solubility sulfide and/or oxide phases. Upon exposure to oxygen, the compounds containing Tc(IV) oxidize to the pertechnetate ion, Tc(VII)O{sub 4}{sup -}, which is very soluble. Consequently the rate of technetium oxidation front advancement into a monolith and the technetium leaching profile as a function ofmore » depth from an exposed surface are important to waste form performance and ground water concentration predictions. An approach for measuring contaminant oxidation rate (effective contaminant specific oxidation rate) based on leaching of select contaminants of concern is described in this report. In addition, the relationship between reduction capacity and contaminant oxidation is addressed. Chromate (Cr(VI) was used as a non-radioactive surrogate for pertechnetate, Tc(VII), in Cast Stone samples prepared with 5 M Simulant. Cast Stone spiked with pertechnetate was also prepared and tested. Depth discrete subsamples spiked with Cr were cut from Cast Stone exposed to Savannah River Site (SRS) outdoor ambient temperature fluctuations and moist air. Depth discrete subsamples spiked with Tc-99 were cut from Cast Stone exposed to laboratory ambient temperature fluctuations and moist air. Similar conditions are expected to be encountered in the Cast Stone curing container. The leachability of Cr and Tc-99 and the reduction capacities, measured by the Angus-Glasser method, were determined for each subsample as a function of depth from the exposed surface. The results obtained to date were focused on continued method development and are preliminary and apply to the sample composition and curing / exposure conditions described in this

  8. 3D Air Quality and the Clean Air Interstate Rule: Lagrangian Sampling of CMAQ Model Results to Aid Regional Accountability Metrics

    NASA Technical Reports Server (NTRS)

    Fairlie, T. D.; Szykman, Jim; Pierce, Robert B.; Gilliland, A. B.; Engel-Cox, Jill; Weber, Stephanie; Kittaka, Chieko; Al-Saadi, Jassim A.; Scheffe, Rich; Dimmick, Fred; hide

    2008-01-01

    The Clean Air Interstate Rule (CAIR) is expected to reduce transport of air pollutants (e.g. fine sulfate particles) in nonattainment areas in the Eastern United States. CAIR highlights the need for an integrated air quality observational and modeling system to understand sulfate as it moves in multiple dimensions, both spatially and temporally. Here, we demonstrate how results from an air quality model can be combined with a 3d monitoring network to provide decision makers with a tool to help quantify the impact of CAIR reductions in SO2 emissions on regional transport contributions to sulfate concentrations at surface monitors in the Baltimore, MD area, and help improve decision making for strategic implementation plans (SIPs). We sample results from the Community Multiscale Air Quality (CMAQ) model using ensemble back trajectories computed with the NASA Langley Research Center trajectory model to provide Lagrangian time series and vertical profile information, that can be compared with NASA satellite (MODIS), EPA surface, and lidar measurements. Results are used to assess the regional transport contribution to surface SO4 measurements in the Baltimore MSA, and to characterize the dominant source regions for low, medium, and high SO4 episodes.

  9. Air sampling with solid phase microextraction

    NASA Astrophysics Data System (ADS)

    Martos, Perry Anthony

    . With 300 seconds sampling, the formaldehyde detection limit was 2.1 ppbv, better than any other 5 minute sampling device for formaldehyde. The first-order rate constant for product formation was used to quantify formaldehyde concentrations without a calibration curve. This spot sampler was used to sample the headspace of hair gel, particle board, plant material and coffee grounds for formaldehyde, and other carbonyl compounds, with extremely promising results. The SPME sampling devices were also used for time- weighted average sampling (30 minutes to 16 hours). Finally, the four new SPME air sampling methods were field tested with side-by-side comparisons to standard air sampling methods, showing a tremendous use of SPME as an air sampler.

  10. A new analysis system for whole air sampling: description and results from 2013 SENEX

    NASA Astrophysics Data System (ADS)

    Lerner, B. M.; Gilman, J.; Dumas, M.; Hughes, D.; Jaksich, A.; Hatch, C. D.; Graus, M.; Warneke, C.; Apel, E. C.; Hornbrook, R. S.; Holloway, J. S.; De Gouw, J. A.

    2014-12-01

    Accurate measurement of volatile organic compounds (VOCs) in the troposphere is critical for the understanding of emissions and physical and chemical processes that can impact both air quality and climate. Airborne VOC measurements have proven especially challenging due to the requirement of both high sensitivity (pptv) and short sample collection times (≤15 s) to maximize spatial resolution and sampling frequency for targeted plume analysis. The use of stainless steel canisters to collect whole air samples (WAS) for post-flight analysis has been pioneered by the groups of D. Blake and E. Atlas [Blake et al., 1992; Atlas et al., 1993]. For the 2013 Southeast Nexus Study (SENEX), the NOAA ESRL CSD laboratory undertook WAS measurements for the first time. This required the construction of three new, highly-automated, and field-portable instruments designed to sample, analyze, and clean the canisters for re-use. Analysis was performed with a new custom-built gas chromatograph-mass spectrometer system. The instrument pre-concentrates analyte cryostatically into two parallel traps by means of a Stirling engine, a novel technique which obviates the need for liquid nitrogen to reach trapping temperatures of -175C. Here we present an evaluation of the retrieval of target VOC species from WAS canisters. We discuss the effects of humidity and sample age on the analyte, particularly upon C8+ alkane and aromatic species and biogenic species. Finally, we present results from several research flights during SENEX that targeted emissions from oil/natural gas production.

  11. Adaptive Sampling for Urban Air Quality through Participatory Sensing

    PubMed Central

    Zeng, Yuanyuan; Xiang, Kai

    2017-01-01

    Air pollution is one of the major problems of the modern world. The popularization and powerful functions of smartphone applications enable people to participate in urban sensing to better know about the air problems surrounding them. Data sampling is one of the most important problems that affect the sensing performance. In this paper, we propose an Adaptive Sampling Scheme for Urban Air Quality (AS-air) through participatory sensing. Firstly, we propose to find the pattern rules of air quality according to the historical data contributed by participants based on Apriori algorithm. Based on it, we predict the on-line air quality and use it to accelerate the learning process to choose and adapt the sampling parameter based on Q-learning. The evaluation results show that AS-air provides an energy-efficient sampling strategy, which is adaptive toward the varied outside air environment with good sampling efficiency. PMID:29099766

  12. Analysis of EPA and DOE WIPP Air Sampling Data

    EPA Pesticide Factsheets

    During the April 2014 EPA visit to WIPP, EPA co-located four ambient air samplers with existing Department of Energy (DOE) ambient air samplers to independently corroborate DOE's reported air sampling results.

  13. Innovations in air sampling to detect plant pathogens

    PubMed Central

    West, JS; Kimber, RBE

    2015-01-01

    Many innovations in the development and use of air sampling devices have occurred in plant pathology since the first description of the Hirst spore trap. These include improvements in capture efficiency at relatively high air-volume collection rates, methods to enhance the ease of sample processing with downstream diagnostic methods and even full automation of sampling, diagnosis and wireless reporting of results. Other innovations have been to mount air samplers on mobile platforms such as UAVs and ground vehicles to allow sampling at different altitudes and locations in a short space of time to identify potential sources and population structure. Geographical Information Systems and the application to a network of samplers can allow a greater prediction of airborne inoculum and dispersal dynamics. This field of technology is now developing quickly as novel diagnostic methods allow increasingly rapid and accurate quantifications of airborne species and genetic traits. Sampling and interpretation of results, particularly action-thresholds, is improved by understanding components of air dispersal and dilution processes and can add greater precision in the application of crop protection products as part of integrated pest and disease management decisions. The applications of air samplers are likely to increase, with much greater adoption by growers or industry support workers to aid in crop protection decisions. The same devices are likely to improve information available for detection of allergens causing hay fever and asthma or provide valuable metadata for regional plant disease dynamics. PMID:25745191

  14. NHEXAS PHASE I ARIZONA STUDY--METALS IN AIR ANALYTICAL RESULTS

    EPA Science Inventory

    The Metals in Air data set contains analytical results for measurements of up to 11 metals in 369 air samples over 175 households. Samples were taken by pumping standardized air volumes through filters at indoor and outdoor sites around each household being sampled. The primary...

  15. 40 CFR 61.34 - Air sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 8 2011-07-01 2011-07-01 false Air sampling. 61.34 Section 61.34... sampling. (a) Stationary sources subject to § 61.32(b) shall locate air sampling sites in accordance with a... concentrations calculated within 30 days after filters are collected. Records of concentrations at all sampling...

  16. Air Sampling Filter

    NASA Technical Reports Server (NTRS)

    1980-01-01

    General Metal Works' Accu-Vol is a high-volume air sampling system used by many government agencies to monitor air quality for pollution control purposes. Procedure prevents possible test-invalidating contamination from materials other than particulate pollutants, caused by manual handling or penetration of windblown matter during transit, a cassette was developed in which the filter is sealed within a metal frame and protected in transit by a snap-on aluminum cover, thus handled only under clean conditions in the laboratory.

  17. Air sampling methods to evaluate microbial contamination in operating theatres: results of a comparative study in an orthopaedics department.

    PubMed

    Napoli, C; Tafuri, S; Montenegro, L; Cassano, M; Notarnicola, A; Lattarulo, S; Montagna, M T; Moretti, B

    2012-02-01

    To evaluate the level of microbial contamination of air in operating theatres using active [i.e. surface air system (SAS)] and passive [i.e. index of microbial air contamination (IMA) and nitrocellulose membranes positioned near the wound] sampling systems. Sampling was performed between January 2010 and January 2011 in the operating theatre of the orthopaedics department in a university hospital in Southern Italy. During surgery, the mean bacterial loads recorded were 2232.9 colony-forming units (cfu)/m(2)/h with the IMA method, 123.2 cfu/m(3) with the SAS method and 2768.2 cfu/m(2)/h with the nitrocellulose membranes. Correlation was found between the results of the three methods. Staphylococcus aureus was detected in 12 of 60 operations (20%) with the membranes, five (8.3%) operations with the SAS method, and three operations (5%) with the IMA method. Use of nitrocellulose membranes placed near a wound is a valid method for measuring the microbial contamination of air. This method was more sensitive than the IMA method and was not subject to any calibration bias, unlike active air monitoring systems. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  18. Presence of organophosphorus pesticide oxygen analogs in air samples

    NASA Astrophysics Data System (ADS)

    Armstrong, Jenna L.; Fenske, Richard A.; Yost, Michael G.; Galvin, Kit; Tchong-French, Maria; Yu, Jianbo

    2013-02-01

    A number of recent toxicity studies have highlighted the increased potency of oxygen analogs (oxons) of several organophosphorus (OP) pesticides. These findings were a major concern after environmental oxons were identified in environmental samples from air and surfaces following agricultural spray applications in California and Washington State. This paper reports on the validity of oxygen analog measurements in air samples for the OP pesticide, chlorpyrifos. Controlled environmental and laboratory experiments were used to examine artificial formation of chlorpyrifos-oxon using OSHA Versatile Sampling (OVS) tubes as recommended by NIOSH method 5600. Additionally, we compared expected chlorpyrifos-oxon attributable to artificial transformation to observed chlorpyrifos-oxon in field samples from a 2008 Washington State Department of Health air monitoring study using non-parametric statistical methods. The amount of artificially transformed oxon was then modeled to determine the amount of oxon present in the environment. Toxicity equivalency factors (TEFs) for chlorpyrifos-oxon were used to calculate chlorpyrifos-equivalent air concentrations. The results demonstrate that the NIOSH-recommended sampling matrix (OVS tubes with XAD-2 resin) was found to artificially transform up to 30% of chlorpyrifos to chlorpyrifos-oxon, with higher percentages at lower concentrations (<30 ng m-3) typical of ambient or residential levels. Overall, the 2008 study data had significantly greater oxon than expected by artificial transformation, but the exact amount of environmental oxon in air remains difficult to quantify with the current sampling method. Failure to conduct laboratory analysis for chlorpyrifos-oxon may result in underestimation of total pesticide concentration when using XAD-2 resin matrices for occupational or residential sampling. Alternative methods that can accurately measure both OP pesticides and their oxygen analogs should be used for air sampling, and a toxicity

  19. A survey of recent results in passive sampling of water and air by semipermeable membrane devices

    USGS Publications Warehouse

    Prest, Harry F.; Huckins, James N.; Petty, Jimmie D.; Herve, Sirpa; Paasivirta, Jaakko; Heinonen, Pertti

    1995-01-01

    A survey is presented of some recent results for passive sampling of water and air for trace organic contaminants using lipid-filled semipermeable membrane devices (SPMDs). Results of water sampling for trace organochlorine compounds using simultaneously exposed SPMDs and the most universally applied biomonitor (bivalves) are discussed. In general, the total amounts of accumulated analytes available for analysis in bivalves and SPMDs were comparable. However, SPMD controls typically had negligible levels of contamination, which was not always the case for transplanted bivalves, even after prolonged depuration prior to exposure. In surveys of the spatial trends of organochlorines at a series of sites, data from bivalves and SPMDs provided the same picture of contaminant distribution and severity. An exception was ionizable contaminants such as the chlorinated phenolic compounds and their transformation products found in pulp mill effluents. In these cases the two monitoring approaches compliment each other, i.e. what is not found in bivalves appears in SPMDs and vice versa. SPMDs have also been applied in environments where biomonitoring is not feasible. SPMDs have shown their utility in studies of trace levels of polyaromatic hydrocarbons by locating and characterizing point sources. An example is given of their application to the calculation of contaminant half-lives from aqueous SPMD residues, a direct measurement of the persistence of contaminants in an environmental compartment. Similarly, results of air sampling with SPMDs in a relatively pristine coastal location are cited which reveal a tremendous enhancement in p,p′-DDE relative to open ocean values.

  20. Diagnosing AIRS Sampling with CloudSat Cloud Classes

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric; Yue, Qing; Guillaume, Alexandre; Kahn, Brian

    2011-01-01

    AIRS yield and sampling vary with cloud state. Careful utilization of collocated multiple satellite sensors is necessary. Profile differences between AIRS and ECMWF model analyses indicate that AIRS has high sampling and excellent accuracy for certain meteorological conditions. Cloud-dependent sampling biases may have large impact on AIRS L2 and L3 data in climate research. MBL clouds / lower tropospheric stability relationship is one example. AIRS and CloudSat reveal a reasonable climatology in the MBL cloud regime despite limited sampling in stratocumulus. Thermodynamic parameters such as EIS derived from AIRS data map these cloud conditions successfully. We are working on characterizing AIRS scenes with mixed cloud types.

  1. 40 CFR 61.34 - Air sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Air sampling. 61.34 Section 61.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.34 Air...

  2. 40 CFR 61.34 - Air sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Air sampling. 61.34 Section 61.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.34 Air...

  3. NHEXAS PHASE I MARYLAND STUDY--PESTICIDES IN AIR ANALYTICAL RESULTS

    EPA Science Inventory

    The Pesticides in Air data set contains analytical results for measurements of up to 9 pesticides in 127 air samples over 51 households. Samples were taken by pumping standardized air volumes through URG impactors with a 10 um cutpoint and polyurethane foam (PUF) filters at indo...

  4. NHEXAS PHASE I MARYLAND STUDY--PAHS IN AIR ANALYTICAL RESULTS

    EPA Science Inventory

    The PAHs in Air data set contains analytical results for measurements of up to 11 PAHs in 127 air samples over 51 households. Twenty-four-hour samples were taken over a one-week period using a continuous pump and solenoid apparatus pumping a standardized air volume through an UR...

  5. NHEXAS PHASE I MARYLAND STUDY--METALS IN AIR ANALYTICAL RESULTS

    EPA Science Inventory

    The Metals in Air data set contains analytical results for measurements of up to 4 metals in 458 air samples over 79 households. Twenty-four-hour samples were taken over a one-week period using a continuous pump and solenoid apparatus by pumping a standardized air volume through...

  6. Carter Carburetor Weekly Air Monitoring & Sampling Report - March 7, 2013 - March 13, 2016

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  7. Carter Carburetor Weekly Air Monitoring & Sampling Report - November 30, 2015 – December 6, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  8. Carter Carburetor Weekly Air Monitoring & Sampling Report - October 26, 2015 – November 1, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  9. Carter Carburetor Weekly Air Monitoring & Sampling Report - February 15, 2016 – February 21, 2016

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  10. Carter Carburetor Weekly Air Monitoring & Sampling Report - October 12, 2015 – October 18, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  11. Carter Carburetor Weekly Air Monitoring & Sampling Report - November 23, 2015 – November 29, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  12. Carter Carburetor Weekly Air Monitoring & Sampling Report - October 5, 2015 – October 11, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  13. Carter Carburetor Weekly Air Monitoring & Sampling Report - February 1, 2016 – February 7, 2016

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  14. Carter Carburetor Weekly Air Monitoring & Sampling Report - September 28, 2015 – October 4, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  15. Carter Carburetor Weekly Air Monitoring & Sampling Report - November 16, 2015 – November 22, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  16. Carter Carburetor Weekly Air Monitoring & Sampling Report - November 9, 2015 – November 15, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  17. Carter Carburetor Weekly Air Monitoring & Sampling Report - October 19, 2015 – October 25, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  18. Carter Carburetor Weekly Air Monitoring & Sampling Report - November 2, 2015 – November 8, 2015

    EPA Pesticide Factsheets

    Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati

  19. A new device for dynamic sampling of radon in air

    NASA Astrophysics Data System (ADS)

    Lozano, J. C.; Escobar, V. Gómez; Tomé, F. Vera

    2000-08-01

    A new system is proposed for the active sampling of radon in air, based on the well-known property of activated charcoal to retain radon. Two identical carbon-activated cartridges arranged in series remove the radon from the air being sampled. The air passes first through a desiccant cell and then the carbon cartridges for short sampling times using a low-flow pump. The alpha activity for each cartridge is determined by a liquid scintillation counting system. The cartridge is placed in a holder into a vial that also contains the appropriate amount of scintillation cocktail, in a way that avoids direct contact between cocktail and charcoal. Once dynamic equilibrium between the phases has been reached, the vials can be counted. Optimum sampling conditions concerning flow rates and sampling times are determined. Using those conditions, the method was applied to environmental samples, straightforwardly providing good results for very different levels of activity.

  20. U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--METALS IN AIR ANALYTICAL RESULTS

    EPA Science Inventory

    The Metals in Air data set contains analytical results for measurements of up to 11 metals in 344 air samples over 86 households. Samples were taken by pumping standardized air volumes through filters at indoor and outdoor sites around each household being sampled. The primary ...

  1. Passive air sampling theory for semivolatile organic compounds.

    PubMed

    Bartkow, Michael E; Booij, Kees; Kennedy, Karen E; Müller, Jochen F; Hawker, Darryl W

    2005-07-01

    The mathematical modelling underlying passive air sampling theory can be based on mass transfer coefficients or rate constants. Generally, these models have not been inter-related. Starting with basic models, the exchange of chemicals between the gaseous phase and the sampler is developed using mass transfer coefficients and rate constants. Importantly, the inter-relationships between the approaches are demonstrated by relating uptake rate constants and loss rate constants to mass transfer coefficients when either sampler-side or air-side resistance is dominating chemical exchange. The influence of sampler area and sampler volume on chemical exchange is discussed in general terms and as they relate to frequently used parameters such as sampling rates and time to equilibrium. Where air-side or sampler-side resistance dominates, an increase in the surface area of the sampler will increase sampling rates. Sampling rates are not related to the sampler/air partition coefficient (K(SV)) when air-side resistance dominates and increase with K(SV) when sampler-side resistance dominates.

  2. Sampling for Air Chemical Emissions from the Life Sciences Laboratory II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ballinger, Marcel Y.; Lindberg, Michael J.

    Sampling for air chemical emissions from the Life Science Laboratory II (LSL-II) ventilation stack was performed in an effort to determine potential exposure of maintenance staff to laboratory exhaust on the building roof. The concern about worker exposure was raised in December 2015 and several activities were performed to assist in estimating exposure concentrations. Data quality objectives were developed to determine the need for and scope and parameters of a sampling campaign to measure chemical emissions from research and development activities to the outside air. The activities provided data on temporal variation of air chemical concentrations and a basis formore » evaluating calculated emissions. Sampling for air chemical emissions was performed in the LSL-II ventilation stack over the 6-week period from July 26 to September 1, 2016. A total of 12 sampling events were carried out using 16 sample media. Resulting analysis provided concentration data on 49 analytes. All results were below occupational exposure limits and most results were below detection limits. When compared to calculated emissions, only 5 of the 49 chemicals had measured concentrations greater than predicted. This sampling effort will inform other study components to develop a more complete picture of a worker’s potential exposure from LSL-II rooftop activities. Mixing studies were conducted to inform spatial variation in concentrations at other rooftop locations and can be used in conjunction with these results to provide temporal variations in concentrations for estimating the potential exposure to workers working in and around the LSL-II stack.« less

  3. COMPARISON OF 24H AVERAGE VOC MONITORING RESULTS FOR RESIDENTIAL INDOOR AND OUTDOOR AIR USING CARBOPACK X-FILLED DIFFUSIVE SAMPLERS AND ACTIVE SAMPLING - A PILOT STUDY

    EPA Science Inventory

    Analytical results obtained by thermal desorption GC/MS for 24h diffusive sampling of 11 volatile organic compounds (VOCs) are compared with results of time-averaged active sampling at a known constant flow rate. Air samples were collected with co-located duplicate diffusive samp...

  4. Comparison of stationary and personal air sampling with an ...

    EPA Pesticide Factsheets

    Manganese (Mn) is ubiquitous in the environment and essential for normal growth and development, yet excessive exposure can lead to impairments in neurological function. This study modeled ambient Mn concentrations as an alternative to stationary and personal air sampling to assess exposure for children enrolled in the Communities Actively Researching Exposure Study in Marietta, OH. Ambient air Mn concentration values were modeled using US Environmental Protection Agency’s Air Dispersion Model AERMOD based on emissions from the ferromanganese refinery located in Marietta. Modeled Mn concentrations were compared with Mn concentrations from a nearby stationary air monitor. The Index of Agreement for modeled versus monitored data was 0.34 (48 h levels) and 0.79 (monthly levels). Fractional bias was 0.026 for 48 h levels and −0.019 for monthly levels. The ratio of modeled ambient air Mn to measured ambient air Mn at the annual time scale was 0.94. Modeled values were also time matched to personal air samples for 19 children. The modeled values explained a greater degree of variability in personal exposures compared with time-weighted distance from the emission source. Based on these results modeled Mn concentrations provided a suitable approach for assessing airborne Mn exposure in this cohort. The purpose of the study was to investigate the use of air-dispersion modeling as an approach to exposure assessment for ambient manganese.

  5. Double-layer Tedlar bags: a means to limit humidity evolution of air samples and to dry humid air samples.

    PubMed

    Cariou, Stephane; Guillot, Jean-Michel

    2006-01-01

    Tedlar bags, which are widely used to collect air samples, especially VOCs and odorous atmospheres, can allow humidity to diffuse when relative humidity levels differ between the inside and outside. Starting with dry air inside the bag and humid air outside, we monitored equilibrium times under several conditions showing the evolution and influence of collected volumes and exposed surfaces. A double-film Tedlar bag was made, to limit the impact of external humidity on a sample at low humidity level. With the addition of a drying agent between both films, the evolution of humidity of a sample can be stopped for several hours. When a VOC mixture was monitored in a humid atmosphere, humidity was decreased but no significant evolution of VOC concentrations was observed.

  6. NHEXAS PHASE I ARIZONA STUDY--QA ANALYTICAL RESULTS FOR METALS IN BLANK SAMPLES

    EPA Science Inventory

    The Metals in Blank Samples data set contains the analytical results of measurements of up to 27 metals in 82 blank samples from 26 households. Measurements were made in blank samples of dust, indoor and outdoor air, personal air, food, beverages, blood, urine, and dermal wipe r...

  7. Detection of the urban release of a bacillus anthracis simulant by air sampling.

    PubMed

    Garza, Alexander G; Van Cuyk, Sheila M; Brown, Michael J; Omberg, Kristin M

    2014-01-01

    In 2005 and 2009, the Pentagon Force Protection Agency (PFPA) staged deliberate releases of a commercially available organic pesticide containing Bacillus amyloliquefaciens to evaluate PFPA's biothreat response protocols. In concert with, but independent of, these releases, the Department of Homeland Security sponsored experiments to evaluate the efficacy of commonly employed air and surface sampling techniques for detection of an aerosolized biological agent. High-volume air samplers were placed in the expected downwind plume, and samples were collected before, during, and after the releases. Environmental surface and personal air samples were collected in the vicinity of the high-volume air samplers hours after the plume had dispersed. The results indicate it is feasible to detect the release of a biological agent in an urban area both during and after the release of a biological agent using high-volume air and environmental sampling techniques.

  8. Air Quality and Road Emission Results for Fort Stewart, Georgia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kirkham, Randy R.; Driver, Crystal J.; Chamness, Mickie A.

    2004-02-02

    The Directorate of Public Works Environmental & Natural Resources Division (Fort Stewart /Hunter Army Airfield) contracted with the Pacific Northwest National Laboratory (PNNL) to monitor particulate matter (PM) concentrations on Fort Stewart, Georgia. The purpose of this investigation was to establish a PM sampling network using monitoring equipment typically used in U.S. Environmental Protection Agency (EPA) ''saturation sampling'', to determine air quality on the installation. In this initial study, the emphasis was on training-generated PM, not receptor PM loading. The majority of PM samples were 24-hr filter-based samples with sampling frequency ranging from every other day, to once every sixmore » days synchronized with the EPA 6th day national sampling schedule. Eight measurement sites were established and used to determine spatial variability in PM concentrations and evaluate whether fluctuations in PM appear to result from training activities and forest management practices on the installation. Data collected to date indicate the average installation PM2.5 concentration is lower than that of nearby urban Savannah, Georgia. At three sites near the installation perimeter, analyses to segregate PM concentrations by direction of air flow across the installation boundary indicate that air (below 80 ft) leaving the installation contains less PM2.5 than that entering the installation. This is reinforced by the observation that air near the ground is cleaner on average than the air at the top of the canopy.« less

  9. Monitoring airborne fungal spores in an experimental indoor environment to evaluate sampling methods and the effects of human activity on air sampling.

    PubMed Central

    Buttner, M P; Stetzenbach, L D

    1993-01-01

    Aerobiological monitoring was conducted in an experimental room to aid in the development of standardized sampling protocols for airborne microorganisms in the indoor environment. The objectives of this research were to evaluate the relative efficiencies of selected sampling methods for the retrieval of airborne fungal spores and to determine the effect of human activity on air sampling. Dry aerosols containing known concentrations of Penicillium chrysogenum spores were generated, and air samples were taken by using Andersen six-stage, Surface Air System, Burkard, and depositional samplers. The Andersen and Burkard samplers retrieved the highest numbers of spores compared with the measurement standard, an aerodynamic particle sizer located inside the room. Data from paired samplers demonstrated that the Andersen sampler had the highest levels of sensitivity and repeatability. With a carpet as the source of P. chrysogenum spores, the effects of human activity (walking or vacuuming near the sampling site) on air sampling were also examined. Air samples were taken under undisturbed conditions and after human activity in the room. Human activity resulted in retrieval of significantly higher concentrations of airborne spores. Surface sampling of the carpet revealed moderate to heavy contamination despite relatively low airborne counts. Therefore, in certain situations, air sampling without concomitant surface sampling may not adequately reflect the level of microbial contamination in indoor environments. PMID:8439150

  10. Novel sample preparation technique with needle-type micro-extraction device for volatile organic compounds in indoor air samples.

    PubMed

    Ueta, Ikuo; Mizuguchi, Ayako; Fujimura, Koji; Kawakubo, Susumu; Saito, Yoshihiro

    2012-10-09

    A novel needle-type sample preparation device was developed for the effective preconcentration of volatile organic compounds (VOCs) in indoor air before gas chromatography-mass spectrometry (GC-MS) analysis. To develop a device for extracting a wide range of VOCs typically found in indoor air, several types of particulate sorbents were tested as the extraction medium in the needle-type extraction device. To determine the content of these VOCs, air samples were collected for 30min with the packed sorbent(s) in the extraction needle, and the extracted VOCs were thermally desorbed in a GC injection port by the direct insertion of the needle. A double-bed sorbent consisting of a needle packed with divinylbenzene and activated carbon particles exhibited excellent extraction and desorption performance and adequate extraction capacity for all the investigated VOCs. The results also clearly demonstrated that the proposed sample preparation method is a more rapid, simpler extraction/desorption technique than traditional sample preparation methods. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. [Microbial air monitoring in operating theatre: active and passive samplings].

    PubMed

    Pasquarella, C; Masia, M D; Nnanga, Nga; Sansebastiano, G E; Savino, A; Signorelli, C; Veronesi, L

    2004-01-01

    Microbial air contamination was evaluated in 11 operating theatres using active and passive samplings. SAS (Surface Air System) air sampling was used to evaluate cfu/m3 and settle plates were used to measure the index of microbial air contamination (IMA). Samplings were performed at the same time on three different days, at three different times (before, during and after the surgical activity). Two points were monitored (patient area and perimeter of the operating theatre). Moreover, the cfu/m3 were evaluated at the air inlet of the conditioner system. 74.7% of samplings performed at the air inlet and 66.7% of the samplings performed at the patient area before the beginning of the surgical activity (at rest) exceeded the 35 cfu/m3 used as threshold value. 100% of IMA values exceeded the threshold value of 5. Using both active and passive sampling, the microbial contamination was shown to increase significantly during activity. The cfu values were higher at the patient area than at the perimeter of the operating theatre. Mean values of the cfu/m3 during activity at the patient area ranged from a minimum of 61+/-41 cfu/m3 to a maximum of 242+/-136 cfu/m3; IMA values ranged from a minimum of 19+/-10 to a maximum of 129+/-60. 15.2% of samplings performed at the patient area using SAS and 75.8% of samplings performed using settle plates exceeded the threshold values of 180 cfu/m3 and 25 respectively, with a significant difference of the percentages. The highest values were found in the operating theatre with inadequate structural and managerial conditions. These findings confirm that the microbiological quality of air may be considered a mirror of the hygienic conditions of the operating theatre. Settle plates proved to be more sensitive in detecting the increase of microbial air contamination related to conditions that could compromise the quality of the air in operating theatres.

  12. A simple novel device for air sampling by electrokinetic capture.

    PubMed

    Gordon, Julian; Gandhi, Prasanthi; Shekhawat, Gajendra; Frazier, Angel; Hampton-Marcell, Jarrad; Gilbert, Jack A

    2015-12-27

    A variety of different sampling devices are currently available to acquire air samples for the study of the microbiome of the air. All have a degree of technical complexity that limits deployment. Here, we evaluate the use of a novel device, which has no technical complexity and is easily deployable. An air-cleaning device powered by electrokinetic propulsion has been adapted to provide a universal method for collecting samples of the aerobiome. Plasma-induced charge in aerosol particles causes propulsion to and capture on a counter-electrode. The flow of ions creates net bulk airflow, with no moving parts. A device and electrode assembly have been re-designed from air-cleaning technology to provide an average air flow of 120 lpm. This compares favorably with current air sampling devices based on physical air pumping. Capture efficiency was determined by comparison with a 0.4 μm polycarbonate reference filter, using fluorescent latex particles in a controlled environment chamber. Performance was compared with the same reference filter method in field studies in three different environments. For 23 common fungal species by quantitative polymerase chain reaction (qPCR), there was 100 % sensitivity and apparent specificity of 87 %, with the reference filter taken as "gold standard." Further, bacterial analysis of 16S RNA by amplicon sequencing showed equivalent community structure captured by the electrokinetic device and the reference filter. Unlike other current air sampling methods, capture of particles is determined by charge and so is not controlled by particle mass. We analyzed particle sizes captured from air, without regard to specific analyte by atomic force microscopy: particles at least as low as 100 nM could be captured from ambient air. This work introduces a very simple plug-and-play device that can sample air at a high-volume flow rate with no moving parts and collect particles down to the sub-micron range. The performance of the device is

  13. A STRINGENT COMPARISON OF SAMPLING AND ANALYSIS METHODS FOR VOCS IN AMBIENT AIR

    EPA Science Inventory

    A carefully designed study was conducted during the summer of 1998 to simultaneously collect samples of ambient air by canisters and compare the analysis results to direct sorbent preconcentration results taken at the time of sample collection. A total of 32 1-h sample sets we...

  14. Uncertainties in monitoring of SVOCs in air caused by within-sampler degradation during active and passive air sampling

    NASA Astrophysics Data System (ADS)

    Melymuk, Lisa; Bohlin-Nizzetto, Pernilla; Prokeš, Roman; Kukučka, Petr; Přibylová, Petra; Vojta, Šimon; Kohoutek, Jiří; Lammel, Gerhard; Klánová, Jana

    2017-10-01

    Degradation of semivolatile organic compounds (SVOCs) occurs naturally in ambient air due to reactions with reactive trace gases (e.g., ozone, NOx). During air sampling there is also the possibility for degradation of SVOCs within the air sampler, leading to underestimates of ambient air concentrations. We investigated the possibility of this sampling artifact in commonly used active and passive air samplers for seven classes of SVOCs, including persistent organic pollutants (POPs) typically covered by air monitoring programs, as well as SVOCs of emerging concern. Two active air samplers were used, one equipped with an ozone denuder and one without, to compare relative differences in mass of collected compounds. Two sets of passive samplers were also deployed to determine the influence of degradation during longer deployment times in passive sampling. In active air samplers, comparison of the two sampling configurations suggested degradation of particle-bound polycyclic aromatic hydrocarbons (PAHs), with concentrations up to 2× higher in the denuder-equipped sampler, while halogenated POPs did not have clear evidence of degradation. In contrast, more polar, reactive compounds (e.g., organophosphate esters and current use pesticides) had evidence of losses in the sampler with denuder. This may be caused by the denuder itself, suggesting sampling bias for these compounds can be created when typical air sampling apparatuses are adapted to limit degradation. Passive air samplers recorded up to 4× higher concentrations when deployed for shorter consecutive sampling periods, suggesting that within-sampler degradation may also be relevant in passive air monitoring programs.

  15. 30 CFR 90.205 - Approved sampling devices; operation; air flowrate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved sampling devices; operation; air... LABOR COAL MINE SAFETY AND HEALTH MANDATORY HEALTH STANDARDS-COAL MINERS WHO HAVE EVIDENCE OF THE DEVELOPMENT OF PNEUMOCONIOSIS Sampling Procedures § 90.205 Approved sampling devices; operation; air flowrate...

  16. Convair F-106B Delta Dart with Air Sampling Equipment

    NASA Image and Video Library

    1974-04-21

    The National Aeronautics and Space Administration (NASA) Lewis Research Center’s Convair F-106B Delta Dart equipped with air sampling equipment in the mid-1970s. NASA Lewis created and managed the Global Air Sampling Program (GASP) in 1972 in partnership with several airline companies. NASA researchers used the airliners’ Boeing 747 aircraft to gather air samples to determine the amount of pollution present in the stratosphere. Private companies developed the air sampling equipment for the GASP program, and Lewis created a particle collector. The collector was flight tested on NASA Lewis’ F-106B in the summer of 1973. The sampling equipment was automatically operated once the proper altitude was achieved. The sampling instruments collected dust particles in the air so their chemical composition could be analyzed. The equipment analyzed one second’s worth of data at a time. The researchers also monitored carbon monoxide, monozide, ozone, and water vapor. The 747 flights began in December 1974 and soon included four airlines flying routes all over the globe. The F-106B augmented the airline data with sampling of its own, seen here. It gathered samples throughout this period from locations such as New Mexico, Texas, Michigan, and Ohio. In July 1977 the F-106B flew eight GASP flights in nine days over Alaska to supplement the earlier data gathered by the airlines.

  17. Systematic Evaluation of Aggressive Air Sampling for Bacillus ...

    EPA Pesticide Factsheets

    Report The primary objectives of this project were to evaluate the Aggressive Air Sampling (AAS) method compared to currently used surface sampling methods and to determine if AAS is a viable option for sampling Bacillus anthracis spores.

  18. A simple novel device for air sampling by electrokinetic capture

    DOE PAGES

    Gordon, Julian; Gandhi, Prasanthi; Shekhawat, Gajendra; ...

    2015-12-27

    A variety of different sampling devices are currently available to acquire air samples for the study of the microbiome of the air. All have a degree of technical complexity that limits deployment. Here, we evaluate the use of a novel device, which has no technical complexity and is easily deployable. An air-cleaning device powered by electrokinetic propulsion has been adapted to provide a universal method for collecting samples of the aerobiome. Plasma-induced charge in aerosol particles causes propulsion to and capture on a counter-electrode. The flow of ions creates net bulk airflow, with no moving parts. A device and electrodemore » assembly have been re-designed from air-cleaning technology to provide an average air flow of 120 lpm. This compares favorably with current air sampling devices based on physical air pumping. Capture efficiency was determined by comparison with a 0.4 μm polycarbonate reference filter, using fluorescent latex particles in a controlled environment chamber. Performance was compared with the same reference filter method in field studies in three different environments. For 23 common fungal species by quantitative polymerase chain reaction (qPCR), there was 100 % sensitivity and apparent specificity of 87%, with the reference filter taken as “gold standard.” Further, bacterial analysis of 16S RNA by amplicon sequencing showed equivalent community structure captured by the electrokinetic device and the reference filter. Unlike other current air sampling methods, capture of particles is determined by charge and so is not controlled by particle mass. We analyzed particle sizes captured from air, without regard to specific analyte by atomic force microscopy: particles at least as low as 100 nM could be captured from ambient air. This work introduces a very simple plug-and-play device that can sample air at a high-volume flow rate with no moving parts and collect particles down to the sub-micron range. In conclusion, the performance of

  19. A simple novel device for air sampling by electrokinetic capture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gordon, Julian; Gandhi, Prasanthi; Shekhawat, Gajendra

    A variety of different sampling devices are currently available to acquire air samples for the study of the microbiome of the air. All have a degree of technical complexity that limits deployment. Here, we evaluate the use of a novel device, which has no technical complexity and is easily deployable. An air-cleaning device powered by electrokinetic propulsion has been adapted to provide a universal method for collecting samples of the aerobiome. Plasma-induced charge in aerosol particles causes propulsion to and capture on a counter-electrode. The flow of ions creates net bulk airflow, with no moving parts. A device and electrodemore » assembly have been re-designed from air-cleaning technology to provide an average air flow of 120 lpm. This compares favorably with current air sampling devices based on physical air pumping. Capture efficiency was determined by comparison with a 0.4 μm polycarbonate reference filter, using fluorescent latex particles in a controlled environment chamber. Performance was compared with the same reference filter method in field studies in three different environments. For 23 common fungal species by quantitative polymerase chain reaction (qPCR), there was 100 % sensitivity and apparent specificity of 87%, with the reference filter taken as “gold standard.” Further, bacterial analysis of 16S RNA by amplicon sequencing showed equivalent community structure captured by the electrokinetic device and the reference filter. Unlike other current air sampling methods, capture of particles is determined by charge and so is not controlled by particle mass. We analyzed particle sizes captured from air, without regard to specific analyte by atomic force microscopy: particles at least as low as 100 nM could be captured from ambient air. This work introduces a very simple plug-and-play device that can sample air at a high-volume flow rate with no moving parts and collect particles down to the sub-micron range. In conclusion, the performance of

  20. Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study.

    PubMed

    Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D'Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira

    2017-06-22

    Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis ® μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis ® μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis ® μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis ® μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.

  1. Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study

    PubMed Central

    Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D’Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira

    2017-01-01

    Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis®μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis®μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis®μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis®μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations. PMID:28640202

  2. [Air-conditioner disease. Results of an industrial medicine survey (author's transl)].

    PubMed

    Molina, C; Aiache, J M; Bedu, M; Menaut, P; Wahl, D; Brestowski, J; Grall, Y

    1982-07-03

    The results of a survey conducted in a company employing 1850 persons working in air-conditioned premises are reported. One hundred and five persons were examined, including 790 who mostly complained of respiratory disorders and 20 controls. Regular check-ups during the last two years have failed to reveal any serious disease. The most frequent complaints were rhinitis and tracheitis, especially among female employees. No alveolitis was observed. The finding of Bacillus subtilis in samples of ambient air and air-conditioner filters in conjunction with the presence of precipitating antibodies against crude extracts from these samples, suggested that the respiratory disorders might have been due to this microorganism. A multifactorial analysis demonstrated a statistically significant correlation between clinical symptoms and immunological disorders. The air-conditioner disease, therefore, may present as a benign condition.

  3. Comparison of the Results of Studies of Air Pollution Fungi Using the SAS Super 100, MAS 100, and Air IDEAL.

    PubMed

    Łukaszuk, Cecylia; Krajewska-Kułak, Elżbieta; Guzowski, Andrzej; Kułak, Wojciech; Kraszyńska, Bogumiła

    2017-07-20

    Although several air sampling devices for identifying and enumerating airborne microorganisms are commercially available, each poses some limitations. The aim of this study was to evaluate air pollution fungi using three such samplers: SAS Super 100, Microbiological Air Sampler (MAS) 100, and Air IDEAL. Mycological air was taken from the cellars of a 17th-century church in Siemiatycze, Poland, and the nearby outdoor environment. With samplers placed 1.5 m above the floor, microbial flora in air samples collected inside and outside the cellar were detected. The number of colony-forming units (CFU) of fungi obtained with the three samplers from the cellars and outdoor environment differed; the most CFU were obtained with the Air IDEAL and the least with the SAS Super 100. Significant differences emerged in CFUs collected from air samples with the MAS 100 and SAS Super 100, on the one hand, and the SAS Super 100 and Air IDEAL, on the other. Otherwise, results among the samplers were different. More Cladosporium species were collected with the MAS 100 sampler, whereas more Fusarium and Aspergillus species were collected with the Air IDEAL sampler. Significant differences among CFU/m³ values among the tested sites depended on the sampler used.

  4. Comparison of indoor air sampling and dust collection methods for fungal exposure assessment using quantitative PCR.

    PubMed

    Cox, Jennie; Indugula, Reshmi; Vesper, Stephen; Zhu, Zheng; Jandarov, Roman; Reponen, Tiina

    2017-10-18

    Evaluating fungal contamination indoors is complicated because of the many different sampling methods utilized. In this study, fungal contamination was evaluated using five sampling methods and four matrices for results. The five sampling methods were a 48 hour indoor air sample collected with a Button™ inhalable aerosol sampler and four types of dust samples: a vacuumed floor dust sample, newly settled dust collected for four weeks onto two types of electrostatic dust cloths (EDCs) in trays, and a wipe sample of dust from above floor surfaces. The samples were obtained in the bedrooms of asthmatic children (n = 14). Quantitative polymerase chain reaction (qPCR) was used to analyze the dust and air samples for the 36 fungal species that make up the Environmental Relative Moldiness Index (ERMI). The results from the samples were compared by four matrices: total concentration of fungal cells, concentration of fungal species associated with indoor environments, concentration of fungal species associated with outdoor environments, and ERMI values (or ERMI-like values for air samples). The ERMI values for the dust samples and the ERMI-like values for the 48 hour air samples were not significantly different. The total cell concentrations of the 36 species obtained with the four dust collection methods correlated significantly (r = 0.64-0.79, p < 0.05), with the exception of the vacuumed floor dust and newly settled dust. In addition, fungal cell concentrations of indoor associated species correlated well between all four dust sampling methods (r = 0.68-0.86, p < 0.01). No correlation was found between the fungal concentrations in the air and dust samples primarily because of differences in concentrations of Cladosporium cladosporioides Type 1 and Epicoccum nigrum. A representative type of dust sample and a 48 hour air sample might both provide useful information about fungal exposures.

  5. Can car air filters be useful as a sampling medium for air pollution monitoring purposes?

    PubMed

    Katsoyiannis, Athanasios; Birgul, Askin; Ratola, Nuno; Cincinelli, Alessandra; Sweetman, Andy J; Jones, Kevin C

    2012-11-01

    Urban air quality and real human exposure to chemical environmental stressors is an issue of high scientific and political interest. In an effort to find innovative and inexpensive means for air quality monitoring, the ability of car engine air filters (CAFs) to act as efficient samplers collecting street level air, to which people are exposed to, was tested. In particular, in the case of taxis, air filters are replaced after regular distances, the itineraries are almost exclusively urban, cruising mode is similar and, thus, knowledge of the air flow can provide with an integrated city air sample. The present pilot study focused on polycyclic aromatic hydrocarbons (PAHs), the most important category of organic pollutants associated with traffic emissions. Concentrations of ΣPAHs in CAFs ranged between 650 and 2900 μg CAF(-1), with benzo[b]fluoranthene, benzo[k]fluoranthene and indeno[123-cd]pyrene being the most abundant PAHs. Benzo[a]pyrene (BaP) ranged between 110 and 250 μg CAF(-1), accounting regularly for 5-15% of the total carcinogenic PAHs. The CAF PAH loads were used to derive road-level atmospheric PAH concentrations from a standard formula relating to the CAF air flow. Important parameters/assumptions for these estimates are the cruising speed and the exposure duration of each CAF. Based on information obtained from the garage experts, an average 'sampled air volume' of 48,750 m(3) per CAF was estimated, with uncertainty in this calculation estimated to be about a factor of 4 between the two extreme scenarios. Based on this air volume, ΣPAHs ranged between 13 and 56 ng m(-3) and BaP between 2.1 and 5.0 ng m(-3), suggesting that in-traffic BaP concentrations can be many times higher than the limit values set by the UK (0.25 ng m(-3)) and the European Union (1.0 ng m(-3)), or from active sampling stations normally cited on building roof tops or far from city centres. Notwithstanding the limitations of this approach, the very low cost, the continuous

  6. Air Sample Conditioner Helps the Waste Treatment Plant Meet Emissions Standards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Glissmeyer, John A.; Flaherty, Julia E.; Pekour, Mikhail S.

    2014-12-02

    The air in three of the Hanford Site Waste Treatment and Immobilization Plant (WTP) melter off-gas discharge stacks will be hot and humid after passing through the train of emission abatement equipment. The off-gas temperature and humidity levels will be incompatible with the airborne emissions monitoring equipment required for this type of stack. To facilitate sampling from these facilities, an air sample conditioner system will be installed to introduce cool, dry air into the sample stream to reduce the temperature and dew point. This will avoid thermal damage to the instrumentation and problematic condensation. The complete sample transport system mustmore » also deliver at least 50% of the particles in the sample airstream to the sample collection and on-line analysis equipment. The primary components of the sample conditioning system were tested in a laboratory setting. The sample conditioner itself is based on a commercially-available porous tube filter design. It consists of a porous sintered metal tube inside a coaxial metal jacket. The hot gas sample stream passes axially through the porous tube, and the dry, cool air is injected into the jacket and through the porous wall of the inner tube, creating an effective sample diluter. The dilution and sample air mix along the entire length of the porous tube, thereby simultaneously reducing the dew point and temperature of the mixed sample stream. Furthermore, because the dilution air enters through the porous tube wall, the sample stream does not come in contact with the porous wall and particle deposition is reduced in this part of the sampling system. Tests were performed with an environmental chamber to supply air with the temperature and humidity needed to simulate the off-gas conditions. Air from the chamber was passed through the conditioning system to test its ability to reduce the temperature and dew point of the sample stream. To measure particle deposition, oil droplets in the range of 9 to 11

  7. Volatile organic compounds: sampling methods and their worldwide profile in ambient air.

    PubMed

    Kumar, Anuj; Víden, Ivan

    2007-08-01

    The atmosphere is a particularly difficult analytical system because of the very low levels of substances to be analysed, sharp variations in pollutant levels with time and location, differences in wind, temperature and humidity. This makes the selection of an efficient sampling technique for air analysis a key step to reliable results. Generally, methods for volatile organic compounds sampling include collection of the whole air or preconcentration of samples on adsorbents. All the methods vary from each other according to the sampling technique, type of sorbent, method of extraction and identification technique. In this review paper we discuss various important aspects for sampling of volatile organic compounds by the widely used and advanced sampling methods. Characteristics of various adsorbents used for VOCs sampling are also described. Furthermore, this paper makes an effort to comprehensively review the concentration levels of volatile organic compounds along with the methodology used for analysis, in major cities of the world.

  8. Polyurethane foam (PUF) disks passive air samplers: wind effect on sampling rates.

    PubMed

    Tuduri, Ludovic; Harner, Tom; Hung, Hayley

    2006-11-01

    Different passive sampler housings were evaluated for their wind dampening ability and how this might translate to variability in sampler uptake rates. Polyurethane foam (PUF) disk samplers were used as the sampling medium and were exposed to a PCB-contaminated atmosphere in a wind tunnel. The effect of outside wind speed on PUF disk sampling rates was evaluated by exposing polyurethane foam (PUF) disks to a PCB-contaminated air stream in a wind tunnel over air velocities in the range 0 to 1.75 m s-1. PUF disk sampling rates increased gradually over the range 0-0.9 m s-1 at approximately 4.5-14.6 m3 d-1 and then increased sharply to approximately 42 m3 d-1 at approximately 1.75 m s-1 (sum of PCBs). The results indicate that for most field deployments the conventional 'flying saucer' housing adequately dampens the wind effect and will yield approximately time-weighted air concentrations.

  9. Air bubbles and hemolysis of blood samples during transport by pneumatic tube systems.

    PubMed

    Mullins, Garrett R; Bruns, David E

    2017-10-01

    Transport of blood samples through pneumatic tube systems (PTSs) generates air bubbles in transported blood samples and, with increasing duration of transport, the appearance of hemolysis. We investigated the role of air-bubble formation in PTS-induced hemolysis. Air was introduced into blood samples for 0, 1, 3 or 5min to form air bubbles. Hemolysis in the blood was assessed by (H)-index, lactate dehydrogenase (LD) and potassium in plasma. In an effort to prevent PTS-induced hemolysis, blood sample tubes were completely filled, to prevent air bubble formation, and compared with partially filled samples after PTS transport. We also compared hemolysis in anticoagulated vs clotted blood subjected to PTS transport. As with transport through PTSs, the duration of air bubble formation in blood by a gentle stream of air predicted the extent of hemolysis as measured by H-index (p<0.01), LD (p<0.01), and potassium (p<0.02) in plasma. Removing air space in a blood sample prevented bubble formation and fully protected the blood from PTS-induced hemolysis (p<0.02 vs conventionally filled collection tube). Clotted blood developed less foaming during PTS transport and was partially protected from hemolysis vs anticoagulated blood as indicated by lower LD (p<0.03) in serum than in plasma after PTS sample transport. Prevention of air bubble formation in blood samples during PTS transport protects samples from hemolysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Chemical reactivities of ambient air samples in three Southern California communities

    PubMed Central

    Eiguren-Fernandez, Arantza; Di Stefano, Emma; Schmitz, Debra A.; Guarieiro, Aline Lefol Nani; Salinas, Erika M.; Nasser, Elina; Froines, John R.; Cho, Arthur K.

    2015-01-01

    The potential adverse health effects of PM2.5 and vapor samples from three communities that neighbor railyards, Commerce (CM), Long Beach (LB), and San Bernardino (SB), were assessed by determination of chemical reactivities attributed to the induction of oxidative stress by air pollutants. The assays used were dithiothreitol (DTT) and dihydrobenzoic acid (DHBA) based procedures for prooxidant content and a glyceraldehyde-3-phosphate dehydrogenase (GAPDH) assay for electrophiles. Prooxidants and electrophiles have been proposed as the reactive chemical species responsible for the induction of oxidative stress by air pollution mixtures. The PM2.5 samples from CM and LB sites showed seasonal differences in reactivities with higher levels in the winter whereas the SB sample differences were reversed. The reactivities in the vapor samples were all very similar, except for the summer SB samples, which contained higher levels of both prooxidants and electrophiles. The results suggest the observed reactivities reflect general geographical differences rather than direct effects of the railyards. Distributional differences in reactivities were also observed with PM2.5 fractions containing most of the prooxidants (74–81%) and the vapor phase most of the electrophiles (82–96%). The high levels of the vapor phase electrophiles and their potential for adverse biological effects point out the importance of the vapor phase in assessing the potential health effects of ambient air. PMID:25947123

  11. Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

    NASA Technical Reports Server (NTRS)

    Condon, E. P.; Vedder, J. F.

    1984-01-01

    Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

  12. Solubility testing of actinides on breathing-zone and area air samples

    NASA Astrophysics Data System (ADS)

    Metzger, Robert Lawrence

    The solubility of inhaled radionuclides in the human lung is an important characteristic of the compounds needed to perform internal dosimetry assessments for exposed workers. A solubility testing method for uranium and several common actinides has been developed with sufficient sensitivity to allow profiles to be determined from routine breathing zone and area air samples in the workplace. Air samples are covered with a clean filter to form a filter-sample-filter sandwich which is immersed in an extracellular lung serum simulant solution. The sample is moved to a fresh beaker of the lung fluid simulant each day for one week, and then weekly until the end of the 28 day test period. The soak solutions are wet ashed with nitric acid and hydrogen peroxide to destroy the organic components of the lung simulant solution prior to extraction of the nuclides of interest directly into an extractive scintillator for subsequent counting on a Photon-Electron Rejecting Alpha Liquid Scintillation (PERALSsp°ler ) spectrometer. Solvent extraction methods utilizing the extractive scintillators have been developed for the isotopes of uranium, plutonium, and curium. The procedures normally produce an isotopic recovery greater than 95% and have been used to develop solubility profiles from air samples with 40 pCi or less of Usb3Osb8. This makes it possible to characterize solubility profiles in every section of operating facilities where airborne nuclides are found using common breathing zone air samples. The new method was evaluated by analyzing uranium compounds from two uranium mills whose product had been previously analyzed by in vitro solubility testing in the laboratory and in vivo solubility testing in rodents. The new technique compared well with the in vivo rodent solubility profiles. The method was then used to evaluate the solubility profiles in all process sections of an operating in situ uranium plant using breathing zone and area air samples collected during routine

  13. NHEXAS PHASE I MARYLAND STUDY--QA ANALYTICAL RESULTS FOR PESTICIDES IN REPLICATE SAMPLES

    EPA Science Inventory

    The Pesticides in Replicates data set contains the analytical results of measurements of up to 10 pesticides in 68 replicate (duplicate) samples from 41 households. Measurements were made in samples of indoor air, dust, soil, drinking water, food, and beverages. Duplicate sampl...

  14. APPLICATION OF SEMIPERMEABLE MEMBRANE DEVICES TO INDOOR AIR SAMPLING

    EPA Science Inventory

    Semipermeable membrane devices (SPMDs) are a relatively new passive sampling technique for nonpolar organic compounds that have been extensively used for surface water sampling. A small body of literature indicates that SPMDs are also useful for air sampling. Because SPMDs ha...

  15. NHEXAS PHASE I MARYLAND STUDY--QA ANALYTICAL RESULTS FOR METALS IN REPLICATE SAMPLES

    EPA Science Inventory

    The Metals in Replicates data set contains the analytical results of measurements of up to 11 metals in 88 replicate (duplicate) samples from 52 households. Measurements were made in samples of indoor and outdoor air, drinking water, food, and beverages. Duplicate samples for a...

  16. Interferometrically stable, enclosed, spinning sample cell for spectroscopic experiments on air-sensitive samples

    NASA Astrophysics Data System (ADS)

    Baranov, Dmitry; Hill, Robert J.; Ryu, Jisu; Park, Samuel D.; Huerta-Viga, Adriana; Carollo, Alexa R.; Jonas, David M.

    2017-01-01

    In experiments with high photon flux, it is necessary to rapidly remove the sample from the beam and to delay re-excitation until the sample has returned to equilibrium. Rapid and complete sample exchange has been a challenge for air-sensitive samples and for vibration-sensitive experiments. Here, a compact spinning sample cell for air and moisture sensitive liquid and thin film samples is described. The principal parts of the cell are a copper gasket sealed enclosure, a 2.5 in. hard disk drive motor, and a reusable, chemically inert glass sandwich cell. The enclosure provides an oxygen and water free environment at the 1 ppm level, as demonstrated by multi-day tests with sodium benzophenone ketyl radical. Inside the enclosure, the glass sandwich cell spins at ≈70 Hz to generate tangential speeds of 7-12 m/s that enable complete sample exchange at 100 kHz repetition rates. The spinning cell is acoustically silent and compatible with a ±1 nm rms displacement stability interferometer. In order to enable the use of the spinning cell, we discuss centrifugation and how to prevent it, introduce the cycle-averaged resampling rate to characterize repetitive excitation, and develop a figure of merit for a long-lived photoproduct buildup.

  17. Interferometrically stable, enclosed, spinning sample cell for spectroscopic experiments on air-sensitive samples.

    PubMed

    Baranov, Dmitry; Hill, Robert J; Ryu, Jisu; Park, Samuel D; Huerta-Viga, Adriana; Carollo, Alexa R; Jonas, David M

    2017-01-01

    In experiments with high photon flux, it is necessary to rapidly remove the sample from the beam and to delay re-excitation until the sample has returned to equilibrium. Rapid and complete sample exchange has been a challenge for air-sensitive samples and for vibration-sensitive experiments. Here, a compact spinning sample cell for air and moisture sensitive liquid and thin film samples is described. The principal parts of the cell are a copper gasket sealed enclosure, a 2.5 in. hard disk drive motor, and a reusable, chemically inert glass sandwich cell. The enclosure provides an oxygen and water free environment at the 1 ppm level, as demonstrated by multi-day tests with sodium benzophenone ketyl radical. Inside the enclosure, the glass sandwich cell spins at ≈70 Hz to generate tangential speeds of 7-12 m/s that enable complete sample exchange at 100 kHz repetition rates. The spinning cell is acoustically silent and compatible with a ±1 nm rms displacement stability interferometer. In order to enable the use of the spinning cell, we discuss centrifugation and how to prevent it, introduce the cycle-averaged resampling rate to characterize repetitive excitation, and develop a figure of merit for a long-lived photoproduct buildup.

  18. Results of soil, ground-water, surface-water, and streambed-sediment sampling at Air Force Plane 85, Columbus, Ohio, 1996

    USGS Publications Warehouse

    Parnell, J.M.

    1997-01-01

    The U.S. Geological Survey (USGS), in cooperation with Aeronautical Systems Center, Environmental Management Directorate, Restoration Division, prepared the Surface- and Ground- Water Monitoring Work Plan for Air Force Plant 85 (AFP 85 or Plant), Columbus, Ohio, under the Air Force Installation Restoration Program to characterize any ground-water, surface-water, and soil contamination that may exist at AFP 85. The USGS began the study in November 1996. The Plant was divided into nine sampling areas, which included some previously investi gated study sites. The investigation activities included the collection and presentation of data taken during drilling and water-quality sampling. Data collection focused on the saturated and unsatur ated zones and surface water. Twenty-three soil borings were completed. Ten monitoring wells (six existing wells and four newly constructed monitoring wells) were selected for water-quality sam pling. Surface-water and streambed-sediment sampling locations were chosen to monitor flow onto and off of the Plant. Seven sites were sampled for both surface-water and streambed-sediment quality. This report presents data on the selected inorganic and organic constituents in soil, ground water, surface water, and streambed sediments at AFP 85. The methods of data collection and anal ysis also are included. Knowledge of the geologic and hydrologic setting could aid Aeronautical Systems Center, Environmental Management Directorate, Restoration Division, and its governing regulatory agencies in future remediation studies.

  19. NHEXAS PHASE I ARIZONA STUDY--QA ANALYTICAL RESULTS FOR PESTICIDES IN BLANK SAMPLES

    EPA Science Inventory

    The Pesticides in Blank Samples data set contains the analytical results of measurements of up to 4 pesticides in 43 blank samples from 29 households. Measurements were made in blank samples of dust, indoor and outdoor air, food and beverages, blood, urine, and dermal wipe resid...

  20. Determination of methyl bromide in air samples by headspace gas chromatography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woodrow, J.E.; McChesney, M.M.; Seiber, J.N.

    1988-03-01

    Methyl bromide is extensively used in agriculture (4 x 10/sup 6/ kg for 1985 in California alone as a fumigant to control nematodes, weeds, and fungi in soil and insect pests in harvested grains and nuts. Given its low boiling point (3.8/sup 0/C) and high vapor pressure (approx. 1400 Torr at 20/sup 0/C), methyl bromide will readily diffuse if not rigorously contained. Methods for determining methyl bromide and other halocarbons in air vary widely. A common practice is to trap the material from air on an adsorbent, such as polymeric resins, followed by thermal desorption either directly into the analyticalmore » instrumentation or after intermediary cryofocusing. While in some cases analytical detection limits were reasonable (parts per million range), many of the published methods were labor intensive and required special handling techniques that precluded high sample throughput. They describe here a method for the sampling and analysis of airborne methyl bromide that was designed to handle large numbers of samples through automating some critical steps of the analysis. The result was a method that allowed around-the-clock operation with a minimum of operator attention. Furthermore, the method was not specific to methyl bromide and could be used to determine other halocarbons in air.« less

  1. Air exposure and sample storage time influence on hydrogen release from tungsten

    NASA Astrophysics Data System (ADS)

    Moshkunov, K. A.; Schmid, K.; Mayer, M.; Kurnaev, V. A.; Gasparyan, Yu. M.

    2010-09-01

    In investigations of hydrogen retention in first wall components the influence of the conditions of the implanted target storage prior to analysis and the storage time is often neglected. Therefore we have performed a dedicated set of experiments. The release of hydrogen from samples exposed to ambient air after irradiation was compared to samples kept in vacuum. For air exposed samples significant amounts of HDO and D 2O are detected during TDS. Additional experiments have shown that heavy water is formed by recombination of releasing D and H atoms with O on the W surface. This water formation can alter hydrogen retention results significantly, in particular - for low retention cases. In addition to the influence of ambient air exposure also the influence of storage time in vacuum was investigated. After implantation at 300 K the samples were stored in vacuum for up to 1 week during which the retained amount decreased significantly. The subsequently measured TDS spectra showed that D was lost from both the high and low energy peaks during storage at ambient temperature of ˜300 K. An attempt to simulate this release from both peaks during room temperature storage by TMAP 7 calculations showed that this effect cannot be explained by conventional diffusion/trapping models.

  2. Air sampling unit for breath analyzers

    NASA Astrophysics Data System (ADS)

    Szabra, Dariusz; Prokopiuk, Artur; Mikołajczyk, Janusz; Ligor, Tomasz; Buszewski, Bogusław; Bielecki, Zbigniew

    2017-11-01

    The paper presents a portable breath sampling unit (BSU) for human breath analyzers. The developed unit can be used to probe air from the upper airway and alveolar for clinical and science studies. The BSU is able to operate as a patient interface device for most types of breath analyzers. Its main task is to separate and to collect the selected phases of the exhaled air. To monitor the so-called I, II, or III phase and to identify the airflow from the upper and lower parts of the human respiratory system, the unit performs measurements of the exhaled CO2 (ECO2) in the concentration range of 0%-20% (0-150 mm Hg). It can work in both on-line and off-line modes according to American Thoracic Society/European Respiratory Society standards. A Tedlar bag with a volume of 5 dm3 is mounted as a BSU sample container. This volume allows us to collect ca. 1-25 selected breath phases. At the user panel, each step of the unit operation is visualized by LED indicators. This helps us to regulate the natural breathing cycle of the patient. There is also an operator's panel to ensure monitoring and configuration setup of the unit parameters. The operation of the breath sampling unit was preliminarily verified using the gas chromatography/mass spectrometry (GC/MS) laboratory setup. At this setup, volatile organic compounds were extracted by solid phase microextraction. The tests were performed by the comparison of GC/MS signals from both exhaled nitric oxide and isoprene analyses for three breath phases. The functionality of the unit was proven because there was an observed increase in the signal level in the case of the III phase (approximately 40%). The described work made it possible to construct a prototype of a very efficient breath sampling unit dedicated to breath sample analyzers.

  3. Air and smear sample calculational tool for Fluor Hanford Radiological control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    BAUMANN, B.L.

    2003-07-11

    A spreadsheet calculation tool was developed to automate the calculations performed for determining the concentration of airborne radioactivity and smear counting as outlined in HNF-13536, Section 5.2.7, ''Analyzing Air and Smear Samples''. This document reports on the design and testing of the calculation tool. Radiological Control Technicians (RCTs) will save time and reduce hand written and calculation errors by using an electronic form for documenting and calculating work place air samples. Current expectations are RCTs will perform an air sample and collect the filter or perform a smear for surface contamination. RCTs will then survey the filter for gross alphamore » and beta/gamma radioactivity and with the gross counts utilize either hand calculation method or a calculator to determine activity on the filter. The electronic form will allow the RCT with a few key strokes to document the individual's name, payroll, gross counts, instrument identifiers; produce an error free record. This productivity gain is realized by the enhanced ability to perform mathematical calculations electronically (reducing errors) and at the same time, documenting the air sample.« less

  4. Comparison of indoor air sampling and dust collection methods for fungal exposure assessment using quantitative PCR

    EPA Science Inventory

    Evaluating fungal contamination indoors is complicated because of the many different sampling methods utilized. In this study, fungal contamination was evaluated using five sampling methods and four matrices for results. The five sampling methods were a 48 hour indoor air sample ...

  5. Sorbent-based sampling methods for volatile and semi-volatile organic compounds in air Part 1: Sorbent-based air monitoring options.

    PubMed

    Woolfenden, Elizabeth

    2010-04-16

    Sorbent tubes/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in air. Target compounds range in volatility from acetylene and freons to phthalates and PCBs and include apolar, polar and reactive species. Airborne vapour concentrations will vary depending on the nature of the location, nearby pollution sources, weather conditions, etc. Levels can range from low percent concentrations in stack and vent emissions to low part per trillion (ppt) levels in ultra-clean outdoor locations. Hundreds, even thousands of different compounds may be present in any given atmosphere. GC is commonly used in combination with mass spectrometry (MS) detection especially for environmental monitoring or for screening uncharacterised workplace atmospheres. Given the complexity and variability of organic vapours in air, no one sampling approach suits every monitoring scenario. A variety of different sampling strategies and sorbent media have been developed to address specific applications. Key sorbent-based examples include: active (pumped) sampling onto tubes packed with one or more sorbents held at ambient temperature; diffusive (passive) sampling onto sorbent tubes/cartridges; on-line sampling of air/gas streams into cooled sorbent traps; and transfer of air samples from containers (canisters, Tedlar) bags, etc.) into cooled sorbent focusing traps. Whichever sampling approach is selected, subsequent analysis almost always involves either solvent extraction or thermal desorption (TD) prior to GC(/MS) analysis. The overall performance of the air monitoring method will depend heavily on appropriate selection of key sampling and analytical parameters. This comprehensive review of air monitoring using sorbent tubes/traps is divided into 2 parts. (1) Sorbent-based air sampling option. (2) Sorbent selection and other aspects of optimizing sorbent-based air monitoring methods. The paper presents

  6. NHEXAS PHASE I MARYLAND STUDY--QA ANALYTICAL RESULTS FOR METALS IN SPIKE SAMPLES

    EPA Science Inventory

    The Metals in Spikes data set contains the analytical results of measurements of up to 4 metals in 71 control samples (spikes) from 47 households. Measurements were made in samples of indoor and outdoor air, blood, and urine. Controls were used to assess recovery of target anal...

  7. Modeling and Qualification of a Modified Emission Unit for Radioactive Air Emissions Stack Sampling Compliance.

    PubMed

    Barnett, J Matthew; Yu, Xiao-Ying; Recknagle, Kurtis P; Glissmeyer, John A

    2016-11-01

    A planned laboratory space and exhaust system modification to the Pacific Northwest National Laboratory Material Science and Technology Building indicated that a new evaluation of the mixing at the air sampling system location would be required for compliance to ANSI/HPS N13.1-2011. The modified exhaust system would add a third fan, thereby increasing the overall exhaust rate out the stack, thus voiding the previous mixing study. Prior to modifying the radioactive air emissions exhaust system, a three-dimensional computational fluid dynamics computer model was used to evaluate the mixing at the sampling system location. Modeling of the original three-fan system indicated that not all mixing criteria could be met. A second modeling effort was conducted with the addition of an air blender downstream of the confluence of the three fans, which then showed satisfactory mixing results. The final installation included an air blender, and the exhaust system underwent full-scale tests to verify velocity, cyclonic flow, gas, and particulate uniformity. The modeling results and those of the full-scale tests show agreement between each of the evaluated criteria. The use of a computational fluid dynamics code was an effective aid in the design process and allowed the sampling system to remain in its original location while still meeting the requirements for sampling at a well mixed location.

  8. Commander De Winne poses for a photo during Air Sampling

    NASA Image and Video Library

    2009-11-11

    ISS021-E-024700 (11 Nov. 2009) --- European Space Agency astronaut Frank De Winne, Expedition 21 commander, uses the Microbial Air Sampler kit (floating freely near De Winne) to obtain microbiology (bacterial & fungal) air samples in the Kibo laboratory of the International Space Station.

  9. Detection of Mycoplasma hyopneumoniae by Air Sampling with a Nested PCR Assay

    PubMed Central

    Stärk, Katharina D. C.; Nicolet, Jacques; Frey, Joachim

    1998-01-01

    This article describes the first successful detection of airborne Mycoplasma hyopneumoniae under experimental and field conditions with a new nested PCR assay. Air was sampled with polyethersulfone membranes (pore size, 0.2 μm) mounted in filter holders. Filters were processed by dissolution and direct extraction of DNA for PCR analysis. For the PCR, two nested pairs of oligonucleotide primers were designed by using an M. hyopneumoniae-specific DNA sequence of a repeated gene segment. A nested PCR assay was developed and used to analyze samples collected in eight pig houses where respiratory problems had been common. Air was also sampled from a mycoplasma-free herd. The nested PCR was highly specific and 104 times as sensitive as a one-step PCR. Under field conditions, the sampling system was able to detect airborne M. hyopneumoniae on 80% of farms where acute respiratory disease was present. No airborne M. hyopneumoniae was detected on infected farms without acute cases. The chance of successful detection was increased if air was sampled at several locations within a room and at a lower air humidity. PMID:9464391

  10. Air sampling procedures to evaluate microbial contamination: a comparison between active and passive methods in operating theatres

    PubMed Central

    2012-01-01

    Background Since air can play a central role as a reservoir for microorganisms, in controlled environments such as operating theatres regular microbial monitoring is useful to measure air quality and identify critical situations. The aim of this study is to assess microbial contamination levels in operating theatres using both an active and a passive sampling method and then to assess if there is a correlation between the results of the two different sampling methods. Methods The study was performed in 32 turbulent air flow operating theatres of a University Hospital in Southern Italy. Active sampling was carried out using the Surface Air System and passive sampling with settle plates, in accordance with ISO 14698. The Total Viable Count (TVC) was evaluated at rest (in the morning before the beginning of surgical activity) and in operational (during surgery). Results The mean TVC at rest was 12.4 CFU/m3 and 722.5 CFU/m2/h for active and passive samplings respectively. The mean in operational TVC was 93.8 CFU/m3 (SD = 52.69; range = 22-256) and 10496.5 CFU/m2/h (SD = 7460.5; range = 1415.5-25479.7) for active and passive samplings respectively. Statistical analysis confirmed that the two methods correlate in a comparable way with the quality of air. Conclusion It is possible to conclude that both methods can be used for general monitoring of air contamination, such as routine surveillance programs. However, the choice must be made between one or the other to obtain specific information. PMID:22853006

  11. Scheduling whole-air samples above the Trade Wind Inversion from SUAS using real-time sensors

    NASA Astrophysics Data System (ADS)

    Freer, J. E.; Greatwood, C.; Thomas, R.; Richardson, T.; Brownlow, R.; Lowry, D.; MacKenzie, A. R.; Nisbet, E. G.

    2015-12-01

    Small Unmanned Air Systems (SUAS) are increasingly being used in science applications for a range of applications. Here we explore their use to schedule the sampling of air masses up to 2.5km above ground using computer controlled bespoked Octocopter platforms. Whole-air sampling is targeted above, within and below the Trade Wind Inversion (TWI). On-board sensors profiled the TWI characteristics in real time on ascent and, hence, guided the altitudes at which samples were taken on descent. The science driver for this research is investigation of the Southern Methane Anomaly and, more broadly, the hemispheric-scale transport of long-lived atmospheric tracers in the remote troposphere. Here we focus on the practical application of SUAS for this purpose. Highlighting the need for mission planning, computer control, onboard sensors and logistics in deploying such technologies for out of line-of-sight applications. We show how such a platform can be deployed successfully, resulting in some 60 sampling flights within a 10 day period. Challenges remain regarding the deployment of such platforms routinely and cost-effectively, particularly regarding training and support. We present some initial results from the methane sampling and its implication for exploring and understanding the Southern Methane Anomaly.

  12. Contemporary-use pesticides in personal air samples during pregnancy and blood samples at delivery among urban minority mothers and newborns.

    PubMed Central

    Whyatt, Robin M; Barr, Dana B; Camann, David E; Kinney, Patrick L; Barr, John R; Andrews, Howard F; Hoepner, Lori A; Garfinkel, Robin; Hazi, Yair; Reyes, Andria; Ramirez, Judyth; Cosme, Yesenia; Perera, Frederica P

    2003-01-01

    We have measured 29 pesticides in plasma samples collected at birth between 1998 and 2001 from 230 mother and newborn pairs enrolled in the Columbia Center for Children's Environmental Health prospective cohort study. Our prior research has shown widespread pesticide use during pregnancy among this urban minority cohort from New York City. We also measured eight pesticides in 48-hr personal air samples collected from the mothers during pregnancy. The following seven pesticides were detected in 48-83% of plasma samples (range, 1-270 pg/g): the organophosphates chlorpyrifos and diazinon, the carbamates bendiocarb and 2-isopropoxyphenol (metabolite of propoxur), and the fungicides dicloran, phthalimide (metabolite of folpet and captan), and tetrahydrophthalimide (metabolite of captan and captafol). Maternal and cord plasma levels were similar and, except for phthalimide, were highly correlated (p < 0.001). Chlorpyrifos, diazinon, and propoxur were detected in 100% of personal air samples (range, 0.7-6,010 ng/m(3)). Diazinon and propoxur levels were significantly higher in the personal air of women reporting use of an exterminator, can sprays, and/or pest bombs during pregnancy compared with women reporting no pesticide use or use of lower toxicity methods only. A significant correlation was seen between personal air level of chlorpyrifos, diazinon, and propoxur and levels of these insecticides or their metabolites in plasma samples (maternal and/or cord, p < 0.05). The fungicide ortho-phenylphenol was also detected in 100% of air samples but was not measured in plasma. The remaining 22 pesticides were detected in 0-45% of air or plasma samples. Chlorpyrifos, diazinon, propoxur, and bendiocarb levels in air and/or plasma decreased significantly between 1998 and 2001. Findings indicate that pesticide exposures are frequent but decreasing and that the pesticides are readily transferred to the developing fetus during pregnancy. PMID:12727605

  13. Airborne detection and quantification of swine influenza a virus in air samples collected inside, outside and downwind from swine barns.

    PubMed

    Corzo, Cesar A; Culhane, Marie; Dee, Scott; Morrison, Robert B; Torremorell, Montserrat

    2013-01-01

    Airborne transmission of influenza A virus (IAV) in swine is speculated to be an important route of virus dissemination, but data are scarce. This study attempted to detect and quantify airborne IAV by virus isolation and RRT-PCR in air samples collected under field conditions. This was accomplished by collecting air samples from four acutely infected pig farms and locating air samplers inside the barns, at the external exhaust fans and downwind from the farms at distances up to 2.1 km. IAV was detected in air samples collected in 3 out of 4 farms included in the study. Isolation of IAV was possible from air samples collected inside the barn at two of the farms and in one farm from the exhausted air. Between 13% and 100% of samples collected inside the barns tested RRT-PCR positive with an average viral load of 3.20E+05 IAV RNA copies/m³ of air. Percentage of exhaust positive air samples also ranged between 13% and 100% with an average viral load of 1.79E+04 RNA copies/m³ of air. Influenza virus RNA was detected in air samples collected between 1.5 and 2.1 Km away from the farms with viral levels significantly lower at 4.65E+03 RNA copies/m³. H1N1, H1N2 and H3N2 subtypes were detected in the air samples and the hemagglutinin gene sequences identified in the swine samples matched those in aerosols providing evidence that the viruses detected in the aerosols originated from the pigs in the farms under study. Overall our results indicate that pigs can be a source of IAV infectious aerosols and that these aerosols can be exhausted from pig barns and be transported downwind. The results from this study provide evidence of the risk of aerosol transmission in pigs under field conditions.

  14. Airborne Detection and Quantification of Swine Influenza A Virus in Air Samples Collected Inside, Outside and Downwind from Swine Barns

    PubMed Central

    Corzo, Cesar A.; Culhane, Marie; Dee, Scott; Morrison, Robert B.; Torremorell, Montserrat

    2013-01-01

    Airborne transmission of influenza A virus (IAV) in swine is speculated to be an important route of virus dissemination, but data are scarce. This study attempted to detect and quantify airborne IAV by virus isolation and RRT-PCR in air samples collected under field conditions. This was accomplished by collecting air samples from four acutely infected pig farms and locating air samplers inside the barns, at the external exhaust fans and downwind from the farms at distances up to 2.1 km. IAV was detected in air samples collected in 3 out of 4 farms included in the study. Isolation of IAV was possible from air samples collected inside the barn at two of the farms and in one farm from the exhausted air. Between 13% and 100% of samples collected inside the barns tested RRT-PCR positive with an average viral load of 3.20E+05 IAV RNA copies/m3 of air. Percentage of exhaust positive air samples also ranged between 13% and 100% with an average viral load of 1.79E+04 RNA copies/m3 of air. Influenza virus RNA was detected in air samples collected between 1.5 and 2.1 Km away from the farms with viral levels significantly lower at 4.65E+03 RNA copies/m3. H1N1, H1N2 and H3N2 subtypes were detected in the air samples and the hemagglutinin gene sequences identified in the swine samples matched those in aerosols providing evidence that the viruses detected in the aerosols originated from the pigs in the farms under study. Overall our results indicate that pigs can be a source of IAV infectious aerosols and that these aerosols can be exhausted from pig barns and be transported downwind. The results from this study provide evidence of the risk of aerosol transmission in pigs under field conditions. PMID:23951164

  15. Profiling quinones in ambient air samples collected from the Athabasca region (Canada).

    PubMed

    Wnorowski, Andrzej; Charland, Jean-Pierre

    2017-12-01

    This paper presents new findings on polycyclic aromatic hydrocarbon oxidation products-quinones that were collected in ambient air samples in the proximity of oil sands exploration. Quinones were characterized for their diurnal concentration variability, phase partitioning, and molecular size distribution. Gas-phase (GP) and particle-phase (PM) ambient air samples were collected separately in the summer; a lower quinone content was observed in the PM samples from continuous 24-h sampling than from combined 12-h sampling (day and night). The daytime/nocturnal samples demonstrated that nighttime conditions led to lower concentrations and some quinones not being detected. The highest quinone levels were associated with wind directions originating from oil sands exploration sites. The statistical correlation with primary pollutants directly emitted from oil sands industrial activities indicated that the bulk of the detected quinones did not originate directly from primary emission sources and that quinone formation paralleled a reduction in primary source NO x levels. This suggests a secondary chemical transformation of primary pollutants as the origin of the determined quinones. Measurements of 19 quinones included five that have not previously been reported in ambient air or in Standard Reference Material 1649a/1649b and seven that have not been previously measured in ambient air in the underivatized form. This is the first paper to report on quinone characterization in secondary organic aerosols originating from oil sands activities, to distinguish chrysenequinone and anthraquinone positional isomers in ambient air, and to report the requirement of daylight conditions for benzo[a]pyrenequinone and naphthacenequinone to be present in ambient air. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  16. Results from Geothermal Logging, Air and Core-Water Chemistry Sampling, Air Injection Testing and Tracer Testing in the Northern Ghost Dance Fault, YUCCA Mountain, Nevada, November 1996 to August 1998

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lecain, G.D.; Anna, L.O.; Fahy, M.F.

    1998-08-01

    Geothermal logging, air and core-water chemistry sampling, air-injection testing, and tracer testing were done in the northern Ghost Dance Fault at Yucca Mountain, Nevada, from November 1996 to August 1998. The study was done by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy. The fault-testing drill room and test boreholes were located in the crystal-poor, middle nonlithophysal zone of the Topopah Spring Tuff, a tuff deposit of Miocene age. The drill room is located off the Yucca Mountain underground Exploratory Studies Facility at about 230 meters below ground surface. Borehole geothermal logging identified a temperature decreasemore » of 0.1 degree Celsius near the Ghost Dance Fault. The temperature decrease could indicate movement of cooler air or water, or both, down the fault, or it may be due to drilling-induced evaporative or adiabatic cooling. In-situ pneumatic pressure monitoring indicated that barometric pressure changes were transmitted from the ground surface to depth through the Ghost Dance Fault. Values of carbon dioxide and delta carbon-13 from gas samples indicated that air from the underground drill room had penetrated the tuff, supporting the concept of a well-developed fracture system. Uncorrected carbon-14-age estimates from gas samples ranged from 2,400 to 4,500 years. Tritium levels in borehole core water indicated that the fault may have been a conduit for the transport of water from the ground surface to depth during the last 100 years.« less

  17. Portable XRF analysis of occupational air filter samples from different workplaces using different samplers: final results, summary and conclusions.

    PubMed

    Harper, Martin; Pacolay, Bruce; Hintz, Patrick; Bartley, David L; Slaven, James E; Andrew, Michael E

    2007-11-01

    This paper concludes a five-year program on research into the use of a portable X-ray fluorescence (XRF) analyzer for analyzing lead in air sampling filters from different industrial environments, including mining, manufacturing and recycling. The results from four of these environments have already been reported. The results from two additional metal processes are presented here. At both of these sites, lead was a minor component of the total airborne metals and interferences from other elements were minimal. Nevertheless, only results from the three sites where lead was the most abundant metal were used in the overall calculation of method accuracy. The XRF analyzer was used to interrogate the filters, which were then subjected to acid digestion and analysis by inductively-coupled plasma optical-emission spectroscopy (ICP-OES). The filter samples were collected using different filter-holders or "samplers" where the size (diameter), depth and homogeneity of aerosol deposit varied from sampler to sampler. The aerosol collection efficiencies of the samplers were expected to differ, especially for larger particles. The distribution of particles once having entered the sampler was also expected to differ between samplers. Samplers were paired to allow the between-sampler variability to be addressed, and, in some cases, internal sampler wall deposits were evaluated and compared to the filter catch. It was found, rather surprisingly, that analysis of the filter deposits (by ICP-OES) of all the samplers gave equivalent results. It was also found that deposits on some of the sampler walls, which in some protocols are considered part of the sample, could be significant in comparison to the filter deposit. If it is concluded that wall-deposits should be analyzed, then XRF analysis of the filter can only give a minimum estimate of the concentration. Techniques for the statistical analysis of field data were also developed as part of this program and have been reported

  18. Composition Alteration of Stratospheric Air Due to Sampling through a Flow Tube.

    DTIC Science & Technology

    1984-02-03

    C. C. , Forsberg, C. A. , and Pieri , H. V. (19)83) Stratospheric N 20 CF2 Cl and CFCI3 composition studies utilizing in situ cryogenic whole air...Gas-Surface Interactions in Cryogenic Whole Air Sampling, AFGL-TR-81-0162, AD A108255. 19. Gallagher, C. C., Forsberg, C. A., and Pieri , R. V. (1983...Gallagher, C. C., Forsberg, C. A., Pieri , R. V., and Faucher, G. A. (1983a) Oxides of Nitrogen Content of Whole Air Samples Obtained at Altitudes From 12

  19. A persisting secondhand smoke hazard in urban public places: results from fine particulate (PM2.5) air sampling.

    PubMed

    Wilson, Nick; Edwards, Richard; Parry, Rhys

    2011-03-04

    To assess the need for additional smokefree settings, by measuring secondhand smoke (SHS) in a range of public places in an urban setting. Measurements were made in Wellington City during the 6-year period after the implementation of legislation that made indoor areas of restaurants and bars/pubs smokefree in December 2004, and up to 20 years after the 1990 legislation making most indoor workplaces smokefree. Fine particulate levels (PM2.5) were measured with a portable real-time airborne particle monitor. We collated data from our previously published work involving random sampling, purposeful sampling and convenience sampling of a wide range of settings (in 2006) and from additional sampling of selected indoor and outdoor areas (in 2007-2008 and 2010). The "outdoor" smoking areas of hospitality venues had the highest particulate levels, with a mean value of 72 mcg/m3 (range of maximum values 51-284 mcg/m3) (n=20 sampling periods). These levels are likely to create health hazards for some workers and patrons (i.e., when considered in relation to the WHO air quality guidelines). National survey data also indicate that these venues are the ones where SHS exposure is most frequently reported by non-smokers. Areas inside bars that were adjacent to "outdoor" smoking areas also had high levels, with a mean of 54 mcg/m3 (range of maximum values: 18-239 mcg/m3, for n=13 measurements). In all other settings mean levels were lower (means: 2-22 mcg/m3). These other settings included inside traditional style pubs/sports bars (n=10), bars (n=18), restaurants (n=9), cafes (n=5), inside public buildings (n=15), inside transportation settings (n=15), and various outdoor street/park settings (n=22). During the data collection in all settings made smokefree by law, there was only one occasion of a person observed smoking. The results suggest that compliance in pubs/bars and restaurants has remained extremely high in this city in the nearly six years since implementation of the

  20. Passive air sampling of organochlorine pesticides in Mexico.

    PubMed

    Wong, Fiona; Alegria, Henry A; Bidleman, Terry F; Alvarado, Víctor; Angeles, Felipe; Galarza, Alfredo Avila; Bandala, Erick R; Hinojosa, Idolina de la Cerda; Estrada, Ignacio Galindo; Reyes, Guillermo Galindo; Gold-Bouchot, Gerardo; Zamora, Jose Vinicio Macías; Murguía-González, Joaquín; Espinoza, Elias Ramirez

    2009-02-01

    The spatial and temporal variation of organochlorine pesticides (OCs) in air across Mexico was investigated by deploying passive samplers at eleven stations across the country during 2005-2006. Integrated samples were taken over three-month periods and quantified for DDT compounds, endosulfans, toxaphenes, components of technical chlordane, hexachlorocyclohexanes (HCHs), and dieldrin. Enantiomers of chiral chlordanes and o,p'-DDT were determined on chiral stationary phase columns as an indicator of source and age. Results are discussed in combination with pumped air samples taken at four other stations in southern Mexico during 2002-2004. DDT and its metabolites, endosulfan and toxaphene were the most abundant OCs detected in all sampling sites. Atmospheric concentrations of SigmaDDT (p,p'-DDT + o,p'-DDT + p,p'-DDE + o,p'-DDE + p,p'-DDD + o,p'-DDD) ranged from 15 to 2360 pg m(-3) with the highest concentrations found in southern Mexico and the lowest found in northern and central Mexico. A fresher DDT residue was observed at sites with greater DDT use and in the southern part of the country, as shown from the higher FDDTe = p,p'-DDT/(p,p'-DDT + p,p'-DDE) and nearly racemic o,p'-DDT. This agrees with the former heavy use of DDT in the endemic malarious area of the country. A local hotspot of endosulfan was identified at an agricultural area in Mazatlan, Sinaloa, with a annual mean concentration of SigmaENDO (endosulfans I + II + endosulfan sulfate) = 26,800 pg m(-3). At this site, higher concentrations of SigmaENDO were recorded during the winter (November to February) and spring (February to May) periods. From back trajectory analysis, this coincides with a shift in the air mass coming from the Pacific Ocean (May to November) to the inland agricultural area (November to May). The elevated SigmaENDO observed is likely due to the local agricultural usage. HCHs, chlordanes, transnonachlors, and dieldrin were more evenly distributed across the country likely due to

  1. [Legionella spp. contamination in indoor air: preliminary results of an Italian multicenter study].

    PubMed

    Montagna, Maria Teresa; De Giglio, Osvalda; Napoli, Christian; Cannova, Lucia; Cristina, Maria Luisa; Deriu, Maria Grazia; Delia, Santi Antonino; Giuliano, Ada; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Mura, Ida; Pennino, Francesca; Rossini, Angelo; Tardivo, Stefano; Torre, Ida; Torregrossa, Maria Valeria; Villafrate, Maria Rosaria; Albertini, Roberto; Pasquarella, Cesira

    2014-01-01

    To propose a standardized protocol for the evaluation of Legionella contamination in air. A bathroom having a Legionella contamination in water >1,000 cfu/l was selected in 10 different healthcare facilities. Air contamination was assessed by active (Surface Air System, SAS) and passive (Index of Microbial Air, IMA) sampling for 8 hours, about 1 m away from the floor and 50 cm from the tap water. Two hundred liters of air were sampled by SAS every 12 min, after flushing water for 2 min. The IMA value was calculated as the mean value of colony forming units/16 plates exposed during sampling (2 plates/hour). Water contamination was evaluated at T0, after 4 and 8 hours, according to the standard methods. Air contamination by Legionella was found in three healthcare facilities (one with active and two with passive sampling), showing a concomitant tap water contamination (median=40,000; range 1,100-43,000 cfu/l). The remaining seven hospitals isolated Legionella spp. exclusively from water samples (median=8,000; range 1,200-70,000 cfu/l). Our data suggest that environmental Legionella contamination cannot be assessed only through the air sampling, even in the presence of an important water contamination.

  2. Avian influenza H9N2 virus isolated from air samples in LPMs in Jiangxi, China.

    PubMed

    Zeng, Xiaoxu; Liu, Mingbin; Zhang, Heng; Wu, Jingwen; Zhao, Xiang; Chen, Wenbing; Yang, Lei; He, Fenglan; Fan, Guoyin; Wang, Dayan; Chen, Haiying; Shu, Yuelong

    2017-07-24

    Recently, avian influenza virus has caused repeated worldwide outbreaks in humans. Live Poultry Markets (LPMs) play an important role in the circulation and reassortment of novel Avian Influenza Virus (AIVs). Aerosol transmission is one of the most important pathways for influenza virus to spread among poultry, from poultry to mammals, and among mammals. In this study, air samples were collected from LPMs in Nanchang city between April 2014 and March 2015 to investigate possible aerosol transmission of AIVs. Air samples were detected for Flu A by Real-Time Reverse Transcription-Polymerase Chain Reaction (RRT-PCR). If samples were positive for Flu A, they were inoculated into 9- to 10-day-old specific-pathogen-free embryonated eggs. If the result was positive, the whole genome of the virus was sequenced by MiSeq. Phylogenetic trees of all 8 segments were constructed using MEGA 6.05 software. To investigate the possible aerosol transmission of AIVs, 807 air samples were collected from LPMs in Nanchang city between April 2014 and March 2015. Based on RRT-PCR results, 275 samples (34.1%) were Flu A positive, and one virus was successfully isolated with embryonated eggs. The virus shared high nucleotide homology with H9N2 AIVs from South China. Our study provides further evidence that the air in LPMs can be contaminated by influenza viruses and their nucleic acids, and this should be considered when choosing and evaluating disinfection strategies in LPMs, such as regular air disinfection. Aerosolized viruses such as the H9N2 virus detected in this study can increase the risk of human infection when people are exposed in LPMs.

  3. Evaluation of Urban Air Quality By Passive Sampling Technique

    NASA Astrophysics Data System (ADS)

    Nunes, T. V.; Miranda, A. I.; Duarte, S.; Lima, M. J.

    Aveiro is a flat small city in the centre of Portugal, close to the Atlantic coast. In the last two decades an intensive development of demographic, traffic and industry growth in the region was observed which was reflected on the air quality degrada- tion. In order to evaluate the urban air quality in Aveiro, a field-monitoring network by passive sampling with high space resolution was implemented. Twenty-four field places were distributed in a area of 3x3 Km2 and ozone and NO2 concentrations were measured. The site distribution density was higher in the centre, 250x250 m2 than in periphery where a 500x500 m2 grid was used. The selection of field places took into consideration the choice criteria recommendation by United Kingdom environmental authorities, and three tubes and a blank tube for each pollutant were used at each site. The sampling system was mounted at 3m from the ground usually profiting the street lampposts. Concerning NO2 acrylic tubes were used with 85 mm of length and an in- ternal diameter of 12mm, where in one of the extremities three steel grids impregnated with a solution of TEA were placed and fixed with a polyethylene end cup (Heal et al., 1999); PFA Teflon tube with 53 mm of length and 9 mm of internal diameter and three impregnated glass filters impregnated with DPE solution fixed by a teflon end cup was used for ozone sampling (Monn and Hargartner, 1990). The passive sampling method for ozone and nitrogen dioxide was compared with continuous measurements, but the amount of measurements wasnSt enough for an accurate calibration and validation of the method. Although this constraint the field observations (June to August 2001) for these two pollutants assign interesting information about the air quality in the urban area. A krigger method of interpolation (Surfer- Golden Software-2000) was applied to field data to obtain isolines distribution of NO2 and ozone concentration for the studied area. Even the used passive sampling method has many

  4. Monte Carlo simulation of air sampling methods for the measurement of radon decay products.

    PubMed

    Sima, Octavian; Luca, Aurelian; Sahagia, Maria

    2017-08-01

    A stochastic model of the processes involved in the measurement of the activity of the 222 Rn decay products was developed. The distributions of the relevant factors, including air sampling and radionuclide collection, are propagated using Monte Carlo simulation to the final distribution of the measurement results. The uncertainties of the 222 Rn decay products concentrations in the air are realistically evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Sorbent-based sampling methods for volatile and semi-volatile organic compounds in air. Part 2. Sorbent selection and other aspects of optimizing air monitoring methods.

    PubMed

    Woolfenden, Elizabeth

    2010-04-16

    Sorbent tubes/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in air. Applications range from atmospheric research and ambient air monitoring (indoor and outdoor) to occupational hygiene (personal exposure assessment) and measuring chemical emission levels. Part 1 of this paper reviewed the main sorbent-based air sampling strategies including active (pumped) tube monitoring, diffusive (passive) sampling onto sorbent tubes/cartridges plus sorbent trapping/focusing of whole air samples that are either collected in containers (such as canisters or bags) or monitored online. Options for subsequent extraction and transfer to GC(MS) analysis were also summarised and the trend to thermal desorption (TD)-based methods and away from solvent extraction was explained. As a result of this trend, demand for TD-compatible sorbents (alternatives to traditional charcoal) is growing. Part 2 of this paper therefore continues with a summary of TD-compatible sorbents, their respective advantages and limitations and considerations for sorbent selection. Other analytical considerations for optimizing sorbent-based air monitoring methods are also discussed together with recent technical developments and sampling accessories which have extended the application range of sorbent trapping technology generally. Copyright 2010 Elsevier B.V. All rights reserved.

  6. Urban-air-toxics Monitoring Program carbonyl results, 1990

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1991-07-01

    The report summarizes the results of sampling ambient air for selected carbonyl containing compounds in 12 urban centers in the contiguous United States as part of the Urban Air Toxics Monitoring Program (UATMP). Formaldehyde, acetaldehyde, and acetone concentrations were measured using 2,4-dinitrophenylhydrazine (DNPH)-coated silica cartridges to collect the carbonyls for subsequent analysis. Sampling and analysis followed guidance provided in U.S. Environmental Protection Agency (EPA) compendium method TO-11. Formaldehyde concentrations ranged from 0.42 to 34.5 ppbv with an average concentration for all sites of 4.2 ppbv. Site average formaldehyde concentrations ranged from 1.5 ppbv for Houston, TX (H1TX) to 7.9 formore » Washington, DC (W2DC). Acetaldehyde concentrations ranged from 0.37 to 9.5 ppbv, averaging 1.7 ppbv over all 1990 UATMP sites. Site average acetaldehyde concentrations ranged from 0.76 ppbv at Houston, TX (H1TX) to 2.5 ppbv at Baton Rouge, LA (BRLA). Acetone concentrations ranged from 0.37 to 10.8 ppbv and averaged 1.8 ppbv over all sites. Site average acetone concentrations ranged from 0.68 ppbv at Houston, TX (H1TX) to 2.9 ppbv at Chicago, IL (C4IL).« less

  7. Air sampling procedures to evaluate microbial contamination: a comparison between active and passive methods in operating theatres.

    PubMed

    Napoli, Christian; Marcotrigiano, Vincenzo; Montagna, Maria Teresa

    2012-08-02

    Since air can play a central role as a reservoir for microorganisms, in controlled environments such as operating theatres regular microbial monitoring is useful to measure air quality and identify critical situations. The aim of this study is to assess microbial contamination levels in operating theatres using both an active and a passive sampling method and then to assess if there is a correlation between the results of the two different sampling methods. The study was performed in 32 turbulent air flow operating theatres of a University Hospital in Southern Italy. Active sampling was carried out using the Surface Air System and passive sampling with settle plates, in accordance with ISO 14698. The Total Viable Count (TVC) was evaluated at rest (in the morning before the beginning of surgical activity) and in operational (during surgery). The mean TVC at rest was 12.4 CFU/m3 and 722.5 CFU/m2/h for active and passive samplings respectively. The mean in operational TVC was 93.8 CFU/m3 (SD = 52.69; range = 22-256) and 10496.5 CFU/m2/h (SD = 7460.5; range = 1415.5-25479.7) for active and passive samplings respectively. Statistical analysis confirmed that the two methods correlate in a comparable way with the quality of air. It is possible to conclude that both methods can be used for general monitoring of air contamination, such as routine surveillance programs. However, the choice must be made between one or the other to obtain specific information.

  8. U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--QA ANALYTICAL RESULTS FOR METALS IN BLANK SAMPLES

    EPA Science Inventory

    The Metals in Blank Samples data set contains the analytical results of measurements of up to 27 metals in 52 blank samples. Measurements were made in blank samples of dust, indoor air, food, water, and dermal wipe residue. Blank samples were used to assess the potential for sa...

  9. Use of Whatman-41 filters in air quality sampling networks (with applications to elemental analysis)

    NASA Technical Reports Server (NTRS)

    Neustadter, H. E.; Sidik, S. M.; King, R. B.; Fordyce, J. S.; Burr, J. C.

    1974-01-01

    The operation of a 16-site parallel high volume air sampling network with glass fiber filters on one unit and Whatman-41 filters on the other is reported. The network data and data from several other experiments indicate that (1) Sampler-to-sampler and filter-to-filter variabilities are small; (2) hygroscopic affinity of Whatman-41 filters need not introduce errors; and (3) suspended particulate samples from glass fiber filters averaged slightly, but not statistically significantly, higher than from Whatman-41-filters. The results obtained demonstrate the practicability of Whatman-41 filters for air quality monitoring and elemental analysis.

  10. High-throughput liquid-absorption air-sampling apparatus and methods

    DOEpatents

    Zaromb, Solomon

    2000-01-01

    A portable high-throughput liquid-absorption air sampler [PHTLAAS] has an asymmetric air inlet through which air is drawn upward by a small and light-weight centrifugal fan driven by a direct current motor that can be powered by a battery. The air inlet is so configured as to impart both rotational and downward components of motion to the sampled air near said inlet. The PHTLAAS comprises a glass tube of relatively small size through which air passes at a high rate in a swirling, highly turbulent motion, which facilitates rapid transfer of vapors and particulates to a liquid film covering the inner walls of the tube. The pressure drop through the glass tube is <10 cm of water, usually <5 cm of water. The sampler's collection efficiency is usually >20% for vapors or airborne particulates in the 2-3.mu. range and >50% for particles larger than 4.mu.. In conjunction with various analyzers, the PHTLAAS can serve to monitor a variety of hazardous or illicit airborne substances, such as lead-containing particulates, tritiated water vapor, biological aerosols, or traces of concealed drugs or explosives.

  11. Air Sampling Logbook of Region 4 Yellow Bluff Air Study Wilcox County, Alabama SESD Project Identification Number:11-0068

    EPA Pesticide Factsheets

    Contains the Air Sampling Logbook between 1-24-2011 thru 1-28-2011 from the Region 4 Yellow Bluff Air Study Wilcox County, Alabama SESD Project Identification Number:11-0068 November 2010-December 2010

  12. Occurrence and quantitative microbial risk assessment of Cryptosporidium and Giardia in soil and air samples.

    PubMed

    Balderrama-Carmona, Ana Paola; Gortáres-Moroyoqui, Pablo; Álvarez-Valencia, Luis Humberto; Castro-Espinoza, Luciano; Mondaca-Fernández, Iram; Balderas-Cortés, José de Jesús; Chaidez-Quiroz, Cristóbal; Meza-Montenegro, María Mercedes

    2014-09-01

    Cryptosporidium oocysts and Giardia cysts can be transmitted by the fecal-oral route and may cause gastrointestinal parasitic zoonoses. These zoonoses are common in rural zones due to the parasites being harbored in fecally contaminated soil. This study assessed the risk of illness (giardiasis and cryptosporidiosis) from inhaling and/or ingesting soil and/or airborne dust in Potam, Mexico. To assess the risk of infection, Quantitative Microbial Risk Assessment (QMRA) was employed, with the following steps: (1) hazard identification, (2) hazard exposure, (3) dose-response, and (4) risk characterization. Cryptosporidium oocysts and Giardia cysts were observed in 52% and 57%, respectively, of total soil samples (n=21), and in 60% and 80%, respectively, of air samples (n=12). The calculated annual risks were higher than 9.9 × 10(-1) for both parasites in both types of sample. Soil and air inhalation and/or ingestion are important vehicles for these parasites. To our knowledge, the results obtained in the present study represent the first QMRAs for cryptosporidiosis and giardiasis due to soil and air inhalation/ingestion in Mexico. In addition, this is the first evidence of the microbial air quality around these parasites in rural zones. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Whole air canister sampling coupled with preconcentration GC/MS analysis of part-per-trillion levels of trimethylsilanol in semiconductor cleanroom air.

    PubMed

    Herrington, Jason S

    2013-08-20

    The costly damage airborne trimethylsilanol (TMS) exacts on optics in the semiconductor industry has resulted in the demand for accurate and reliable methods for measuring TMS at trace levels (i.e., parts per trillion, volume per volume of air [ppt(v)] [~ng/m(3)]). In this study I developed a whole air canister-based approach for field sampling trimethylsilanol in air, as well as a preconcentration gas chromatography/mass spectrometry laboratory method for analysis. The results demonstrate clean canister blanks (0.06 ppt(v) [0.24 ng/m(3)], which is below the detection limit), excellent linearity (a calibration relative response factor relative standard deviation [RSD] of 9.8%) over a wide dynamic mass range (1-100 ppt(v)), recovery/accuracy of 93%, a low selected ion monitoring method detection limit of 0.12 ppt(v) (0.48 ng/m(3)), replicate precision of 6.8% RSD, and stability (84% recovery) out to four days of storage at room temperature. Samples collected at two silicon wafer fabrication facilities ranged from 10.0 to 9120 ppt(v) TMS and appear to be associated with the use of hexamethyldisilazane priming agent. This method will enable semiconductor cleanroom managers to monitor and control for trace levels of trimethylsilanol.

  14. Atmospheric Methane Mixing Ratios--The NOAA/CMDL Global Cooperative Air Sampling Network\\, 1983-1993

    DOE Data Explorer

    Dlugokencky, E. J. [National Oceanic and Atmospheric Administration, Boulder, Colorado (USA); Lang, P. M. [National Oceanic and Atmospheric Administration, Boulder, Colorado (USA); Masarie, K. A. [National Oceanic and Atmospheric Administration, Boulder, Colorado (USA); Steele, L. P. [Commonwealth Scientific and Industrial Research Organisation, Aspendale, Victoria, Australia

    1994-01-01

    This data base presents atmospheric methane (CH4) mixing ratios from flask air samples collected over the period 1983-1993 by the National Oceanic and Atmospheric Administration, Climate Monitoring and Diagnostics Laboratory's (NOAA/CMDL's) global cooperative air sampling network. Air samples were collected approximately once per week at 44 fixed sites (37 of which were still active at the end of 1993). Samples were also collected at 5 degree latitude intervals along shipboard cruise tracks in the Pacific Ocean between North America and New Zealand (or Australia) and at 3 degree latitude intervals along cruise tracks in the South China Sea between Singapore and Hong Kong. The shipboard measurements were made approximately every 3 weeks per latitude zone by each of two ships in the Pacific Ocean and approximately once every week per latitude zone in the South China Sea. All samples were analyzed for CH4 at the NOAA/CMDL laboratory in Boulder, Colorado, by gas chromatography with flame ionization detection, and each aliquot was referenced to the NOAA/CMDL methane standard scale. In addition to providing the complete set of atmospheric CH4 measurements from flask air samples collected at the NOAA/CMDL network sites, this data base also includes files which list monthly mean mixing ratios derived from the individual flask air measurements. These monthly summary data are available for 35 of the fixed sites and 21 of the shipboard sampling sites.

  15. Curve fitting air sample filter decay curves to estimate transuranic content.

    PubMed

    Hayes, Robert B; Chiou, Hung Cheng

    2004-01-01

    By testing industry standard techniques for radon progeny evaluation on air sample filters, a new technique is developed to evaluate transuranic activity on air filters by curve fitting the decay curves. The industry method modified here is simply the use of filter activity measurements at different times to estimate the air concentrations of radon progeny. The primary modification was to not look for specific radon progeny values but rather transuranic activity. By using a method that will provide reasonably conservative estimates of the transuranic activity present on a filter, some credit for the decay curve shape can then be taken. By carrying out rigorous statistical analysis of the curve fits to over 65 samples having no transuranic activity taken over a 10-mo period, an optimization of the fitting function and quality tests for this purpose was attained.

  16. A new technique for preliminary estimates of TRU activity on air sample filters and radiological smears.

    PubMed

    Hayes, Robert

    2004-10-01

    In most nuclear facilities, fixed air samplers and sometimes portable air samplers are used where some probability of a release exists but is not expected, and so the added expense and effort of using a continuous air monitor is not deemed justified. When a release is suspected, naturally occurring radioactive material buildup on the filter typically prevents any quantitative measurements within the first day or so. Likewise, outdoor air measurements suffer from the same limitations (such as those taken during the Los Alamos fires) and so any rapid quantifiable measurements of fixed air sampler/portable air sampler filters which are technically defendable (even though conservative) are of use. The technique presented here is only intended for use in routine health physics survey applications and does not presently appear to be appropriate for sub pico Curie activity determinations. This study evaluates the utility of using a portable continuous air monitor as an alpha spectrometer to make transuranic activity determinations of samples using both the built in algorithm for air monitoring and a simple region of interest analysis. All samples evaluated were from air sample filters taken using a portable air sampler. Samples were taken over many months to quantify effects from natural variation in radon progeny activity distributions.

  17. Evaluation of membrane filter field monitors for microbiological air sampling

    NASA Technical Reports Server (NTRS)

    Fields, N. D.; Oxborrow, G. S.; Puleo, J. R.; Herring, C. M.

    1974-01-01

    Due to area constraints encountered in assembly and testing areas of spacecraft, the membrane filter field monitor (MF) and the National Aeronautics and Space Administration-accepted Reyniers slit air sampler were compared for recovery of airborne microbial contamination. The intramural air in a microbiological laboratory area and a clean room environment used for the assembly and testing of the Apollo spacecraft was studied. A significantly higher number of microorganisms was recovered by the Reyniers sampler. A high degree of consistency between the two sampling methods was shown by a regression analysis, with a correlation coefficient of 0.93. The MF samplers detected 79% of the concentration measured by the Reyniers slit samplers. The types of microorganisms identified from both sampling methods were similar.

  18. The NYC native air sampling pilot project: using HVAC filter data for urban biological incident characterization.

    PubMed

    Ackelsberg, Joel; Leykam, Frederic M; Hazi, Yair; Madsen, Larry C; West, Todd H; Faltesek, Anthony; Henderson, Gavin D; Henderson, Christopher L; Leighton, Terrance

    2011-09-01

    Native air sampling (NAS) is distinguished from dedicated air sampling (DAS) devices (eg, BioWatch) that are deployed to detect aerosol disseminations of biological threat agents. NAS uses filter samples from heating, ventilation, and air conditioning (HVAC) systems in commercial properties for environmental sampling after DAS detection of biological threat agent incidents. It represents an untapped, scientifically sound, efficient, widely distributed, and comparably inexpensive resource for postevent environmental sampling. Calculations predict that postevent NAS would be more efficient than environmental surface sampling by orders of magnitude. HVAC filter samples could be collected from pre-identified surrounding NAS facilities to corroborate the DAS alarm and delineate the path taken by the bioaerosol plume. The New York City (NYC) Native Air Sampling Pilot Project explored whether native air sampling would be acceptable to private sector stakeholders and could be implemented successfully in NYC. Building trade associations facilitated outreach to and discussions with property owners and managers, who expedited contact with building managers of candidate NAS properties that they managed or owned. Nominal NAS building requirements were determined; procedures to identify and evaluate candidate NAS facilities were developed; data collection tools and other resources were designed and used to expedite candidate NAS building selection and evaluation in Manhattan; and exemplar environmental sampling playbooks for emergency responders were completed. In this sample, modern buildings with single or few corporate tenants were the best NAS candidate facilities. The Pilot Project successfully demonstrated that in one urban setting a native air sampling strategy could be implemented with effective public-private collaboration.

  19. Crossett Hydrogen Sulfide Air Sampling Report

    EPA Pesticide Factsheets

    This report summarizes the results of the EPA’s hydrogen sulfide air monitoring conducted along Georgia Pacific’s wastewater treatment system and in surrounding Crossett, AR, neighborhoods in 2017.

  20. Applicability of canisters for sample storage in the determination of hazardous air pollutants

    NASA Astrophysics Data System (ADS)

    Kelly, Thomas J.; Holdren, Michael W.

    This paper evaluates the applicability of canisters for storage of air samples containing volatile organic compounds listed among the 189 hazardous air pollutants (HAPs) in the 1990 U.S. Clean Air Act Amendments. Nearly 100 HAPs have sufficient vapor pressure to be considered volatile compounds. Of those volatile organic HAPs, 52 have been tested previously for stability during storage in canisters. The published HAP stability studies are reviewed, illustrating that for most of the 52 HAPs tested, canisters are an effective sample storage approach. However, the published stability studies used a variety of canister types and test procedures, and generally considered only a few compounds in a very small set of canisters. A comparison of chemical and physical properties of the HAPs has also been conducted, to evaluate the applicability of canister sampling for other HAPs, for which canister stability testing has never been conducted. Of 45 volatile HAPs never tested in canisters, this comparison identifies nine for which canisters should be effective, and 17 for which canisters are not likely to be effective. For the other 19 HAPs, no clear decision can be reached on the likely applicability of air sample storage in canisters.

  1. Relationship of Indoor, Outdoor and Personal Air (RIOPA) study: study design, methods and quality assurance/control results.

    PubMed

    Weisel, Clifford P; Zhang, Junfeng; Turpin, Barbara J; Morandi, Maria T; Colome, Steven; Stock, Thomas H; Spektor, Dalia M; Korn, Leo; Winer, Arthur; Alimokhtari, Shahnaz; Kwon, Jaymin; Mohan, Krishnan; Harrington, Robert; Giovanetti, Robert; Cui, William; Afshar, Masoud; Maberti, Silvia; Shendell, Derek

    2005-03-01

    The Relationship of Indoor, Outdoor and Personal Air (RIOPA) Study was undertaken to evaluate the contribution of outdoor sources of air toxics, as defined in the 1990 Clean Air Act Amendments, to indoor concentrations and personal exposures. The concentrations of 18 volatile organic compounds (VOCs), 17 carbonyl compounds, and fine particulate matter mass (PM(2.5)) were measured using 48-h outdoor, indoor and personal air samples collected simultaneously. PM2.5 mass, as well as several component species (elemental carbon, organic carbon, polyaromatic hydrocarbons and elemental analysis) were also measured; only PM(2.5) mass is reported here. Questionnaires were administered to characterize homes, neighborhoods and personal activities that might affect exposures. The air exchange rate was also measured in each home. Homes in close proximity (<0.5 km) to sources of air toxics were preferentially (2:1) selected for sampling. Approximately 100 non-smoking households in each of Elizabeth, NJ, Houston, TX, and Los Angeles, CA were sampled (100, 105, and 105 respectively) with second visits performed at 84, 93, and 81 homes in each city, respectively. VOC samples were collected at all homes, carbonyls at 90% and PM(2.5) at 60% of the homes. Personal samples were collected from nonsmoking adults and a portion of children living in the target homes. This manuscript provides the RIOPA study design and quality control and assurance data. The results from the RIOPA study can potentially provide information on the influence of ambient sources on indoor air concentrations and exposure for many air toxics and will furnish an opportunity to evaluate exposure models for these compounds.

  2. ANITA Air Monitoring on the International Space Station: Results Compared to Other Measurements

    NASA Technical Reports Server (NTRS)

    Honne, A.; Schumann-Olsen, H.; Kaspersen, K.; Limero, T.; Macatangay, A.; Mosebach, H.; Kampf, D.; Mudgett, P. D.; James, J. T.; Tan, G.; hide

    2009-01-01

    ANITA (Analysing Interferometer for Ambient Air) is a flight experiment precursor for a permanent continuous air quality monitoring system on the ISS (International Space Station). For the safety of the crew, ANITA can detect and quantify quasi-online and simultaneously 33 gas compounds in the air with ppm or sub-ppm detection limits. The autonomous measurement system is based on FTIR (Fourier Transform Infra-Red spectroscopy). The system represents a versatile air quality monitor, allowing for the first time the detection and monitoring of trace gas dynamics in a spacecraft atmosphere. ANITA operated on the ISS from September 2007 to August 2008. This paper summarizes the results of ANITA s air analyses with emphasis on comparisons to other measurements. The main basis of comparison is NASA s set of grab samples taken onboard the ISS and analysed on ground applying various GC-based (Gas Chromatography) systems.

  3. Alpha Air Sample Counting Efficiency Versus Dust Loading: Evaluation of a Large Data Set

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hogue, M. G.; Gause-Lott, S. M.; Owensby, B. N.

    Dust loading on air sample filters is known to cause a loss of efficiency for direct counting of alpha activity on the filters, but the amount of dust loading and the correction factor needed to account for attenuated alpha particles is difficult to assess. In this paper, correction factors are developed by statistical analysis of a large database of air sample results for a uranium and plutonium processing facility at the Savannah River Site. As is typically the case, dust-loading data is not directly available, but sample volume is found to be a reasonable proxy measure; the amount of dustmore » loading is inferred by a combination of the derived correction factors and a Monte Carlo model. The technique compares the distribution of activity ratios [beta/(beta + alpha)] by volume and applies a range of correction factors on the raw alpha count rate. The best-fit results with this method are compared with MCNP modeling of activity uniformly deposited in the dust and analytical laboratory results of digested filters. Finally, a linear fit is proposed to evenly-deposited alpha activity collected on filters with dust loading over a range of about 2 mg cm -2 to 1,000 mg cm -2.« less

  4. Alpha Air Sample Counting Efficiency Versus Dust Loading: Evaluation of a Large Data Set

    DOE PAGES

    Hogue, M. G.; Gause-Lott, S. M.; Owensby, B. N.; ...

    2018-03-03

    Dust loading on air sample filters is known to cause a loss of efficiency for direct counting of alpha activity on the filters, but the amount of dust loading and the correction factor needed to account for attenuated alpha particles is difficult to assess. In this paper, correction factors are developed by statistical analysis of a large database of air sample results for a uranium and plutonium processing facility at the Savannah River Site. As is typically the case, dust-loading data is not directly available, but sample volume is found to be a reasonable proxy measure; the amount of dustmore » loading is inferred by a combination of the derived correction factors and a Monte Carlo model. The technique compares the distribution of activity ratios [beta/(beta + alpha)] by volume and applies a range of correction factors on the raw alpha count rate. The best-fit results with this method are compared with MCNP modeling of activity uniformly deposited in the dust and analytical laboratory results of digested filters. Finally, a linear fit is proposed to evenly-deposited alpha activity collected on filters with dust loading over a range of about 2 mg cm -2 to 1,000 mg cm -2.« less

  5. Use of alpha spectroscopy for conducting rapid surveys of transuranic activity on air sample filters and smears.

    PubMed

    Hayes, Robert B; Peña, Adan M; Goff, Thomas E

    2005-08-01

    This paper demonstrates the utility of a portable alpha Continuous Air Monitor (CAM) as a bench top scalar counter for multiple sample types. These include using the CAM to count fixed air sample filters and radiological smears. In counting radiological smears, the CAM is used very much like a gas flow proportional counter (GFPC), albeit with a lower efficiency. Due to the typically low background in this configuration, the minimum detectable activity for a 5-min count should be in the range of about 10 dpm which is acceptably below the 20 dpm limit for transuranic isotopes. When counting fixed air sample filters, the CAM algorithm along with other measurable characteristics can be used to identify and quantify the presence of transuranic isotopes in the samples. When the radiological control technician wants to take some credit from naturally occurring radioactive material contributions due to radon progeny producing higher energy peaks (as in the case with a fixed air sample filter), then more elaborate techniques are required. The techniques presented here will generate a decision level of about 43 dpm for such applications. The calibration for this application should alternatively be done using the default values of channels 92-126 for region of interest 1. This can be done within 10 to 15 min resulting in a method to rapidly evaluate air filters for transuranic activity. When compared to the 1-h count technique described by , the technique presented in the present work demonstrates a technique whereby more than two thirds of samples can be rapidly shown (within 10 to 15 min) to be within regulatory compliant limits. In both cases, however, spectral quality checks are required to insure sample self attenuation is not a significant bias in the activity estimates. This will allow the same level of confidence when using these techniques for activity quantification as is presently available for air monitoring activity quantification using CAMs.

  6. Permeability of gypsum samples dehydrated in air

    NASA Astrophysics Data System (ADS)

    Milsch, Harald; Priegnitz, Mike; Blöcher, Guido

    2011-09-01

    We report on changes in rock permeability induced by devolatilization reactions using gypsum as a reference analog material. Cylindrical samples of natural alabaster were dehydrated in air (dry) for up to 800 h at ambient pressure and temperatures between 378 and 423 K. Subsequently, the reaction kinetics, so induced changes in porosity, and the concurrent evolution of sample permeability were constrained. Weighing the heated samples in predefined time intervals yielded the reaction progress where the stoichiometric mass balance indicated an ultimate and complete dehydration to anhydrite regardless of temperature. Porosity showed to continuously increase with reaction progress from approximately 2% to 30%, whilst the initial bulk volume remained unchanged. Within these limits permeability significantly increased with porosity by almost three orders of magnitude from approximately 7 × 10-19 m2 to 3 × 10-16 m2. We show that - when mechanical and hydraulic feedbacks can be excluded - permeability, reaction progress, and porosity are related unequivocally.

  7. Determination of air-loop volume and radon partition coefficient for measuring radon in water sample.

    PubMed

    Lee, Kil Yong; Burnett, William C

    A simple method for the direct determination of the air-loop volume in a RAD7 system as well as the radon partition coefficient was developed allowing for an accurate measurement of the radon activity in any type of water. The air-loop volume may be measured directly using an external radon source and an empty bottle with a precisely measured volume. The partition coefficient and activity of radon in the water sample may then be determined via the RAD7 using the determined air-loop volume. Activity ratios instead of absolute activities were used to measure the air-loop volume and the radon partition coefficient. In order to verify this approach, we measured the radon partition coefficient in deionized water in the temperature range of 10-30 °C and compared the values to those calculated from the well-known Weigel equation. The results were within 5 % variance throughout the temperature range. We also applied the approach for measurement of the radon partition coefficient in synthetic saline water (0-75 ppt salinity) as well as tap water. The radon activity of the tap water sample was determined by this method as well as the standard RAD-H 2 O and BigBottle RAD-H 2 O. The results have shown good agreement between this method and the standard methods.

  8. Air sampling to assess potential generation of aerosolized viable bacteria during flow cytometric analysis of unfixed bacterial suspensions

    PubMed Central

    Carson, Christine F; Inglis, Timothy JJ

    2018-01-01

    This study investigated aerosolized viable bacteria in a university research laboratory during operation of an acoustic-assisted flow cytometer for antimicrobial susceptibility testing by sampling room air before, during and after flow cytometer use. The aim was to assess the risk associated with use of an acoustic-assisted flow cytometer analyzing unfixed bacterial suspensions. Air sampling in a nearby clinical laboratory was conducted during the same period to provide context for the existing background of microorganisms that would be detected in the air. The three species of bacteria undergoing analysis by flow cytometer in the research laboratory were Klebsiella pneumoniae, Burkholderia thailandensis and Streptococcus pneumoniae. None of these was detected from multiple 1000 L air samples acquired in the research laboratory environment. The main cultured bacteria in both locations were skin commensal and environmental bacteria, presumed to have been disturbed or dispersed in laboratory air by personnel movements during routine laboratory activities. The concentrations of bacteria detected in research laboratory air samples were reduced after interventional cleaning measures were introduced and were lower than those in the diagnostic clinical microbiology laboratory. We conclude that our flow cytometric analyses of unfixed suspensions of K. pneumoniae, B. thailandensis and S. pneumoniae do not pose a risk to cytometer operators or other personnel in the laboratory but caution against extrapolation of our results to other bacteria and/or different flow cytometric experimental procedures. PMID:29608197

  9. Optimization of sampling parameters for collection and preconcentration of alveolar air by needle traps.

    PubMed

    Filipiak, Wojciech; Filipiak, Anna; Ager, Clemens; Wiesenhofer, Helmut; Amann, Anton

    2012-06-01

    The approach for breath-VOCs' collection and preconcentration by applying needle traps was developed and optimized. The alveolar air was collected from only a few exhalations under visual control of expired CO(2) into a large gas-tight glass syringe and then warmed up to 45 °C for a short time to avoid condensation. Subsequently, a specially constructed sampling device equipped with Bronkhorst® electronic flow controllers was used for automated adsorption. This sampling device allows time-saving collection of expired/inspired air in parallel onto three different needle traps as well as improvement of sensitivity and reproducibility of NT-GC-MS analysis by collection of relatively large (up to 150 ml) volume of exhaled breath. It was shown that the collection of alveolar air derived from only a few exhalations into a large syringe followed by automated adsorption on needle traps yields better results than manual sorption by up/down cycles with a 1 ml syringe, mostly due to avoided condensation and electronically controlled stable sample flow rate. The optimal profile and composition of needle traps consists of 2 cm Carbopack X and 1 cm Carboxen 1000, allowing highly efficient VOCs' enrichment, while injection by a fast expansive flow technique requires no modifications in instrumentation and fully automated GC-MS analysis can be performed with a commercially available autosampler. This optimized analytical procedure considerably facilitates the collection and enrichment of alveolar air, and is therefore suitable for application at the bedside of critically ill patients in an intensive care unit. Due to its simplicity it can replace the time-consuming sampling of sufficient breath volume by numerous up/down cycles with a 1 ml syringe.

  10. Evaluation of solid sorbents for the determination of fenhexamid, metalaxyl-M, pyrimethanil, malathion and myclobutanil residues in air samples: application to monitoring malathion and fenhexamid dissipation in greenhouse air using C-18 or Supelpak-2 for sampling.

    PubMed

    Tsiropoulos, Nikolaos G; Bakeas, Evangelos B; Raptis, Vasilios; Batistatou, Stavroula S

    2006-07-28

    A methodology is described for greenhouse air analysis by sampling fenhexamid, pyrimethanil, malathion, metalaxyl-M and myclobutanil in solid sorbents. Pesticides were determined by gas chromatography with NP Detector. The trapping efficiency of XAD-2, XAD-4, Supelpak-2, Florisil and C-18 at different sampling conditions (rate, time and air humidity) and pesticides concentration levels has been evaluated. No breakthrough was observed in the range of concentration studied (0.10-75 microg of each pesticide). In almost all the cases good stability results were obtained. Personal pumps have been used with selected sorbents (Supelpak-2 and C-18) in order to sample malathion and fenhexamid in air of experimental greenhouse after their application in a tomato crop. The dissipation process of the analytes in various time periods after application has been studied. Malathion concentrations varied between 20.1 microg m(-3) just after application and 1.06 microg m(-3) 3 days later. Fenhexamid concentrations, determined by high performance liquid chromatography with UV detection, fall rapidly; after 12 h post-application being below 0.50 microg m(-3).

  11. First results from the oil sands passive air monitoring network for polycyclic aromatic compounds.

    PubMed

    Schuster, Jasmin K; Harner, Tom; Su, Ky; Mihele, Cristian; Eng, Anita

    2015-03-03

    Results are reported from an ongoing passive air monitoring study for polycyclic aromatic compounds (PACs) in the Athabasca oil sands region in Alberta, Canada. Polyurethane foam (PUF) disk passive air samplers were deployed for consecutive 2-month periods from November 2010 to June 2012 at 17 sites. Samples were analyzed for polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs, dibenzothiophene and its alkylated derivatives (DBTs). Relative to parent PAHs, alkylated PAHs and DBTs are enriched in bitumen and therefore considered to be petrogenic markers. Concentrations in air were in the range 0.03-210 ng/m(3), 0.15-230 ng/m(3) and 0.01-61 ng/m(3) for ∑PAHs, ∑alkylated PAHs and ΣDBTs, respectively. An exponential decline of the PAC concentrations in air with distance from mining areas and related petrogenic sources was observed. The most significant exponential declines were for the alkylated PAHs and DBTs and attributed to their association with mining-related emissions and near-source deposition, due to their lower volatility and greater association with depositing particles. Seasonal trends in concentrations in air for PACs were not observed for any of the compound classes. However, a forest fire episode during April to July 2011 resulted in greatly elevated PAH levels at all passive sampling locations. Alkylated PAHs and DBTs were not elevated during the forest fire period, supporting their association with petrogenic sources. Based on the results of this study, an "Athabasca PAC profile" is proposed as a potential source marker for the oil sands region. The profile is characterized by ∑PAHs/∑Alkylated PAHs = ∼0.2 and ∑PAHs/∑DBTs = ∼5.

  12. An Autosampler and Field Sample Carrier for Maximizing Throughput Using an Open-Air, Surface Sampling Ion Source for MS

    EPA Science Inventory

    A recently developed, commercially available, open-air, surface sampling ion source for mass spectrometers provides individual analyses in several seconds. To realize its full throughput potential, an autosampler and field sample carrier were designed and built. The autosampler ...

  13. A Comparison Study of Sampling and Analyzing Volatile Organic Compounds in Air in Kuwait by Using Tedlar Bags/Canisters and GC-MS with a Cryogenic Trap

    PubMed Central

    Tang, Hongmao; Beg, Khaliq R.; Al-Otaiba, Yousef

    2006-01-01

    Kuwait experiences desert climatic weather. Due to the extreme hot and dry conditions in this country, some analytical phenomena have been discovered. Therefore, a systematic study of sampling and analyzing volatile organic compounds in air by using GC-MS with a cryogenic trap is reported in this paper. This study included comparisons of using different sample containers such as Tedlar bags and SUMMA canisters, and different cryogenic freezing-out air volumes in the trap. Calibration curves for different compounds and improvement of replicated analysis results were also reported here. The study found that using different sample containers produced different results. Analysis of ambient air samples collected in Tedlar bags obtained several volatile organic compounds with large concentrations compared to using SUMMA canisters. Therefore, to choose a sample container properly is a key element for successfully completing a project. Because GC-MS with a cryogenic trap often generates replicated results with poor agreement, an internal standard added to gas standards and air samples by using a gas syringe was tested. The study results proved that it helped to improve the replicated results. PMID:16699723

  14. A comparison study of sampling and analyzing volatile organic compounds in air in Kuwait by using Tedlar bags/canisters and GC-MS with a cryogenic trap.

    PubMed

    Tang, Hongmao; Beg, Khaliq R; Al-Otaiba, Yousef

    2006-05-12

    Kuwait experiences desert climatic weather. Due to the extreme hot and dry conditions in this country, some analytical phenomena have been discovered. Therefore, a systematic study of sampling and analyzing volatile organic compounds in air by using GC-MS with a cryogenic trap is reported in this paper. This study included comparisons of using different sample containers such as Tedlar bags and SUMMA canisters, and different cryogenic freezing-out air volumes in the trap. Calibration curves for different compounds and improvement of replicated analysis results were also reported here. The study found that using different sample containers produced different results. Analysis of ambient air samples collected in Tedlar bags obtained several volatile organic compounds with large concentrations compared to using SUMMA canisters. Therefore, to choose a sample container properly is a key element for successfully completing a project. Because GC-MS with a cryogenic trap often generates replicated results with poor agreement, an internal standard added to gas standards and air samples by using a gas syringe was tested. The study results proved that it helped to improve the replicated results.

  15. Comparison of mold concentrations quantified by MSQPCR in indoor and outdoor air sampled simultaneously

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meklin, Teija; Reponen, Tina; McKinstry, Craig A.

    Mold specific quantitative PCR (MSQPCR) was used to measure the concentrations of 36 mold species in dust and in indoor and in outdoor air samples that were taken simultaneously in 17 homes in Cincinnati with no-known water damage. The total spore concentrations in the indoor (I) and outdoor (O) air samples were statistically significantly different and the concentrations in the three sample types of many of the individual species were significantly different (p < 0.05 based on the Wilcoxon Signed Rank Test). The I/O ratios of the averages or geometric means of the individual species were generally less than 1;more » but these I/O ratios were quite variable ranging from 0.03 for A. sydowii to 1.2 for Acremonium strictum. There were no significant correlations for the 36 specific mold concentrations between the dust samples and the indoor or outdoor air samples (based on the Spearman’s Rho test). The indoor and outdoor air concentrations of 32 of the species were not correlated. Only Aspergillus penicillioides, C. cladosporioides types 1 and 2 and C. herbarum had sufficient data to estimate a correlation at rho > 0.5 with signicance (p < 0.05) In six of these homes, a previous dust sample had been collected and analyzed 2 years earlier. The ERMI© values for the dust samples taken in the same home two years apart were not significantly different (p=0.22) based on Wilcoxon Signed Rank Test.« less

  16. Sampling and Analyzing Air Pollution: An Apparatus Suitable for Use in Schools.

    ERIC Educational Resources Information Center

    Rockwell, Dean M.; Hansen, Tony

    1994-01-01

    Describes two variations of an air sampler and analyzer that are inexpensive to construct, easy to operate, and designed to be used in an educational program. Variations use vacuum cleaners and aquarium pumps, and white facial tissues serve as filters. Samples of air pollution obtained by this method may be used from early grade school to advanced…

  17. Active AirCore Sampling: Constraining Point Sources of Methane and Other Gases with Fixed Wing Unmanned Aerial Systems

    NASA Astrophysics Data System (ADS)

    Bent, J. D.; Sweeney, C.; Tans, P. P.; Newberger, T.; Higgs, J. A.; Wolter, S.

    2017-12-01

    Accurate estimates of point source gas emissions are essential for reconciling top-down and bottom-up greenhouse gas measurements, but sampling such sources is challenging. Remote sensing methods are limited by resolution and cloud cover; aircraft methods are limited by air traffic control clearances, and the need to properly determine boundary layer height. A new sampling approach leverages the ability of unmanned aerial systems (UAS) to measure all the way to the surface near the source of emissions, improving sample resolution, and reducing the need to characterize a wide downstream swath, or measure to the full height of the planetary boundary layer (PBL). The "Active-AirCore" sampler, currently under development, will fly on a fixed wing UAS in Class G airspace, spiraling from the surface to 1200 ft AGL around point sources such as leaking oil wells to measure methane, carbon dioxide and carbon monoxide. The sampler collects a 100-meter long sample "core" of air in an 1/8" passivated stainless steel tube. This "core" is run on a high-precision instrument shortly after the UAS is recovered. Sample values are mapped to a specific geographic location by cross-referencing GPS and flow/pressure metadata, and fluxes are quantified by applying Gauss's theorem to the data, mapped onto the spatial "cylinder" circumscribed by the UAS. The AirCore-Active builds off the sampling ability and analytical approach of the related AirCore sampler, which profiles the atmosphere passively using a balloon launch platform, but will add an active pumping capability needed for near-surface horizontal sampling applications. Here, we show design elements, laboratory and field test results for methane, describe the overall goals of the mission, and discuss how the platform can be adapted, with minimal effort, to measure other gas species.

  18. EVALUATION OF THE FILTER PACK FOR LONG-DURATION SAMPLING OF AMBIENT AIR

    EPA Science Inventory

    A 14-week filter pack (FP) sampler evaluation field study was conducted at a site near Bondville, IL to investigate the impact of weekly sampling duration. Simultaneous samples were collected using collocated filter packs (FP) from two independent air quality monitoring networks...

  19. Sampling, storage, and analysis of C2-C7 non-methane hydrocarbons from the US National Oceanic and Atmospheric Administration Cooperative Air Sampling Network glass flasks.

    PubMed

    Pollmann, Jan; Helmig, Detlev; Hueber, Jacques; Plass-Dülmer, Christian; Tans, Pieter

    2008-04-25

    An analytical technique was developed to analyze light non-methane hydrocarbons (NMHC), including ethane, propane, iso-butane, n-butane, iso-pentane, n-pentane, n-hexane, isoprene, benzene and toluene from whole air samples collected in 2.5l-glass flasks used by the National Oceanic and Atmospheric Administration, Earth System Research Laboratory, Global Monitoring Division (NOAA ESRL GMD, Boulder, CO, USA) Cooperative Air Sampling Network. This method relies on utilizing the remaining air in these flasks (which is at below-ambient pressure at this stage) after the completion of all routine greenhouse gas measurements from these samples. NMHC in sample aliquots extracted from the flasks were preconcentrated with a custom-made, cryogen-free inlet system and analyzed by gas chromatography (GC) with flame ionization detection (FID). C2-C7 NMHC, depending on their ambient air mixing ratios, could be measured with accuracy and repeatability errors of generally < or =10-20%. Larger deviations were found for ethene and propene. Hexane was systematically overestimated due to a chromatographic co-elution problem. Saturated NMHC showed less than 5% changes in their mixing ratios in glass flask samples that were stored for up to 1 year. In the same experiment ethene and propene increased at approximately 30% yr(-1). A series of blank experiments showed negligible contamination from the sampling process and from storage (<10 pptv yr(-1)) of samples in these glass flasks. Results from flask NMHC analyses were compared to in-situ NMHC measurements at the Global Atmospheric Watch station in Hohenpeissenberg, Germany. This 9-months side-by-side comparison showed good agreement between both methods. More than 94% of all data comparisons for C2-C5 alkanes, isoprene, benzene and toluene fell within the combined accuracy and precision objectives of the World Meteorological Organization Global Atmosphere Watch (WMO-GAW) for NMHC measurements.

  20. Role of air sampling in investigation of an outbreak of legionnaires' disease associated with exposure to aerosols from an evaporative condenser.

    PubMed

    Breiman, R F; Cozen, W; Fields, B S; Mastro, T D; Carr, S J; Spika, J S; Mascola, L

    1990-06-01

    Epidemiologic studies have suggested that legionnaires' disease can be transmitted to susceptible hosts by contaminated aerosolized water from cooling towers and evaporative condensers; however, epidemic strains of Legionella have not been isolated by air sampling at such sites during epidemiologic investigations. An outbreak of legionnaires' disease occurred at a retirement hotel; Legionella pneumophila serogroup 1 was isolated from an evaporative condenser and from potable water. A case-control study showed that the only significant exposure risk was in area A. L. pneumophila serogroup 1 was isolated during air sampling near the evaporative condenser exhaust site, the air conditioning intake vent, and an air vent in area A, but not in shower stalls. Monoclonal antibody subtype patterns of L. pneumophila serogroup 1 isolates from patients matched those from the evaporative condenser but not from shower water. Air sampling and monoclonal antibody subtyping results support epidemiologic evidence that the evaporative condenser was the source of this outbreak.

  1. Air Sampling Data for BP Spill/Deepwater Horizon

    EPA Pesticide Factsheets

    The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following the explosion and sinking of the Deepwater Horizon oil rig, a sea-floor oil gusher flowed for 87 days, until it was capped on 15 July 2010.In response to the BP oil spill, EPA sampled air, water, sediment, and waste generated by the cleanup operations.

  2. Trace gas measurements from whole air samples collected over the Antarctic continent

    NASA Technical Reports Server (NTRS)

    Heidt, L. E.; Vedder, J. F.; Pollock, Walter H.; Henry, Bruce E.; Lueb, Richard A.

    1988-01-01

    Whole air samples collected aboard the NASA DC-8 and ER-2 aircraft as part of the Airborne Antarctic Ozone Experiment (AAOE) were analyzed in a field laboratory set up at Punta Arenas, Chile, in August and September, 1987. Mixing ratios obtained from gas chromatographic analyses of these samples are presented for N2O, CFCl3, CFCl2, C2F3Cl3, CH3CCl3, CH4, and CO. Variations in the mixing ratios of these gases along the individual flight paths of the aircraft are used as tracers to indicate the history of air masses over and near the Antarctic continent.

  3. Data Quality Objectives for Regulatory Requirements for Hazardous and Radioactive Air Emissions Sampling and Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    MULKEY, C.H.

    1999-07-06

    This document describes the results of the data quality objective (DQO) process undertaken to define data needs for state and federal requirements associated with toxic, hazardous, and/or radiological air emissions under the jurisdiction of the River Protection Project (RPP). Hereafter, this document is referred to as the Air DQO. The primary drivers for characterization under this DQO are the regulatory requirements pursuant to Washington State regulations, that may require sampling and analysis. The federal regulations concerning air emissions are incorporated into the Washington State regulations. Data needs exist for nonradioactive and radioactive waste constituents and characteristics as identified through themore » DQO process described in this document. The purpose is to identify current data needs for complying with regulatory drivers for the measurement of air emissions from RPP facilities in support of air permitting. These drivers include best management practices; similar analyses may have more than one regulatory driver. This document should not be used for determining overall compliance with regulations because the regulations are in constant change, and this document may not reflect the latest regulatory requirements. Regulatory requirements are also expected to change as various permits are issued. Data needs require samples for both radionuclides and nonradionuclide analytes of air emissions from tanks and stored waste containers. The collection of data is to support environmental permitting and compliance, not for health and safety issues. This document does not address health or safety regulations or requirements (those of the Occupational Safety and Health Administration or the National Institute of Occupational Safety and Health) or continuous emission monitoring systems. This DQO is applicable to all equipment, facilities, and operations under the jurisdiction of RPP that emit or have the potential to emit regulated air pollutants.« less

  4. Comparison of Grab, Air, and Surface Results for Radiation Site Characterization

    NASA Astrophysics Data System (ADS)

    Glassford, Eric Keith

    2011-12-01

    energy photons from 234Th and 234mPa, the short-lived decay products of 238U, and 235U. Two sided t-tests and coefficient of variation were used to compare sampling types. The large grab samples had the lowest calculated coefficient of variation results for activity and atom percentage. The wipe samples had the highest calculated coefficient of variation of mean specific activity (dis/sec/g) for all three energies. The air filter samples had the highest coefficient of variation calculation for mean atom percentage, for both uranium isotopes examined. The data indicated that the large mass sample was the most effective at characterizing the rolling mill radioactive site conditions, since this would indicate which samples had the smallest variations compared to the mean. Additionally, measurement results of natural uranium in the samples indicate that the distribution of radioactive contamination at the sampling location is most likely non-homogeneous and that the size of the sample collected and analyzed must be sufficiently large to insure that the analytical results are truly representative of the activity present.

  5. Inter-laboratory comparison study on measuring semi-volatile organic chemicals in standards and air samples.

    PubMed

    Su, Yushan; Hung, Hayley

    2010-11-01

    Measurements of semi-volatile organic chemicals (SVOCs) were compared among 21 laboratories from 7 countries through the analysis of standards, a blind sample, an air extract, and an atmospheric dust sample. Measurement accuracy strongly depended on analytes, laboratories, and types of standards and samples. Intra-laboratory precision was generally good with relative standard deviations (RSDs) of triplicate injections <10% and with median differences of duplicate samples between 2.1 and 22%. Inter-laboratory variability, measured by RSDs of all measurements, was in the range of 2.8-58% in analyzing standards, and 6.9-190% in analyzing blind sample and air extract. Inter-laboratory precision was poorer when samples were subject to cleanup processes, or when SVOCs were quantified at low concentrations. In general, inter-laboratory differences up to a factor of 2 can be expected to analyze atmospheric SVOCs. When comparing air measurements from different laboratories, caution should be exercised if the data variability is less than the inter-laboratory differences. 2010. Published by Elsevier Ltd. All rights reserved.

  6. Detection of Legionella spp. by a nested-PCR assay in air samples of a wastewater treatment plant and downwind distances in Isfahan

    PubMed Central

    Mirzaee, Seyyed Abbas; Nikaeen, Mahnaz; Hajizadeh, Yaghob; Nabavi, BiBi Fatemeh; Hassanzadeh, Akbar

    2015-01-01

    Background: Wastewater contains a variety of pathogens and bio -aerosols generated during the wastewater treatment process, which could be a potential health risk for exposed individuals. This study was carried out to detect Legionella spp. in the bio -aerosols generated from different processes of a wastewater treatment plant (WWTP) in Isfahan, Iran, and the downwind distances. Materials and Methods: A total of 54 air samples were collected and analyzed for the presence of Legionella spp. by a nested- polymerase chain reaction (PCR) assay. A liquid impingement biosampler was used to capture bio -aerosols. The weather conditions were also recorded. Results: Legionella were detected in 6% of the samples, including air samples above the aeration tank (1/9), belt filter press (1/9), and 250 m downwind (1/9). Conclusion: The result of this study revealed the presence of Legionella spp. in air samples of a WWTP and downwind distance, which consequently represent a potential health risk to the exposed individuals. PMID:25802817

  7. 2018 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffith, Stacy R.

    The 2018 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base has been prepared in accordance with the “Letter of Agreement Between Department of Energy, National Nuclear Security Administration, Sandia Field Office (DOE/NNSA/SFO) and 377th Air Base Wing (ABW), Kirtland Air Force Base (KAFB) for Terrestrial Sampling” (signed January 2017), Sandia National Laboratories, New Mexico (SNL/NM). The Letter of Agreement requires submittal of an annual terrestrial sampling plan.

  8. 2017 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffith, Stacy R.

    The 2017 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base has been prepared in accordance with the “Letter of Agreement Between Department of Energy, National Nuclear Security Administration, Sandia Field Office (DOE/NNSA/SFO) and 377th Air Base Wing (ABW), Kirtland Air Force Base (KAFB) for Terrestrial Sampling” (signed January 2017), Sandia National Laboratories, New Mexico (SNL/NM). The Letter of Agreement requires submittal of an annual terrestrial sampling plan.

  9. A sensitive LC-MS/MS method for measurement of organophosphorus pesticides and their oxygen analogs in air sampling matrices.

    PubMed

    Armstrong, Jenna L; Dills, Russell L; Yu, Jianbo; Yost, Michael G; Fenske, Richard A

    2014-01-01

    A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of levels of the organophosphorus (OP) pesticides chlorpyrifos (CPF), azinphos methyl (AZM), and their oxygen analogs chlorpyrifos-oxon (CPF-O) and azinphos methyl-oxon (AZM-O) on common active air sampling matrices. XAD-2 resin and polyurethane foam (PUF) matrices were extracted with acetonitrile containing stable-isotope labeled internal standards (ISTD). Analysis was accomplished in Multiple Reaction Monitoring (MRM) mode, and analytes in unknown samples were identified by retention time (±0.1 min) and qualifier ratio (±30% absolute) as compared to the mean of calibrants. For all compounds, calibration linearity correlation coefficients were ≥0.996. Limits of detection (LOD) ranged from 0.15-1.1 ng/sample for CPF, CPF-O, AZM, and AZM-O on active sampling matrices. Spiked fortification recoveries were 78-113% from XAD-2 active air sampling tubes and 71-108% from PUF active air sampling tubes. Storage stability tests also yielded recoveries ranging from 74-94% after time periods ranging from 2-10 months. The results demonstrate that LC-MS/MS is a sensitive method for determining these compounds from two different matrices at the low concentrations that can result from spray drift and long range transport in non-target areas following agricultural applications. In an inter-laboratory comparison, the limit of quantification (LOQ) for LC-MS/MS was 100 times lower than a typical gas chromatography-mass spectrometry (GC-MS) method.

  10. Glyphosate–rich air samples induce IL–33, TSLP and generate IL–13 dependent airway inflammation

    PubMed Central

    Kumar, Sudhir; Khodoun, Marat; Kettleson, Eric M.; McKnight, Christopher; Reponen, Tiina; Grinshpun, Sergey A.; Adhikari, Atin

    2014-01-01

    Several low weight molecules have often been implicated in the induction of occupational asthma. Glyphosate, a small molecule herbicide, is widely used in the world. There is a controversy regarding a role of glyphosate in developing asthma and rhinitis among farmers, the mechanism of which is unexplored. The aim of this study was to explore the mechanisms of glyphosate induced pulmonary pathology by utilizing murine models and real environmental samples. C57BL/6, TLR4−/−, and IL-13−/− mice inhaled extracts of glyphosate-rich air samples collected on farms during spraying of herbicides or inhaled different doses of glyphosate and ovalbumin. The cellular response, humoral response, and lung function of exposed mice were evaluated. Exposure to glyphosate-rich air samples as well as glyphosate alone to the lungs increased: eosinophil and neutrophil counts, mast cell degranulation, and production of IL-33, TSLP, IL-13, and IL-5. In contrast, in vivo systemic IL-4 production was not increased. Co-administration of ovalbumin with glyphosate did not substantially change the inflammatory immune response. However, IL-13-deficiency resulted in diminished inflammatory response but did not have a significant effect on airway resistance upon methacholine challenge after 7 or 21 days of glyphosate exposure. Glyphosate-rich farm air samples as well as glyphosate alone were found to induce pulmonary IL-13-dependent inflammation and promote Th2 type cytokines, but not IL-4 for glyphosate alone. This study, for the first time, provides evidence for the mechanism of glyphosate-induced occupational lung disease. PMID:25172162

  11. Effect of Sampling Depth on Air-Sea CO2 Flux Estimates in River-Stratified Arctic Coastal Waters

    NASA Astrophysics Data System (ADS)

    Miller, L. A.; Papakyriakou, T. N.

    2015-12-01

    In summer-time Arctic coastal waters that are strongly influenced by river run-off, extreme stratification severely limits wind mixing, making it difficult to effectively sample the surface 'mixed layer', which can be as shallow as 1 m, from a ship. During two expeditions in southwestern Hudson Bay, off the Nelson, Hayes, and Churchill River estuaries, we confirmed that sampling depth has a strong impact on estimates of 'surface' pCO2 and calculated air-sea CO2 fluxes. We determined pCO2 in samples collected from 5 m, using a typical underway system on the ship's seawater supply; from the 'surface' rosette bottle, which was generally between 1 and 3 m; and using a niskin bottle deployed at 1 m and just below the surface from a small boat away from the ship. Our samples confirmed that the error in pCO2 derived from typical ship-board versus small-boat sampling at a single station could be nearly 90 μatm, leading to errors in the calculated air-sea CO2 flux of more than 0.1 mmol/(m2s). Attempting to extrapolate such fluxes over the 6,000,000 km2 area of the Arctic shelves would generate an error approaching a gigamol CO2/s. Averaging the station data over a cruise still resulted in an error of nearly 50% in the total flux estimate. Our results have implications not only for the design and execution of expedition-based sampling, but also for placement of in-situ sensors. Particularly in polar waters, sensors are usually deployed on moorings, well below the surface, to avoid damage and destruction from drifting ice. However, to obtain accurate information on air-sea fluxes in these areas, it is necessary to deploy sensors on ice-capable buoys that can position the sensors in true 'surface' waters.

  12. Interpreting contact angle results under air, water and oil for the same surfaces

    NASA Astrophysics Data System (ADS)

    Ozkan, Orkun; Yildirim Erbil, H.

    2017-06-01

    Under-water and under-oil superhydropobicity and superhydrophilicity have gained significant attention over the last few years. In this study, contact angles on five flat surfaces (polypropylene, poly(methyl methacrylate), polycarbonate, TEFLON-FEP and glass slide) were measured in water drop-in-air, air bubble-under-water, oil drop-in-air, air bubble-under-oil, oil drop-under-water and water drop-under-oil conditions. Heptane, octane, nonane, decane, dodecane, and hexadecane hydrocarbons were used as oils. Immiscible water/oil pairs were previously mutually saturated to provide thermodynamical equilibrium conditions and their surface and interfacial tensions were determined experimentally. These pairs were used in the two-liquid contact angle measurements. Surface free energies of the solid surfaces in air were determined independently by using the van Oss-Good method, using the contact angle results of pure water, ethylene glycol, formamide, methylene iodide and α-bromonaphalene. In addition, Zisman’s ‘critical surface tension’ values were also determined for comparison. In theory, the summation of contact angle results in a complementary case would give a total of 180° for ideal surfaces. However, it was determined that there are large deviations from this rule in practical cases and these deviations depend on surface free energies of solids. Three complementary cases of (water-in-air with air bubble-under-water); (oil-in-air with air bubble-under-oil); and (oil-under-water with water-under-oil) were investigated in particular to determine the deviations from ideality. A novel approach, named ‘complementary hysteresis’ [γ WA(cosθ 1  -  cosθ 2) and γ OW(cosθ 6  -  cosθ 5)] was developed where γ WA and γ OW represent the interfacial tensions of water/air and oil/water, and θ 1, θ 2, θ 5, and θ 6 were the contact angles of water/air, air bubble/water, oil/water and water/oil respectively. It was experimentally determined that

  13. Early Detection of Foot-And-Mouth Disease Virus from Infected Cattle Using A Dry Filter Air Sampling System.

    PubMed

    Pacheco, J M; Brito, B; Hartwig, E; Smoliga, G R; Perez, A; Arzt, J; Rodriguez, L L

    2017-04-01

    Foot-and-mouth disease (FMD) is a highly contagious livestock disease of high economic impact. Early detection of FMD virus (FMDV) is fundamental for rapid outbreak control. Air sampling collection has been demonstrated as a useful technique for detection of FMDV RNA in infected animals, related to the aerogenous nature of the virus. In the current study, air from rooms housing individual (n = 17) or two groups (n = 4) of cattle experimentally infected with FDMV A24 Cruzeiro of different virulence levels was sampled to assess the feasibility of applying air sampling as a non-invasive, screening tool to identify sources of FMDV infection. Detection of FMDV RNA in air was compared with first detection of clinical signs and FMDV RNA levels in serum and oral fluid. FMDV RNA was detected in room air samples 1-3 days prior (seven animals) or on the same day (four animals) as the appearance of clinical signs in 11 of 12 individually housed cattle. Only in one case clinical signs preceded detection in air samples by one day. Overall, viral RNA in oral fluid or serum preceded detection in air samples by 1-2 days. Six individually housed animals inoculated with attenuated strains did not show clinical signs, but virus was detected in air in one of these cases 3 days prior to first detection in oral fluid. In groups of four cattle housed together, air detection always preceded appearance of clinical signs by 1-2 days and coincided more often with viral shedding in oral fluid than virus in blood. These data confirm that air sampling is an effective non-invasive screening method for detecting FMDV infection in confined to enclosed spaces (e.g. auction barns, milking parlours). This technology could be a useful tool as part of a surveillance strategy during FMD prevention, control or eradication efforts. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  14. EPA's Response to the February 2014 Release of Radioactive Material from the Waste Isolation Pilot Plant (WIPP): EPA's WIPP Air Sampling Data from April 2014

    EPA Pesticide Factsheets

    In April 2014, U.S. Environmental Protection Agency (EPA) environmental monitoring and assessment team members reviewed DOE's air sampling plan, visited DOE's air samplers and placed air samplers onsite near existing DOE samplers to corroborate results.

  15. Bioassay vs. Air Sampling: Practical Guidance and Experience at Hanford

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Carlson, Eric W.; Hill, Robin L.

    2004-02-08

    The Hanford Site has implemented a policy to guide in determining whether air sampling data or special fecal bioassay data are more appropriate for determining doses of record for low-level plutonium exposures. The basis for the policy and four years of experience in comparing DAC-hours exposure with bioassay-based dosimetry is discussed.

  16. International system of units traceable results of Hg mass concentration at saturation in air from a newly developed measurement procedure.

    PubMed

    Quétel, Christophe R; Zampella, Mariavittoria; Brown, Richard J C; Ent, Hugo; Horvat, Milena; Paredes, Eduardo; Tunc, Murat

    2014-08-05

    Data most commonly used at present to calibrate measurements of mercury vapor concentrations in air come from a relationship known as the "Dumarey equation". It uses a fitting relationship to experimental results obtained nearly 30 years ago. The way these results relate to the international system of units (SI) is not known. This has caused difficulties for the specification and enforcement of limit values for mercury concentrations in air and in emissions to air as part of national or international legislation. Furthermore, there is a significant discrepancy (around 7% at room temperature) between the Dumarey data and data calculated from results of mercury vapor pressure measurements in the presence of only liquid mercury. As an attempt to solve some of these problems, a new measurement procedure is described for SI traceable results of gaseous Hg concentrations at saturation in milliliter samples of air. The aim was to propose a scheme as immune as possible to analytical biases. It was based on isotope dilution (ID) in the liquid phase with the (202)Hg enriched certified reference material ERM-AE640 and measurements of the mercury isotope ratios in ID blends, subsequent to a cold vapor generation step, by inductively coupled plasma mass spectrometry. The process developed involved a combination of interconnected valves and syringes operated by computer controlled pumps and ensured continuity under closed circuit conditions from the air sampling stage onward. Quantitative trapping of the gaseous mercury in the liquid phase was achieved with 11.5 μM KMnO4 in 2% HNO3. Mass concentrations at saturation found from five measurements under room temperature conditions were significantly higher (5.8% on average) than data calculated from the Dumarey equation, but in agreement (-1.2% lower on average) with data based on mercury vapor pressure measurement results. Relative expanded combined uncertainties were estimated following a model based approach. They ranged from 2

  17. Can Particulate Air Sampling Predict Microbial Load in Operating Theatres for Arthroplasty?

    PubMed Central

    Cristina, Maria Luisa; Spagnolo, Anna Maria; Sartini, Marina; Panatto, Donatella; Gasparini, Roberto; Orlando, Paolo; Ottria, Gianluca; Perdelli, Fernanda

    2012-01-01

    Several studies have proposed that the microbiological quality of the air in operating theatres be indirectly evaluated by means of particle counting, a technique derived from industrial clean-room technology standards, using airborne particle concentration as an index of microbial contamination. However, the relationship between particle counting and microbiological sampling has rarely been evaluated and demonstrated in operating theatres. The aim of the present study was to determine whether particle counting could predict microbiological contamination of the air in an operating theatre during 95 surgical arthroplasty procedures. This investigation was carried out over a period of three months in 2010 in an orthopedic operating theatre devoted exclusively to prosthetic surgery. During each procedure, the bacterial contamination of the air was determined by means of active sampling; at the same time, airborne particulate contamination was assessed throughout the entire procedure. On considering the total number of surgical operations, the mean value of the total bacterial load in the center of the operating theatre proved to be 35 CFU/m3; the mean particle count was 4,194,569 no./m3 for particles of diameter ≥0.5 µm and 13,519 no./m3 for particles of diameter ≥5 µm. No significant differences emerged between the median values of the airborne microbial load recorded during the two types of procedure monitored. Particulates with a diameter of ≥0.5 µm were detected in statistically higher concentrations (p<0.001) during knee-replacement procedures. By contrast, particulates with a diameter of ≥5 µm displayed a statistically higher concentration during hip-replacement procedures (p<0.05). The results did not reveal any statistically significant correlation between microbial loads and particle counts for either of the particle diameters considered (≥0.5 µm and ≥5 µm). Consequently, microbiological monitoring remains the most suitable method of

  18. Can particulate air sampling predict microbial load in operating theatres for arthroplasty?

    PubMed

    Cristina, Maria Luisa; Spagnolo, Anna Maria; Sartini, Marina; Panatto, Donatella; Gasparini, Roberto; Orlando, Paolo; Ottria, Gianluca; Perdelli, Fernanda

    2012-01-01

    Several studies have proposed that the microbiological quality of the air in operating theatres be indirectly evaluated by means of particle counting, a technique derived from industrial clean-room technology standards, using airborne particle concentration as an index of microbial contamination. However, the relationship between particle counting and microbiological sampling has rarely been evaluated and demonstrated in operating theatres. The aim of the present study was to determine whether particle counting could predict microbiological contamination of the air in an operating theatre during 95 surgical arthroplasty procedures. This investigation was carried out over a period of three months in 2010 in an orthopedic operating theatre devoted exclusively to prosthetic surgery. During each procedure, the bacterial contamination of the air was determined by means of active sampling; at the same time, airborne particulate contamination was assessed throughout the entire procedure. On considering the total number of surgical operations, the mean value of the total bacterial load in the center of the operating theatre proved to be 35 CFU/m(3); the mean particle count was 4,194,569 no./m(3) for particles of diameter ≥0.5 µm and 13,519 no./m(3) for particles of diameter ≥5 µm. No significant differences emerged between the median values of the airborne microbial load recorded during the two types of procedure monitored. Particulates with a diameter of ≥0.5 µm were detected in statistically higher concentrations (p<0.001) during knee-replacement procedures. By contrast, particulates with a diameter of ≥5 µm displayed a statistically higher concentration during hip-replacement procedures (p<0.05). The results did not reveal any statistically significant correlation between microbial loads and particle counts for either of the particle diameters considered (≥0.5 µm and ≥5 µm). Consequently, microbiological monitoring remains the most suitable method of

  19. Salmonella recovery following air chilling for matched neck-skin and whole carcass sampling methodologies

    USDA-ARS?s Scientific Manuscript database

    The prevalence and serogroups of Salmonella recovered following air chilling were determined for both enriched neck skin and matching enriched whole carcass samples. Commercially processed and eviscerated carcasses were air chilled to 4C before removing the neck skin (8.3 g) and stomaching in 83 mL...

  20. A sensitive LC-MS/MS method for measurement of organophosphorus pesticides and their oxygen analogs in air sampling matrices

    PubMed Central

    ARMSTRONG, JENNA L.; DILLS, RUSSELL L.; YU, JIANBO; YOST, MICHAEL G.; FENSKE, RICHARD A.

    2018-01-01

    A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of levels of the organophosphorus (OP) pesticides chlorpyrifos (CPF), azinphos methyl (AZM), and their oxygen analogs chlorpyrifos-oxon (CPF-O) and azinphos methyl-oxon (AZM-O) on common active air sampling matrices. XAD-2 resin and polyurethane foam (PUF) matrices were extracted with acetonitrile containing stable-isotope labeled internal standards (ISTD). Analysis was accomplished in Multiple Reaction Monitoring (MRM) mode, and analytes in unknown samples were identified by retention time (±0.1 min) and qualifier ratio (±30% absolute) as compared to the mean of calibrants. For all compounds, calibration linearity correlation coefficients were ≥0.996. Limits of detection (LOD) ranged from 0.15–1.1 ng/sample for CPF, CPF-O, AZM, and AZM-O on active sampling matrices. Spiked fortification recoveries were 78–113% from XAD-2 active air sampling tubes and 71–108% from PUF active air sampling tubes. Storage stability tests also yielded recoveries ranging from 74–94% after time periods ranging from 2–10 months. The results demonstrate that LC-MS/MS is a sensitive method for determining these compounds from two different matrices at the low concentrations that can result from spray drift and long range transport in non-target areas following agricultural applications. In an inter-laboratory comparison, the limit of quantification (LOQ) for LC-MS/MS was 100 times lower than a typical gas chromatography-mass spectrometry (GC-MS) method. PMID:24328542

  1. Whole Air Sampling During NASA's March-April 1999 Pacific Exploratory Expedition (PEM-Tropics B)

    NASA Technical Reports Server (NTRS)

    Blake, Donald R.

    2001-01-01

    University of California, Irvine (UCI) collected more than 4500 samples whole air samples collected over the remote Pacific Ocean during NASA's Global Tropospheric Experiment (GTE) Pacific Exploratory Mission-Tropics B (PEM-Tropics B) in March and early April 1999. Approximately 140 samples during a typical 8-hour DC-8 flight, and 120 canisters for each 8-hour flight aboard the P-3B. These samples were obtained roughly every 3-7 min during horizontal flight legs and 1-3 min during vertical legs. The filled canisters were analyzed in the laboratory at UCI within ten days of collection. The mixing ratios of 58 trace gases comprising hydrocarbons, halocarbons, alkyl nitrates and DMS were reported (and archived) for each sample. Two identical analytical systems sharing the same standards were operated simultaneously around the clock to improve canister turn-around time and to keep our measurement precision optimal. This report presents a summary of the results for sample collected.

  2. Water- and air-quality monitoring of the Sweetwater Reservoir Watershed, San Diego County, California - Phase One results, continued, 2001-2003

    USGS Publications Warehouse

    Mendez, Gregory O.; Foreman, William T.; Morita, Andrew; Majewski, Michael S.

    2008-01-01

    In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to monitor water, air, and sediment at the Sweetwater and Loveland Reservoirs in San Diego County, California. The study includes regular sampling of water and air at Sweetwater Reservoir for chemical constituents, including volatile organic compounds (VOC), polynuclear aromatic hydrocarbons (PAH), pesticides, and major and trace elements. The purpose of this study is to monitor changes in contaminant composition and concentration during the construction and operation of State Route 125. To accomplish this, the study was divided into two phases. Phase One sampling (water years 1998–2004) determined baseline conditions for the detection frequency and the concentrations of target compounds in air and water. Phase Two sampling (starting water year 2005) continues at selected monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment may have on water quality in the reservoir. Water samples were collected for VOCs and pesticides at Loveland Reservoir during Phase One and will be collected during Phase Two for comparison purposes. Air samples collected to monitor changes in VOCs, PAHs, and pesticides were analyzed by adapting methods used to analyze water samples. Bed-sediment samples have been and will be collected three times during the study; at the beginning of Phase One, at the start of Phase Two, and near the end of the study. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as trace metals, anthropogenic indicator compounds, and pharmaceuticals. This report describes the study design, and the sampling and analytical methods, and presents data from water and air samples collected during the fourth and fifth years of Phase One of the study (October 2001 to September 2003). Data collected during the first three

  3. Use of Whole-Genome Sequencing to Link Burkholderia pseudomallei from Air Sampling to Mediastinal Melioidosis, Australia

    PubMed Central

    Price, Erin P.; Mayo, Mark; Kaestli, Mirjam; Theobald, Vanessa; Harrington, Ian; Harrington, Glenda; Sarovich, Derek S.

    2015-01-01

    The frequency with which melioidosis results from inhalation rather than percutaneous inoculation or ingestion is unknown. We recovered Burkholderia pseudomallei from air samples at the residence of a patient with presumptive inhalational melioidosis and used whole-genome sequencing to link the environmental bacteria to B. pseudomallei recovered from the patient. PMID:26488732

  4. An Improved, Automated Whole-Air Sampler and VOC Analysis System: Results from SONGNEX 2015

    NASA Astrophysics Data System (ADS)

    Lerner, B. M.; Gilman, J.; Tokarek, T. W.; Peischl, J.; Koss, A.; Yuan, B.; Warneke, C.; Isaacman-VanWertz, G. A.; Sueper, D.; De Gouw, J. A.; Aikin, K. C.

    2015-12-01

    Accurate measurement of volatile organic compounds (VOCs) in the troposphere is critical for the understanding of emissions and physical and chemical processes that can impact both air quality and climate. Airborne VOC measurements have proven challenging due to the requirements of short sample collection times (=10 s) to maximize spatial resolution and sampling frequency and high sensitivity (pptv) to chemically diverse hydrocarbons, halocarbons, oxygen- and nitrogen-containing VOCs. NOAA ESRL CSD has built an improved whole air sampler (iWAS) which collects compressed ambient air samples in electropolished stainless steel canisters, based on the NCAR HAIS Advanced Whole Air Sampler [Atlas and Blake]. Post-flight chemical analysis is performed with a custom-built gas chromatograph-mass spectrometer system that pre-concentrates analyte cryostatically via a Stirling cooler, an electromechanical chiller which precludes the need for liquid nitrogen to reach trapping temperatures. For the 2015 Shale Oil and Natural Gas Nexus Study (SONGNEX), CSD conducted iWAS measurements on 19 flights aboard the NOAA WP-3D aircraft between March 19th and April 27th. Nine oil and natural gas production regions were surveyed during SONGNEX and more than 1500 air samples were collected and analyzed. For the first time, we employed real-time mapping of sample collection combined with live data from fast time-response measurements (e.g. ethane) for more uniform surveying and improved target plume sampling. Automated sample handling allowed for more than 90% of iWAS canisters to be analyzed within 96 hours of collection - for the second half of the campaign improved efficiencies reduced the median sample age at analysis to 36 hours. A new chromatography peak-fitting software package was developed to minimize data reduction time by an order of magnitude without a loss of precision or accuracy. Here we report mixing ratios for aliphatic and aromatic hydrocarbons (C2-C8) along with select

  5. The lung cancer breath signature: a comparative analysis of exhaled breath and air sampled from inside the lungs

    NASA Astrophysics Data System (ADS)

    Capuano, Rosamaria; Santonico, Marco; Pennazza, Giorgio; Ghezzi, Silvia; Martinelli, Eugenio; Roscioni, Claudio; Lucantoni, Gabriele; Galluccio, Giovanni; Paolesse, Roberto; di Natale, Corrado; D'Amico, Arnaldo

    2015-11-01

    Results collected in more than 20 years of studies suggest a relationship between the volatile organic compounds exhaled in breath and lung cancer. However, the origin of these compounds is still not completely elucidated. In spite of the simplistic vision that cancerous tissues in lungs directly emit the volatile metabolites into the airways, some papers point out that metabolites are collected by the blood and then exchanged at the air-blood interface in the lung. To shed light on this subject we performed an experiment collecting both the breath and the air inside both the lungs with a modified bronchoscopic probe. The samples were measured with a gas chromatography-mass spectrometer (GC-MS) and an electronic nose. We found that the diagnostic capability of the electronic nose does not depend on the presence of cancer in the sampled lung, reaching in both cases an above 90% correct classification rate between cancer and non-cancer samples. On the other hand, multivariate analysis of GC-MS achieved a correct classification rate between the two lungs of only 76%. GC-MS analysis of breath and air sampled from the lungs demonstrates a substantial preservation of the VOCs pattern from inside the lung to the exhaled breath.

  6. Ecotoxicological studies of environmental samples from Buenos Aires area using a standardized amphibian embryo toxicity test (AMPHITOX).

    PubMed

    Herkovits, Jorge; Perez-Coll, Cristina; Herkovits, Francisco D

    2002-01-01

    The toxicity of 34 environmental samples from potentially polluted and reference stations were evaluated by means of the AMPHITOX test from acute to chronic exposure according to the toxicity found in each sample. The samples were obtained from surface and ground water, leaches, industrial effluents and soils. The data, expressed in acute, short-term chronic and chronic Toxicity Units (TUa, TUstc and TUc) resulted in a maximal value of 1000 TUc, found in a leach, while the lower toxicity value was 1.4 TUa corresponding to two surface water samples. In five samples (four providing from reference places) no toxicity was detected. The results point out the possibility of evaluating the toxicity of a wide diversity of samples by means of AMPHITOX as a customized toxicity test. The fact that almost all samples with suspected toxicity in rivers and streams from the Metropolitan area of Buenos Aires city resulted toxic, indicates the need of enhanced stewardship of chemical substances for environmental and human health protection purposes.

  7. Determination of trichloroanisole and trichlorophenol in wineries' ambient air by passive sampling and thermal desorption-gas chromatography coupled to tandem mass spectrometry.

    PubMed

    Camino-Sánchez, F J; Bermúdez-Peinado, R; Zafra-Gómez, A; Ruíz-García, J; Vílchez-Quero, J L

    2015-02-06

    The present paper describes the calibration of selected passive samplers used in the quantitation of trichlorophenol and trichloroanisole in wineries' ambient air, by calculating the corresponding sampling rates. The method is based on passive sampling with sorbent tubes and involves thermal desorption-gas chromatography-triple quadrupole mass spectrometry analysis. Three commercially available sorbents were tested using sampling cartridges with a radial design instead of axial ones. The best results were found for Tenax TA™. Sampling rates (R-values) for the selected sorbents were determined. Passive sampling was also used for accurately determining the amount of compounds present in the air. Adequate correlation coefficients between the mass of the target analytes and exposure time were obtained. The proposed validated method is a useful tool for the early detection of trichloroanisole and its precursor trichlorophenol in wineries' ambient air while avoiding contamination of wine or winery facilities. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Cytotoxic and Inflammatory Potential of Air Samples from Occupational Settings with Exposure to Organic Dust

    PubMed Central

    Viegas, Susana; Caetano, Liliana Aranha; Korkalainen, Merja; Faria, Tiago; Pacífico, Cátia; Carolino, Elisabete; Quintal Gomes, Anita; Viegas, Carla

    2017-01-01

    Organic dust and related microbial exposures are the main inducers of several respiratory symptoms. Occupational exposure to organic dust is very common and has been reported in diverse settings. In vitro tests using relevant cell cultures can be very useful for characterizing the toxicity of complex mixtures present in the air of occupational environments such as organic dust. In this study, the cell viability and the inflammatory response, as measured by the production of pro-inflammatory cytokines tumor necrosis factor-α (TNFα) and interleukin-1 β (IL-1β), were determined in human macrophages derived from THP-1 monocytic cells. These cells were exposed to air samples from five occupational settings known to possess high levels of contamination of organic dust: poultry and swine feed industries, waste sorting, poultry production and slaughterhouses. Additionally, fungi and particle contamination of those settings was studied to better characterize the organic dust composition. All air samples collected from the assessed workplaces caused both cytotoxic and pro-inflammatory effects. The highest responses were observed in the feed industry, particularly in swine feed production. This study emphasizes the importance of measuring the organic dust/mixture effects in occupational settings and suggests that differences in the organic dust content may result in differences in health effects for exposed workers. PMID:29051440

  9. Breakthrough of 1,3-dichloropropene and chloropicrin from 600 mg XAD-4 air sampling tubes

    USDA-ARS?s Scientific Manuscript database

    Accurately measuring air concentrations of agricultural fumigants is important for the regulation of air quality. Understanding the conditions under which sorbent tubes can effectively retain such fumigants during sampling is critical in mitigating chemical breakthrough from the tubes and facilitati...

  10. Effects of indoor air purification by an air cleaning system (Koala technology) on semen parameters in male factor infertility: results of a pilot study.

    PubMed

    Paradisi, R; Vanella, S; Barzanti, R; Cani, C; Battaglia, C; Seracchioli, R; Venturoli, S

    2009-06-01

    A number of studies indicated a clear decline in semen quality in the past 30-50 years and there is accumulating evidence that this decline might result from exposure to high levels of air pollution. To examine the impact of environment on male reproductive ability, we undertook for the first time a pilot study on semen quality of infertile men exposed to purification of indoor air. Ten subjects with a history of unexplained male infertility and poor semen quality were exposed for at least 1 year to a cleaning indoor air system (Koala technology). The key feature of this air purifier is the unique innovative multiple filtering system. The treatment of total purification of indoor air showed neither improvements in semen parameters nor variation in reproductive hormones (P = N.S.), but induced an evident increase (P < 0.03 and more) in seminal leucocytic concentrations. Within the limits due to the small sample of subjects recruited, the sole purification of indoor air does not seem enough to improve semen quality, although the increase in leucocytic concentrations could indicate an activation of the role of immunosurveillance in a purified indoor air environment.

  11. Ozone measurement system for NASA global air sampling program

    NASA Technical Reports Server (NTRS)

    Tiefermann, M. W.

    1979-01-01

    The ozone measurement system used in the NASA Global Air Sampling Program is described. The system uses a commercially available ozone concentration monitor that was modified and repackaged so as to operate unattended in an aircraft environment. The modifications required for aircraft use are described along with the calibration techniques, the measurement of ozone loss in the sample lines, and the operating procedures that were developed for use in the program. Based on calibrations with JPL's 5-meter ultraviolet photometer, all previously published GASP ozone data are biased high by 9 percent. A system error analysis showed that the total system measurement random error is from 3 to 8 percent of reading (depending on the pump diaphragm material) or 3 ppbv, whichever are greater.

  12. Variables Related to Pre-Service Cannabis Use in a Sample of Air Force Enlistees.

    ERIC Educational Resources Information Center

    Mullins, Cecil J.; And Others

    This report is an attempt to add to the existing information about cannabis use, its correlates, and its effects. The sample population consisted of self-admitted abusers of various drugs, identified shortly after entering the Air Force. The subjects (N=4688) were located through the Drug Control Office at Lackland Air Force Base. Variables…

  13. Evaluation of sampling methods for measuring exposure to volatile inorganic acids in workplace air. Part 1: sampling hydrochloric acid (HCl) and nitric acid (HNO₃) from a test gas atmosphere.

    PubMed

    Howe, Alan; Musgrove, Darren; Breuer, Dietmar; Gusbeth, Krista; Moritz, Andreas; Demange, Martine; Oury, Véronique; Rousset, Davy; Dorotte, Michel

    2011-08-01

    Historically, workplace exposure to the volatile inorganic acids hydrochloric acid (HCl) and nitric acid (HNO(3)) has been determined mostly by collection on silica gel sorbent tubes and analysis of the corresponding anions by ion chromatography (IC). However, HCl and HNO(3) can be present in workplace air in the form of mist as well as vapor, so it is important to sample the inhalable fraction of airborne particles. As sorbent tubes exhibit a low sampling efficiency for inhalable particles, a more suitable method was required. This is the first of two articles on "Evaluation of Sampling Methods for Measuring Exposure to Volatile Inorganic Acids in Workplace Air" and describes collaborative sampling exercises carried out to evaluate an alternative method for sampling HCl and HNO(3) using sodium carbonate-impregnated filters. The second article describes sampling capacity and breakthrough tests. The method was found to perform well and a quartz fiber filter impregnated with 500 μL of 1 M Na(2)CO(3) (10% (m/v) Na(2)CO(3)) was found to have sufficient sampling capacity for use in workplace air measurement. A pre-filter is required to remove particulate chlorides and nitrates that when present would otherwise result in a positive interference. A GSP sampler fitted with a plastic cone, a closed face cassette, or a plastic IOM sampler were all found to be suitable for mounting the pre-filter and sampling filter(s), but care has to be taken with the IOM sampler to ensure that the sampler is tightly closed to avoid leaks. HCl and HNO(3) can react with co-sampled particulate matter on the pre-filter, e.g., zinc oxide, leading to low results, and stronger acids can react with particulate chlorides and nitrates removed by the pre-filter to liberate HCl and HNO(3), which are subsequently collected on the sampling filter, leading to high results. However, although there is this potential for both positive and negative interferences in the measurement, these are unavoidable

  14. Lagrangian Sampling of 3-D Air Quality Model Results for Regional Transport Contributions to Sulfate Aerosol Concentrations at Baltimore, MD in Summer of 2004

    EPA Science Inventory

    The Lagrangian method provides estimates of the chemical and physical evolution of air arriving in the daytime boundary layer at Baltimore. Study results indicate a dominant role for regional transport contributions of those days when sulfate air pollution is highest in Baltimor...

  15. AirCore-HR: a high-resolution column sampling to enhance the vertical description of CH4 and CO2

    NASA Astrophysics Data System (ADS)

    Membrive, Olivier; Crevoisier, Cyril; Sweeney, Colm; Danis, François; Hertzog, Albert; Engel, Andreas; Bönisch, Harald; Picon, Laurence

    2017-06-01

    An original and innovative sampling system called AirCore was presented by NOAA in 2010 Karion et al.(2010). It consists of a long ( > 100 m) and narrow ( < 1 cm) stainless steel tube that can retain a profile of atmospheric air. The captured air sample has then to be analyzed with a gas analyzer for trace mole fraction. In this study, we introduce a new AirCore aiming to improve resolution along the vertical with the objectives to (i) better capture the vertical distribution of CO2 and CH4, (ii) provide a tool to compare AirCores and validate the estimated vertical resolution achieved by AirCores. This (high-resolution) AirCore-HR consists of a 300 m tube, combining 200 m of 0.125 in. (3.175 mm) tube and a 100 m of 0.25 in. (6.35 mm) tube. This new configuration allows us to achieve a vertical resolution of 300 m up to 15 km and better than 500 m up to 22 km (if analysis of the retained sample is performed within 3 h). The AirCore-HR was flown for the first time during the annual StratoScience campaign from CNES in August 2014 from Timmins (Ontario, Canada). High-resolution vertical profiles of CO2 and CH4 up to 25 km were successfully retrieved. These profiles revealed well-defined transport structures in the troposphere (also seen in CAMS-ECMWF high-resolution forecasts of CO2 and CH4 profiles) and captured the decrease of CO2 and CH4 in the stratosphere. The multi-instrument gondola also carried two other low-resolution AirCore-GUF that allowed us to perform direct comparisons and study the underlying processing method used to convert the sample of air to greenhouse gases vertical profiles. In particular, degrading the AirCore-HR derived profiles to the low resolution of AirCore-GUF yields an excellent match between both sets of CH4 profiles and shows a good consistency in terms of vertical structures. This fully validates the theoretical vertical resolution achievable by AirCores. Concerning CO2 although a good agreement is found in terms of vertical structure

  16. Direct measurements of sample heating by a laser-induced air plasma in pre-ablation spark dual-pulse laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Register, Janna; Scaffidi, Jonathan; Angel, S Michael

    2012-08-01

    Direct measurements of temperature changes were made using small thermocouples (TC), placed near a laser-induced air plasma. Temperature changes up to ~500 °C were observed. From the measured temperature changes, estimates were made of the amount of heat absorbed per unit area. This allowed calculations to be made of the surface temperature, as a function of time, of a sample heated by the air plasma that is generated during orthogonal pre-ablation spark dual-pulse (DP) LIBS measurements. In separate experiments, single-pulse (SP) LIBS emission and sample ablation rate measurements were performed on nickel at sample temperatures ranging from room temperature to the maximum surface temperature that was calculated using the TC measurement results (500 °C). A small, but real sample temperature-dependent increase in both SP LIBS emission and the rate of sample ablation was found for nickel samples heated up to 500 °C. Comparison of DP LIBS emission enhancement values for bulk nickel samples at room temperature versus the enhanced SP LIBS emission and sample ablation rates observed as a function of increasing sample temperature suggests that sample heating by the laser-induced air plasma plays only a minor role in DP LIBS emission enhancement.

  17. Passive Samplers for Investigations of Air Quality: Method Description, Implementation, and Comparison to Alternative Sampling Methods

    EPA Science Inventory

    This Paper covers the basics of passive sampler design, compares passive samplers to conventional methods of air sampling, and discusses considerations when implementing a passive sampling program. The Paper also discusses field sampling and sample analysis considerations to ensu...

  18. TECHNOLOGY EVALUATION REPORT CEREX ENVIRONMENTAL SERVICES UV HOUND POINT SAMPLE AIR MONITOR

    EPA Science Inventory

    The USEPA's National Homeland Security Research Center (NHSRC) Technology Testing and Evaluation Program (TTEP) is carrying out performance tests on homeland security technologies. Under TTEP, Battelle evaluated the performance of the Cerex UV Hound point sample air monitor in de...

  19. DEVELOPMENT OF A SUB-SLAB AIR SAMPLING PROTOCOL TO SUPPORT ASSESSMENT OF VAPOR INTRUSION

    EPA Science Inventory

    The primary purpose of this research effort is to develop a methodology for sub-slab sampling to support the EPA guidance and vapor intrusion investigations after vapor intrusion has been established at a site. Methodologies for sub-slab air sampling are currently lacking in ref...

  20. Comparison of stationary and personal air sampling with an air dispersion model for children’s ambient exposure to manganese

    EPA Science Inventory

    Manganese (Mn) is ubiquitous in the environment and essential for normal growth and development, yet excessive exposure can lead to impairments in neurological function. This study modeled ambient Mn concentrations as an alternative to stationary and personal air sampling to asse...

  1. Spectral fingerprinting of polycyclic aromatic hydrocarbons in high-volume ambient air samples by constant energy synchronous luminescence spectroscopy

    USGS Publications Warehouse

    Kerkhoff, M.J.; Lee, T.M.; Allen, E.R.; Lundgren, D.A.; Winefordner, J.D.

    1985-01-01

    A high-volume sampler fitted with a glass-fiber filter and backed by polyurethane foam (PUF) was employed to collect airborne particulate and gas-phase polycylic aromatic hydrocarbons (PAHs) in ambient air. Samples were collected from four sources representing a range of environmental conditions: gasoline engine exhaust, diesel engine exhaust, air near a heavily traveled interstate site, and air from a moderately polluted urban site. Spectral fingerprints of the unseparated particulate and gas-phase samples were obtained by constant energy synchronous luminescence spectroscopy (CESLS). Five major PAHs in the gas-phase extracts were characterized and estimated. The compatibility of a high-volume sampling method using polyurethane foam coupled with CESLS detection is explored for use as a screening technique for PAHs in ambient air. ?? 1985 American Chemical Society.

  2. Venturi air-jet vacuum ejectors for high-volume atmospheric sampling on aircraft platforms

    NASA Technical Reports Server (NTRS)

    Hill, Gerald F.; Sachse, Glen W.; Young, Douglas C.; Wade, Larry O.; Burney, Lewis G.

    1992-01-01

    Documentation of the installation and use of venturi air-jet vacuum ejectors for high-volume atmospheric sampling on aircraft platforms is presented. Information on the types of venturis that are useful for meeting the pumping requirements of atmospheric-sampling experiments is also presented. A description of the configuration and installation of the venturi system vacuum line is included with details on the modifications that were made to adapt a venturi to the NASA Electra aircraft at GSFC, Wallops Flight Facility. Flight test results are given for several venturis with emphasis on applications to the Differential Absorption Carbon Monoxide Measurement (DACOM) system at LaRC. This is a source document for atmospheric scientists interested in using the venturi systems installed on the NASA Electra or adapting the technology to other aircraft.

  3. Does the Exposure of Urine Samples to Air Affect Diagnostic Tests for Urine Acidification?

    PubMed Central

    Yi, Joo-Hark; Shin, Hyun-Jong; Kim, Sun-Moon; Han, Sang-Woong; Oh, Man-Seok

    2012-01-01

    Summary Background and objectives For accurate measurement of pH, urine collection under oil to limit the escape of CO2 on air exposure is recommended. This study aims to test the hypothesis that urine collection under oil is not necessary in acidic urine in which bicarbonate and CO2 are minor buffers, because loss of CO2 would have little effect on its pH. Design, setting, participants, & measurements One hundred consecutive random urine samples were collected under oil and analyzed for pH, pCO2, and HCO3− immediately and after 5 minutes of vigorous shaking in uncovered flasks to allow CO2 escape. Results The pH values in 97 unshaken samples ranged from 5.03 to 6.83. With shaking, urine pCO2 decreased by 76%, whereas urine HCO3− decreased by 60%. Meanwhile, urine baseline median pH (interquartile range) of 5.84 (5.44–6.25) increased to 5.93 (5.50–6.54) after shaking (ΔpH=0.12 [0.07–0.29], P<0.001). ΔpH with pH≤6.0 was significantly lower than the ΔpH with pH>6.0 (0.08 [0.05–0.12] versus 0.36 [0.23–0.51], P<0.001). Overall, the lower the baseline pH, the smaller the ΔpH. Conclusions The calculation of buffer reactions in a hypothetical acidic urine predicted a negligible effect on urine pH on loss of CO2 by air exposure, which was empirically proven by the experimental study. Therefore, exposure of urine to air does not substantially alter the results of diagnostic tests for urine acidification, and urine collection under oil is not necessary. PMID:22700881

  4. Determination of polybrominated diphenyl ethers (PBDEs) in dust samples collected in air conditioning filters of different usage - method development.

    PubMed

    Śmiełowska, M; Zabiegała, B

    2018-06-19

    This study presents the results of studies aimed at the development of an analytical procedure for separation, identification, and determination of PBDEs compounds in dust samples collected from automotive cabin air filters and samples collected from filters installed as part of the air purification system in academic facilities. Ultrasound-assisted dispersive solid phase extraction (UA-dSPE) was found to perform better in terms of extract purification than the conventional SPE technique. GC-EIMS was used for final determination of analytes. The concentrations of PBDEs in car filters ranged from < LOD to 688 ng/g while from < LOD to 247 ng/g in dust from air conditioning filters. BDE-47 and BDE-100 were reported the dominating congeners. The estimated exposure to PBDEs via ingestion of dust from car filters varied from 0.00022 to 0.012 ng/day in toddlers and from 0.000036 to 0.0029 ng/day in adults; dust from air conditioning filters: from 0.017 to 0.25 ng/day in toddlers and from 0.0029 to 0.042 ng/day. In addition, an attempt was made at extracting PBDEs from a dust samples using the matrix solid-phase dispersion (MSPD) technique as a promising alternative to conventional SPE separations. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. High-resolution real-time optical studies of radiological air sample filtration processes in an environmental continuous air monitor

    NASA Astrophysics Data System (ADS)

    Rodgers, John C.; Wasiolek, Piotr T.; Schery, Stephen D.; Alcantara, Raul E.

    1999-01-01

    The need for a continuous air monitor capable of quick and accurate measurements of airborne radioactivity in close proximity to the work environment during waste management, site restoration, and D&D operations led to the Los Alamos National Laboratory development of an environmental continuous air monitor (ECAM). Monitoring the hostile work environment of waste recovery, for example, presents unique challenges for detector design for detectors previously used for the clean room conditions of the typical plutonium laboratory. The environmental and atmospheric conditions (dust, high wind, etc.) influence aerosol particle penetration into the ECAM sampling head as well as the build-up of deposits on the ECAM filter.

  6. Size selective isocyanate aerosols personal air sampling using porous plastic foams

    NASA Astrophysics Data System (ADS)

    Khanh Huynh, Cong; Duc, Trinh Vu

    2009-02-01

    As part of a European project (SMT4-CT96-2137), various European institutions specialized in occupational hygiene (BGIA, HSL, IOM, INRS, IST, Ambiente e Lavoro) have established a program of scientific collaboration to develop one or more prototypes of European personal samplers for the collection of simultaneous three dust fractions: inhalable, thoracic and respirable. These samplers based on existing sampling heads (IOM, GSP and cassettes) use Polyurethane Plastic Foam (PUF) according to their porosity to support sampling and separator size of the particles. In this study, the authors present an original application of size selective personal air sampling using chemical impregnated PUF to perform isocyanate aerosols capturing and derivatizing in industrial spray-painting shops.

  7. Atmospheric CO2 Records from Sites in the Atmospheric Environment Service Air Sampling Network (1975 and 1994)

    DOE Data Explorer

    Trivett, N. B.A. [Atmospheric Environment Service, Downsview, Ontario, Canada; Hudec, V. C. [Atmospheric Environment Service, Downsview, Ontario, Canada; Wong, C. S. [Marine Carbon Research Centre, Institute of Ocean Sciences, Sidney, British Columbia, Canada

    1997-01-01

    From the mid-1970s through the mid-1990s, air samples were collected for the purposes of monitoring atmospheric CO2 from four sites in the AES air sampling network. Air samples were collected approximately once per week, between 12:00 and 16:00 local time, in a pair of evacuated 2-L thick-wall borosilicate glass flasks. Samples were collected under preferred conditions of wind speed and direction (i.e., upwind of the main station and when winds are strong and steady). The flasks were evacuated to pressures of ~1 × 10-4 mbar or 0.01 Pa prior to being sent to the stations. The airwas not dried during sample collection. The flask data from Alert show an increase in the annual atmospheric CO2 concentration from 341.35 parts per million by volume (ppmv) in 1981 to 357.21 ppmv in 1991. For Cape St. James, Trivett and Higuchi (1989) reported that the mean annual rate of increase, obtained from the slope of a least-squares regression line through the annual averages, was 1.43 ppmv per year. In August 1992, the weather station at Cape St. James was automated; as a result, the flask sampling program was discontinued at this site. Estevan Point, on the West Coast of Vancouver Island, was chosen as a replacement station. Sampling at Estevan Point started in 1992; thus, the monthly and annual CO2record from Estevan Point is too short to show any long-term trends. The sampling site at Sable Island, off the coast of Nova Scotia, was established in 1975. The flask data from Sable Island show an increase in the annual atmospheric CO2 concentration from 334.49 parts per million by volume (ppmv) in 1977 (the first full year of data) to 356.02 ppmv in 1990. For Sable Island, Trivett and Higuchi (1989) reported that the mean annual rate of increase, obtained from the slope of a least-squares regression line through the annual averages, was 1.48 ppmv per year.

  8. Analytical method validation for the determination of 2,3,3,3-tetrafluoropropene in air samples using gas chromatography with flame ionization detection.

    PubMed

    Mawn, Michael P; Kurtz, Kristine; Stahl, Deborah; Chalfant, Richard L; Koban, Mary E; Dawson, Barbara J

    2013-01-01

    A new low global warming refrigerant, 2,3,3,3-tetrafluoro propene, or HFO-1234yf, has been successfully evaluated for automotive air conditioning, and is also being evaluated for stationary refrigeration and air conditioning systems. Due to the advantageous environmental properties of HFO-1234yf versus HFC-134a, coupled with its similar physical properties and system performance, HFO-1234yf is also being evaluated to replace HFC-134a in refrigeration applications where neat HFC-134a is currently used. This study reports on the development and validation of a sampling and analytical method for the determination of HFO-1234yf in air. Different collection media were screened for desorption and simulated sampling efficiency with three-section (350/350/350 mg) Anasorb CSC showing the best results. Therefore, air samples were collected using two 3-section Anasorb CSC sorbent tubes in series at 0.02 L/min for up to 8 hr for sample volumes of up to 9.6 L. The sorbent tubes were extracted in methylene chloride, and analyzed by gas chromatography with flame ionization detection. The method was validated from 0.1× to 20× the target level of 0.5 ppm (2.3 mg/m(3)) for a 9.6 L air volume. Desorption efficiencies for HFO-1234yf were 88 to 109% for all replicates over the validation range with a mean overall recovery of 93%. Simulated sampling efficiencies ranged from 87 to 104% with a mean of 94%. No migration or breakthrough to the back tube was observed under the sampling conditions evaluated. HFO-1234yf samples showed acceptable storage stability on Anasorb CSC sorbent up to a period of 30 days when stored under ambient, refrigerated, or frozen temperature conditions.

  9. Measurement results obtained from air quality monitoring system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turzanski, P.K.; Beres, R.

    1995-12-31

    An automatic system of air pollution monitoring operates in Cracow since 1991. The organization, assembling and start-up of the network is a result of joint efforts of the US Environmental Protection Agency and the Cracow environmental protection service. At present the automatic monitoring network is operated by the Provincial Inspection of Environmental Protection. There are in total seven stationary stations situated in Cracow to measure air pollution. These stations are supported continuously by one semi-mobile (transportable) station. It allows to modify periodically the area under investigation and therefore the 3-dimensional picture of creation and distribution of air pollutants within Cracowmore » area could be more intelligible.« less

  10. EPA's National Dioxin Air Monitoring Network (NDAMN): Design, implementation, and final results

    NASA Astrophysics Data System (ADS)

    Lorber, Matthew; Ferrario, Joseph; Byrne, Christian

    2013-10-01

    The U.S. Environmental Protection Agency (U.S. EPA) established the National Dioxin Air Monitoring Network (NDAMN) in June of 1998, and operated it until November of 2004. The objective of NDAMN was to determine background air concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs). NDAMN started with 10 sampling sites, adding more over time until the final count of 34 sites was reached by the beginning of 2003. Samples were taken quarterly, and the final sample count was 685. All samples were measured for 17 PCDD/PCDF congeners, 8 PCDD/PCDF homologue groups, and 7 dl-PCBs (note: 5 additional dl-PCBs were added for samples starting in the summer of 2002; 317 samples had measurements of 12 dl-PCBs). The overall average total toxic equivalent (TEQ) concentration in the United States was 11.2 fg TEQ m-3 with dl-PCBs contributing 0.8 fg TEQ m-3 (7%) to this total. The archetype dioxin and furan background air congener profile was seen in the survey averages and in most individual samples. This archetype profile is characterized by low and similar concentrations for tetra - through hexa PCDD/PCDF congeners, with elevations in four congeners - a hepta dioxin and furan congener, and both octa congeners. Sites were generally categorized as urban (4 sites), rural (23 sites), or remote (7 sites). The average TEQ concentrations over all sites and samples within these categories were: urban = 15.9 fg TEQ m-3, rural = 13.9 fg TEQ m-3, and remote = 1.2 fg TEQ m-3. Rural sites showed elevations during the fall or winter months when compared to the spring or summer months, and the same might be said for urban sites, but the remote sites appear to show little variation over time. The four highest individual moment measurements were 847, 292, 241, and 132 fg TEQ m-3. For the 847 and 292 fg TEQ m-3 samples, the concentrations of all congeners were elevated over their site averages, but for

  11. Analytical results from ground-water sampling using a direct-push technique at the Dover National Test Site, Dover Air Force Base, Delaware, June-July 2001

    USGS Publications Warehouse

    Guertal, William R.; Stewart, Marie; Barbaro, Jeffrey R.; McHale, Timthoy J.

    2004-01-01

    A joint study by the Dover National Test Site and the U.S. Geological Survey was conducted from June 27 through July 18, 2001 to determine the spatial distribution of the gasoline oxygenate additive methyl tert-butyl ether and selected water-quality constituents in the surficial aquifer underlying the Dover National Test Site at Dover Air Force Base, Delaware. The study was conducted to support a planned enhanced bio-remediation demonstration and to assist the Dover National Test Site in identifying possible locations for future methyl tert-butyl ether remediation demonstrations. This report presents the analytical results from ground-water samples collected during the direct-push ground-water sampling study. A direct-push drill rig was used to quickly collect 115 ground-water samples over a large area at varying depths. The ground-water samples and associated quality-control samples were analyzed for volatile organic compounds and methyl tert-butyl ether by the Dover National Test Site analytical laboratory. Volatile organic compounds were above the method reporting limits in 59 of the 115 ground-water samples. The concentrations ranged from below detection limits to maximum values of 12.4 micrograms per liter of cis-1,2-dichloroethene, 1.14 micrograms per liter of trichloroethene, 2.65 micrograms per liter of tetrachloroethene, 1,070 micrograms per liter of methyl tert-butyl ether, 4.36 micrograms per liter of benzene, and 1.8 micrograms per liter of toluene. Vinyl chloride, ethylbenzene, p,m-xylene, and o-xylene were not detected in any of the samples collected during this investigation. Methyl tert-butyl ether was detected in 47 of the 115 ground-water samples. The highest methyl tert-butyl ether concentrations were found in the surficial aquifer from -4.6 to 6.4 feet mean sea level, however, methyl tert-butyl ether was detected as deep as -9.5 feet mean sea level. Increased methane concentrations and decreased dissolved oxygen concentrations were found in

  12. Development of size-selective sampling of Bacillus anthracis surrogate spores from simulated building air intake mixtures for analysis via laser-induced breakdown spectroscopy.

    PubMed

    Gibb-Snyder, Emily; Gullett, Brian; Ryan, Shawn; Oudejans, Lukas; Touati, Abderrahmane

    2006-08-01

    Size-selective sampling of Bacillus anthracis surrogate spores from realistic, common aerosol mixtures was developed for analysis by laser-induced breakdown spectroscopy (LIBS). A two-stage impactor was found to be the preferential sampling technique for LIBS analysis because it was able to concentrate the spores in the mixtures while decreasing the collection of potentially interfering aerosols. Three common spore/aerosol scenarios were evaluated, diesel truck exhaust (to simulate a truck running outside of a building air intake), urban outdoor aerosol (to simulate common building air), and finally a protein aerosol (to simulate either an agent mixture (ricin/anthrax) or a contaminated anthrax sample). Two statistical methods, linear correlation and principal component analysis, were assessed for differentiation of surrogate spore spectra from other common aerosols. Criteria for determining percentages of false positives and false negatives via correlation analysis were evaluated. A single laser shot analysis of approximately 4 percent of the spores in a mixture of 0.75 m(3) urban outdoor air doped with approximately 1.1 x 10(5) spores resulted in a 0.04 proportion of false negatives. For that same sample volume of urban air without spores, the proportion of false positives was 0.08.

  13. Residues of 2, 4-D in air samples from Saskatchewan: 1966-1975.

    PubMed

    Grover, R; Kerr, L A; Wallace, K; Yoshida, K; Maybank, J

    1976-01-01

    Residues of 2,4-D (2,4-dichlorophenoxyacetic acid) in air samples from several sampling sites in central and southern Saskatchewan during the spraying seasons in the 1966-68 and 1970-75 periods were determined by gas-liquid chromatographic techniques. Initially, individual esters of 2,4-D were characterized by retention times and confirmed further by co-injection and dual column procedures. Since 1973, however, only total 2,4-D acid levels in air samples have been determined after esterification to the methyl ester and confirmed by gc/ms techniques whenever possible. Up to 50% of the daily samples collected during the spraying season at any of the locations and during any given year contained 2,4-D, with butyl esters being found most frequently. The daily 24-hr mean atmospheric concentrations of 2,4-D ranged from 0.01 to 1.22 mug/m3, 0.01 to 13.50 mug/m3, and 0.05 to 0.59 mug/m3 for the iso-propyl, mixed butyl and iso-octyl esters, respectively. Even when the samples were analysed for the total 2,4-D content, i.e. from 1973 onwards, the maximum level of the total acid reached only 23.14 mug/m3. In any given year and at any of the sampling sites, about 30% of the samples contained less than 0.01 mug/m3 of 2,4-D. In another 40% of the samples, the levels of 2,4-D ranged from 0.01 to 0.099 mug/m3. Only about 30% of the samples contained 2,4-D concentrations higher than 0.1 mug/m3, with only 10% or less exceeding 1 mug/m3. None of the samples, obtained with the high volume particulate sampler, showed any detectable levels of 2,4-D, indicating little or no transport of 2,4-D adsorbed on dust particles or as crystals of amine salts.

  14. Day and night variation in chemical composition and toxicological responses of size segregated urban air PM samples in a high air pollution situation

    NASA Astrophysics Data System (ADS)

    Jalava, P. I.; Wang, Q.; Kuuspalo, K.; Ruusunen, J.; Hao, L.; Fang, D.; Väisänen, O.; Ruuskanen, A.; Sippula, O.; Happo, M. S.; Uski, O.; Kasurinen, S.; Torvela, T.; Koponen, H.; Lehtinen, K. E. J.; Komppula, M.; Gu, C.; Jokiniemi, J.; Hirvonen, M.-R.

    2015-11-01

    Urban air particulate pollution is a known cause for adverse human health effects worldwide. China has encountered air quality problems in recent years due to rapid industrialization. Toxicological effects induced by particulate air pollution vary with particle sizes and season. However, it is not known how distinctively different photochemical activity and different emission sources during the day and the night affect the chemical composition of the PM size ranges and subsequently how it is reflected to the toxicological properties of the PM exposures. The particulate matter (PM) samples were collected in four different size ranges (PM10-2.5; PM2.5-1; PM1-0.2 and PM0.2) with a high volume cascade impactor. The PM samples were extracted with methanol, dried and thereafter used in the chemical and toxicological analyses. RAW264.7 macrophages were exposed to the particulate samples in four different doses for 24 h. Cytotoxicity, inflammatory parameters, cell cycle and genotoxicity were measured after exposure of the cells to particulate samples. Particles were characterized for their chemical composition, including ions, element and PAH compounds, and transmission electron microscopy (TEM) was used to take images of the PM samples. Chemical composition and the induced toxicological responses of the size segregated PM samples showed considerable size dependent differences as well as day to night variation. The PM10-2.5 and the PM0.2 samples had the highest inflammatory potency among the size ranges. Instead, almost all the PM samples were equally cytotoxic and only minor differences were seen in genotoxicity and cell cycle effects. Overall, the PM0.2 samples had the highest toxic potential among the different size ranges in many parameters. PAH compounds in the samples and were generally more abundant during the night than the day, indicating possible photo-oxidation of the PAH compounds due to solar radiation. This was reflected to different toxicity in the PM

  15. National Air Toxic Assessments (NATA) Results

    EPA Pesticide Factsheets

    The National Air Toxics Assessment was conducted by EPA in 2002 to assess air toxics emissions in order to identify and prioritize air toxics, emission source types and locations which are of greatest potential concern in terms of contributing to population risk. This data source provides downloadable information on emissions at the state, county and census tract level.

  16. Concentrations of particulates in ambient air, gaseous elementary mercury (GEM), and particulate-bound mercury (Hg(p)) at a traffic sampling site: a study of dry deposition in daytime and nighttime.

    PubMed

    Fang, Guor-Cheng; Lin, Yen-Heng; Chang, Chia-Ying; Zheng, Yu-Cheng

    2014-08-01

    In this investigation, the concentrations of particles in ambient air, gaseous elemental mercury (GEM), and particulate-bound mercury (Hg(p)) in total suspended particulates (TSP) as well as dry deposition at a (Traffic) sampling site at Hung-kuang were studied during the day and night in 2012. The results reveal that the mean concentrations of TSP in ambient air, GEM, and Hg(p) were 69.72 μg/m(3), 3.17, and 0.024 ng/m(3), respectively, at the Hung-kuang (Traffic) sampling site during daytime sampling periods. The results also reveal that the mean rates of dry deposition of particles from ambient air and Hg(p) were 145.20 μg/m(2) min and 0.022 ng/m(2) min, respectively, at the Hung-kuang (Traffic) sampling site during the daytime sampling period. The mean concentrations of TSP in ambient air, GEM, and Hg(p) were 60.56 μg/m(3), 2.74, and 0.018 ng/m(3), respectively, at the Hung-kuang (Traffic) sampling site during the nighttime sampling period. The mean rates of dry deposition of particles and Hg(p) from ambient air were 132.58 μg/m(2) min and 0.016 ng/m(2) min, respectively, at the Hung-kuang (Traffic) sampling site during the nighttime sampling period.

  17. Measurements of CO2 Mole Fractionand δ13C in Archived Air Samples from Cape Meares, Oregon (USA) 1977 - 1998

    NASA Astrophysics Data System (ADS)

    Clark, O.; Rice, A. L.

    2017-12-01

    Carbon dioxide (CO2) is the most abundant, anthropogenically forced greenhouse gas (GHG) in the global atmosphere. Emissions of CO2 account for approximately 75% of the world's total GHG emissions. Atmospheric concentrations of CO2 are higher now than they've been at any other time in the past 800,000 years. Currently, the global mean concentration exceeds 400 ppm. Today, global networks regularly monitor CO2 concentrations and isotopic composition (δ13C and δ18O). However, past data is sparse. Over 200 ambient air samples from Cape Meares, Oregon (45.5°N, 124.0°W), a coastal site in Western United States, were obtained by researchers at Oregon Institute of Science and Technology (OGI, now Oregon Health & Science University), between the years of 1977 and 1998 as part of a global monitoring program of six different sites in the polar, middle, and tropical latitudes of the Northern and Southern Hemispheres. Air liquefaction was used to compress approximately 1000L of air (STP) to 30bar, into 33L electropolished (SUMMA) stainless steel canisters. Select archived air samples from the original network are maintained at Portland State University (PSU) Department of Physics. These archived samples are a valuable look at changing atmospheric concentrations of CO2 and δ13C, which can contribute to a better understanding of changes in sources during this time. CO2 concentrations and δ13C of CO2 were measured at PSU, with a Picarro Cavity Ringdown Spectrometer, model G1101-i analytical system. This study presents the analytical methods used, calibration techniques, precision, and reproducibility. Measurements of select samples from the archive show rising CO2 concentrations and falling δ13C over the 1977 to 1998 period, compatible with previous observations and rising anthropogenic sources of CO2. The resulting data set was statistically analyzed in MATLAB. Results of preliminary seasonal and secular trends from the archive samples are presented.

  18. Tank vapor characterization project. Headspace vapor characterization of Hanford waste tank 241-BY-108: Second comparison study results from samples collected on 3/28/96

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, B.L.; Pool, K.H.; Evans, J.C.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of waste storage tank 241-BY-108 (Tank BY-108) at the Hanford Site in Washington State. The results described in this report is the second in a series comparing vapor sampling of the tank headspace using the Vapor Sampling System (VSS) and In Situ Vapor Sampling (ISVS) system without high efficiency particulate air (HEPA) prefiltration. The results include air concentrations of water (H{sub 2}O) and ammonia (NH{sub 3}), permanent gases, total non-methane organic compounds (TO-12), and individual organic analytes collected in SUMMA{trademark} canisters and on triple sorbent traps (TSTs).more » Samples were collected by Westinghouse Hanford Company (WHC) and analyzed by Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volume measurements provided by WHC.« less

  19. Marine Technician's Handbook, Instructions for Taking Air Samples on Board Ship: Carbon Dioxide Project.

    ERIC Educational Resources Information Center

    Keeling, Charles D.

    This booklet is one of a series intended to provide explicit instructions for the collection of oceanographic data and samples at sea. The methods and procedures described have been used by the Scripps Institution of Oceanography and found reliable and up-to-date. Instructions are given for taking air samples on board ship to determine the…

  20. Water- and air-quality monitoring of the Sweetwater Reservoir Watershed, San Diego County, California-Phase One results, continued, 1999-2001

    USGS Publications Warehouse

    Mendez, Gregory O.; Foreman, William T.; Sidhu, Jagdeep S.; Majewski, Michael S.

    2007-01-01

    In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to assess the overall health of the Sweetwater watershed with respect to chemical contamination. The study included regular sampling of air and water at Sweetwater Reservoir for chemical contaminants, including volatile organic compounds, polycyclic aromatic hydrocarbons, pesticides, and major and trace elements. Background water samples were collected at Loveland Reservoir for volatile organic compounds and pesticides. The purpose of this study was to monitor changes in contaminant composition and concentration in the air and water resulting from the construction and operation of State Route 125 near Sweetwater Reservoir. To accomplish this, the study was divided into two phases. Phase One sampling was designed to establish baseline conditions for target compounds in terms of detection frequency and concentration in air and water. Phase Two sampling is planned to continue at the established monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment project may have on the water quality in the reservoir. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as low-use pesticides, trace metals, and wastewater compounds. This report describes the study design, and the sampling and analytical methods, and presents the results for the second and third years of the study (October 1999 to September 2001). Data collected during the first year of sampling (October 1998 to September 1999) were published in 2002.

  1. Irreversible sorption of trace concentrations of perfluorocarboxylic acids to fiber filters used for air sampling

    NASA Astrophysics Data System (ADS)

    Arp, Hans Peter H.; Goss, Kai-Uwe

    Due to the apparent environmental omnipresence of perfluorocarboxylic acids (PFAs), an increasing number of researchers are investigating their ambient particle- and gas-phase concentrations. Typically this is done using a high-volume air sampler equipped with Quartz Fiber Filters (QFFs) or Glass Fiber Filters (GFFs) to sample the particle-bound PFAs and downstream sorbents to sample the gas-phase PFAs. This study reports that at trace, ambient concentrations gas-phase PFAs sorb to QFFs and GFFs irreversibly and hardly pass through these filters to the downstream sorbents. As a consequence, it is not possible to distinguish between particle- and gas-phase concentrations, or to distinguish concentrations on different particle size fractions, unless precautions are taken. Failure to take such precautions could have already caused reported data to be misinterpreted. Here it is also reported that deactivating QFFs and GFFs with a silylating agent renders them suitable for sampling PFAs. Based on the presented study, a series of recommendations for air-sampling PFAs are provided.

  2. Comparison of Air Impaction and Electrostatic Dust Collector Sampling Methods to Assess Airborne Fungal Contamination in Public Buildings.

    PubMed

    Normand, Anne-Cécile; Ranque, Stéphane; Cassagne, Carole; Gaudart, Jean; Sallah, Kankoé; Charpin, Denis-André; Piarroux, Renaud

    2016-03-01

    Many ailments can be linked to exposure to indoor airborne fungus. However, obtaining a precise measurement of airborne fungal levels is complicated partly due to indoor air fluctuations and non-standardized techniques. Electrostatic dust collector (EDC) sampling devices have been used to measure a wide range of airborne analytes, including endotoxins, allergens, β-glucans, and microbial DNA in various indoor environments. In contrast, viable mold contamination has only been assessed in highly contaminated environments such as farms and archive buildings. This study aimed to assess the use of EDCs, compared with repeated air-impactor measurements, to assess airborne viable fungal flora in moderately contaminated indoor environments. Indoor airborne fungal flora was cultured from EDCs and daily air-impaction samples collected in an office building and a daycare center. The quantitative fungal measurements obtained using a single EDC significantly correlated with the cumulative measurement of nine daily air impactions. Both methods enabled the assessment of fungal exposure, although a few differences were observed between the detected fungal species and the relative quantity of each species. EDCs were also used over a 32-month period to monitor indoor airborne fungal flora in a hospital office building, which enabled us to assess the impact of outdoor events (e.g. ground excavations) on the fungal flora levels on the indoor environment. In conclusion, EDC-based measurements provided a relatively accurate profile of the viable airborne flora present during a sampling period. In particular, EDCs provided a more representative assessment of fungal levels compared with single air-impactor sampling. The EDC technique is also simpler than performing repetitive air-impaction measures over the course of several consecutive days. EDC is a versatile tool for collecting airborne samples and was efficient for measuring mold levels in indoor environments. © The Author 2015

  3. Atmospheric CO2 Records from Sites in the Main Geophysical Observatory Air Sampling Network (1983 - 1993)

    DOE Data Explorer

    Brounshtein, A. M. [Main Geophysical Observatory, St. Petersburg, Russia; Shaskov, A. A. [Main Geophysical Observatory, St. Petersburg, Russia; Paramonova, N. N. [Main Geophysical Observatory, St. Petersburg, Russia; Privalov, V. I. [Main Geophysical Observatory, St. Petersburg, Russia; Starodubtsev, Y. A. [Main Geophysical Observatory, St. Petersburg, Russia

    1997-01-01

    Air samples were collected from five sites in the Main Geophysical Observatory air sampling network to monitor the atmospheric CO2 from 1983 - 1993. Airwas collected generally four times per month in pairs of 1.5-L stainless steel electropolished flasks with one greaseless stainless steel stopcock. Sampling was performed by opening the stopcock of the flasks, which have been evacuated at the central laboratory at the Main Geophysical Observatory (MGO). The air was not dried during sample collection. Attempts were made to obtain samples when the wind speed was >5 m/s and the wind direction corresponded to the predetermined "clean air" sector. The period of record at Bering Island is too short to identify any long-term trends in atmospheric CO2 concentrations; however, the yearly mean atmospheric CO2 concentration at Bering Island rose from approximately 346 parts per million by volume (ppmv) in 1986 to 362.6 ppmv in 1993. Measurements from this station are considered indicative of maritime air masses. The period of record at Kotelny Island is too short to identify any long-term trends in atmospheric CO2 concentrations; however, the yearly mean atmospheric CO2 concentration at Kotelny Island rose from 356.08 parts per million by volume (ppmv) in 1988 to 358.8 ppmv in 1993. Because Kotelny Island is the northernmost Russian sampling site, measurements from this site serve as a useful comparison to other northern sites (e.g., Alert, Northwest Territories). In late 1989, air sampling began at the Russian site of Kyzylcha, located in the Republic of Uzbekistan. Unfortunately, the desert site at Kyzylcha has been out of operation since mid-1991 due to financial difficulties in Russia. The annual mean value of 359.02 parts per million by volume (ppmv) for 1990, the lone full year of operation, is higher than measurements from other monitoring programs at this latitude [e.g., Niwot Ridge (354.7 ppmv in 1990) and Tae-ahn Peninsula]. Station "C," an open ocean site, in the

  4. A novel personal air sampling device for collecting volatile organic compounds: a comparison to charcoal tubes and diffusive badges.

    PubMed

    Rossner, Alan; Farant, Jean-Pierre

    2004-02-01

    Evacuated canisters have been used for many years to collect ambient air samples for gases and vapors. Recently, significant interest has arisen in using evacuated canisters for personal breathing zone sampling as an alternative to sorbent sampling. A novel flow control device was designed and built at McGill University. The flow control device was designed to provide a very low flow rate, <0.5 mL/min, to allow a sample to be collected over an extended period of time. Previous experiments run at McGill have shown agreement between the mathematical and empirical models to predict flow rate. The flow control device combined with an evacuated canister (capillary flow control-canister) was used in a series of experiments to evaluate its performance against charcoal tubes and diffusive badges. Air samples of six volatile organic compounds were simultaneously collected in a chamber using the capillary flow control-canister, charcoal tubes, and diffusive badges. Five different concentrations of the six volatile organic compounds were evaluated. The results from the three sampling devices were compared to each other and to concentration values obtained using an online gas chromatograph (GC). Eighty-four samples of each method were collected for each of the six chemicals. Results indicate that the capillary flow control-canister device compares quite favorably to the online GC and to the charcoal tubes, p > 0.05 for most of the tests. The capillary flow control-canister was found to be more accurate for the compounds evaluated, easier to use, and easier to analyze than charcoal tubes and passive dosimeter badges.

  5. CRUMP 2003 Selected Water Sample Results

    EPA Pesticide Factsheets

    Point locations and water sampling results performed in 2003 by the Church Rock Uranium Monitoring Project (CRUMP) a consortium of organizations (Navajo Nation Environmental Protection Agency, US Environmental Protection Agency, New Mexico Scientific Laboratory Division, Navajo Tribal Utility Authority and NM Water Quality Control Commission). Samples include general description of the wells sampled, general chemistry, heavy metals and aestheic parameters, and selected radionuclides. Here only six sampling results are presented in this point shapefile, including: Gross Alpha (U-Nat Ref.) (pCi/L), Gross Beta (Sr/Y-90 Ref.) (pCi/L), Radium-226 (pCi/L), Radium-228 (pCi/L), Total Uranium (pCi/L), and Uranium mass (ug/L). The CRUMP samples were collected in the area of Churchrock, NM in the Eastern AUM Region of the Navajo Nation.

  6. Comparison of Passive and Active Air Sampling (PAAS) Methods for PCBs – A Pilot Study in New York City Schools

    EPA Science Inventory

    PCBs were used extensively in school building materials (caulk and lighting fixture ballasts) during the approximate period of 1950-1978. Most of the schools built nationwide during this period have not had indoor air sampling conducted for PCBs. Passive air sampling holds promi...

  7. Collection and Extraction of Occupational Air Samples for Analysis of Fungal DNA.

    PubMed

    Lemons, Angela R; Lindsley, William G; Green, Brett J

    2018-05-02

    Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several limitations that have resulted in the exclusion of many species. Advances in the field over the last two decades have led occupational health researchers to turn to molecular-based approaches for identifying fungal hazards. These methods have resulted in the detection of many species within indoor and occupational environments that have not been detected using traditional methods. This protocol details an approach for determining fungal diversity within air samples through genomic DNA extraction, amplification, sequencing, and taxonomic identification of fungal internal transcribed spacer (ITS) regions. ITS sequencing results in the detection of many fungal species that are either not detected or difficult to identify to species level using culture or microscopy. While these methods do not provide quantitative measures of fungal burden, they offer a new approach to hazard identification and can be used to determine overall species richness and diversity within an occupational environment.

  8. Mathematical estimation of the level of microbial contamination on spacecraft surfaces by volumetric air sampling

    NASA Technical Reports Server (NTRS)

    Oxborrow, G. S.; Roark, A. L.; Fields, N. D.; Puleo, J. R.

    1974-01-01

    Microbiological sampling methods presently used for enumeration of microorganisms on spacecraft surfaces require contact with easily damaged components. Estimation of viable particles on surfaces using air sampling methods in conjunction with a mathematical model would be desirable. Parameters necessary for the mathematical model are the effect of angled surfaces on viable particle collection and the number of viable cells per viable particle. Deposition of viable particles on angled surfaces closely followed a cosine function, and the number of viable cells per viable particle was consistent with a Poisson distribution. Other parameters considered by the mathematical model included deposition rate and fractional removal per unit time. A close nonlinear correlation between volumetric air sampling and airborne fallout on surfaces was established with all fallout data points falling within the 95% confidence limits as determined by the mathematical model.

  9. Dynamic planar solid phase microextraction-ion mobility spectrometry for rapid field air sampling and analysis of illicit drugs and explosives.

    PubMed

    Guerra-Diaz, Patricia; Gura, Sigalit; Almirall, José R

    2010-04-01

    A preconcentration device that targets the volatile chemical signatures associated with illicit drugs and explosives (high and low) has been designed to fit in the inlet of an ion mobility spectrometer (IMS). This is the first reporting of a fast and sensitive method for dynamic sampling of large volumes of air using planar solid phase microextraction (PSPME) incorporating a high surface area for absorption of analytes onto a sol-gel polydimethylsiloxane (PDMS) coating for direct thermal desorption into an IMS. This device affords high extraction efficiencies due to strong retention properties at ambient temperature, resulting in the detection of analyte concentrations in the parts per trillion range when as low as 3.5 L of air are sampled over the course of 10 s (absolute mass detection of less than a nanogram). Dynamic PSPME was used to sample the headspace over the following: 3,4-methylenedioxymethamphetamine (MDMA) tablets resulting in the detection of 12-40 ng of piperonal, high explosives (Pentolite) resulting in the detection of 0.6 ng of 2,4,6-trinitrotoluene (TNT), and low explosives (several smokeless powders) resulting in the detection of 26-35 ng of 2,4-dinitrotoluene (2,4-DNT) and 11-74 ng of diphenylamine (DPA).

  10. Potential contamination of shipboard air samples by diffusive emissions of PCBs and other organic pollutants: implications and solutions.

    PubMed

    Lohmann, Rainer; Jaward, Foday M; Durham, Louise; Barber, Jonathan L; Ockenden, Wendy; Jones, Kevin C; Bruhn, Regina; Lakaschus, Soenke; Dachs, Jordi; Booij, Kees

    2004-07-15

    Air samples were taken onboard the RRS Bransfield on an Atlantic cruise from the United Kingdom to Halley, Antarctica, from October to December 1998, with the aim of establishing PCB oceanic background air concentrations and assessing their latitudinal distribution. Great care was taken to minimize pre- and post-collection contamination of the samples, which was validated through stringent QA/QC procedures. However, there is evidence that onboard contamination of the air samples occurred,following insidious, diffusive emissions on the ship. Other data (for PCBs and other persistent organic pollutants (POPs)) and examples of shipboard contamination are presented. The implications of these findings for past and future studies of global POPs distribution are discussed. Recommendations are made to help critically appraise and minimize the problems of insidious/diffusive shipboard contamination.

  11. Development of a wireless air pollution sensor package for aerial-sampling of emissions

    EPA Science Inventory

    A new sensor system for mobile and aerial emission sampling was developed for open area pollutant sources, such as prescribed forest burns. The sensor system, termed “Kolibri”, consists of multiple low-cost air quality sensors measuring CO2, CO, samplers for particulate matter wi...

  12. Atmospheric Carbon Dioxide Mixing Ratios from the NOAA CMDL Carbon Cycle Cooperative Global Air Sampling Network (2009)

    DOE Data Explorer

    Conway, Thomas [NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, CO (USA); Tans, Pieter [NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, CO (USA)

    2009-01-01

    The National Oceanic and Atmospheric Administration's Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) has measured CO2 in air samples collected weekly at a global network of sites since the late 1960s. Atmospheric CO2 mixing ratios reported in these files were measured by a nondispersive infrared absorption technique in air samples collected in glass flasks. All CMDL flask samples are measured relative to standards traceable to the World Meteorological Organization (WMO) CO2 mole fraction scale. These measurements constitute the most geographically extensive, carefully calibrated, internally consistent atmospheric CO2 data set available and are essential for studies aimed at better understanding the global carbon cycle budget.

  13. Concentration and characteristics of depleted uranium in water, air and biological samples collected in Serbia and Montenegro.

    PubMed

    Jia, Guogang; Belli, Maria; Sansone, Umberto; Rosamilia, Silvia; Gaudino, Stefania

    2005-09-01

    During the Balkan conflicts, in 1995 and 1999, depleted uranium (DU) rounds were employed and were left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Serbia and Montenegro, radiological surveys of DU in water, air and biological samples were carried out over the period 27 October-5 November 2001. The uranium isotopic concentrations in biological samples collected in Serbia and Montenegro, mainly lichens and barks, were found to be in the range of 0.67-704 Bqkg(-1) for (238)U, 0.48-93.9 Bqkg(-1) for (234)U and 0.02-12.2 Bqkg(-1) for (235)U, showing uranium levels to be higher than in the samples collected at the control sites. Moreover, (236)U was detectable in some of the samples. The isotopic ratios of (234)U/(238)U showed DU to be detectable in many biological samples at all examined sites, especially in Montenegro, indicating widespread ground-surface DU contamination, albeit at very low level. The uranium isotopic concentrations in air obtained from the air filter samples collected in Serbia and Montenegro were found to be in the range of 1.99-42.1 microBqm(-3) for (238)U, 0.96-38.0 microBqm(-3) for (234)U, and 0.05-1.83 microBqm(-3) for (235)U, being in the typical range of natural uranium values. Thus said, most of the air samples are DU positive, this fact agreeing well with the widespread DU contamination detected in the biological samples. The uranium concentrations in water samples collected in Serbia and Montenegro were found to be in the range of 0.40-21.9 mBql(-1) for (238)U, 0.27-28.1 mBql(-1) for (234)U, and 0.01-0.88 mBql(-1) for (235)U, these values being much lower than those in mineral water found in central Italy and below the WHO guideline for drinking water. From a radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated

  14. New approach to resolve the humidity problem in VOC determination in outdoor air samples using solid adsorbent tubes followed by TD-GC-MS.

    PubMed

    Maceira, Alba; Vallecillos, Laura; Borrull, Francesc; Marcé, Rosa Maria

    2017-12-01

    This study describes the humidity effect in the sampling process by adsorbent tubes followed by thermal desorption and gas chromatography-mass spectrometry (TD-GC-MS) for the determination of volatile organic compounds (VOCs) in air samples and evaluates possible solutions to this problem. Two multi-sorbent bed tubes, Tenax TA/Carbograph 1TD and Carbotrap B/Carbopack X/Carboxen 569, were tested in order to evaluate their behaviour in the presence of environmental humidity. Humidity problems were demonstrated with carbon-based tubes, while Tenax-based tubes did not display any influence. Silica gel, a molecular sieve and CaCl 2 were tried out as materials for drying tube to remove air humidity, placed prior to the sampling tube to prevent water from entering. The pre-tubes filled with 0.5g of CaCl 2 showed the best results with respect to their blanks, the analytes recoveries and their ability to remove ambient humidity. To avoid the possible agglomeration of CaCl 2 during the sampling process in high relative humidity atmospheres, 0.1g of diatomaceous earth were mixed with the desiccant agent. The applicability of the CaCl 2 pre-tube as drying agent prior to Carbotrap B/Carbopack X/Carboxen 569 tubes was tested in urban and industrial locations with samplings of air at high relative humidity. In addition, the results were compared with those obtained using Tenax TA/Carbograph 1TD tubes. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Estimating Sampling Biases and Measurement Uncertainties of AIRS-AMSU-A Temperature and Water Vapor Observations Using MERRA Reanalysis

    NASA Technical Reports Server (NTRS)

    Hearty, Thomas J.; Savtchenko, Andrey K.; Tian, Baijun; Fetzer, Eric; Yung, Yuk L.; Theobald, Michael; Vollmer, Bruce; Fishbein, Evan; Won, Young-In

    2014-01-01

    We use MERRA (Modern Era Retrospective-Analysis for Research Applications) temperature and water vapor data to estimate the sampling biases of climatologies derived from the AIRS/AMSU-A (Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit-A) suite of instruments. We separate the total sampling bias into temporal and instrumental components. The temporal component is caused by the AIRS/AMSU-A orbit and swath that are not able to sample all of time and space. The instrumental component is caused by scenes that prevent successful retrievals. The temporal sampling biases are generally smaller than the instrumental sampling biases except in regions with large diurnal variations, such as the boundary layer, where the temporal sampling biases of temperature can be +/- 2 K and water vapor can be 10% wet. The instrumental sampling biases are the main contributor to the total sampling biases and are mainly caused by clouds. They are up to 2 K cold and greater than 30% dry over mid-latitude storm tracks and tropical deep convective cloudy regions and up to 20% wet over stratus regions. However, other factors such as surface emissivity and temperature can also influence the instrumental sampling bias over deserts where the biases can be up to 1 K cold and 10% wet. Some instrumental sampling biases can vary seasonally and/or diurnally. We also estimate the combined measurement uncertainties of temperature and water vapor from AIRS/AMSU-A and MERRA by comparing similarly sampled climatologies from both data sets. The measurement differences are often larger than the sampling biases and have longitudinal variations.

  16. CTEPP STANDARD OPERATING PROCEDURE FOR COLLECTION OF FIXED SITE INDOOR AND OUTDOOR AIR SAMPLES FOR PERSISTENT ORGANIC POLLUTANTS (SOP-2.12)

    EPA Science Inventory

    This SOP describes the procedures to set up, calibrate, initiate and terminate air sampling for persistent organic pollutants. This method is used to sample air, indoors and outdoors, at homes and at day care centers over a 48-hr period.

  17. Evaluation of sampling methods for toxicological testing of indoor air particulate matter.

    PubMed

    Tirkkonen, Jenni; Täubel, Martin; Hirvonen, Maija-Riitta; Leppänen, Hanna; Lindsley, William G; Chen, Bean T; Hyvärinen, Anne; Huttunen, Kati

    2016-09-01

    There is a need for toxicity tests capable of recognizing indoor environments with compromised air quality, especially in the context of moisture damage. One of the key issues is sampling, which should both provide meaningful material for analyses and fulfill requirements imposed by practitioners using toxicity tests for health risk assessment. We aimed to evaluate different existing methods of sampling indoor particulate matter (PM) to develop a suitable sampling strategy for a toxicological assay. During three sampling campaigns in moisture-damaged and non-damaged school buildings, we evaluated one passive and three active sampling methods: the Settled Dust Box (SDB), the Button Aerosol Sampler, the Harvard Impactor and the National Institute for Occupational Safety and Health (NIOSH) Bioaerosol Cyclone Sampler. Mouse RAW264.7 macrophages were exposed to particle suspensions and cell metabolic activity (CMA), production of nitric oxide (NO) and tumor necrosis factor (TNFα) were determined after 24 h of exposure. The repeatability of the toxicological analyses was very good for all tested sampler types. Variability within the schools was found to be high especially between different classrooms in the moisture-damaged school. Passively collected settled dust and PM collected actively with the NIOSH Sampler (Stage 1) caused a clear response in exposed cells. The results suggested the higher relative immunotoxicological activity of dust from the moisture-damaged school. The NIOSH Sampler is a promising candidate for the collection of size-fractionated PM to be used in toxicity testing. The applicability of such sampling strategy in grading moisture damage severity in buildings needs to be developed further in a larger cohort of buildings.

  18. Determination of sub-part-per-million levels of formaldehyde in air using active or passive sampling on 2,4-dinitrophenylhydrazine-coated glass fiber filters and high-performance liquid chromatography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levin, J.O.; Andersson, K.; Lindahl, R.

    1985-05-01

    Formaldehyde is sampled from air with the use of a standard miniature glass fiber filter impregnated with 2,4-dinitrophenylhydrazine and phosphoric acid. The formaldehyde hydrazone is desorbed from the filter with acetonitrile and determined by high-performance liquid chromatography using UV detection at 365 nm. Recovery of gas-phase-generated formaldehyde as hydrazone from a 13-mm impregnated filter is 80-100% in the range 0.3-30 ..mu..g of formaldehyde. This corresponds to 0.1-10 mg/m/sup 3/ in a 3-L air sample. When the filter sampling system is used in the active mode, air can be sampled at a rate of up to 1 L/min, affording an overallmore » sensitivity of about 1 ..mu..g/m/sup 3/ based on a 60-L air sample. Results are given from measurements of formaldehyde in indoor air. The DNP-coated filters were also evaluated for passive sampling. In this case 37-mm standard glass fibers were used and the sampling rate was 55-65 mL/min in two types of dosimeters. The diffusion samplers are especially useful for personal exposure monitoring in the work environment. 24 references, 2 figures, 4 tables.« less

  19. Cryogenic separation of an oxygen-argon mixture in natural air samples for the determination of isotope and molecular ratios.

    PubMed

    Keedakkadan, Habeeb Rahman; Abe, Osamu

    2015-04-30

    The separation and purification of oxygen-argon mixtures are critical in the high-precision analysis of Δ(17) O and δ(O2 /Ar) for geochemical applications. At present, chromatographic methods are used for the separation and purification of oxygen-argon mixtures or pure oxygen, but these methods require the use of high-purity helium as a carrier gas. Considerable interest has been expressed in the development of a helium-free cryogenic separation of oxygen-argon mixtures in natural air samples. The precise and simplified cryogenic separation of oxygen-argon mixtures from natural air samples presented here was made possible using a single 5A (30/60 mesh) molecular sieve column. The method involves the trapping of eluted gases using molecular sieves at liquid nitrogen temperature, which is associated with isotopic fractionation. We tested the proposed method for the determination of isotopic fractionations during the gas exchange between water and atmospheric air at equilibrium. The dependency of fractionation was studied at different water temperatures and for different methods of equilibration (bubbling and stirring). Isotopic and molecular fractionations during gas desorption from molecular sieves were studied for different amounts and types of molecular sieves. Repeated measurements of atmospheric air yielded a reproducibility (±SD) of 0.021 ‰, 0.044 ‰, 15 per meg and 1.9 ‰ for δ(17) O, δ(18) O, Δ(17) O and δ(O2 /Ar) values, respectively. We applied the method to determine equilibrium isotope fractionation during gas exchange between air and water. Consistent δ(18) O and Δ(17) O results were obtained with the latest two studies, whereas there was a significant difference in δ(18) O values between seawater and deionized water. We have revised a helium-free, cryogenic separation of oxygen-argon mixtures in natural air samples for isotopic and molecular ratio analysis. The use of a single 13X (1/8" pellet) molecular sieve yielded the smallest isotopic

  20. Soyuz 22 Return Samples: Assessment of Air Quality Aboard the International Space Station

    NASA Technical Reports Server (NTRS)

    Jams, John T.

    2010-01-01

    Three mini-grab sample containers (m-GSCs) were returned aboard Soyuz 22 because of concerns that new air pollutants were present in the air and these were getting into the water recovery system. The Total Organic Carbon Analyzer had been giving increasing readings of total organic carbon (TOC) in the potable water, and it was postulated that an increased load into the system was responsible. The toxicological assessment of 3 m-GSCs from the ISS is shown in Table 1. The recoveries of the 3 standards (as listed above) from the GSCs averaged 103, 95 and 76%, respectively. Recovery from formaldehyde control badges were 90 and 91%.

  1. Sampling of trace volatile metal(loid) compounds in ambient air using polymer bags: a convenient method.

    PubMed

    Haas, K; Feldmann, J

    2000-09-01

    results, Tedlar bags could even be used, with some limitations, for long-term sampling of air containing traces of VOMs. The loss is more pronounced at higher temperatures.

  2. From Results to Action - Implementing an Indoor Air Quality Pilot Project

    NASA Astrophysics Data System (ADS)

    Collier, A. M.; Ware, G. E.; Iwasaki, P. G.; Billingsley, L. R.; Main, D.; Hannigan, M.; Pfotenhauer, D.

    2016-12-01

    One of the key differences between community-based participatory research (CBPR) and more conventional scientific research is the expectation that a project does not end with finalized results, but rather with taking action based on those results. Using an indoor air quality pilot project as an example, we will discuss how the consideration of potential actions and applications for the project findings should be integrated into planning throughout the life of a project. We will also share general reflections on effective CBPR from the perspective of both science and community partners on the project. In 2015, Taking Neighborhood Health to Heart (TNH2H), a community-based organization in Northeast Denver, researchers from the University of Colorado, Boulder, and AGU's Thriving Earth Exchange partnered to conduct a pilot project investigating indoor air quality in a Denver community. This partnership formed in response to community concerns about potential environmental contamination from dry cleaning operations, specifically through spills of the compound perchloroethylene. The exploration of the presence of radon, another indoor air quality concern common across the state of Colorado, was also added to the project. Using an iterative process, the team designed a sampling plan, selected a target location, and recruited homes and residents to participate in the pilot project. Radon and perchloroethylene data were then collected in 15 homes. Following data collection, results were first shared with project participants, after which de-identified data were shared with the members of TNH2H. Together TNH2H and researchers then developed strategies for public dissemination of the project findings. While we did not find levels of percholorethylene above the `action level' in any of the participating homes; however, we did find more frequent occurrences of radon levels above the `action level' than we had anticipated. For example, 80% of the homes in our study had radon

  3. An analytical method for trifluoroacetic Acid in water and air samples using headspace gas chromatographic determination of the methyl ester.

    PubMed

    Zehavi, D; Seiber, J N

    1996-10-01

    An analytical method has been developed for the determination of trace levels of trifluoroacetic acid (TFA), an atmospheric breakdown product of several of the hydrofluorocarbon (HFC) and hydrochlorofluorocarbon (HCFC) replacements for the chlorofluorocarbon (CFC) refrigerants, in water and air. TFA is derivatized to the volatile methyl trifluoroacetate (MTFA) and determined by automated headspace gas chromatography (HSGC) with electron-capture detection or manual HSGC using GC/MS in the selected ion monitoring (SIM) mode. The method is based on the reaction of an aqueous sample containing TFA with dimethyl sulfate (DMS) in concentrated sulfuric acid in a sealed headspace vial under conditions favoring distribution of MTFA to the vapor phase. Water samples are prepared by evaporative concentration, during which TFA is retained as the anion, followed by extraction with diethyl ether of the acidified sample and then back-extraction of TFA (as the anion) in aqueous bicarbonate solution. The extraction step is required for samples with a relatively high background of other salts and organic materials. Air samples are collected in sodium bicarbonate-glycerin-coated glass denuder tubes and prepared by rinsing the denuder contents with water to form an aqueous sample for derivatization and analysis. Recoveries of TFA from spiked water, with and without evaporative concentration, and from spiked air were quantitative, with estimated detection limits of 10 ng/mL (unconcentrated) and 25 pg/mL (concentrated 250 mL:1 mL) for water and 1 ng/m(3) (72 h at 5 L/min) for air. Several environmental air, fogwater, rainwater, and surface water samples were successfully analyzed; many showed the presence of TFA.

  4. Estimation of sampling error uncertainties in observed surface air temperature change in China

    NASA Astrophysics Data System (ADS)

    Hua, Wei; Shen, Samuel S. P.; Weithmann, Alexander; Wang, Huijun

    2017-08-01

    This study examines the sampling error uncertainties in the monthly surface air temperature (SAT) change in China over recent decades, focusing on the uncertainties of gridded data, national averages, and linear trends. Results indicate that large sampling error variances appear at the station-sparse area of northern and western China with the maximum value exceeding 2.0 K2 while small sampling error variances are found at the station-dense area of southern and eastern China with most grid values being less than 0.05 K2. In general, the negative temperature existed in each month prior to the 1980s, and a warming in temperature began thereafter, which accelerated in the early and mid-1990s. The increasing trend in the SAT series was observed for each month of the year with the largest temperature increase and highest uncertainty of 0.51 ± 0.29 K (10 year)-1 occurring in February and the weakest trend and smallest uncertainty of 0.13 ± 0.07 K (10 year)-1 in August. The sampling error uncertainties in the national average annual mean SAT series are not sufficiently large to alter the conclusion of the persistent warming in China. In addition, the sampling error uncertainties in the SAT series show a clear variation compared with other uncertainty estimation methods, which is a plausible reason for the inconsistent variations between our estimate and other studies during this period.

  5. Modelled air pollution levels versus EC air quality legislation - results from high resolution simulation.

    PubMed

    Chervenkov, Hristo

    2013-12-01

    An appropriate method for evaluating the air quality of a certain area is to contrast the actual air pollution levels to the critical ones, prescribed in the legislative standards. The application of numerical simulation models for assessing the real air quality status is allowed by the legislation of the European Community (EC). This approach is preferable, especially when the area of interest is relatively big and/or the network of measurement stations is sparse, and the available observational data are scarce, respectively. Such method is very efficient for similar assessment studies due to continuous spatio-temporal coverage of the obtained results. In the study the values of the concentration of the harmful substances sulphur dioxide, (SO2), nitrogen dioxide (NO2), particulate matter - coarse (PM10) and fine (PM2.5) fraction, ozone (O3), carbon monoxide (CO) and ammonia (NH3) in the surface layer obtained from modelling simulations with resolution 10 km on hourly bases are taken to calculate the necessary statistical quantities which are used for comparison with the corresponding critical levels, prescribed in the EC directives. For part of them (PM2.5, CO and NH3) this is done for first time with such resolution. The computational grid covers Bulgaria entirely and some surrounding territories and the calculations are made for every year in the period 1991-2000. The averaged over the whole time slice results can be treated as representative for the air quality situation of the last decade of the former century.

  6. Marine sources of ice nucleating particles: results from phytoplankton cultures and samples collected at sea

    NASA Astrophysics Data System (ADS)

    Wilbourn, E.; Thornton, D.; Brooks, S. D.; Graff, J.

    2016-12-01

    The role of marine aerosols as ice nucleating particles is currently poorly understood. Despite growing interest, there are remarkably few ice nucleation measurements on representative marine samples. Here we present results of heterogeneous ice nucleation from laboratory studies and in-situ air and sea water samples collected during NAAMES (North Atlantic Aerosol and Marine Ecosystems Study). Thalassiosira weissflogii (CCMP 1051) was grown under controlled conditions in batch cultures and the ice nucleating activity depended on the growth phase of the cultures. Immersion freezing temperatures of the lab-grown diatoms were determined daily using a custom ice nucleation apparatus cooled at a set rate. Our results show that the age of the culture had a significant impact on ice nucleation temperature, with samples in stationary phase causing nucleation at -19.9 °C, approximately nine degrees warmer than the freezing temperature during exponential growth phase. Field samples gathered during the NAAMES II cruise in May 2016 were also tested for ice nucleating ability. Two types of samples were gathered. Firstly, whole cells were fractionated by size from surface seawater using a BD Biosciences Influx Cell Sorter (BD BS ISD). Secondly, aerosols were generated using the SeaSweep and subsequently size-selected using a PIXE Cascade Impactor. Samples were tested for the presence of ice nucleating particles (INP) using the technique described above. There were significant differences in the freezing temperature of the different samples; of the three sample types the lab-grown cultures tested during stationary phase froze at the warmest temperatures, followed by the SeaSweep samples (-25.6 °C) and the size-fractionated cell samples (-31.3 °C). Differences in ice nucleation ability may be due to size differences between the INP, differences in chemical composition of the sample, or some combination of these two factors. Results will be presented and atmospheric implications

  7. Soyuz 23 Return Samples: Assessment of Air Quality Aboard the International Space Station

    NASA Technical Reports Server (NTRS)

    James, John T.

    2011-01-01

    Six mini-grab sample containers (m-GSCs) were returned aboard Soyuz 23 because of concerns that new air pollutants had been present in the air and these were getting into the water recovery system. The Total Organic Carbon Analyzer had been giving increasing readings of total organic carbon (TOC) in the potable water, and it was postulated that an increased load into the system was responsible. The TOC began to decline in late October, 2010. The toxicological assessment of 6 m-GSCs from the ISS is shown in Table 1. The recoveries of 13C-acetone, fluorobenzene, and chlorobenzene from the GSCs averaged 73, 82, and 59%, respectively. We are working to understand the sub-optimal recovery of chlorobenzene.

  8. Solid sorbent air sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elskamp, C.J.; Schultz, G.R.

    1986-01-01

    A sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine was developed in order to avoid problems typically encountered in the sampling and analysis of low molecular weight aliphatic amines. Samples are collected with adsorbent tubes containing Amberlite XAD-7 resin coated with the derivatizing reagent, NBD chloride (7-chloro-4-nitrobenzo-2-oxa-1,3-diazole). Analysis is performed by high performance liquid chromatography with the use of a fluorescence and/or UV/visible detector. All four amines can be monitored simultaneously, and neither collection nor storage is affected by humidity. Samples are stable at room temperature for at least two weeks. The methodology has been tested for eachmore » of the four amines at sample loadings equivalent to air concentration ranges of 0.5 to 30 ppm for a sample volume of 10 liters. The method shows promise for determining other airborne primary and secondary low molecular weight aliphatic amines.« less

  9. Simultaneous sampling and analysis of indoor air infested with Cimex lectularius L. (Hemiptera: Cimicidae) by solid phase microextraction, thin film microextraction and needle trap device.

    PubMed

    Eom, In-Yong; Risticevic, Sanja; Pawliszyn, Janusz

    2012-02-24

    Air in a room infested by Cimex lectularius L. (Hemiptera: Cimicidae) was sampled simultaneously by three different sampling devices including solid phase microextraction (SPME) fiber coatings, thin film microextraction (TFME) devices, and needle trap devices (NTDs) and then analyzed by gas chromatography-mass spectrometry (GC-MS). The main focus of this study was to fully characterize indoor air by identifying compounds extracted by three different microextraction formats and, therefore, perform both the device comparison and more complete characterization of C. lectularius pheromone. The NTD technique was capable of extracting both (E)-2-hexenal and (E)-2-octenal, which were previously identified as alarm pheromones of bedbugs, and superior NTD recoveries for these two components allowed reliable identification based on mass spectral library searching and linear temperature programmed retention index (LTPRI) technique. While the use of DVB/CAR/PDMS SPME fiber coatings provided complementary sample fingerprinting and profiling results, TFME sampling devices provided discriminative extraction coverage toward highly volatile analytes. In addition to two alarm pheromones, relative abundances of all other analytes were recorded for all three devices and aligned across all examined samples, namely, highly infested area, less infested area, and control samples which were characterized by different bedbug populations. The results presented in the current study illustrate comprehensive characterization of infested indoor air samples through the use of three different non-invasive SPME formats and identification of novel components comprising C. lectularius pheromone, therefore, promising future alternatives for use of potential synthetic pheromones for detection of infestations. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Breakthrough during air sampling with polyurethane foam: What do PUF 2/PUF 1 ratios mean?

    PubMed

    Bidleman, Terry F; Tysklind, Mats

    2018-02-01

    Frontal chromatography theory is applied to describe movement of gaseous semivolatile organic compounds (SVOCs) through a column of polyurethane foam (PUF). Collected mass fractions (F C ) are predicted for sample volume/breakthrough volume ratios (τ = V S /V B ) up to 6.0 and PUF bed theoretical plate numbers (N) from 2 to 16. The predictions assume constant air concentrations and temperatures. Extension of the calculations is done to relate the collection efficiency of a 2-PUF train (F C1+2 ) to the PUF 2/PUF 1 ratio. F C1+2 exceeds 0.9 for PUF 2/PUF 1 ≤ 0.5 and lengths of PUF commonly used in air samplers. As the PUF 2/PUF 1 ratio approaches unity, confidence in these predictions is limited by the analytical ability to distinguish residues on the two PUFs. Field data should not be arbitrarily discarded because some analytes broke through to the backup PUF trap. The fractional collection efficiencies can be used to estimate air concentrations from quantities retained on the PUF trap when sampling is not quantitative. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Methane mole fraction and δ13C above and below the trade wind inversion at Ascension Island in air sampled by aerial robotics

    NASA Astrophysics Data System (ADS)

    Brownlow, R.; Lowry, D.; Thomas, R. M.; Fisher, R. E.; France, J. L.; Cain, M.; Richardson, T. S.; Greatwood, C.; Freer, J.; Pyle, J. A.; MacKenzie, A. R.; Nisbet, E. G.

    2016-11-01

    Ascension Island is a remote South Atlantic equatorial site, ideal for monitoring tropical background CH4. In September 2014 and July 2015, octocopters were used to collect air samples in Tedlar bags from different heights above and below the well-defined Trade Wind Inversion (TWI), sampling a maximum altitude of 2700 m above mean sea level. Sampling captured both remote air in the marine boundary layer below the TWI and also air masses above the TWI that had been lofted by convective systems in the African tropics. Air above the TWI was characterized by higher CH4, but no distinct shift in δ13C was observed compared to the air below. Back trajectories indicate that lofted CH4 emissions from Southern Hemisphere Africa have bulk δ13CCH4 signatures similar to background, suggesting mixed emissions from wetlands, agriculture, and biomass burning. The campaigns illustrate the usefulness of unmanned aerial system sampling and Ascension's value for atmospheric measurement in an understudied region.

  12. Air and Surface Sampling Method for Assessing Exposures to Quaternary Ammonium Compounds Using Liquid Chromatography Tandem Mass Spectrometry.

    PubMed

    LeBouf, Ryan F; Virji, Mohammed Abbas; Ranpara, Anand; Stefaniak, Aleksandr B

    2017-07-01

    This method was designed for sampling select quaternary ammonium (quat) compounds in air or on surfaces followed by analysis using ultraperformance liquid chromatography tandem mass spectrometry. Target quats were benzethonium chloride, didecyldimethylammonium bromide, benzyldimethyldodecylammonium chloride, benzyldimethyltetradecylammonium chloride, and benzyldimethylhexadecylammonium chloride. For air sampling, polytetrafluoroethylene (PTFE) filters are recommended for 15-min to 24-hour sampling. For surface sampling, Pro-wipe® 880 (PW) media was chosen. Samples were extracted in 60:40 acetonitrile:0.1% formic acid for 1 hour on an orbital shaker. Method detection limits range from 0.3 to 2 ng/ml depending on media and analyte. Matrix effects of media are minimized through the use of multiple reaction monitoring versus selected ion recording. Upper confidence limits on accuracy meet the National Institute for Occupational Safety and Health 25% criterion for PTFE and PW media for all analytes. Using PTFE and PW analyzed with multiple reaction monitoring, the method quantifies levels among the different quats compounds with high precision (<10% relative standard deviation) and low bias (<11%). The method is sensitive enough with very low method detection limits to capture quats on air sampling filters with only a 15-min sample duration with a maximum assessed storage time of 103 days before sample extraction. This method will support future exposure assessment and quantitative epidemiologic studies to explore exposure-response relationships and establish levels of quats exposures associated with adverse health effects. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  13. Evaluation of sequential extraction procedures for soluble and insoluble hexavalent chromium compounds in workplace air samples.

    PubMed

    Ashley, Kevin; Applegate, Gregory T; Marcy, A Dale; Drake, Pamela L; Pierce, Paul A; Carabin, Nathalie; Demange, Martine

    2009-02-01

    Because toxicities may differ for Cr(VI) compounds of varying solubility, some countries and organizations have promulgated different occupational exposure limits (OELs) for soluble and insoluble hexavalent chromium (Cr(VI)) compounds, and analytical methods are needed to determine these species in workplace air samples. To address this need, international standard methods ASTM D6832 and ISO 16740 have been published that describe sequential extraction techniques for soluble and insoluble Cr(VI) in samples collected from occupational settings. However, no published performance data were previously available for these Cr(VI) sequential extraction procedures. In this work, the sequential extraction methods outlined in the relevant international standards were investigated. The procedures tested involved the use of either deionized water or an ammonium sulfate/ammonium hydroxide buffer solution to target soluble Cr(VI) species. This was followed by extraction in a sodium carbonate/sodium hydroxide buffer solution to dissolve insoluble Cr(VI) compounds. Three-step sequential extraction with (1) water, (2) sulfate buffer and (3) carbonate buffer was also investigated. Sequential extractions were carried out on spiked samples of soluble, sparingly soluble and insoluble Cr(VI) compounds, and analyses were then generally carried out by using the diphenylcarbazide method. Similar experiments were performed on paint pigment samples and on airborne particulate filter samples collected from stainless steel welding. Potential interferences from soluble and insoluble Cr(III) compounds, as well as from Fe(II), were investigated. Interferences from Cr(III) species were generally absent, while the presence of Fe(II) resulted in low Cr(VI) recoveries. Two-step sequential extraction of spiked samples with (first) either water or sulfate buffer, and then carbonate buffer, yielded quantitative recoveries of soluble Cr(VI) and insoluble Cr(VI), respectively. Three-step sequential

  14. Statistical Literacy and Sample Survey Results

    ERIC Educational Resources Information Center

    McAlevey, Lynn; Sullivan, Charles

    2010-01-01

    Sample surveys are widely used in the social sciences and business. The news media almost daily quote from them, yet they are widely misused. Using students with prior managerial experience embarking on an MBA course, we show that common sample survey results are misunderstood even by those managers who have previously done a statistics course. In…

  15. Occurrence of commonly used pesticides in personal air samples and their associated health risk among paddy farmers.

    PubMed

    Hamsan, Hazwanee; Ho, Yu Bin; Zaidon, Siti Zulfa; Hashim, Zailina; Saari, Nazamid; Karami, Ali

    2017-12-15

    Tanjung Karang, Selangor, is widely known for its paddy cultivation activity and hosts the third largest paddy field in Malaysia. Pesticides contamination in agriculture fields has become an unavoidable problem, as pesticides are used to increase paddy productivity and reduce plant disease. Human exposure to agrichemicals is common and could results in both acute and chronic health effects, such as acute and chronic neurotoxicity. This study aims to determine the concentrations of commonly used pesticides (azoxystrobin, buprofezin, chlorantraniliprole, difenoconazole, fipronil, imidacloprid, isoprothiolane, pretilachlor, propiconazole, pymetrozine, tebuconazole, tricyclazole, and trifloxystrobin) in personal air samples and their associated health risks among paddy farmers. Eighty-three farmers from Tangjung Karang, Selangor were involved in this study. A solid sorbent tube was attached to the farmer's breathing zone with a clip, and an air pump was fastened to the belt to collect personal air samples. Pesticides collected in the XAD-2 resin were extracted with acetone, centrifuged, concentrated via nitrogen blowdown and reconstituted with 1mL of 3:1 ultrapure water/HPLC-grade methanol solution. The extract was analyzed using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The target compounds were detected with a maximum concentration reaching up to 462.5ngm -3 (fipronil). The hazard quotient (HQ) was less than 1 and the hazard index (HI) value was 3.86×10 -3 , indicating that the risk of pesticides related diseases was not significant. The lifetime cancer risk (LCR) for pymetrozine was at an acceptable level (LCR<10 -6 ) with 4.10×10 -8 . The results reported in this study can be beneficial in terms of risk management within the agricultural community. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Air, hand wipe, and surface wipe sampling for Bisphenol A (BPA) among workers in industries that manufacture and use BPA in the United States.

    PubMed

    Hines, Cynthia J; Jackson, Matthew V; Christianson, Annette L; Clark, John C; Arnold, James E; Pretty, Jack R; Deddens, James A

    2017-11-01

    For decades, bisphenol A (BPA) has been used in making polycarbonate, epoxy, and phenolic resins and certain investment casting waxes, yet published exposure data are lacking for U.S. manufacturing workers. In 2013-2014, BPA air and hand exposures were quantified for 78 workers at six U.S. companies making BPA or BPA-based products. Exposure measures included an inhalable-fraction personal air sample on each of two consecutive work days (n = 146), pre- and end-shift hand wipe samples on the second day (n = 74 each), and surface wipe samples (n = 88). Potential determinants of BPA air and end-shift hand exposures (after natural log transformation) were assessed in univariate and multiple regression mixed models. The geometric mean (GM) BPA air concentration was 4.0 µg/m 3 (maximum 920 µg/m 3 ). The end-shift GM BPA hand level (26 µg/sample) was 10-times higher than the pre-shift level (2.6 µg/sample). BPA air and hand exposures differed significantly by industry and job. BPA air concentrations and end-shift hand levels were highest in the BPA-filled wax manufacturing/reclaim industry (GM Air = 48 µg/m 3 , GM Hand-End = 130 µg/sample) and in the job of working with molten BPA-filled wax (GM Air = 43 µg/m 3 , GM Hand-End = 180 µg/sample), and lowest in the phenolic resins industry (GM Air = 0.85 µg/m 3 , GM Hand-End = 0.43 µg/sample) and in the job of flaking phenolic resins (GM AIR = 0.62 µg/m 3 , GM Hand-End = 0.38 µg/sample). Determinants of increased BPA air concentration were industry, handling BPA containers, spilling BPA, and spending ≥50% of the shift in production areas; increasing age was associated with lower air concentrations. BPA hand exposure determinants were influenced by high values for two workers; for all other workers, tasks involving contact with BPA-containing materials and spending ≥50% of the shift in production areas were associated with increased BPA hand levels. Surface wipe BPA levels were significantly lower in

  17. Characterization and validation of sampling and analytical methods for mycotoxins in workplace air.

    PubMed

    Jargot, Danièle; Melin, Sandrine

    2013-03-01

    Mycotoxins are produced by certain plant or foodstuff moulds under growing, transport or storage conditions. They are toxic for humans and animals, some are carcinogenic. Methods to monitor occupational exposure to seven of the most frequently occurring airborne mycotoxins have been characterized and validated. Experimental aerosols have been generated from naturally contaminated particles for sampler evaluation. Air samples were collected on foam pads, using the CIP 10 personal aerosol sampler with its inhalable health-related aerosol fraction selector. The samples were subsequently solvent extracted from the sampling media, cleaned using immunoaffinity (IA) columns and analyzed by liquid chromatography with fluorescence detection. Ochratoxin A (OTA) or fumonisin and aflatoxin derivatives were detected and quantified. The quantification limits were 0.015 ng m(-3) OTA, 1 ng m(-3) fumonisins or 0.5 pg m(-3) aflatoxins, with a minimum dust concentration level of 1 mg m(-3) and a 4800 L air volume sampling. The methods were successfully applied to field measurements, which confirmed that workers could be exposed when handling contaminated materials. It was observed that airborne particles may be more contaminated than the bulk material itself. The validated methods have measuring ranges fully adapted to the concentrations found in the workplace. Their performance meets the general requirements laid down for chemical agent measurement procedures, with an expanded uncertainty less than 50% for most mycotoxins. The analytical uncertainty, comprised between 14 and 24%, was quite satisfactory given the low mycotoxin amounts, when compared to the food benchmarks. The methods are now user-friendly enough to be adopted for personal workplace sampling. They will later allow for mycotoxin occupational risk assessment, as only very few quantitative data have been available till now.

  18. Simulating and explaining passive air sampling rates for semi-volatile compounds on polyurethane foam passive samplers

    PubMed Central

    Petrich, Nicholas T.; Spak, Scott N.; Carmichael, Gregory R.; Hu, Dingfei; Martinez, Andres; Hornbuckle, Keri C.

    2013-01-01

    Passive air samplers (PAS) including polyurethane foam (PUF) are widely deployed as an inexpensive and practical way to sample semi-volatile pollutants. However, concentration estimates from PAS rely on constant empirical mass transfer rates, which add unquantified uncertainties to concentrations. Here we present a method for modeling hourly sampling rates for semi-volatile compounds from hourly meteorology using first-principle chemistry, physics, and fluid dynamics, calibrated from depuration experiments. This approach quantifies and explains observed effects of meteorology on variability in compound-specific sampling rates and analyte concentrations; simulates nonlinear PUF uptake; and recovers synthetic hourly concentrations at a reference temperature. Sampling rates are evaluated for polychlorinated biphenyl congeners at a network of Harner model samplers in Chicago, Illinois during 2008, finding simulated average sampling rates within analytical uncertainty of those determined from loss of depuration compounds, and confirming quasi-linear uptake. Results indicate hourly, daily and interannual variability in sampling rates, sensitivity to temporal resolution in meteorology, and predictable volatility-based relationships between congeners. We quantify importance of each simulated process to sampling rates and mass transfer and assess uncertainty contributed by advection, molecular diffusion, volatilization, and flow regime within the PAS, finding PAS chamber temperature contributes the greatest variability to total process uncertainty (7.3%). PMID:23837599

  19. Ultimate detectability of volatile organic compounds: how much further can we reduce their ambient air sample volumes for analysis?

    PubMed

    Kim, Yong-Hyun; Kim, Ki-Hyun

    2012-10-02

    To understand the ultimately lowest detection range of volatile organic compounds (VOCs) in air, application of a high sensitivity analytical system was investigated by coupling thermal desorption (TD) technique with gas chromatography (GC) and time-of-flight (TOF) mass spectrometry (MS). The performance of the TD-GC/TOF MS system was evaluated using liquid standards of 19 target VOCs prepared in the range of 35 pg to 2.79 ng per μL. Studies were carried out using both total ion chromatogram (TIC) and extracted ion chromatogram (EIC) mode. EIC mode was used for calibration to reduce background and to improve signal-to-noise. The detectability of 19 target VOCs, if assessed in terms of method detection limit (MDL, per US EPA definition) and limit of detection (LOD), averaged 5.90 pg and 0.122 pg, respectively, with the mean coefficient of correlation (R(2)) of 0.9975. The minimum quantifiable mass of target analytes, when determined using real air samples by the TD-GC/TOF MS, is highly comparable to the detection limits determined experimentally by standard. In fact, volumes for the actual detection of the major aromatic VOCs like benzene, toluene, and xylene (BTX) in ambient air samples were as low as 1.0 mL in the 0.11-2.25 ppb range. It was thus possible to demonstrate that most target compounds including those in low abundance could be reliably quantified at concentrations down to 0.1 ppb at sample volumes of less than 10 mL. The unique sensitivity of this advanced analytical system can ultimately lead to a shift in field sampling strategy with smaller air sample volumes facilitating faster, simpler air sampling (e.g., use of gas syringes rather than the relative complexity of pumps or bags/canisters), with greatly reduced risk of analyte breakthrough and minimal interference, e.g., from atmospheric humidity. The improved detection limits offered by this system can also enhance accuracy and measurement precision.

  20. Ram-air sample collection device for a chemical warfare agent sensor

    DOEpatents

    Megerle, Clifford A.; Adkins, Douglas R.; Frye-Mason, Gregory C.

    2002-01-01

    In a surface acoustic wave sensor mounted within a body, the sensor having a surface acoustic wave array detector and a micro-fabricated sample preconcentrator exposed on a surface of the body, an apparatus for collecting air for the sensor, comprising a housing operatively arranged to mount atop the body, the housing including a multi-stage channel having an inlet and an outlet, the channel having a first stage having a first height and width proximate the inlet, a second stage having a second lower height and width proximate the micro-fabricated sample preconcentrator, a third stage having a still lower third height and width proximate the surface acoustic wave array detector, and a fourth stage having a fourth height and width proximate the outlet, where the fourth height and width are substantially the same as the first height and width.

  1. Assessment of Air Quality in the Shuttle and International Space Station (ISS) Based on Samples Returned by STS-104 at the Conclusion of 7A

    NASA Technical Reports Server (NTRS)

    James, John T.

    2001-01-01

    The toxicological assessment of air samples returned at the end of the STS-l04 (7 A) flight to the ISS is reported. ISS air samples were taken in June and July 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges. Preflight and end-of-mission samples were obtained from Atlantis using GSCs. Solid sorbent air sampler (SSAS) samples were obtained from the ISS in April, June, and July. Analytical methods have not changed from earlier reports, and all quality control measures were met.

  2. STATISTICAL ANALYSIS OF TANK 19F FLOOR SAMPLE RESULTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris, S.

    2010-09-02

    Representative sampling has been completed for characterization of the residual material on the floor of Tank 19F as per the statistical sampling plan developed by Harris and Shine. Samples from eight locations have been obtained from the tank floor and two of the samples were archived as a contingency. Six samples, referred to in this report as the current scrape samples, have been submitted to and analyzed by SRNL. This report contains the statistical analysis of the floor sample analytical results to determine if further data are needed to reduce uncertainty. Included are comparisons with the prior Mantis samples resultsmore » to determine if they can be pooled with the current scrape samples to estimate the upper 95% confidence limits (UCL95%) for concentration. Statistical analysis revealed that the Mantis and current scrape sample results are not compatible. Therefore, the Mantis sample results were not used to support the quantification of analytes in the residual material. Significant spatial variability among the current scrape sample results was not found. Constituent concentrations were similar between the North and South hemispheres as well as between the inner and outer regions of the tank floor. The current scrape sample results from all six samples fall within their 3-sigma limits. In view of the results from numerous statistical tests, the data were pooled from all six current scrape samples. As such, an adequate sample size was provided for quantification of the residual material on the floor of Tank 19F. The uncertainty is quantified in this report by an UCL95% on each analyte concentration. The uncertainty in analyte concentration was calculated as a function of the number of samples, the average, and the standard deviation of the analytical results. The UCL95% was based entirely on the six current scrape sample results (each averaged across three analytical determinations).« less

  3. Integrated sampling and analysis unit for the determination of sexual pheromones in environmental air using fabric phase sorptive extraction and headspace-gas chromatography-mass spectrometry.

    PubMed

    Alcudia-León, M Carmen; Lucena, Rafael; Cárdenas, Soledad; Valcárcel, Miguel; Kabir, Abuzar; Furton, Kenneth G

    2017-03-10

    This article presents a novel unit that integrates for the first time air sampling and preconcentration based on the use of fabric phase sorptive extraction principles. The determination of Tuta absoluta sexual pheromone traces in environmental air has been selected as analytical problem. For this aim, a novel laboratory-built unit made up of commercial brass elements as holder of the sol-gel coated fabric extracting phase has been designed and optimized. The performance of the integrated unit was evaluated analyzing environmental air sampled in tomato crops. The unit can work under sampling and analysis mode which eliminates any need for sorptive phase manipulation prior to instrumental analysis. In the sampling mode, the unit can be connected to a sampling pump to pass the air through the sorptive phase at a controlled flow-rate. In the analysis mode, it is placed in the gas chromatograph autosampler without any instrumental modification. It also diminishes the risk of cross contamination between sampling and analysis. The performance of the new unit has been evaluated using the main components of the sexual pheromone of Tuta absoluta [(3E,8Z,11Z)-tetradecatrien-1-yl acetate and (3E,8Z)-tetradecadien-1-yl acetate] as model analytes. The limits of detection for both compounds resulted to be 1.6μg and 0.8μg, respectively, while the precision (expressed as relative standard deviation) was better than 3.7%. Finally, the unit has been deployed in the field to analyze a number of real life samples, some of them were found positive. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. 24-HOUR DIFFUSIVE SAMPLING OF TOXIC VOCS IN AIR ONTO CARBOPACK X SOLID ADSORBENT FOLLOWED BY THERMAL DESORPTION/GC/MS ANALYSIS - LABORATORY STUDIES

    EPA Science Inventory

    Diffusive sampling of a mixture of 42 volatile organic compounds (VOCs) in humidified, purified air onto the solid adsorbent Carbopack X was evaluated under controlled laboratory conditions. The evaluation included variations in sample air temperature, relative humidity, and ozon...

  5. STS 134, 135 and 26S Return Samples: Air Quality aboard Shuttle (STS-134) and International Space Station

    NASA Technical Reports Server (NTRS)

    James, John T.

    2011-01-01

    This is a very limited set of samples on which to perform an air quality assessment. However, based on these samples, we have no reason to believe that nominal ISS air is unsafe to breathe. We must continue to be vigilant when dealing with nominal atmospheres in ISS. New, unmanned modules require special attention when the crew first enters. Carbon Monoxide Accumulation aboard ISS: Beginning in late 2008 the nominal concentrations of CO began increasing gradually (Figure 1). The results from samples returned on this flight indicate that the CO concentrations, after dropping in late 2009, have cycled upward and then settled back to concentrations near 2 mg/m3. In any case, these changes are well below the 180-day SMAC for CO, which is17 mg/m3. There is no threat to crew health. Carbon Dioxide: This anthropogenic compound has drawn much attention recently because of the possibility that it could contribute to the effects of intracranial hypertension experienced because of spaceflight-induced fluid shifts. From now on we will maintain a plot (Figure 2) of carbon dioxide concentrations ( SD) by averaging the values found in the 3-5 mini-GSC samples taken each month in diverse locations of the ISS. This will enable us to estimate the average exposure of crewmembers to carbon dioxide during their stay aboard the ISS. In general, concentrations are being maintained below 3.5 mmHg. Figure 1

  6. SAMPLE DESIGN CONSIDERATIONS FOR INDOOR AIR EXPOSURE SURVEYS

    EPA Science Inventory

    Recent studies have shown that the traditional practice of monitoring outdoor (ambient) air quality leads to little information regarding the exposures of people in indoor surroundings. Consequently, EPA has begun a series of studies to determine the air pollution exposures peopl...

  7. Development of one-step hollow fiber supported liquid phase sampling technique for occupational workplace air analysis using high performance liquid chromatography with ultra-violet detector.

    PubMed

    Yan, Cheing-Tong; Chien, Hai-Ying

    2012-07-13

    In this study, a simple and novel one-step hollow-fiber supported liquid-phase sampling (HF-LPS) technique was developed for enriched sampling of gaseous toxic species prior to chemical analysis for workplace air monitoring. A lab-made apparatus designed with a gaseous sample generator and a microdialysis sampling cavity (for HF-LPS) was utilized and evaluated to simulate gaseous contaminant air for occupational workplace analysis. Gaseous phenol was selected as the model toxic species. A polyethersulfone hollow fiber dialysis module filled with ethylene glycol in the shell-side was applied as the absorption solvent to collect phenol from a gas flow through the tube-side, based on the concentration distribution of phenol between the absorption solvent and the gas flow. After sampling, 20 μL of the extractant was analyzed by high performance liquid chromatography with ultraviolet detection (HPLC-UV). Factors that influence the generation of gaseous standards and the HF-LPS were studied thoroughly. Results indicated that at 25 °C the phenol (2000 μg/mL) standard solution injected at 15-μL/min can be vaporized into sampling cavity under nitrogen flow at 780 mL/min, to generate gaseous phenol with concentration approximate to twice the permissible exposure limit. Sampling at 37.3 mL/min for 30 min can meet the requirement of the workplace air monitoring. The phenol in air ranged between 0.7 and 10 cm³/m³ (shows excellent linearity) with recovery between 98.1 and 104.1%. The proposed method was identified as a one-step sampling for workplace monitoring with advantages of convenience, rapidity, sensitivity, and usage of less-toxic solvent. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Comparison of Lichen, Conifer Needles, Passive Air Sampling Devices, and Snowpack as Passive Sampling Media to Measure Semi-Volatile Organic Compounds in Remote Atmospheres

    PubMed Central

    SCHRLAU, JILL E.; GEISER, LINDA; HAGEMAN, KIMBERLY J.; LANDERS, DIXON H.

    2011-01-01

    A wide range of semi-volatile organic compounds (SOCs), including pesticides and polycyclic aromatic hydrocarbons (PAHs), were measured in lichen, conifer needles, snowpack and XAD-based passive air sampling devices (PASDs) collected from 19 different U.S. national parks in order to compare the magnitude and mechanism of SOC accumulation in the different passive sampling media. Lichen accumulated the highest SOC concentrations, in part because of its long (and unknown) exposure period, while PASDs accumulated the lowest concentrations. However, only the PASD SOC concentrations can be used to calculate an average atmospheric gas-phase SOC concentration because the sampling rates are known and the media is uniform. Only the lichen and snowpack SOC accumulation profiles were statistically significantly correlated (r = 0.552, p-value <0.0001) because they both accumulate SOCs present in the atmospheric particle-phase. This suggests that needles and PASDs represent a different composition of the atmosphere than lichen and snowpack and that the interpretation of atmospheric SOC composition is dependent on the type of passive sampling media used. All four passive sampling media preferentially accumulated SOCs with relatively low air-water partition coefficients, while snowpack accumulated SOCs with higher log KOA values compared to the other media. Lichen accumulated more SOCs with log KOA > 10 relative to needles and showed a greater accumulation of particle-phase PAHs. PMID:22087860

  9. STATISTICAL ANALYSIS OF TANK 18F FLOOR SAMPLE RESULTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris, S.

    2010-09-02

    Representative sampling has been completed for characterization of the residual material on the floor of Tank 18F as per the statistical sampling plan developed by Shine [1]. Samples from eight locations have been obtained from the tank floor and two of the samples were archived as a contingency. Six samples, referred to in this report as the current scrape samples, have been submitted to and analyzed by SRNL [2]. This report contains the statistical analysis of the floor sample analytical results to determine if further data are needed to reduce uncertainty. Included are comparisons with the prior Mantis samples resultsmore » [3] to determine if they can be pooled with the current scrape samples to estimate the upper 95% confidence limits (UCL{sub 95%}) for concentration. Statistical analysis revealed that the Mantis and current scrape sample results are not compatible. Therefore, the Mantis sample results were not used to support the quantification of analytes in the residual material. Significant spatial variability among the current sample results was not found. Constituent concentrations were similar between the North and South hemispheres as well as between the inner and outer regions of the tank floor. The current scrape sample results from all six samples fall within their 3-sigma limits. In view of the results from numerous statistical tests, the data were pooled from all six current scrape samples. As such, an adequate sample size was provided for quantification of the residual material on the floor of Tank 18F. The uncertainty is quantified in this report by an upper 95% confidence limit (UCL{sub 95%}) on each analyte concentration. The uncertainty in analyte concentration was calculated as a function of the number of samples, the average, and the standard deviation of the analytical results. The UCL{sub 95%} was based entirely on the six current scrape sample results (each averaged across three analytical determinations).« less

  10. A system for high-quality CO2 isotope analyses of air samples collected by the CARIBIC Airbus A340-600.

    PubMed

    Assonov, S; Taylor, P; Brenninkmeijer, C A M

    2009-05-01

    delta18O(CO2) on the VPDB-CO2 scale, estimated on runs of CO2-air mixtures, is +/-0.040 per thousand and 0.060 per thousand (2-sigma values). Inter-comparison with MPI-BGC resulted in a scale discrepancy of a similar magnitude. Although the reason(s) for this discrepancy still need to be understood, this basically confirms the approach of using specifically prepared CO2-air mixtures as a calibration carrier, in order to achieve scale unification among laboratories. As important practical application and as a critical test, JRC-IRMM took part in the passenger aircraft-based global monitoring project CARIBIC (http://www.caribic-atmospheric.com). In this way, reliable CO2 isotope data for the tropopause region and the free troposphere were obtained. From June 2007 to January 2009, approximately 500 CARIBIC air samples have been analysed. Some flights demonstrated a compact correlation of both delta13C(CO2) and delta18O(CO2) with respect to CO2 concentration, demonstrating mixing of tropospheric and stratospheric air masses. These excellent correlations provide an independent, realistic data quality check. Copyright (c) 2009 John Wiley & Sons, Ltd.

  11. US EPA Base Study Standard Operating Procedure for Sampling and Characterization of Viable and Non-Viable Bioaerosols in Indoor Air

    EPA Pesticide Factsheets

    The objective of the procedure is to collect a representative sample concentration of total airborne fungal spores (viable and non-viable) that may be present in indoor air and in the outdoor air supplied to the space tested.

  12. Study of the ambient air metallic elements Cr, Cu, Zn, Cd and Pb at HAF sampling sites.

    PubMed

    Fang, Guor-Cheng; Kuo, Yu-Chen; Zhuang, Yuan-Jie; Tsai, Kai-Hsiang; Huang, Wen-Chuan

    2017-08-01

    This study characterized diurnal variations in the compositions of total suspended particulates (TSP) and dry deposits of particulates from ambient air, and the metallic elements that are contained in them at harbor, airport and farmland (HAF) sampling sites from August, 2013 to July, 2014. Two-way ANOVA of the amounts of metallic elements in the TSP and dry deposits was carried out in all four seasons at the HAF sampling sites. The metallic elements Cr and Cu originated in local emission sources at the airport. Metallic elements Zn and Pb originated in local emission sources at the harbor. Finally, metallic element Cd originated in local emissions form farmland. The following results were also obtained. (1) The metallic composition of the TSP differed significantly from that of the dry deposits in all four seasons at the harbor and farmland sampling sites, but not at the airport sampling site. (2) High correlations coefficients were found between the amounts of metallic elements Cr and Cu in the TSP and those in the dry deposits at the airport sampling site. (3) Pb was present in the TSP and the dry deposits at the harbor sampling site.

  13. Development of sampling and analytical methods for concerted determination of commonly used chloroacetanilide, chlorotriazine, and 2,4-D herbicides in hand-wash, dermal-patch, and air samples.

    PubMed

    Tucker, S P; Reynolds, J M; Wickman, D C; Hines, C J; Perkins, J B

    2001-06-01

    Sampling and analytical methods were developed for commonly used chloroacetanilide, chlorotriazine, and 2,4-D herbicides in hand washes, on dermal patches, and in air. Eight herbicides selected for study were alachlor, atrazine, cyanazine, 2,4-dichlorophenoxyacetic acid (2,4-D), metolachlor, simazine, and two esters of 2,4-D, the 2-butoxyethyl ester (2,4-D, BE) and the 2-ethylhexyl ester (2,4-D, EH). The hand-wash method consisted of shaking the worker's hand in 150 mL of isopropanol in a polyethylene bag for 30 seconds. The dermal-patch method entailed attaching a 10-cm x 10-cm x 0.6-cm polyurethane foam (PUF) patch to the worker for exposure; recovery of the herbicides was achieved by extraction with 40 mL of isopropanol. The air method involved sampling with an OVS-2 tube (which contained an 11-mm quartz fiber filter and two beds of XAD-2 resin) and recovery with 2 mL of 10:90 methanol:methyl t-butyl ether. Analysis of each of the three sample types was performed by gas chromatography with an electron-capture detector. Diazomethane in solution was employed to convert 2,4-D as the free acid to the methyl ester in each of the three methods for ease of gas chromatography. Silicic acid was added to sample solutions to quench excess diazomethane. Limits of detection for all eight herbicides were matrix-dependent and, generally, less than 1 microgram per sample for each matrix. Sampling and analytical methods met NIOSH evaluation criteria for all herbicides in hand-wash samples, for seven herbicides in air samples (all herbicides except cyanazine), and for six herbicides in dermal-patch samples (all herbicides except cyanazine and 2,4-D). Speciation of 2,4-D esters and simultaneous determination of 2,4-D acid were possible without losses of the esters or of other herbicides (acetanilides and triazines) being determined.

  14. Venturi Air-Jet Vacuum Ejector For Sampling Air

    NASA Technical Reports Server (NTRS)

    Hill, Gerald F.; Sachse, Glen W.; Burney, L. Garland; Wade, Larry O.

    1990-01-01

    Venturi air-jet vacuum ejector pump light in weight, requires no electrical power, does not contribute heat to aircraft, and provides high pumping speeds at moderate suctions. High-pressure motive gas required for this type of pump bled from compressor of aircraft engine with negligible effect on performance of engine. Used as source of vacuum for differential-absorption CO-measurement (DACOM), modified to achieve in situ measurements of CO at frequency response of 10 Hz. Provides improvement in spatial resolution and potentially leads to capability to measure turbulent flux of CO by use of eddy-correlation technique.

  15. Eclipse Science Results from the Airborne Infrared Spectrometer (AIR-Spec)

    NASA Astrophysics Data System (ADS)

    Samra, J.; Cheimets, P.; DeLuca, E.; Golub, L.; Judge, P. G.; Lussier, L.; Madsen, C. A.; Marquez, V.; Tomczyk, S.; Vira, A.

    2017-12-01

    We present the first science results from the commissioning flight of the Airborne Infrared Spectrometer (AIR-Spec), an innovative solar spectrometer that will observe the 2017 solar eclipse from the NSF/NCAR High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER). During the eclipse, AIR-Spec will image five magnetically sensitive coronal emission lines between 1.4 and 4 microns to determine whether they may be useful probes of coronal magnetism. The instrument will measure emission line intensity, FWHM, and Doppler shift from an altitude of over 14 km, above local weather and most of the absorbing water vapor. Instrumentation includes an image stabilization system, feed telescope, grating spectrometer, infrared camera, and visible slit-jaw imager. Results from the 2017 eclipse are presented in the context of the mission's science goals. AIR-Spec will identify line strengths as a function of position in the solar corona and search for the high frequency waves that are candidates for heating and acceleration of the solar wind. The instrument will also identify large scale flows in the corona, particularly in polar coronal holes. Three of the five lines are expected to be strong in coronal hole plasmas because they are excited in part by scattered photospheric light. Line profile analysis will probe the origins of the fast and slow solar wind. Finally, the AIR-Spec measurements will complement ground based eclipse observations to provide detailed plasma diagnostics throughout the corona. AIR-Spec will measure infrared emission of ions observed in the visible from the ground, giving insight into plasma heating and acceleration at radial distances inaccessible to existing or planned spectrometers.

  16. An Improved Extraction and Analysis Technique for Determination of Carbon Monoxide Stable Isotopes and Mixing Ratios from Ice Core and Atmospheric Air Samples.

    NASA Astrophysics Data System (ADS)

    Place, P., Jr.; Petrenko, V. V.; Vimont, I.

    2017-12-01

    Carbon Monoxide (CO) is an important atmospheric trace gas that affects the oxidative capacity of the atmosphere and contributes indirectly to anthropogenic radiative forcing. Carbon monoxide stable isotopes can also serve as a tracer for variations in biomass burning, particularly in the preindustrial atmosphere. A good understanding of the past variations in CO mole fractions and isotopic composition can help improve the skill of chemical transport models and constrain biomass burning changes. Ice cores may preserve a record of past atmospheric CO for analysis and interpretation. To this end, a new extraction system has been developed for analysis of stable isotopes (δ13CO and δC18O) of atmospheric carbon monoxide from ice core and atmospheric air samples. This system has been designed to measure relatively small sample sizes (80 cc STP of air) to accommodate the limited availability of ice core samples. Trapped air is extracted from ice core samples via melting in a glass vacuum chamber. This air is expanded into a glass expansion loop and then compressed into the sample loop of a Reducing Gas Detector (Peak Laboratories, Peak Performer 1 RCP) for the CO mole fraction measurement. The remaining sample gas will be expelled from the melt vessel into a larger expansion loop via headspace compression for isotopic analysis. The headspace compression will be accomplished by introduction of clean degassed water into the bottom of the melt vessel. Isotopic analysis of the sample gas is done utilizing the Schütze Reagent to convert the carbon monoxide to carbon dioxide (CO2) which is then measured using continuous-flow isotope ratio mass spectrometry (Elementar Americas, IsoPrime 100). A series of cryogenic traps are used to purify the sample air, capture the converted sample CO2, and cryofocus the sample CO2 prior to injection.

  17. NEW APPLICATION OF PASSIVE SAMPLING DEVICES FOR ASSESSMENT OF RESPIRATORY EXPOSURE TO PESTICIDES IN INDOOR AIR

    EPA Science Inventory

    The United States Environmental Protection Agency (EPA) has long maintained an interest in potential applications of passive sampling devices (PSDs) for estimating the concentrations of various pollutants in air. Typically PSDs were designed for the workplace monitoring of vola...

  18. Results of the air emission research study

    USDA-ARS?s Scientific Manuscript database

    Air quality was monitored in beef mono-slope barns. The objectives of the study were 1) to gather baseline data for the levels of gas emissions and particulate matter from beef mono-slope facilities, 2) evaluate the effect of two different manure handling systems on air quality, and 3) provide infor...

  19. [Determination of short-chain chlorinated paraffins in ambient air using high-volume sampling combined with high resolutimi gas chromatography-electron capture negative ion-low resolution mass spectrometry].

    PubMed

    Shi, Loimeng; Gao, Yuan; Hou, Xiaohong; Zhang, Haijun; Zhang, Yichi; Chen, Jiping

    2016-02-01

    An analytical method for quantifying short-chain chlorinated paraffins (SCCPs) in ambient air using high-volume sampling combined with high resolution gas chromatography-electron capture negative ion-low resolution mass spectrometry ( HRGC-ECNI-LRMS) was developed. An acidified silica gel column and a basic alumina column were used to optimize the cleanup procedures. The results showed a good linearity (R2>0. 99) between the total response factors and the degree of chlorination of SCCPs in the content range of 58. 1%-63. 3%. The limits of detection (S/N ≥3) and the limits of quantification (S/N ≥ 10) were 4. 2 and 12 µg, respectively. The method detection limit (MDL) for SCCPs was 0. 34 ng/m3 (n = 7). The recoveries of SCCPs in air samples were in the range of 81. 9% to 94. 2%. It is demonstrated that the method is suitable for the quantitative analysis of SCCPs in air samples.

  20. Determination of biomass burning tracers in air samples by GC/MS

    NASA Astrophysics Data System (ADS)

    Janoszka, Katarzyna

    2018-01-01

    Levoglucosan (LG) as a main cellulose burning product at 300°C is a biomass burning tracer. LG characterize by relatively high molar mass and it is sorbed by particulate matter. In the study of air pollution monitoring LG is mainly analyzed in particulate matter, PM1 and PM2,5. The tracer create relatively high O-H…O bond and weaker C-H…O bond. Due to the hydrogen bond, LG dissolves very well in water. Analytical procedure of LG determination include: extraction, derivatization and analysis by gas chromatography coupled with mass spectrometry detector. In water samples levoglucosan is determined by liquid chromatography. The paper presents a methodology for particulate matter samples determination their analysis by gas chromatography coupled with a mass spectrometry detector. Determination of LG content in particulate matter was performed according to an analytical method based on simultaneous pyridine extraction and derivatization using N,O-bis (trimethylsilyl) trifluoroacetamide and trimethylchlorosilane mixture (BSTFA: TMCS, 99: 1).

  1. Automated air-void system characterization of hardened concrete: Helping computers to count air-voids like people count air-voids---Methods for flatbed scanner calibration

    NASA Astrophysics Data System (ADS)

    Peterson, Karl

    Since the discovery in the late 1930s that air entrainment can improve the durability of concrete, it has been important for people to know the quantity, spacial distribution, and size distribution of the air-voids in their concrete mixes in order to ensure a durable final product. The task of air-void system characterization has fallen on the microscopist, who, according to a standard test method laid forth by the American Society of Testing and Materials, must meticulously count or measure about a thousand air-voids per sample as exposed on a cut and polished cross-section of concrete. The equipment used to perform this task has traditionally included a stereomicroscope, a mechanical stage, and a tally counter. Over the past 30 years, with the availability of computers and digital imaging, automated methods have been introduced to perform the same task, but using the same basic equipment. The method described here replaces the microscope and mechanical stage with an ordinary flatbed desktop scanner, and replaces the microscopist and tally counter with a personal computer; two pieces of equipment much more readily available than a microscope with a mechanical stage, and certainly easier to find than a person willing to sit for extended periods of time counting air-voids. Most laboratories that perform air-void system characterization typically have cabinets full of prepared samples with corresponding results from manual operators. Proponents of automated methods often take advantage of this fact by analyzing the same samples and comparing the results. A similar iterative approach is described here where scanned images collected from a significant number of samples are analyzed, the results compared to those of the manual operator, and the settings optimized to best approximate the results of the manual operator. The results of this calibration procedure are compared to an alternative calibration procedure based on the more rigorous digital image accuracy

  2. Stratospheric Trace Gas Composition Studies Utilizing in situ Cryogenic, Whole-Air Sampling Methods.

    DTIC Science & Technology

    1981-03-10

    C A FORSBERG, R V PIERI UNCLASSIFIED AFGL-TR-81-0071 NLEEEE..EEEEEEllllllu *Inaggol/numln ElhElhEEEEEEEI lllllllhhl , O \\ Stratospheric Trace Gas...GRANT NUJMBERr4; Charles A. Forsberg Robert V. Pieri , Capt., USAF Gerard A. Faucher B PERFORMING ORGANIZATION NAME AND ADDRESS IS. PROGRAM ELEMENT...launch site. 1 (Received for publication 10 March 1981) 1. Gallagher, C.(C., and Pieri , R. V. (1976) Cryogenic, Whole-Air Sampl1r and Program for

  3. Isokinetic air sampler

    DOEpatents

    Sehmel, George A.

    1979-01-01

    An isokinetic air sampler includes a filter, a holder for the filter, an air pump for drawing air through the filter at a fixed, predetermined rate, an inlet assembly for the sampler having an inlet opening therein of a size such that isokinetic air sampling is obtained at a particular wind speed, a closure for the inlet opening and means for simultaneously opening the closure and turning on the air pump when the wind speed is such that isokinetic air sampling is obtained. A system incorporating a plurality of such samplers provided with air pumps set to draw air through the filter at the same fixed, predetermined rate and having different inlet opening sizes for use at different wind speeds is included within the ambit of the present invention as is a method of sampling air to measure airborne concentrations of particulate pollutants as a function of wind speed.

  4. Statistical literacy and sample survey results

    NASA Astrophysics Data System (ADS)

    McAlevey, Lynn; Sullivan, Charles

    2010-10-01

    Sample surveys are widely used in the social sciences and business. The news media almost daily quote from them, yet they are widely misused. Using students with prior managerial experience embarking on an MBA course, we show that common sample survey results are misunderstood even by those managers who have previously done a statistics course. In general, they fare no better than managers who have never studied statistics. There are implications for teaching, especially in business schools, as well as for consulting.

  5. Results from CrIS/ATMS Obtained Using an AIRS "Version-6 Like" Retrieval Algorithm

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Kouvaris, Louis; Iredell, Lena

    2015-01-01

    We have tested and evaluated Version-6.22 AIRS and Version-6.22 CrIS products on a single day, December 4, 2013, and compared results to those derived using AIRS Version-6. AIRS and CrIS Version-6.22 O3(p) and q(p) products are both superior to those of AIRS Version-6All AIRS and CrIS products agree reasonably well with each other CrIS Version-6.22 T(p) and q(p) results are slightly poorer than AIRS under very cloudy conditions. Both AIRS and CrIS Version-6.22 run now at JPL. Our short term plans are to analyze many common months at JPL in the near future using Version-6.22 or a further improved algorithm to assess the compatibility of AIRS and CrIS monthly mean products and their interannual differencesUpdates to the calibration of both CrIS and ATMS are still being finalized. JPL plans, in collaboration with the Goddard DISC, to reprocess all AIRS data using a still to be finalized Version-7 retrieval algorithm, and to reprocess all recalibrated CrISATMS data using Version-7 as well.

  6. Results from CrIS/ATMS Obtained Using an AIRS "Version-6 like" Retrieval Algorithm

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Kouvaris, Louis; Iredell, Lena

    2015-01-01

    We tested and evaluated Version-6.22 AIRS and Version-6.22 CrIS products on a single day, December 4, 2013, and compared results to those derived using AIRS Version-6. AIRS and CrIS Version-6.22 O3(p) and q(p) products are both superior to those of AIRS Version-6All AIRS and CrIS products agree reasonably well with each other. CrIS Version-6.22 T(p) and q(p) results are slightly poorer than AIRS over land, especially under very cloudy conditions. Both AIRS and CrIS Version-6.22 run now at JPL. Our short term plans are to analyze many common months at JPL in the near future using Version-6.22 or a further improved algorithm to assess the compatibility of AIRS and CrIS monthly mean products and their interannual differences. Updates to the calibration of both CrIS and ATMS are still being finalized. JPL plans, in collaboration with the Goddard DISC, to reprocess all AIRS data using a still to be finalized Version-7 retrieval algorithm, and to reprocess all recalibrated CrISATMS data using Version-7 as well.

  7. On the construction, comparison, and variability of airsheds for interpreting semivolatile organic compounds in passively sampled air.

    PubMed

    Westgate, John N; Wania, Frank

    2011-10-15

    Air mass origin as determined by back trajectories often aids in explaining some of the short-term variability in the atmospheric concentrations of semivolatile organic contaminants. Airsheds, constructed by amalgamating large numbers of back trajectories, capture average air mass origins over longer time periods and thus have found use in interpreting air concentrations obtained by passive air samplers. To explore some of their key characteristics, airsheds for 54 locations on Earth were constructed and compared for roundness, seasonality, and interannual variability. To avoid the so-called "pole problem" and to simplify the calculation of roundness, a "geodesic grid" was used to bin the back-trajectory end points. Departures from roundness were seen to occur at all latitudes and to correlate significantly with local slope but no strong relationship between latitude and roundness was revealed. Seasonality and interannual variability vary widely enough to imply that static models of transport are not sufficient to describe the proximity of an area to potential sources of contaminants. For interpreting an air measurement an airshed should be generated specifically for the deployment time of the sampler, especially when investigating long-term trends. Samples taken in a single season may not represent the average annual atmosphere, and samples taken in linear, as opposed to round, airsheds may not represent the average atmosphere in the area. Simple methods are proposed to ascertain the significance of an airshed or individual cell. It is recommended that when establishing potential contaminant source regions only end points with departure heights of less than ∼700 m be considered.

  8. Passive air sampling using semipermeable membrane devices at different wind-speeds in situ calibrated by performance reference compounds.

    PubMed

    Söderström, Hanna S; Bergqvist, Per-Anders

    2004-09-15

    Semipermeable membrane devices (SPMDs) are passive samplers used to measure the vapor phase of organic pollutants in air. This study tested whether extremely high wind-speeds during a 21-day sampling increased the sampling rates of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), and whether the release of performance reference compounds (PRCs) was related to the uptakes at different wind-speeds. Five samplers were deployed in an indoor, unheated, and dark wind tunnel with different wind-speeds at each site (6-50 m s(-1)). In addition, one sampler was deployed outside the wind tunnel and one outside the building. To test whether a sampler, designed to reduce the wind-speeds, decreased the uptake and release rates, each sampler in the wind tunnel included two SPMDs positioned inside a protective device and one unprotected SPMD outside the device. The highest amounts of PAHs and PCBs were found in the SPMDs exposed to the assumed highest wind-speeds. Thus, the SPMD sampling rates increased with increasing wind-speeds, indicating that the uptake was largely controlled by the boundary layer at the membrane-air interface. The coefficient of variance (introduced by the 21-day sampling and the chemical analysis) for the air concentrations of three PAHs and three PCBs, calculated using the PRC data, was 28-46%. Thus, the PRCs had a high ability to predict site effects of wind and assess the actual sampling situation. Comparison between protected and unprotected SPMDs showed that the sampler design reduced the wind-speed inside the devices and thereby the uptake and release rates.

  9. BIBLE A whole-air sampling as a window on Asian biogeochemistry

    NASA Astrophysics Data System (ADS)

    Elliott, Scott; Blake, Donald R.; Blake, Nicola J.; Dubey, Manvendra K.; Rowland, F. Sherwood; Sive, Barkley C.; Smith, Felisa A.

    2003-02-01

    Asian trace gas and aerosol emissions into carbon, nitrogen, and other elemental cycles will figure prominently in near term Earth system evolution. Atmospheric hydrocarbon measurements resolve numerous chemical species and can be used to investigate sourcing for key geocarriers. A recent aircraft study of biomass burning and lightning (BIBLE A) explored the East Asian atmosphere and was unique in centering on the Indonesian archipelago. Samples of volatile organics taken over/between the islands of Japan, Saipan, Java, and Borneo are here examined as a guide to whole-air-based studies of future Asian biogeochemistry. The midlatitude onshore/offshore pulse and tropical convection strongly influence concentration distributions. As species of increasing molecular weight are considered, rural, combustion, and industrial source regimes emerge. Methane-rich inputs such as waste treatment and rice cultivation are evidenced in the geostrophic outflow. The Indonesian atmosphere is rich in biomass burning markers and also those of vehicular activity. Complexity of air chemistry in the archipelago is a direct reflection of diverse topography, land use, and local economies in a rapidly developing nation. Conspicuous in its absence is the fingerprint for liquefied petroleum gas leakage, but it can be expected to appear as demand for clean fossil fuels rises along with per capita incomes. Combustion tracers indicate high nitrogen mobilization rates, linking regional terrestrial geocycles with open marine ecosystems. Sea to air fluxes are superimposed on continental and marine backgrounds for the methyl halides. However, ocean hot spots are not coordinated and suggest an intricate subsurface kinetics. Levels of long-lived anthropogenic halocarbons attest to the success of international environmental treaties while reactive chlorine containing species track industrial air masses. The dozens of hydrocarbons resolvable by gas chromatographic methods will enable monitoring of

  10. Comparison of arterial and venous blood gases and the effects of analysis delay and air contamination on arterial samples in patients with chronic obstructive pulmonary disease and healthy controls.

    PubMed

    O'Connor, T M; Barry, P J; Jahangir, A; Finn, C; Buckley, B M; El-Gammal, A

    2011-01-01

    Arterial blood gases (ABGs) are often sampled incorrectly, leading to a 'mixed' or venous sample. Delays in analysis and air contamination are common. We measured the effects of these errors in patients with chronic obstructive pulmonary disease (COPD) exacerbations and controls. Arterial and venous samples were analyzed from 30 patients with COPD exacerbation and 30 controls. Venous samples were analysed immediately and arterial samples separated into non-air-contaminated and air-contaminated specimens and analysed at 0, 30, 60, 90 and 180 min. Mean venous pH was 7.371 and arterial pH was 7.407 (p < 0.0001). There was a correlation between venous and arterial pH (r = 0.5347, p < 0.0001). The regression equation to predict arterial pH was: arterial pH = 4.2289 + 0.43113 · venous pH. There were no clinically significant differences in arterial PO₂ associated with analysis delay. A statistically significant decline in pH was detected at 30 min in patients with COPD exacerbation (p = 0.0042) and 90 min in controls (p < 0.0001). A clinically significant decline in pH emerged at 73 min in patients with COPD exacerbation and 87 min in controls. Air contamination was associated with a clinically significant increase in PO₂ in all samples, including those that were immediately analyzed. Arterial and venous pH differ significantly. Venous pH cannot accurately replace arterial pH. Temporal delays in ABG analysis result in a significant decline in measured pH. ABGs should be analysed within 30 min. Air contamination leads to an immediate increase in measured PO₂, indicating that air-contaminated ABGs should be discarded. Copyright © 2010 S. Karger AG, Basel.

  11. Radiological results for samples collected on paired glass- and cellulose-fiber filters at the Sandia complex, Tonopah Test Range, Nevada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mizell, Steve A.; Shadel, Craig A.

    Airborne particulates are collected at U.S. Department of Energy sites that exhibit radiological contamination on the soil surface to help assess the potential for wind to transport radionuclides from the contamination sites. Collecting these samples was originally accomplished by drawing air through a cellulose-fiber filter. These filters were replaced with glass-fiber filters in March 2011. Airborne particulates were collected side by side on the two filter materials between May 2013 and May 2014. Comparisons of the sample mass and the radioactivity determinations for the side-by-side samples were undertaken to determine if the change in the filter medium produced significant results.more » The differences in the results obtained using the two filter types were assessed visually by evaluating the time series and correlation plots and statistically by conducting a nonparametric matched-pair sign test. Generally, the glass-fiber filters collect larger samples of particulates and produce higher radioactivity values for the gross alpha, gross beta, and gamma spectroscopy analyses. However, the correlation between the radioanalytical results for the glass-fiber filters and the cellulose-fiber filters was not strong enough to generate a linear regression function to estimate the glass-fiber filter sample results from the cellulose-fiber filter sample results.« less

  12. Monitoring iodine-129 in air and milk samples collected near the Hanford Site: an investigation of historical iodine monitoring data.

    PubMed

    Fritz, Brad G; Patton, Gregory W

    2006-01-01

    While other research has reported on the concentrations of (129)I in the environment surrounding active nuclear fuel reprocessing facilities, there is a shortage of information regarding how the concentrations change once facilities close. At the Hanford Site, the Plutonium-Uranium Extraction (PUREX) chemical separation plant was operating between 1983 and 1990, during which time (129)I concentrations in air and milk were measured. After the cessation of chemical processing, plant emissions decreased 2.5 orders of magnitude over an 8-year period. An evaluation of (129)I and (127)I concentration data in air and milk spanning the PUREX operation and post-closure period was conducted to compare the changes in environmental levels. Measured concentrations over the monitoring period were below the levels that could result in a potential annual human dose greater than 1 mSv. There was a measurable difference in the measured air concentrations of (129)I at different distances from the source, indicating a distinct Hanford fingerprint. Correlations between stack emissions of (129)I and concentrations in air and milk indicate that atmospheric emissions were the major source of (129)I measured in environmental samples. The measured concentrations during PUREX operations were similar to observations made around a fuel reprocessing plant in Germany. After the PUREX Plant stopped operating, (129)I concentration measurements made upwind of Hanford were similar to the results from Seville, Spain.

  13. Multistage open-tube trap for enrichment of part-per-trillion trace components of low-pressure (below 27-kPa) air samples

    NASA Technical Reports Server (NTRS)

    Ohara, D.; Vo, T.; Vedder, J. F.

    1985-01-01

    A multistage open-tube trap for cryogenic collection of trace components in low-pressure air samples is described. The open-tube design allows higher volumetric flow rates than densely packed glass-bead traps commonly reported and is suitable for air samples at pressures below 27 kPa with liquid nitrogen as the cryogen. Gas blends containing 200 to 2500 parts per trillion by volume each of ethane and ethene were sampled and hydrocarbons were enriched with 100 + or - 4 percent trap efficiency. The multistage design is more efficient than equal-length open-tube traps under the conditions of the measurements.

  14. Calibration of polyurethane foam (PUF) disk passive air samplers for quantitative measurement of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs): factors influencing sampling rates.

    PubMed

    Hazrati, Sadegh; Harrad, Stuart

    2007-03-01

    PUF disk passive air samplers are increasingly employed for monitoring of POPs in ambient air. In order to utilize them as quantitative sampling devices, a calibration experiment was conducted. Time integrated indoor air concentrations of PCBs and PBDEs were obtained from a low volume air sampler operated over a 50 d period alongside the PUF disk samplers in the same office microenvironment. Passive sampling rates for the fully-sheltered sampler design employed in our research were determined for the 51 PCB and 7 PBDE congeners detected in all calibration samples. These values varied from 0.57 to 1.55 m3 d(-1) for individual PCBs and from 1.1 to 1.9 m3 d(-1) for PBDEs. These values are appreciably lower than those reported elsewhere for different PUF disk sampler designs (e.g. partially sheltered) employed under different conditions (e.g. in outdoor air), and derived using different calibration experiment configurations. This suggests that sampling rates derived for a specific sampler configuration deployed under specific environmental conditions, should not be extrapolated to different sampler configurations. Furthermore, our observation of variable congener-specific sampling rates (consistent with other studies), implies that more research is required in order to understand fully the factors that influence sampling rates. Analysis of wipe samples taken from the inside of the sampler housing, revealed evidence that the housing surface scavenges particle bound PBDEs.

  15. Measuring PM2.5, Ultrafine Particles, Nicotine Air and Wipe Samples Following the Use of Electronic Cigarettes.

    PubMed

    Melstrom, Paul; Koszowski, Bartosz; Thanner, Meridith Hill; Hoh, Eunha; King, Brian; Bunnell, Rebecca; McAfee, Tim

    2017-09-01

    Few studies have examined the extent of inhalation or dermal contact among bystanders following short-term, secondhand e-cigarette exposure. Measure PM2.5 (particles < 2.5 microns), UF (ultrafine particles < 100 nm), and nicotine in air and deposited on surfaces and clothing pre-/during/post- a short-term (2-hour) e-cigarette exposure. E-cigarettes were used ad libitum by three experienced users for 2 hours during two separate sessions (disposable e-cigarettes, then tank-style e-cigarettes, or "tanks") in a 1858 ft3 room. We recorded: uncorrected PM2.5 (using SidePak); UF (using P-Trak); air nicotine concentrations (using air samplers; SKC XAD-4 canisters); ambient air exchange rate (using an air capture hood). Wipe samples were taken by wiping 100 cm2 room surfaces pre- and post- both sessions, and clean cloth wipes were worn during the exposure and collected at the end. Uncorrected PM2.5 and UF were higher (p < .0001) during sessions than before or after. Median PM2.5 during exposure was higher using tanks (0.515 mg/m3) than disposables (0.035 mg/m3) (p < .0001). Median UF during exposure was higher using disposables (31 200 particles/cm3) than tanks (25 200 particles/cm3)(p < .0001). Median air nicotine levels were higher (p < .05) during both sessions (disposables = 0.697 ng/L, tanks = 1.833 ng/L) than before (disposables = 0.004 ng/L, tanks = 0.010 ng/L) or after (disposables = 0.115 ng/L, tanks = 0.147 ng/L). Median accumulation rates of nicotine on surface samples were 2.1 ng/100 cm2/h using disposables and 4.0 ng/100 cm2/h using tanks; for cloth samples, it was 44.4 ng/100 cm2/h using disposables and 69.6 ng/100 cm2/h using tanks (p < .01). Mean room ventilation rate was ~5 air changes per hour during both sessions. Short-term e-cigarette use can produce: elevated PM2.5; elevated UF; nicotine in the air; and accumulation of nicotine on surfaces and clothing. Short-term indoor e-cigarette use produced accumulation of nicotine on surfaces and clothing, which

  16. Simultaneous determination of hydroquinone, resorcinol, phenol, m-cresol and p-cresol in untreated air samples using spectrofluorimetry and a custom multiple linear regression-successive projection algorithm.

    PubMed

    Pistonesi, Marcelo F; Di Nezio, María S; Centurión, María E; Lista, Adriana G; Fragoso, Wallace D; Pontes, Márcio J C; Araújo, Mário C U; Band, Beatriz S Fernández

    2010-12-15

    In this study, a novel, simple, and efficient spectrofluorimetric method to determine directly and simultaneously five phenolic compounds (hydroquinone, resorcinol, phenol, m-cresol and p-cresol) in air samples is presented. For this purpose, variable selection by the successive projections algorithm (SPA) is used in order to obtain simple multiple linear regression (MLR) models based on a small subset of wavelengths. For comparison, partial least square (PLS) regression is also employed in full-spectrum. The concentrations of the calibration matrix ranged from 0.02 to 0.2 mg L(-1) for hydroquinone, from 0.05 to 0.6 mg L(-1) for resorcinol, and from 0.05 to 0.4 mg L(-1) for phenol, m-cresol and p-cresol; incidentally, such ranges are in accordance with the Argentinean environmental legislation. To verify the accuracy of the proposed method a recovery study on real air samples of smoking environment was carried out with satisfactory results (94-104%). The advantage of the proposed method is that it requires only spectrofluorimetric measurements of samples and chemometric modeling for simultaneous determination of five phenols. With it, air is simply sampled and no pre-treatment sample is needed (i.e., separation steps and derivatization reagents are avoided) that means a great saving of time. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Oil and gas impacts on air quality in federal lands in the Bakken region: an overview of the Bakken Air Quality Study and first results

    NASA Astrophysics Data System (ADS)

    Prenni, A. J.; Day, D. E.; Evanoski-Cole, A. R.; Sive, B. C.; Hecobian, A.; Zhou, Y.; Gebhart, K. A.; Hand, J. L.; Sullivan, A. P.; Li, Y.; Schurman, M. I.; Desyaterik, Y.; Malm, W. C.; Schichtel, B. A.; Collett, J. L., Jr.

    2015-10-01

    The Bakken formation contains billions of barrels of oil and gas trapped in rock and shale. Horizontal drilling and hydraulic fracturing methods have allowed for extraction of these resources, leading to exponential growth of oil production in the region over the past decade. Along with this development has come an increase in associated emissions to the atmosphere. Concern about potential impacts of these emissions on federal lands in the region prompted the National Park Service to sponsor the Bakken Air Quality Study over two winters in 2013-2014. Here we provide an overview of the study and present some initial results aimed at better understanding the impact of local oil and gas emissions on regional air quality. Data from the study, along with long term monitoring data, suggest that while power plants are still an important emissions source in the region, emissions from oil and gas activities are impacting ambient concentrations of nitrogen oxides and black carbon and may dominate recent observed trends in pollutant concentrations at some of the study sites. Measurements of volatile organic compounds also definitively show that oil and gas emissions were present in almost every air mass sampled over a period of more than four months.

  18. Oil and gas impacts on air quality in federal lands in the Bakken region: an overview of the Bakken Air Quality Study and first results

    NASA Astrophysics Data System (ADS)

    Prenni, A. J.; Day, D. E.; Evanoski-Cole, A. R.; Sive, B. C.; Hecobian, A.; Zhou, Y.; Gebhart, K. A.; Hand, J. L.; Sullivan, A. P.; Li, Y.; Schurman, M. I.; Desyaterik, Y.; Malm, W. C.; Collett, J. L., Jr.; Schichtel, B. A.

    2016-02-01

    The Bakken formation contains billions of barrels of oil and gas trapped in rock and shale. Horizontal drilling and hydraulic fracturing methods have allowed for extraction of these resources, leading to exponential growth of oil production in the region over the past decade. Along with this development has come an increase in associated emissions to the atmosphere. Concern about potential impacts of these emissions on federal lands in the region prompted the National Park Service to sponsor the Bakken Air Quality Study over two winters in 2013-2014. Here we provide an overview of the study and present some initial results aimed at better understanding the impact of local oil and gas emissions on regional air quality. Data from the study, along with long-term monitoring data, suggest that while power plants are still an important emissions source in the region, emissions from oil and gas activities are impacting ambient concentrations of nitrogen oxides and black carbon and may dominate recent observed trends in pollutant concentrations at some of the study sites. Measurements of volatile organic compounds also definitively show that oil and gas emissions were present in almost every air mass sampled over a period of more than 4 months.

  19. Environmental assessment of a crude-oil heater using staged air lances for NOx reduction. Volume 1. Technical results. Final report June 1981-November 1983

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DeRosier, R.

    1984-07-01

    This volume of the report gives emission results from field tests of a crude-oil process heater burning a combination of oil and refinery gas. The heater had been modified by adding a system for injecting secondary air to reduce NOx emissions. One test was conducted with the staged air system (low NOx), and the other, without (baseline). Tests included continuous monitoring of flue gas emissions and source assessment sampling system (SASS) sampling of the flue gas with subsequent laboratory analysis of the samples utilizing gas chromatography (GC), infrared spectrometry (IR), gas chromatography/mass spectroscopy (GC/MS), and low resolution mass spectrometry (SSMS)more » for trace metals. LRMS analysis suggested the presence of eight compound categories in the organic emissions during the baseline test and four in the low-NOx test.« less

  20. Methods for Integrated Air Sampling and DNA Analysis for Detection of Airborne Fungal Spores

    PubMed Central

    Williams, Roger H.; Ward, Elaine; McCartney, H. Alastair

    2001-01-01

    Integrated air sampling and PCR-based methods for detecting airborne fungal spores, using Penicillium roqueforti as a model fungus, are described. P. roqueforti spores were collected directly into Eppendorf tubes using a miniature cyclone-type air sampler. They were then suspended in 0.1% Nonidet P-40, and counted using microscopy. Serial dilutions of the spores were made. Three methods were used to produce DNA for PCR tests: adding untreated spores to PCRs, disrupting spores (fracturing of spore walls to release the contents) using Ballotini beads, and disrupting spores followed by DNA purification. Three P. roqueforti-specific assays were tested: single-step PCR, nested PCR, and PCR followed by Southern blotting and probing. Disrupting the spores was found to be essential for achieving maximum sensitivity of the assay. Adding untreated spores to the PCR did allow the detection of P. roqueforti, but this was never achieved when fewer than 1,000 spores were added to the PCR. By disrupting the spores, with or without subsequent DNA purification, it was possible to detect DNA from a single spore. When known quantities of P. roqueforti spores were added to air samples consisting of high concentrations of unidentified fungal spores, pollen, and dust, detection sensitivity was reduced. P. roqueforti DNA could not be detected using untreated or disrupted spore suspensions added to the PCRs. However, using purified DNA, it was possible to detect 10 P. roqueforti spores in a background of 4,500 other spores. For all DNA extraction methods, nested PCR was more sensitive than single-step PCR or PCR followed by Southern blotting. PMID:11375150

  1. Relative efficiencies of two air sampling methods and three culture conditions for the assessment of airborne culturable fungi in a poultry farmhouse in France.

    PubMed

    Nieguitsila, Adélaïde; Arné, Pascal; Durand, Benoît; Deville, Manjula; Benoît-Valiergue, Hélène; Chermette, René; Cottenot-Latouche, Sophie; Guillot, Jacques

    2011-02-01

    Fungal elements represent a significant part of the biological contaminants that could be detected in the air of animal facilities. The aim of this study was to assess the relative efficiencies of two air sampling methods and three culture conditions for the quantification of airborne culturable fungi in a poultry farmhouse in France. Air samples were collected every week throughout a 15-week period. Two devices were simultaneously used-a rotative cup air sampler (CIP 10-M, Arelco, France) and an air sampler based on filtration (AirPort MD8, Sartorius, Germany). Culture of airborne viable fungi was performed on malt extract agar (ME) and dichloran glycerol-18 (DG18) at 25 or 37°C. CIP 10-M and AirPort MD8 were shown to display comparable performances but significant differences were observed between culture conditions for Aspergillus spp. (p<0.01), Scopulariopsis spp. (p=0.02) and unidentified molds (p<0.01). Copyright © 2010 Elsevier Inc. All rights reserved.

  2. The value and limitations of global air-sampling networks for improving our understanding trace gas behavior

    NASA Astrophysics Data System (ADS)

    Montzka, S. A.

    2016-12-01

    Measurements from global surface-based air sampling networks provide a fundamental understanding of how and why concentrations of long-lived trace gases are changing over time. Results from these networks are used to quantify trace-gas concentrations and their time-dependent changes on global and smaller scales, and thus provide a means to quantify emission rates, loss frequencies, and mixing processes. Substantial advances in measurement and sampling technologies and the ability of these programs to create and maintain reliable gas standards mean that spatial concentration gradients and time-dependent changes are often very reliably measured. The presence of multiple independent networks allows an assessment of this reliability. Furthermore, recent global `snap-shot' surveys (e.g., HIPPO and ATom) and ongoing atmospheric profiling programs help us assess the ability of surface-based data to describe concentration distributions throughout most of the atmosphere ( 80% of its mass). In this overview talk, I'll explore the usefulness and limitations of existing long-term, ongoing sampling network programs and their advantages and disadvantages for characterizing concentrations on global and regional scales, and how recent advances (and short-term sampling programs) help us assess the accuracy of the surface networks to provide estimates of source and sink magnitudes, and inter-annual variability in both.

  3. CTEPP STANDARD OPERATING PROCEDURE FOR EXTRACTING AND PREPARING AIR SAMPLES FOR ANALYSIS OF POLAR PERSISTENT ORGANIC POLLUTANTS (SOP-5.13)

    EPA Science Inventory

    The method for extracting and preparing indoor and outdoor air samples for analysis of polar persistent organic pollutants is summarized in this SOP. It covers the preparation of samples that are to be analyzed by gas chromatography/mass spectrometry.

  4. Vapor-phase and particulate-associated pesticides and PCB concentrations in eastern North Dakota air samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hawthorne, S.B.; Miller, D.J.; Louie, P.K.K.

    1996-05-01

    Vapor-phase and suspended particulate (<50 {mu}m) samples were collected on polyurethane foam (PUF) and quartz fiber filters in rural North Dakota to determine the air concentrations of pesticides in an area where agriculture is a primary source of semivolatile pollutants. Samples were collected at two sites from 1992 to 1994 that were at least 0.4 km from the nearest farmed fields and known application of pesticides, and analyzed for 22 different organochlorine, triazine, and acid herbicide pesticides. Fourteen pesticides were found above the detection limits (typically <1 pg/m{sup 3}). Concentrations of polychlorinated biphenyl (PCB) congeners were much lower (<50 pg/m{supmore » 3} in all cases) than many of the pesticides. These results demonstrate that pesticides are among the most prevalent chlorinated semivolatile pollutants present in rural North Dakota, that significant transport of pesticides occurs both in the vapor-phase and on suspended particulate matter, and that blown soil may be a significant mechanism for introducing pesticides into surface and ground waters. 32 refs., 2 figs., 4 tabs.« less

  5. COMPARISON OF MOLD CONCENTRATIONS IN INDOOR AND OUTDOOR AIR SAMPLED SIMULTANEOUSLY AND THEN QUANTIFIED BY MSQPCR

    EPA Science Inventory

    Mold specific quantitative PCR (MSQPCR) was used to measure the concentrations of the 36 mold species in indoor and outdoor air samples that were taken simultaneously for 48 hours in and around 17 homes in Cincinnati, Ohio. The total spore concentrations of 353 per m3...

  6. STATISTICAL ANALYSIS OF TANK 5 FLOOR SAMPLE RESULTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, E.

    2012-03-14

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, radionuclide, inorganic, and anion concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above

  7. Statistical Analysis of Tank 5 Floor Sample Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, E. P.

    2013-01-31

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide1, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some

  8. Statistical Analysis Of Tank 5 Floor Sample Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, E. P.

    2012-08-01

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some

  9. Sample Results from MCU Solids Outage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peters, T.; Washington, A.; Oji, L.

    2014-09-22

    Savannah River National Laboratory (SRNL) has received several solid and liquid samples from MCU in an effort to understand and recover from the system outage starting on April 6, 2014. SRNL concludes that the presence of solids in the Salt Solution Feed Tank (SSFT) is the likely root cause for the outage, based upon the following discoveries: A solids sample from the extraction contactor #1 proved to be mostly sodium oxalate; A solids sample from the scrub contactor#1 proved to be mostly sodium oxalate; A solids sample from the Salt Solution Feed Tank (SSFT) proved to be mostly sodium oxalate;more » An archived sample from Tank 49H taken last year was shown to contain a fine precipitate of sodium oxalate; A solids sample from ; A liquid sample from the SSFT was shown to have elevated levels of oxalate anion compared to the expected concentration in the feed. Visual inspection of the SSFT indicated the presence of precipitated or transferred solids, which were likely also in the Salt Solution Receipt Tank (SSRT). The presence of the solids coupled with agitation performed to maintain feed temperature resulted in oxalate solids migration through the MCU system and caused hydraulic issues that resulted in unplanned phase carryover from the extraction into the scrub, and ultimately the strip contactors. Not only did this carryover result in the Strip Effluent (SE) being pushed out of waste acceptance specification, but it resulted in the deposition of solids into several of the contactors. At the same time, extensive deposits of aluminosilicates were found in the drain tube in the extraction contactor #1. However it is not known at this time how the aluminosilicate solids are related to the oxalate solids. The solids were successfully cleaned out of the MCU system. However, future consideration must be given to the exclusion of oxalate solids into the MCU system. There were 53 recommendations for improving operations recently identified. Some additional

  10. Avian and Herpetological Survey Results for Fairchild Air Force Base and Ancillary Properties

    DTIC Science & Technology

    2014-10-02

    unlimited. The US Army Engineer Research and Development Center (ERDC) solves the nation’s toughest engineering and environmental challenges. ERDC...Herpetological Survey Results for Fairchild Air Force Base and Ancillary Properties Jinelle H. Sperry Construction Engineering Research Laboratory (CERL) US ...Air Force Base (FAFB) and used survey results to extrapolate guidelines for species management. DISCLAIMER: The contents of this report are not to be

  11. A novel, fuzzy-based air quality index (FAQI) for air quality assessment

    NASA Astrophysics Data System (ADS)

    Sowlat, Mohammad Hossein; Gharibi, Hamed; Yunesian, Masud; Tayefeh Mahmoudi, Maryam; Lotfi, Saeedeh

    2011-04-01

    The ever increasing level of air pollution in most areas of the world has led to development of a variety of air quality indices for estimation of health effects of air pollution, though the indices have their own limitations such as high levels of subjectivity. Present study, therefore, aimed at developing a novel, fuzzy-based air quality index (FAQI ) to handle such limitations. The index developed by present study is based on fuzzy logic that is considered as one of the most common computational methods of artificial intelligence. In addition to criteria air pollutants (i.e. CO, SO 2, PM 10, O 3, NO 2), benzene, toluene, ethylbenzene, xylene, and 1,3-butadiene were also taken into account in the index proposed, because of their considerable health effects. Different weighting factors were then assigned to each pollutant according to its priority. Trapezoidal membership functions were employed for classifications and the final index consisted of 72 inference rules. To assess the performance of the index, a case study was carried out employing air quality data at five different sampling stations in Tehran, Iran, from January 2008 to December 2009, results of which were then compared to the results obtained from USEPA air quality index (AQI). According to the results from present study, fuzzy-based air quality index is a comprehensive tool for classification of air quality and tends to produce accurate results. Therefore, it can be considered useful, reliable, and suitable for consideration by local authorities in air quality assessment and management schemes. Fuzzy-based air quality index (FAQI).

  12. STS 129 Return Samples: Assessment of Air Quality aboard the Shuttle (STS-129) and International Space Station (ULF3)

    NASA Technical Reports Server (NTRS)

    James, John T.

    2010-01-01

    Reports on the air quality aboard the Space Shuttle (STS-129), and the International Space station (ULF3). NASA analyzed the grab sample canisters (GSCs) and the formaldehyde badges aboard both locations for carbon monoxide levels. The three surrogates: (sup 13)C-acetone, fluorobenzene, and chlorobenzene registered 109, 101, and 109% in the space shuttle and 81, 87, and 55% in the International Space Station (ISS). From these results the atmosphere in both the Space Shuttle and the International Space Station (ISS) was found to be breathable.

  13. Atmospheric CO2 Records from Sites in the Scripps Institution of Oceanography (SIO) Air Sampling Network (1985 - 2007)

    DOE Data Explorer

    Keeling, R. F. [Scripps Institution of Oceanography (SIO) University of California, La Jolla, California (USA); Piper, S. C. [Scripps Institution of Oceanography (SIO) University of California, La Jolla, California (USA); Bollenbacher, A. F. [Scripps Institution of Oceanography (SIO) University of California, La Jolla, California (USA); Walker , J. S. [Scripps Institution of Oceanography (SIO) University of California, La Jolla, California (USA)

    2008-05-01

    At Alert weekly air samples are collected in 5-L evacuated glass flasks exposed in triplicate. Flasks are returned to the SIO for CO2 determinations, which are made using an Applied Physics Corporation nondispersive infrared gas analyzer. In May 1983, the CO2-in-N2 calibration gases were replaced with CO2-in-air calibration gases, which are currently used (Keeling et al. 2002). Data are in terms of the Scripps "03A" calibration scale. On the basis of flask samples collected at Alert and analyzed by SIO, the annual average of the fitted monthly concentrations CO2 rose from 348.48 ppmv in 1986 to 384.84 ppmv in 2007. This represents an average annual growth rate of 1.73 ppmv per year at Alert.

  14. Changes to indoor air quality as a result of relocating families from slums to public housing

    NASA Astrophysics Data System (ADS)

    Burgos, Soledad; Ruiz, Pablo; Koifman, Rosalina

    2013-05-01

    One largely unstudied benefit of relocating families from slums to public housing is the potential improvement in indoor air quality (IAQ). We compared families that moved from slums to public housing with those that remained living in slums in Santiago, Chile in terms of fine particulate matter (PM2.5) as main indicator of change. A cross-sectional study of 98 relocated families and 71 still living in slums was carried out, obtaining indoor and outdoor samples by a Personal Environmental Monitor. Home characteristics, including indoor air pollution sources were collected through questionnaires. Multivariate regression models included the intervention (public housing or slum), indoor pollution sources, outdoor PM2.5 and family characteristics as predictors. Indoor PM2.5 concentrations were higher in slums (77.8 μg m-3 [SD = 35.7 μg m-3]) than in public housing (55.7 μg m-3 [SD = 34.6 μg m-3], p < 0.001). Differences between indoor and outdoor PM2.5 were significant only in the slum houses. The multivariate analysis showed that housing intervention significantly decreased indoor PM2.5 (10.4 μg m-3) after adjusting by the other predictors. Outdoor PM2.5 was the main predictor of indoor PM2.5. Other significant factors were water heating fuels and indoor smoking. Having infants 1-23 months was associated with a lowering of indoor PM2.5. Our results suggest that a public housing program that moves families from slums to public housing improves indoor air quality directly and also indirectly through air pollution sources.

  15. Collection and analysis of NASA clean room air samples

    NASA Technical Reports Server (NTRS)

    Sheldon, L. S.; Keever, J.

    1985-01-01

    The environment of the HALOE assembly clean room at NASA Langley Research Center is analyzed to determine the background levels of airborne organic compounds. Sampling is accomplished by pumping the clean room air through absorbing cartridges. For volatile organics, cartridges are thermally desorbed and then analyzed by gas chromatography and mass spectrometry, compounds are identified by searching the EPA/NIH data base using an interactive operator INCOS computer search algorithm. For semivolatile organics, cartridges are solvent entracted and concentrated extracts are analyzed by gas chromatography-electron capture detection, compound identification is made by matching gas chromatogram retention times with known standards. The detection limits for the semivolatile organics are; 0.89 ng cu m for dioctylphlhalate (DOP) and 1.6 ng cu m for polychlorinated biphenyls (PCB). The detection limit for volatile organics ranges from 1 to 50 parts per trillion. Only trace quantities of organics are detected, the DOP levels do not exceed 2.5 ng cu m and the PCB levels do not exceed 454 ng cu m.

  16. An evaluation of analytical methods, air sampling techniques, and airborne occupational exposure of metalworking fluids.

    PubMed

    Verma, Dave K; Shaw, Don S; Shaw, M Lorraine; Julian, Jim A; McCollin, Shari-Ann; des Tombe, Karen

    2006-02-01

    This article summarizes an assessment of air sampling and analytical methods for both oil and water-based metalworking fluids (MWFs). Three hundred and seventy-four long-term area and personal airborne samples were collected at four plants using total (closed-face) aerosol samplers and thoracic samplers. A direct-reading device (DustTrak) was also used. The processes sampled include steel tube making, automotive component manufacturing, and small part manufacturing in a machine shop. The American Society for Testing and Materials (ASTM) Method PS42-97 of analysis was evaluated in the laboratory. This evaluation included sample recovery, determination of detection limits, and stability of samples during storage. Results of the laboratory validation showed (a) the sample recovery to be about 87%, (b) the detection limit to be 35 microg, and (c) sample stability during storage at room temperature to decline rapidly within a few days. To minimize sample loss, the samples should be stored in a freezer and analyzed within a week. The ASTM method should be the preferred method for assessing metalworking fluids (MWFs). The ratio of thoracic aerosol to total aerosol ranged from 0.6 to 0.7. A similar relationship was found between the thoracic extractable aerosol and total extractable aerosol. The DustTrak, with 10-microm sampling head, was useful in pinpointing the areas of potential exposure. MWF exposure at the four plants ranged from 0.04 to 3.84 mg/m3 with the geometric mean ranging between 0.22 to 0.59 mg/m3. Based on this data and the assumption of log normality, MWF exposures are expected to exceed the National Institute for Occupational Safety and Health recommended exposure limit of 0.5 mg/m3 as total mass and 0.4 mg/m3 as thoracic mass about 38% of the time. In addition to controlling airborne MWF exposure, full protection of workers would require the institution of programs for fluid management and dermal exposure prevention.

  17. Comparison of halocarbon measurements in an atmospheric dry whole air sample.

    PubMed

    Rhoderick, George C; Hall, Bradley D; Harth, Christina M; Kim, Jin Seog; Lee, Jeongsoon; Montzka, Stephen A; Mühle, Jens; Reimann, Stefan; Vollmer, Martin K; Weiss, Ray F

    The growing awareness of climate change/global warming, and continuing concerns regarding stratospheric ozone depletion, will require continued measurements and standards for many compounds, in particular halocarbons that are linked to these issues. In order to track atmospheric mole fractions and assess the impact of policy on emission rates, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. Precise measurements of these species aid in determining small changes in their atmospheric abundance. A common source of standards/scales and/or well-documented agreement of different scales used to calibrate the measurement instrumentation are key to understanding many sets of data reported by researchers. This report describes the results of a comparison study among National Metrology Institutes and atmospheric research laboratories for the chlorofluorocarbons (CFCs) dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11), and 1,1,2-trichlorotrifluoroethane (CFC-113); the hydrochlorofluorocarbons (HCFCs) chlorodifluoromethane (HCFC-22) and 1-chloro-1,1-difluoroethane (HCFC-142b); and the hydrofluorocarbon (HFC) 1,1,1,2-tetrafluoroethane (HFC-134a), all in a dried whole air sample. The objective of this study is to compare calibration standards/scales and the measurement capabilities of the participants for these halocarbons at trace atmospheric levels. The results of this study show agreement among four independent calibration scales to better than 2.5% in almost all cases, with many of the reported agreements being better than 1.0%.

  18. Comparison of halocarbon measurements in an atmospheric dry whole air sample

    PubMed Central

    Hall, Bradley D.; Harth, Christina M.; Kim, Jin Seog; Lee, Jeongsoon; Montzka, Stephen A.; Mühle, Jens; Reimann, Stefan; Vollmer, Martin K.; Weiss, Ray F.

    2015-01-01

    The growing awareness of climate change/global warming, and continuing concerns regarding stratospheric ozone depletion, will require continued measurements and standards for many compounds, in particular halocarbons that are linked to these issues. In order to track atmospheric mole fractions and assess the impact of policy on emission rates, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. Precise measurements of these species aid in determining small changes in their atmospheric abundance. A common source of standards/scales and/or well-documented agreement of different scales used to calibrate the measurement instrumentation are key to understanding many sets of data reported by researchers. This report describes the results of a comparison study among National Metrology Institutes and atmospheric research laboratories for the chlorofluorocarbons (CFCs) dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11), and 1,1,2-trichlorotrifluoroethane (CFC-113); the hydrochlorofluorocarbons (HCFCs) chlorodifluoromethane (HCFC-22) and 1-chloro-1,1-difluoroethane (HCFC-142b); and the hydrofluorocarbon (HFC) 1,1,1,2-tetrafluoroethane (HFC-134a), all in a dried whole air sample. The objective of this study is to compare calibration standards/scales and the measurement capabilities of the participants for these halocarbons at trace atmospheric levels. The results of this study show agreement among four independent calibration scales to better than 2.5% in almost all cases, with many of the reported agreements being better than 1.0%. PMID:26753167

  19. CTEPP STANDARD OPERATING PROCEDURE FOR EXTRACTING AND PREPARING AIR SAMPLES FOR ANALYSIS OF NEUTRAL PERSISTENT ORGANIC POLLUTANTS (SOP-5.12)

    EPA Science Inventory

    The method is for extracting an indoor and outdoor air sample consisting of a quartz fiber filter and an XAD-2 cartridge for analysis of neutral persistent organic pollutants. It covers the extraction and concentration of samples that are to be analyzed by gas chromatography/mass...

  20. Evaluating and improving the results of air quality models in Texas using TES, AIRS and other satellite data

    NASA Astrophysics Data System (ADS)

    Osterman, G.; Harper, C.; Estes, M.; Zhao, W.; Bowman, K.; Pierce, B.; Irion, B.; Kahn, B.; Al-Saadi, J.

    2008-05-01

    The Houston/Galveston/Brazoria (HGB) area of Texas has been classified as in moderate nonattainment of the Environmental Protection Agency (EPA) 8-hour standard for ground level ozone since April 30, 2004. The Texas Commission on Environmental Quality uses photochemical model results as one of its primary tools to develop strategies to bring the HGB area into attainment with the EPA standard. The state of Texas then includes the strategies into a revised version of its State Implementation Plan (SIP). We will discuss efforts that have been or soon will be underway to use satellite data to evaluate and improve the meteorological and photochemical modeling efforts at TCEQ. In particular we will show the use of GOES, AIRS and TES data to improve the ability to model, using the MM5 model, the meteorological conditions over Texas and the Gulf of Mexico. The meteorological fields are then used as one of the inputs to the CAMx air quality model used at TCEQ. We will discuss the use of chemical transport model results as initial and boundary conditions which are a key uncertainty in the modeling of the air above Houston. We will also discuss the use of TES data to assist in the evaluation of preliminary model results generated by TCEQ for time periods in 2005. The satellite data will provide key information on ozone and carbon monoxide concentrations away from surface monitors in the troposphere. We will show how satellite data is becoming a key tool in the effort to improve air quality in the HGB area and one that can easily applied for use in other regions of the country.

  1. Evaluation of silica-gel cartridges coated in situ with acidified 2,4-dinitrophenylhydrazine for sampling aldehydes and ketones in air

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tejada, S.B.

    1986-01-01

    A procedure for coating in-situ silica in commercially available prepacked cartridges with 2,4-dinitrophenylhydrazine (DNPH) acidified with hydrochloric acid is described. The coated cartridge was compared with a validated DNPH impinger method for sampling organic carbonyl compounds (aldehydes and ketones) in diluted automotive exhaust emissions and in ambient air for subsequent analysis of the DNPH derivatives by high performance liquid chromatography. Qualitative and quantitative results show that the two sampling devices are equivalent. An unknown degradation product of acrolein has been tentatively identified as x-acrolein. The disappearance of acrolein in the analytical sample matrix correlated quantitatively almost on a mole-for-mole basismore » with the growth of x-acrolein. The sum of the concentration of acrolein and x-acrolein appears to be invariant with time. This sum could possibly be used as a more-accurate value of the concentration of acrolein in the integratated sample.« less

  2. Air Pollution Source/receptor Relationships in South Coast Air Basin, CA

    NASA Astrophysics Data System (ADS)

    Gao, Ning

    This research project includes the application of some existing receptor models to study the air pollution source/receptor relationships in the South Coast Air Basin (SoCAB) of southern California, the development of a new receptor model and the testing and the modifications of some existing models. These existing receptor models used include principal component factor analysis (PCA), potential source contribution function (PSCF) analysis, Kohonen's neural network combined with Prim's minimal spanning tree (TREE-MAP), and direct trilinear decomposition followed by a matrix reconstruction. The ambient concentration measurements used in this study are a subset of the data collected during the 1987 field exercise of Southern California Air Quality Study (SCAQS). It consists of a number of gaseous and particulate pollutants analyzed from samples collected by SCAQS samplers at eight sampling sites, Anaheim, Azusa, Burbank, Claremont, Downtown Los Angeles, Hawthorne, Long Beach, and Rubidoux. Based on the information of emission inventories, meteorology and ambient concentrations, this receptor modeling study has revealed mechanisms that influence the air quality in SoCAB. Some of the mechanisms affecting the air quality in SoCAB that were revealed during this study include the following aspects. The SO_2 collected at sampling sites is mainly contributed by refineries in the coastal area and the ships equipped with oil-fired boilers off shore. Combustion of fossil fuel by automobiles dominates the emission of NO_{rm x} that is subsequently transformed and collected at sampling sites. Electric power plants also contribute HNO_3 to the sampling sites. A large feedlot in the eastern region of SoCAB has been identified as the major source of NH_3. Possible contributions from other industrial sources such as smelters and incinerators were also revealed. The results of this study also suggest the possibility of DMS (dimethylsulfide) and NH_3 emissions from off-shore sediments

  3. Particulate sulphate and ozone in rural air: Preliminary results from three sites in central England

    NASA Astrophysics Data System (ADS)

    Martin, A.; Barber, F. R.

    Daily particulate sulphate concentrations in air have been measured at a 'background' rural site and at two other sites near rural power stations. The samples were collected by drawing air through filter papers and were analysed by X-ray fluorescence. At the background site the concentration of particulate sulphates was strongly dependent on the O 3 and total S in air. Above a certain 'critical' level of daily O 3, 28% of the daily S in air was particulate on average, but the amounts were not related to the actual O 3 levels. At lower O 3 levels, there appeared to be a constant background of about 2 μg of particulate sulphate per cubic meter of air, together with about 5% of the total S in air as particulate. When black smoke in air was low, the particulate sulphate was also low, despite the O 3 levels. Near the power stations, there was no significantly different rate of production or loss of particulate sulphate. On average, at all three sites over the year, about 12% of the daily total S was particulate, probably corresponding to an average conversion rate of SO 2 of less than 1% per hour. Estimates of hourly particulate sulphates are available from previous measurements at the background site, using a different analysis technique. Particulate sulphate was not found every hour, but typically during 20 h a day in early summer and 8 h a day in early winter. An influence of humidity as well as O 3 was apparent in the peak hourly particulate sulphate values, which reached 60% of the total S. No correlation could be found of particulate sulphate with solar radiation, wind direction, concentrations of oxides of nitrogen in air or ammonium or sulphate in rainwater, but further measurements are planned.

  4. 6S Return Samples: Assessment of Air Quality in the International Space Station (ISS) Based on Solid Sorbent Air Sampler (SSAS) and Formaldehyde Monitoring Kit (FMK) Analyses

    NASA Technical Reports Server (NTRS)

    James, John T.

    2004-01-01

    The toxicological assessments of SSAS and FMK analytical results are reported. Analytical methods have not changed from earlier reports. Surrogate standard recoveries from the SSAS tubes were 66-76% for 13C-acetone, 85-96% for fluorobenzene, and 73-89% for chlorobenzene. Post-flight flows were far below pre-flight flows and an investigation of the problem revealed that the reduced flow was caused by a leak at the interface of the pump inlet tube and the pump head. This resulted in degradation of pump efficiency. Further investigation showed that the problem occurred before the SSAS was operated on orbit and that use of the post-flight flows yielded consistent and useful results. Recoveries from formaldehyde control badges were 86 to 104%. The two general criteria used to assess air quality are the total-non-methane-volatile organic hydrocarbons (NMVOCs) and the total T-value (minus the CO2 and formaldehyde contributions). The T values will not be reported for these data due to the flow anomaly. Control of atmospheric alcohols is important to the water recovery system engineers, hence total alcohols (including acetone) are also shown for each sample. Octafluoropropane (OFP) is not efficiently trapped by the sorbents used in the SSAS. Because formaldehyde is quantified from sorbent badges, its concentration is also listed separately. These five indices of air quality are summarized.

  5. Sample Results From Tank 48H Samples HTF-48-14-158, -159, -169, and -170

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peters, T.; Hang, T.

    2015-04-28

    Savannah River National Laboratory (SRNL) analyzed samples from Tank 48H in support of determining the cause for the unusually high dose rates at the sampling points for this tank. A set of two samples was taken from the quiescent tank, and two additional samples were taken after the contents of the tank were mixed. The results of the analyses of all the samples show that the contents of the tank have changed very little since the analysis of the previous sample in 2012. The solids are almost exclusively composed of tetraphenylborate (TPB) salts, and there is no indication of accelerationmore » in the TPB decomposition. The filtrate composition shows a moderate increase in salt concentration and density, which is attributable to the addition of NaOH for the purposes of corrosion control. An older modeling simulation of the TPB degradation was updated, and the supernate results from a 2012 sample were run in the model. This result was compared to the results from the 2014 recent sample results reported in this document. The model indicates there is no change in the TPB degradation from 2012 to 2014. SRNL measured the buoyancy of the TPB solids in Tank 48H simulant solutions. It was determined that a solution of density 1.279 g/mL (~6.5M sodium) was capable of indefinitely suspending the TPB solids evenly throughout the solution. A solution of density 1.296 g/mL (~7M sodium) caused a significant fraction of the solids to float on the solution surface. As the experiments could not include the effect of additional buoyancy elements such as benzene or hydrogen generation, the buoyancy measurements provide an upper bound estimate of the density in Tank 48H required to float the solids.« less

  6. US EPA Base Study Standard Operating Procedure for Sampling Volatile Organic Compounds in Indoor Air Using Evacuated Canisters

    EPA Pesticide Factsheets

    The objective of this procedure is to collect a representative sample of air containing volatile organic compound (VOC) contaminants present in an indoor environment using an evacuated canister, and to subsequently analyze the concentration of VOCs, as selected by EPA.

  7. Evaluation of Observation-Fused Regional Air Quality Model Results for Population Air Pollution Exposure Estimation

    PubMed Central

    Chen, Gang; Li, Jingyi; Ying, Qi; Sherman, Seth; Perkins, Neil; Rajeshwari, Sundaram; Mendola, Pauline

    2014-01-01

    In this study, Community Multiscale Air Quality (CMAQ) model was applied to predict ambient gaseous and particulate concentrations during 2001 to 2010 in 15 hospital referral regions (HRRs) using a 36-km horizontal resolution domain. An inverse distance weighting based method was applied to produce exposure estimates based on observation-fused regional pollutant concentration fields using the differences between observations and predictions at grid cells where air quality monitors were located. Although the raw CMAQ model is capable of producing satisfying results for O3 and PM2.5 based on EPA guidelines, using the observation data fusing technique to correct CMAQ predictions leads to significant improvement of model performance for all gaseous and particulate pollutants. Regional average concentrations were calculated using five different methods: 1) inverse distance weighting of observation data alone, 2) raw CMAQ results, 3) observation-fused CMAQ results, 4) population-averaged raw CMAQ results and 5) population-averaged fused CMAQ results. It shows that while O3 (as well as NOx) monitoring networks in the HRR regions are dense enough to provide consistent regional average exposure estimation based on monitoring data alone, PM2.5 observation sites (as well as monitors for CO, SO2, PM10 and PM2.5 components) are usually sparse and the difference between the average concentrations estimated by the inverse distance interpolated observations, raw CMAQ and fused CMAQ results can be significantly different. Population-weighted average should be used to account spatial variation in pollutant concentration and population density. Using raw CMAQ results or observations alone might lead to significant biases in health outcome analyses. PMID:24747248

  8. Breathing zone air sampler

    DOEpatents

    Tobin, John

    1989-01-01

    A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  9. Exploring prenatal outdoor air pollution, birth outcomes and neonatal health care utilization in a nationally representative sample

    PubMed Central

    Trasande, Leonardo; Wong, Kendrew; Roy, Angkana; Savitz, David A.; Thurston, George

    2015-01-01

    The impact of air pollution on fetal growth remains controversial, in part, because studies have been limited to sub-regions of the United States with limited variability. No study has examined air pollution impacts on neonatal health care utilization. We performed descriptive, univariate and multivariable analyses on administrative hospital record data from 222,359 births in the 2000, 2003 and 2006 Kids Inpatient Database linked to air pollution data drawn from the US Environmental Protection Agency’s Aerometric Information Retrieval System. In this study, air pollution exposure during the birth month was estimated based on birth hospital address. Although air pollutants were not individually associated with mean birth weight, a three-pollutant model controlling for hospital characteristics, demographics, and birth month identified 9.3% and 7.2% increases in odds of low birth weight and very low birth weight for each µg/m3 increase in PM2.5 (both P<0.0001). PM2.5 and NO2 were associated with −3.0% odds/p.p.m. and +2.5% odds/p.p.b. of preterm birth, respectively (both P<0.0001). A four-pollutant multivariable model indicated a 0.05 days/p.p.m. NO2 decrease in length of the birth hospitalization (P=0.0061) and a 0.13 days increase/p.p.m. CO (P=0.0416). A $1166 increase in per child costs was estimated for the birth hospitalization per p.p.m. CO (P=0.0002) and $964 per unit increase in O3 (P=0.0448). A reduction from the 75th to the 25th percentile in the highest CO quartile for births predicts annual savings of $134.7 million in direct health care costs. In a national, predominantly urban, sample, air pollutant exposures during the month of birth are associated with increased low birth weight and neonatal health care utilization. Further study of this database, with enhanced control for confounding, improved exposure assessment, examination of exposures across multiple time windows in pregnancy, and in the entire national sample, is supported by these initial

  10. Assessment of Air Quality in the Shuttle and International Space Station (ISS) Based on Samples Returned by STS-102 at the Conclusion of 5A.1

    NASA Technical Reports Server (NTRS)

    James, John T.

    2001-01-01

    The toxicological assessment of air samples returned at the end of the STS-102 (5A.1) flight to the ISS is reported. ISS air samples were taken in late February 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges . A "first-entry" sample of the multipurpose logistics module (MPLM) atmosphere was taken with a GSC, and preflight and end-of-mission samples were obtained from Discovery using GSCs. Analytical methods have not changed from earlier reports, and all quality control measures were met for the data presented herein. The two general criteria used to assess air quality are the total-non-methane-volatile organic hydrocarbons (NMVOCs) and the total T-value (minus the CO2 contribution). Control of atmospheric alcohols is important to the water recovery system engineers, hence total alcohols were also assessed in each sample. Formaldehyde is quantified separately.

  11. Monitoring Iodine-129 in Air and Milk Samples Collected Near the Hanford Site: An Investigation of Historical Iodine Monitoring Data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fritz, Brad G.; Patton, Gregory W.

    2006-01-01

    While other research has reported on the concentrations of 129I in the environment surrounding active nuclear fuel reprocessing facilities, there is a shortage of information regarding how the concentrations change once facilities close. At the Hanford Site, the Plutonium-Uranium Extraction (PUREX) chemical separation plant was operational between 1983 and 1990, during which time 129I concentrations in air and milk were measured. After the cessation of operations in 1990, plant emissions decreased 2.5 orders of magnitude over an 8 year period, and monitoring of environmental levels continued. An evaluation of air and milk 129I concentration data spanning the PUREX operation andmore » post closure period was conducted to compare the changes in environmental levels of 129I measured. Measured concentrations over the monitoring period were below levels that could result in a potential human dose greater than 10 uSv. There was a significant and measurable difference in the measured air concentrations of 129I at different distances from the source, indicating a distinct Hanford fingerprint. Correlations between stack emissions of 129I and concentrations in air and milk indicate that atmospheric emissions were responsible for the 129I concentrations measured in environmental samples. The measured concentrations during PUREX operation were similar to observations made around a fuel reprocessing plant in Germany.« less

  12. The study of volatile organic compounds in urban and indoor air

    NASA Astrophysics Data System (ADS)

    Clarkson, Paul Jonathan

    Chapter 1 is a review of the literature concerning the study of volatile organic compounds in the atmosphere. It examines the basic chemistry of the atmosphere and the roles that organic compounds play in it. Also investigated are the methods of sampling and analysing the volatile organic compounds in the air, paying particular attention to the role of solid phase sampling. Chapter 1 also examines the role of volatile organic compounds on air quality. Chapter 2 describes the experimental procedures that were employed during the course of this research project. Chapter 3 examines a multi-method approach to the study of volatile organic compounds in urban and indoor air. The methods employed were capillary electrophoresis, high performance liquid chromatography and gas chromatography. Although good results were obtained for the various methods that were investigated Chapter 3 concludes that a more unified analytical approach is needed to the study of the air. Chapter 4 investigates the possibilities of using a unified approach to the study of VOC's. This is achieved by the development of an air sampling method that uses solid phase extraction cartridges. By investigating many aspects of air sampling mechanisms the results show that a simple yet efficient method for the sampling of VOC in air has been developed. The SPE method is a reusable, yet reliable method that by using sequential solvent desorption has been shown to exhibit some degree of selectivity. The solid phase that gave the best results was styrene-divinyl benzene however other phases were also investigated. The use of a single gas chromatography method was also investigated for the purpose of confirmatory identification of the VOC's. Various detection systems were used including MS and AED. It was shown that by optimising the GC's it was possible to get complimentary results. Also investigated was the possibility of compound tagging in an attempt to confirm the identity of several of the compounds found

  13. Assessment of Air Quality in the Shuttle and International Space Station (ISS) Based on Samples Returned by STS-105 at the Conclusion of 7A.1

    NASA Technical Reports Server (NTRS)

    James, John T.

    2001-01-01

    The toxicological assessment of air samples returned at the end of the STS-105 (7 A.1) flight to the ISS is reported. ISS air samples were taken in August 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges. Preflight and end-of-mission samples were obtained from Discovery using GSCs. Analytical methods have not changed from earlier reports, and surrogate standard recoveries were 64-115%. Pressure tracking indicated no leaks in the canisters.

  14. Use of respondent driven sampling (RDS) generates a very diverse sample of men who have sex with men (MSM) in Buenos Aires, Argentina.

    PubMed

    Carballo-Diéguez, Alex; Balan, Ivan; Marone, Rubén; Pando, María A; Dolezal, Curtis; Barreda, Victoria; Leu, Cheng-Shiun; Avila, María Mercedes

    2011-01-01

    Prior research focusing on men who have sex with men (MSM) conducted in Buenos Aires, Argentina, used convenience samples that included mainly gay identified men. To increase MSM sample representativeness, we used Respondent Driven Sampling (RDS) for the first time in Argentina. Using RDS, under certain specified conditions, the observed estimates for the percentage of the population with a specific trait are asymptotically unbiased. We describe, the diversity of the recruited sample, from the point of view of sexual orientation, and contrast the different subgroups in terms of their HIV sexual risk behavior. 500 MSM were recruited using RDS. Behavioral data were collected through face-to-face interviews and Web-based CASI. In contrast with prior studies, RDS generated a very diverse sample of MSM from a sexual identity perspective. Only 24.5% of participants identified as gay; 36.2% identified as bisexual, 21.9% as heterosexual, and 17.4% were grouped as "other." Gay and non-gay identified MSM differed significantly in their sexual behavior, the former having higher numbers of partners, more frequent sexual contacts and less frequency of condom use. One third of the men (gay, 3%; bisexual, 34%, heterosexual, 51%; other, 49%) reported having had sex with men, women and transvestites in the two months prior to the interview. This population requires further study and, potentially, HIV prevention strategies tailored to such diversity of partnerships. Our results highlight the potential effectiveness of using RDS to reach non-gay identified MSM. They also present lessons learned in the implementation of RDS to recruit MSM concerning both the importance and limitations of formative work, the need to tailor incentives to circumstances of the less affluent potential participants, the need to prevent masking, and the challenge of assessing network size.

  15. Use of Respondent Driven Sampling (RDS) Generates a Very Diverse Sample of Men Who Have Sex with Men (MSM) in Buenos Aires, Argentina

    PubMed Central

    Carballo-Diéguez, Alex; Balan, Ivan; Marone, Rubén; Pando, María A.; Dolezal, Curtis; Barreda, Victoria; Leu, Cheng-Shiun; Ávila, María Mercedes

    2011-01-01

    Background Prior research focusing on men who have sex with men (MSM) conducted in Buenos Aires, Argentina, used convenience samples that included mainly gay identified men. To increase MSM sample representativeness, we used Respondent Driven Sampling (RDS) for the first time in Argentina. Using RDS, under certain specified conditions, the observed estimates for the percentage of the population with a specific trait are asymptotically unbiased. We describe, the diversity of the recruited sample, from the point of view of sexual orientation, and contrast the different subgroups in terms of their HIV sexual risk behavior. Methodology 500 MSM were recruited using RDS. Behavioral data were collected through face-to-face interviews and Web-based CASI. Conclusion In contrast with prior studies, RDS generated a very diverse sample of MSM from a sexual identity perspective. Only 24.5% of participants identified as gay; 36.2% identified as bisexual, 21.9% as heterosexual, and 17.4% were grouped as “other.” Gay and non-gay identified MSM differed significantly in their sexual behavior, the former having higher numbers of partners, more frequent sexual contacts and less frequency of condom use. One third of the men (gay, 3%; bisexual, 34%, heterosexual, 51%; other, 49%) reported having had sex with men, women and transvestites in the two months prior to the interview. This population requires further study and, potentially, HIV prevention strategies tailored to such diversity of partnerships. Our results highlight the potential effectiveness of using RDS to reach non-gay identified MSM. They also present lessons learned in the implementation of RDS to recruit MSM concerning both the importance and limitations of formative work, the need to tailor incentives to circumstances of the less affluent potential participants, the need to prevent masking, and the challenge of assessing network size. PMID:22102896

  16. [Air pollution and mortality in twenty-five Italian cities: results of the EpiAir2 Project].

    PubMed

    Alessandrini, Ester Rita; Faustini, Annunziata; Chiusolo, Monica; Stafoggia, Massimo; Gandini, Martina; Demaria, Moreno; Antonelli, Antonello; Arena, Pasquale; Biggeri, Annibale; Canova, Cristina; Casale, Giovanna; Cernigliaro, Achille; Garrone, Elsa; Gherardi, Bianca; Gianicolo, Emilio Antonio Luca; Giannini, Simone; Iuzzolino, Claudia; Lauriola, Paolo; Mariottini, Mauro; Pasetto, Paolo; Randi, Giorgia; Ranzi, Andrea; Santoro, Michele; Selle, Vittorio; Serinelli, Maria; Stivanello, Elisa; Tominz, Riccardo; Vigotti, Maria Angela; Zauli-Sajani, Stefano; Forastiere, Francesco; Cadum, Ennio

    2013-01-01

    this study aims at presenting the results from the Italian EpiaAir2 Project on the short-term effects of air pollution on adult population (35+ years old) in 25 Italian cities. the short-term effects of air pollution on resident people died in their city were analysed adopting the time series approach. The association between increases in 10µg/m(3) in PM10, PM2.5, NO2 and O3 air concentration and natural, cardiac, cerebrovascular and respiratory mortality was studied. City-specific Poisson models were fitted to estimate the association of daily concentrations of pollutants with daily counts of deaths. The analysis took into account temporal and meteorological factors to control for potential confounding effect. Pooled estimates have been derived from random effects meta-analysis, evaluating the presence of heterogeneity in the city specific results. it was analysed 422,723 deaths in the 25 cities of the project among people aged 35 years or more, resident in each city during the period 2006-2010. daily counts of natural, cardiac, cerebrovascular, and respiratory mortality, obtained from the registries of each city. Demographic information were obtained by record linkage procedure with the civil registry of each city. mean number of deaths for natural causes ranged from 513 in Rovigo to 20,959 in Rome. About 25% of deaths are due to cardiac diseases, 10% to cerebrovascular diseases, and 7% to respiratory diseases. It was found an immediate effect of PM10 on natural mortality (0.51%; 95%CI 0.16-0.86; lag 0-1). More relevant and prolonged effects (lag 0-5) have been found for PM2.5 (0.78%; 95%CI 0.12-1.46) and NO2 (1.10%; 95%CI 0.63-1.58). Increases in cardiac mortality are associated with PM10 (0.93%; 95%CI 0.16-1.70) and PM2.5 (1.25%; 95%CI 0.17-2.34), while for respiratory mortality exposure to NO2 has an important role (1.67%; 95%CI 0.23-3.13; lag 2-5), as well as PM10 (1.41%; 95%CI - 0.23;+3.08). Results are strongly homogeneous among cities, except for

  17. Relative congener scaling of Polychlorinated dibenzo-p-dioxins and dibenzofurans to estimate building fire contributions in air, surface wipes, and dust samples.

    PubMed

    Pleil, Joachim D; Lorber, Matthew N

    2007-11-01

    The United States Environmental Protection Agency collected ambient air samples in lower Manhattan for about 9 months following the September 11, 2001 World Trade Center (WTC) attacks. Measurements were made of a host of airborne contaminants including volatile organic compounds, polycyclic aromatic hydrocarbons, asbestos, lead, and other contaminants of concern. The present study focuses on the broad class of polychlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) with specific emphasis on the 17 CDD/CDF congeners that exhibit mammalian toxicity. This work is a statistical study comparing the internal patterns of CDD/CDFs using data from an unambiguous fire event (WTC) and other data sets to help identify their sources. A subset of 29 samples all taken between September 16 and October 31, 2001 were treated as a basis set known to be heavily impacted by the WTC building fire source. A second basis set was created using data from Los Angeles and Oakland, CA as published by the California Air Resources Board (CARB) and treated as the archetypical background pattern for CDD/CDFs. The CARB data had a congener profile appearing similar to background air samples from different locations in America and around the world and in different matrices, such as background soils. Such disparate data would normally be interpreted with a qualitative pattern recognition based on congener bar graphs or other forms of factor or cluster analysis that group similar samples together graphically. The procedure developed here employs aspects of those statistical methods to develop a single continuous output variable per sample. Specifically, a form of variance structure-based cluster analysis is used to group congeners within samples to reduce collinearity in the basis sets, new variables are created based on these groups, and multivariate regression is applied to the reduced variable set to determine a predictive equation. This equation predicts a value for an output variable

  18. Urban air quality assessment using monitoring data of fractionized aerosol samples, chemometrics and meteorological conditions.

    PubMed

    Yotova, Galina I; Tsitouridou, Roxani; Tsakovski, Stefan L; Simeonov, Vasil D

    2016-01-01

    The present article deals with assessment of urban air by using monitoring data for 10 different aerosol fractions (0.015-16 μm) collected at a typical urban site in City of Thessaloniki, Greece. The data set was subject to multivariate statistical analysis (cluster analysis and principal components analysis) and, additionally, to HYSPLIT back trajectory modeling in order to assess in a better way the impact of the weather conditions on the pollution sources identified. A specific element of the study is the effort to clarify the role of outliers in the data set. The reason for the appearance of outliers is strongly related to the atmospheric condition on the particular sampling days leading to enhanced concentration of pollutants (secondary emissions, sea sprays, road and soil dust, combustion processes) especially for ultra fine and coarse particles. It is also shown that three major sources affect the urban air quality of the location studied-sea sprays, mineral dust and anthropogenic influences (agricultural activity, combustion processes, and industrial sources). The level of impact is related to certain extent to the aerosol fraction size. The assessment of the meteorological conditions leads to defining of four downwind patterns affecting the air quality (Pelagic, Western and Central Europe, Eastern and Northeastern Europe and Africa and Southern Europe). Thus, the present study offers a complete urban air assessment taking into account the weather conditions, pollution sources and aerosol fractioning.

  19. Evaluation of active sampling strategies for the determination of 1,3-butadiene in air

    NASA Astrophysics Data System (ADS)

    Vallecillos, Laura; Maceira, Alba; Marcé, Rosa Maria; Borrull, Francesc

    2018-03-01

    Two analytical methods for determining levels of 1,3-butadiene in urban and industrial atmospheres were evaluated in this study. Both methods are extensively used for determining the concentration of volatile organic compounds in the atmosphere and involve collecting samples by active adsorptive enrichment on solid sorbents. The first method uses activated charcoal as the sorbent and involves liquid desorption with carbon disulfide. The second involves the use of a multi-sorbent bed with two graphitised carbons and a carbon molecular sieve as the sorbent, with thermal desorption. Special attention was paid to the optimization of the sampling procedure through the study of sample volume, the stability of 1,3-butadiene once inside the sampling tube and the humidity effect. In the end, the thermal desorption method showed better repeatability and limits of detection and quantification for 1,3-butadiene than the liquid desorption method, which makes the thermal desorption method more suitable for analysing air samples from both industrial and urban atmospheres. However, sampling must be performed with a pre-tube filled with a drying agent to prevent the loss of the adsorption capacity of the solid adsorbent caused by water vapour. The thermal desorption method has successfully been applied to determine of 1,3-butadiene inside a 1,3-butadiene production plant and at three locations in the vicinity of the same plant.

  20. Most Recent Sampling Results for Annex III Building

    EPA Pesticide Factsheets

    Contains email from Scott Miller, US EPA to Scott Kramer. Subject: Most Recent Sampling Results for Annex III Building. (2:52 PM) and Gore(TM) Surveys Analytical Results U.S. Geological Survey, Montgomery, AL.

  1. Laser plasma at low air pressure

    NASA Astrophysics Data System (ADS)

    Vas'kovskii, Iu. M.; Moiseev, V. N.; Rovinskii, R. E.; Tsenina, I. S.

    1993-01-01

    The ambient-pressure dependences of the dynamic and optical characteristics of a laser plasma generated by CO2-laser irradiation of an obstacle are investigated experimentally. The change of the sample's surface roughness after irradiation is investigated as a function of air pressure. It is concluded that the transition from the air plasma to the erosion plasma takes place at an air pressure of about 1 mm Hg. The results confirm the existing theory of plasma formation near the surface of an obstacle under the CO2-laser pulse effect in air.

  2. Improved Sampling Method Reduces Isokinetic Sampling Errors.

    ERIC Educational Resources Information Center

    Karels, Gale G.

    The particulate sampling system currently in use by the Bay Area Air Pollution Control District, San Francisco, California is described in this presentation for the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971. The method represents a practical, inexpensive tool that can…

  3. Solar Air Sampler

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Nation's first solar-cell-powered air monitoring station was installed at Liberty State Park, New Jersey. Jointly sponsored by state agencies and the Department of Energy, system includes display which describes its operation to park visitors. Unit samples air every sixth day for a period of 24 hours. Air is forced through a glass filter, then is removed each week for examination by the New Jersey Bureau of Air Pollution. During the day, solar cells provide total power for the sampling equipment. Excess energy is stored in a bank of lead-acid batteries for use when needed.

  4. Transboundary Air Pollution over the Central Himalayas: Monitoring network and Preliminary Results

    NASA Astrophysics Data System (ADS)

    Zhang, Qianggong; Kang, Shichang

    2016-04-01

    The Himalayas, stretching over 3000 kms along west-east, separates South Asia continent and the Tibetan Plateau with its extreme high altitudes. The South Asia is being increasingly recognized to be among the hotspots of air pollution, posing multi-effects on regional climate and environment. Recent monitoring and projection have indicated an accelerated decrease of glacier and increasing glacier runoff in the Himalayas, and a remarkable phenomenon has been recognized in the Himalayas that long-range transport atmospheric pollutants (e.g., black carbon and dust) deposited on glacier surface can promote glacier melt, and in turns, may liberate historical contaminant legacy in glaciers into downward ecosystems. To understand the air pollution variation and how they can infiltrate the Himalayas and beyond, we started to operate a coordinated atmospheric pollution monitoring network composing 11 sites with 5 in Nepal and 6 in Tibet since April 2013. Atmospheric total suspended particles ( TSP < 100 μm) are collected for 24h at an interval of 3-6 days at all sites. Black carbon, typical persistent organic pollutants (PAHs) and heavy metals (particulate-bounded mercury) are measured to reveal their spatial and temporal distributions. Results revealed a consistent gradient decrease in almost all analyzed parameters along south-north gradient across the Himalayas, with a clear seasonal variation of higher values in pre-monsoon seasons. Analysis of geochemical signatures of carbonaceous aerosols indicated dominant sources from biomass burning and vehicle exhaust. PAHs concentrations and signatures from soils and aerosols indicated that low-ring PAHs can readily transport across the Himalayas. Integrated analysis of satellite images and air mass trajectories suggested that the transboundary air pollution over the Himalayas is episodic and is likely concentrated in pre-monsoon seasons. Our results emphasis the potential transport and impact of air pollution from South Asia

  5. Laboratory Development of a Passive Sampling Device for Hydrazines in Ambient Air

    DTIC Science & Technology

    1990-05-30

    of dilution air . Conditioned house- compressed air is used as the diluent. The conditioning procedure consists of passing the house air through a...Device N4 for Hydrazines in Ambient Air P. A. TAFFE,* K. P. CROSSMAN,* S. L. ROSE-PEHRSSON, AND J. R. WYATT 0 Chemistry Dynamics and Diagnostic Branch...Ambient Air 6. AUTHOR(S) Taffe,* P. A., Crossman,* K. P., Wyatt, J. R., and Rose-Pehrsson, S. L. 7. PERFORMING ORGANIZATION NAME(S) AND ADORESS(ES) 8

  6. Air Flow and Pressure Drop Measurements Across Porous Oxides

    NASA Technical Reports Server (NTRS)

    Fox, Dennis S.; Cuy, Michael D.; Werner, Roger A.

    2008-01-01

    This report summarizes the results of air flow tests across eight porous, open cell ceramic oxide samples. During ceramic specimen processing, the porosity was formed using the sacrificial template technique, with two different sizes of polystyrene beads used for the template. The samples were initially supplied with thicknesses ranging from 0.14 to 0.20 in. (0.35 to 0.50 cm) and nonuniform backside morphology (some areas dense, some porous). Samples were therefore ground to a thickness of 0.12 to 0.14 in. (0.30 to 0.35 cm) using dry 120 grit SiC paper. Pressure drop versus air flow is reported. Comparisons of samples with thickness variations are made, as are pressure drop estimates. As the density of the ceramic material increases the maximum corrected flow decreases rapidly. Future sample sets should be supplied with samples of similar thickness and having uniform surface morphology. This would allow a more consistent determination of air flow versus processing parameters and the resulting porosity size and distribution.

  7. Early detection of foot-and-mouth disease virus from infected cattle using a dry filter air sampling system

    USDA-ARS?s Scientific Manuscript database

    Foot-and-mouth disease (FMD) is a highly contagious livestock disease of high economic impact. Early detection of FMD virus (FMDV) is fundamental for rapid outbreak control. Air sampling collection has been demonstrated as a useful technique for detection of FMDV RNA in infected animals, related to ...

  8. Magnesium, Iron and Aluminum in LLNL Air Particulate and Rain Samples with Reference to Magnesium in Industrial Storm Water

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Esser, Bradley K.; Bibby, Richard K.; Fish, Craig

    Storm water runoff from the Lawrence Livermore National Laboratory’s (LLNL’s) main site and Site 300 periodically exceeds the Discharge Permit Numeric Action Level (NAL) for Magnesium (Mg) under the Industrial General Permit (IGP) Order No. 2014-0057-DWQ. Of particular interest is the source of magnesium in storm water runoff from the site. This special study compares new metals data from air particulate and precipitation samples from the LLNL main site and Site 300 to previous metals data for storm water from the main site and Site 300 and alluvial sediment from the main site to investigate the potential source of elevatedmore » Mg in storm water runoff. Data for three metals (Mg, Iron {Fe}, and Aluminum {Al}) were available from all media; data for additional metals, such as Europium (Eu), were available from rain, air particulates, and alluvial sediment. To attribute source, this study compared metals concentration data (for Mg, Al, and Fe) in storm water and rain; metal-metal correlations (Mg with Fe, Mg with Al, Al with Fe, Mg with Eu, Eu with Fe, and Eu with Al) in storm water, rain, air particulates, and sediments; and metal-metal ratios ((Mg/Fe, Mg/Al, Al/Fe, Mg/Eu, Eu/Fe, and Eu/Al) in storm water, rain, air particulates and sediments. The results presented in this study are consistent with a simple conceptual model where the source of Mg in storm water runoff is air particulate matter that has dry-deposited on impervious surfaces and subsequently entrained in runoff during precipitation events. Such a conceptual model is consistent with 1) higher concentrations of metals in storm water runoff than in precipitation, 2) the strong correlation of Mg with Aluminum (Al) and Iron (Fe) in both storm water and air particulates, and 3) the similarity in metal mass ratios between storm water and air particulates in contrast to the dissimilarity of metal mass ratios between storm water and precipitation or alluvial sediment. The strong correlation of Mg with

  9. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF AIR SAMPLES FOR GC/MS ANALYSIS OF PESTICIDES (BCO-L-11.0)

    EPA Science Inventory

    The purpose of this SOP is to describe the procedures for extracting and preparing an air sample consisting of a polyurethane foam (PUF) plug and Teflon-coated glass fiber filter (Pallflex T60A20) for analysis of pesticides. This procedure covers sample preparation for samples t...

  10. Assessment of Air Quality in the Shuttle and International Space Station (ISS) Based on Samples Returned by STS-100 at the Conclusion of 6A

    NASA Technical Reports Server (NTRS)

    James, John T.

    2001-01-01

    The toxicological assessment of air samples returned at the end of the STS-100 (6A) flight to the ISS is reported. ISS air samples were taken in March and April 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges. An unplanned "first-entry" sample of the MPLM2 (multipurpose logistics module) atmosphere was taken with a GSC, and preflight and end-of-mission samples were obtained from Endeavour using GSCs. Analytical methods have not changed from earlier reports, and all quality control measures were met for the data presented herein. The two general criteria used to assess air quality are the total-non-methane-volatile organic hydrocarbons (NMVOCs) and the total T-value (minus the CO2 and formaldehyde contribution). Because of the Freon 218 (octafluoropropane, OFP) leak, its contribution to the NMVOC is indicated in brackets. When comparing the NMVOC values with the 25 mg/cubic m guideline, the OFP contributions should be subtracted. Control of atmospheric alcohols is important to the water recovery system engineers, hence total alcohols were also assessed in each sample.

  11. A 2-year comparative study of mold and bacterial counts in air samples from neutral and positive pressure rooms in 2 tertiary care hospitals.

    PubMed

    Ryan, Laura; O'Mara, Niall; Tansey, Sana; Slattery, Tom; Hanahoe, Belinda; Vellinga, Akke; Doyle, Maeve; Cormican, Martin

    2018-05-01

    Immunocompromised patients are at risk of invasive fungal infection. These high-risk patients are nursed in protective isolation to reduce the risk of nosocomial aspergillosis while in hospital-ideally in a positive pressure single room with high-efficiency particulate air filtration. However, neutral pressure rooms are a potential alternative, especially for patients requiring both protective and source isolation. This study examined mold and bacterial concentrations in air samples from positive and neutral pressure rooms to assess whether neutral pressure rooms offer a similar environment to that of positive pressure rooms in terms of mold concentrations in the air. Mold concentrations were found to be similar in the positive and neutral pressure room types examined in this study. These results add to the paucity of literature in this area. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  12. Infrequent air contamination with Acinetobacter baumannii of air surrounding known colonized or infected patients.

    PubMed

    Rock, Clare; Harris, Anthony D; Johnson, J Kristie; Bischoff, Werner E; Thom, Kerri A

    2015-07-01

    Using a validated air sampling method we found Acinetobacter baumannii in the air surrounding only 1 of 12 patients known to be colonized or infected with A. baumannii. Patients' closed-circuit ventilator status, frequent air exchanges in patient rooms, and short sampling time may have contributed to this low burden.

  13. Operating theatre ventilation systems and microbial air contamination in total joint replacement surgery: results of the GISIO-ISChIA study.

    PubMed

    Agodi, A; Auxilia, F; Barchitta, M; Cristina, M L; D'Alessandro, D; Mura, I; Nobile, M; Pasquarella, C

    2015-07-01

    Recent studies have shown a higher rate of surgical site infections in hip prosthesis implantation using unidirectional airflow ventilation compared with turbulent ventilation. However, these studies did not measure the air microbial quality of operating theatres (OTs), and assumed it to be compliant with the recommended standards for this ventilation technique. To evaluate airborne microbial contamination in OTs during hip and knee replacement surgery, and compare the findings with values recommended for joint replacement surgery. Air samplings were performed in 28 OTs supplied with unidirectional, turbulent and mixed airflow ventilation. Samples were collected using passive sampling to determine the index of microbial air contamination (IMA). Active sampling was also performed in some of the OTs. The average number of people in the OT and the number of door openings during the sampling period were recorded. In total, 1228 elective prosthesis procedures (60.1% hip and 39.9% knee) were included in this study. Of passive samplings performed during surgical activity in unidirectional airflow ventilation OTs (U-OTs) and mixed airflow OTs (M-OTs), 58.9% and 87.6% had IMA values >2, respectively. Of samplings performed during surgical activity in turbulent airflow OTs (T-OTs) and in turbulent airflow OTs with the surgical team wearing Steri-Shield Turbo Helmets (TH-OTs), 8.6% and 60% had IMA values ≤ 2, respectively. Positive correlation was found between IMA values and the number of people in the OT and the number of door openings (P < 0.001). In addition, correlation was found between active and passive sampling (P < 0.001). These findings challenge the belief that unidirectional systems always provide acceptable airborne bacterial counts. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  14. Radiological Air Sampling. Protocol Development for the Canadian Forces

    DTIC Science & Technology

    2003-03-01

    samplers trap these airborne radon daughters . Because radon is ubiquitous, all air samplers will catch these radioactive radon daughters in the...environment is complicated because all air sampler filters are radioactive because of the radon daughters . ’Actually, D will often depend on the isotope that...simply as "radon". 2 DRDC Ottawa TM 2003-149 -28 - 22 R_ 211p0 214pb 3.8 d 3.0 m 27 m 214Bi 210TI Radon Daughters 20 m ŕ.3 m (Uranium Decay Chain

  15. Biomimetic air sampling for detection of low concentrations of molecules and bioagents : LDRD 52744 final report.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hughes, Robert Clark

    2003-12-01

    Present methods of air sampling for low concentrations of chemicals like explosives and bioagents involve noisy and power hungry collectors with mechanical parts for moving large volumes of air. However there are biological systems that are capable of detecting very low concentrations of molecules with no mechanical moving parts. An example is the silkworm moth antenna which is a highly branched structure where each of 100 branches contains about 200 sensory 'hairs' which have dimensions of 2 microns wide by 100 microns long. The hairs contain about 3000 pores which is where the gas phase molecules enter the aqueous (lymph)more » phase for detection. Simulations of diffusion of molecules indicate that this 'forest' of hairs is 'designed' to maximize the extraction of the vapor phase molecules. Since typical molecules lose about 4 decades in diffusion constant upon entering the liquid phase, it is important to allow air diffusion to bring the molecule as close to the 'sensor' as possible. The moth acts on concentrations as low as 1000 molecules per cubic cm. (one part in 1e16). A 3-D collection system of these dimensions could be fabricated by micromachining techniques available at Sandia. This LDRD addresses the issues involved with extracting molecules from air onto micromachined structures and then delivering those molecules to microsensors for detection.« less

  16. Evaluation of sample recovery of malodorous livestock gases from air sampling bags, solid-phase microextraction fibers, Tenax TA sorbent tubes, and sampling canisters.

    PubMed

    Koziel, Jacek A; Spinhirne, Jarett P; Lloyd, Jenny D; Parker, David B; Wright, Donald W; Kuhrt, Fred W

    2005-08-01

    Odorous gases associated with livestock operations are complex mixtures of hundreds if not thousands of compounds. Research is needed to know how best to sample and analyze these compounds. The main objective of this research was to compare recoveries of a standard gas mixture of 11 odorous compounds from the Carboxen/PDMS 75-microm solid-phase microextraction fibers, polyvinyl fluoride (PVF; Tedlar), fluorinated ethylene propylene copolymer (FEP; Teflon), foil, and polyethylene terephthalate (PET; Melinex) air sampling bags, sorbent 2,b-diphenylene-oxide polymer resin (Tenax TA) tubes, and standard 6-L Stabilizer sampling canisters after sample storage for 0.5, 24, and 120 (for sorbent tubes only) hrs at room temperature. The standard gas mixture consisted of 7 volatile fatty acids (VFAs) from acetic to hexanoic, and 4 semivolatile organic compounds including p-cresol, indole, 4-ethylphenol, and 2'-aminoacetophenone with concentrations ranging from 5.1 ppb for indole to 1270 ppb for acetic acid. On average, SPME had the highest mean recovery for all 11 gases of 106.2%, and 98.3% for 0.5- and 24-hr sample storage time, respectively. This was followed by the Tenax TA sorbent tubes (94.8% and 88.3%) for 24 and 120 hr, respectively; PET bags (71.7% and 47.2%), FEP bags (75.4% and 39.4%), commercial Tedlar bags (67.6% and 22.7%), in-house-made Tedlar bags (47.3% and 37.4%), foil bags (16.4% and 4.3%), and canisters (4.2% and 0.5%), for 0.5 and 24 hr, respectively. VFAs had higher recoveries than semivolatile organic compounds for all of the bags and canisters. New FEP bags and new foil bags had the lowest and the highest amounts of chemical impurities, respectively. New commercial Tedlar bags had measurable concentrations of N,N-dimethyl acetamide and phenol. Foil bags had measurable concentrations of acetic, propionic, butyric, valeric, and hexanoic acids.

  17. Indoor air quality investigation and health risk assessment at correctional institutions.

    PubMed

    Ofungwu, Joseph

    2005-04-01

    A comprehensive indoor air-quality (IAQ) investigation was conducted at a state correctional facility in New Jersey, USA with a lengthy history of IAQ problems. The IAQ investigation comprised preliminary indoor air screening using direct readout instrumentation, indoor air/surface wipe sampling and laboratory analysis, as well as a heating, ventilation, and air-conditioning system evaluation, and a building envelope survey. In addition to air sampling, a human health risk assessment was performed to evaluate the potential for exposure to site-related air contaminants with respect to the inmate and worker populations. The risk assessment results for the prison facility indicated the potential for significant health risks for the inmate population, possibly reflecting the effects of their confinement and extended exposure to indoor air contaminants, as compared to the prison guard and worker population. Based on the results of the risk assessment, several mitigation measures are recommended to minimize prison population health risks and improve indoor air quality at prison facilities.

  18. HESTIA Phase I Test Results: The Air Revitalization System

    NASA Technical Reports Server (NTRS)

    Wright, Sarah E.; Hansen, Scott W.

    2016-01-01

    In any human spaceflight mission, a number of Environmental Control & Life Support System (ECLSS) technologies work together to provide the conditions astronauts need to live healthily, productively, and comfortably in space. In a long-duration mission, many of these ECLSS technologies may use materials supplied by In-Situ Resource Utilization (ISRU), introducing more interactions between systems. The Human Exploration Spacecraft Test-bed for Integration & Advancement (HESTIA) Project aims to create a test-bed to evaluate ECLSS and ISRU technologies and how they interact in a high-fidelity, closed-loop, human-rated analog habitat. Air purity and conditioning are essential components within any ECLSS and for HESTIA's first test they were achieved with the Air Revitalization System (ARS) described below. The ARS provided four essential functions to the test-bed chamber: cooling the air, removing humidity from the air, removing trace contaminants, and scrubbing carbon dioxide (CO2) from the air. In this case, the oxygen supply function was provided by ISRU. In the current configuration, the ARS is a collection of different subsystems. A fan circulates the air, while a condensing heat exchanger (CHX) pulls humidity out of the air. A Trace Contaminant Removal System (TCRS) filters the air of potentially harmful contaminants. Lastly, a Reactive Plastic Lithium Hydroxide (RP-LiOH) unit removes CO2 from the breathing air. During the HESTIA Phase I test in September 2015, the ARS and its individual components each functioned as expected, although further analysis is underway. During the Phase I testing and in prior bench-top tests, the energy balance of heat removed by the CHX was not equal to the cooling it received. This indicated possible instrument error and therefore recalibration of the instruments and follow-up testing is planned in 2016 to address the issue. The ARS was tested in conjunction with two other systems: the Human Metabolic Simulator (HMS) and the

  19. Solid-phase microextraction fiber development for sampling and analysis of volatile organohalogen compounds in air.

    PubMed

    Attari, Seyed Ghavameddin; Bahrami, Abdolrahman; Shahna, Farshid Ghorbani; Heidari, Mahmoud

    2014-01-01

    A green, environmental friendly and sensitive method for determination of volatile organohalogen compounds was described in this paper. The method is based on a homemade sol-gel single-walled carbon nanotube/silica composite coated solid-phase microextraction to develop for sampling and analysis of Carbon tetrachloride, Benzotrichloride, Chloromethyl methyl ether and Trichloroethylene in air. Application of this method was investigated under different laboratory conditions. Predetermined concentrations of each analytes were prepared in a home-made standard chamber and the influences of experimental parameters such as temperature, humidity, extraction time, storage time, desorption temperature, desorption time and the sorbent performance were investigated. Under optimal conditions, the use of single-walled carbon nanotube/silica composite fiber showed good performance, high sensitive and fast sampling of volatile organohalogen compounds from air. For linearity test the regression correlation coefficient was more than 98% for analyte of interest and linear dynamic range for the proposed fiber and the applied Gas Chromatography-Flame Ionization Detector technique was from 1 to 100 ngmL(-1). Method detection limits ranged between 0.09 to 0.2 ngmL(-1) and method quantification limits were between 0.25 and 0.7 ngmL(-1). Single-walled carbon nanotube/silica composite fiber was highly reproducible, relative standard deviations were between 4.3 to 11.7 percent.

  20. Atmospheric Carbon Monoxide Mixing Ratios NOAA Climate Monitoring and Diagnostics Laboratory Cooperative Air Sampling Network (1988-1993) (DB1011)

    DOE Data Explorer

    Novelli, P. C.; Masarie, K. A.

    1994-01-01

    Individual site files provide CO mixing ratios in parts per billion (ppb) (ppb = parts in 109 by mole fraction) based on measurements from the NOAA/CMDL Cooperative Air Sampling Network beginning 1988. Data are provided through June 1993 for stations at which the first sample was collected before July 1991. All samples were analyzed for CO at the NOAA/CMDL laboratory in Boulder by gas chromatography with mercuric oxide reduction detection, and all measurements are referenced to the CMDL CO scale (Novelli et al., 1991, Novelli et al., 1994).

  1. Environmental sampling and analysis in support of NTI-3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McGuire, R.R.; Harrar, J.E.; Haas, J.S.

    1991-04-06

    The third National Trail Inspection took place at the Monsanto Chemical Plant in Luling, Louisiana. In order to test the effectiveness of environmental sampling (soil, water and air) in determining the nature of the chemical process in a given production plant and to examine the distance from a process building that samples can effectively be taken, we needed to select some materials that constituted components of process streams. Three materials were selected: 1. isopropyl amine for air monitoring, 2. 4-nitrophenol, one of the precursors in the acetaminophen process, and 3. an intermediate in the production of glyphosate for ROUNDUP thatmore » is known simply as glyphosate intermediated. LLNL did not participate in the air sampling nor the analysis for isopropyl amine. This paper discussed the steps in this experiment including sample collection, sample workshop, sample analysis the results and discussion and the conclusion. 3 figs., 6 tabs.« less

  2. Performances and application of a passive sampling method for the simultaneous determination of nitrogen dioxide and sulfur dioxide in ambient air.

    PubMed

    Plaisance, H; Sagnier, I; Saison, J Y; Galloo, J C; Guillermo, R

    2002-11-01

    The performances and applicability of a diffusion tube sampler for the simultaneous measurements of NO2 and SO2 in ambient air were evaluated. SO2 and NO2 are collected by the passive sampler using triethanolamine as trapping agent and are determined as sulphate and nitrite with ion chromatography. The detection limit (2.3 microg m(-3) of NO2 and 4.2 microg m(-3) of SO2 for two weeks sampling) is adequate for the determination of concentrations in urban and industrial areas. Precision of the method as RSD is in mean 5% for NO2 and 12% for SO2 at the concentration levels in urban areas. Calibration of the method was performed in the field conditions by comparison between the responses of sampler and the concentrations measured by the continuous monitors. High degree of linearity (correlation coefficients > 0.8) is found between the passive sampler tube and the continuous monitor data for both NO2 and SO2. To reduce the wind velocity influence on passive sampling of diffusion tubes, a protective shelter was tested in this study. The overall uncertainty of one measure for the optimised method is estimated at 5 microg m(-3) for NO2 and 6 microg m(-3) for SO2. Suitability of this passive sampling method for air pollution monitoring in urban areas was demonstrated by the results shown in this paper on a campaign carried out in the French agglomeration.

  3. Odour-causing compounds in air samples: gas-liquid partition coefficients and determination using solid-phase microextraction and GC with mass spectrometric detection.

    PubMed

    Godayol, Anna; Alonso, Mònica; Sanchez, Juan M; Anticó, Enriqueta

    2013-03-01

    A quantification method based on solid-phase microextraction followed by GC coupled to MS was developed for the determination of gas-liquid partition coefficients and for the air monitoring of a group of odour-causing compounds that had previously been found in wastewater samples including dimethyl disulphide, phenol, indole, skatole, octanal, nonanal, benzothiazole and some terpenes. Using a divinylbenzene/carboxen/polydimethylsiloxane fibre, adsorption kinetics have been studied to define an extraction time that would avoid coating saturation. It was found that for an extraction time of 10 min, external calibration could be performed in the range of 0.4-100 μg/m(3), with detection limits between 0.1 and 20 μg/m(3). Inter-day precision of the developed method was evaluated (n = 5) and RSD values between 12 and 24% were obtained for all compounds. The proposed method has been applied to the analysis of air samples surrounding a wastewater treatment plant in Catalonia (Spain). In all air samples evaluated, dimethyl disulphide, limonene and phenol were detected, and the first two were the compounds that showed the highest partition coefficients. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Characterization of the bacterial and fungal microbiome in indoor dust and outdoor air samples: a pilot study.

    PubMed

    Hanson, Blake; Zhou, Yanjiao; Bautista, Eddy J; Urch, Bruce; Speck, Mary; Silverman, Frances; Muilenberg, Michael; Phipatanakul, Wanda; Weinstock, George; Sodergren, Erica; Gold, Diane R; Sordillo, Joanne E

    2016-06-15

    Environmental microbes have been associated with both protective and adverse health effects in children and adults. Epidemiological studies often rely on broad biomarkers of microbial exposure (i.e. endotoxin, 1 → 3-beta-d-glucan), but fail to identify the taxonomic composition of the microbial community. Our aim was to characterize the bacterial and fungal microbiome in different types of environmental samples collected in studies of human health effects. We determined the composition of microbial communities present in home, school and outdoor air samples by amplifying and sequencing regions of rRNA genes from bacteria (16S) and fungi (18S and ITS). Samples for this pilot study included indoor settled dust (from both a Boston area birth cohort study on Home Allergens and Asthma (HAA) (n = 12) and a study of school exposures and asthma symptoms (SICAS) (n = 1)), as well as fine and coarse concentrated outdoor ambient particulate (CAP) samples (n = 9). Sequencing of amplified 16S, 18S, and ITS regions was performed on the Roche-454 Life Sciences Titanium pyrosequencing platform. Indoor dust samples were dominated by Gram-positive bacteria (Firmicutes and Actinobacteria); the most abundant bacterial genera were those related to human flora (Streptococcus, Staphylococcus, Corynebacterium and Lactobacillus). Outdoor CAPs were dominated by Gram-negative Proteobacteria from water and soil sources, in particular the genera Acidovorax, and Brevundimonas (which were present at very low levels or entirely absent in indoor dust). Phylum-level fungal distributions identified by 18S or ITS regions showed very similar findings: a predominance of Ascomycota in indoor dust and Basidiomycota in outdoor CAPs. ITS sequencing of fungal genera in indoor dust showed significant proportions of Aureobasidium and Leptosphaerulina along with some contribution from Cryptococcus, Epicoccum, Aspergillus and the human commensal Malassezia. ITS sequencing detected more than 70 fungal genera

  5. Reliability of air displacement plethysmography in a large, heterogeneous sample.

    PubMed

    Noreen, Eric E; Lemon, Peter W R

    2006-08-01

    Several studies have assessed the validity of air displacement plethysmography (ADP), but few have assessed the reliability of ADP using a large, heterogeneous sample. This study was conducted to determine the reliability of ADP using the Bod Pod in a large, heterogeneous sample. A total of 980 healthy men and women (30 +/- 15 yr, mean +/- SD) completed two body composition assessments separated by 15-30 min. All testing was done in accordance with the manufacturer's instructions. A significant correlation (r = 0.992, P = 0.001) was found between body density (BD) 1 (1.046 +/- 0.001 kg.L(-1); mean +/- SEM) and BD 2 (1.046 +/- 0.001 kg.L(-1). A paired t-test revealed no significant difference between BD 1 and 2 (P = 0.935). The coefficient of variation (CV) for BD was 0.15%. A significant intraclass correlation coefficient (ICC) was found for BD (ICC = 0.996, P = 0.001), and the standard error of measurement (SEM) was 0.001 kg.L(-1). Body mass (BM) 1 and 2 were correlated significantly (r = 0.999, P = 0.001); however, a significant (P = 0.001) decrease was seen from BM 1 (75.510 +/- 0.461 kg) to BM 2 (75.497 +/- 0.461 kg). Body volume (BV) tended to decrease (P = 0.08) from BV 1 (69.900 +/- 0.449 L) to BV 2 (69.884 +/- 0.449 L). ADP using the Bod Pod appears to assess BD reliably; however, the observed CV suggests that multiple trials are necessary to detect small treatment effects.

  6. Validation of the Hirst-Type Spore Trap for Simultaneous Monitoring of Prokaryotic and Eukaryotic Biodiversities in Urban Air Samples by Next-Generation Sequencing.

    PubMed

    Núñez, Andrés; Amo de Paz, Guillermo; Ferencova, Zuzana; Rastrojo, Alberto; Guantes, Raúl; García, Ana M; Alcamí, Antonio; Gutiérrez-Bustillo, A Montserrat; Moreno, Diego A

    2017-07-01

    Pollen, fungi, and bacteria are the main microscopic biological entities present in outdoor air, causing allergy symptoms and disease transmission and having a significant role in atmosphere dynamics. Despite their relevance, a method for monitoring simultaneously these biological particles in metropolitan environments has not yet been developed. Here, we assessed the use of the Hirst-type spore trap to characterize the global airborne biota by high-throughput DNA sequencing, selecting regions of the 16S rRNA gene and internal transcribed spacer for the taxonomic assignment. We showed that aerobiological communities are well represented by this approach. The operational taxonomic units (OTUs) of two traps working synchronically compiled >87% of the total relative abundance for bacterial diversity collected in each sampler, >89% for fungi, and >97% for pollen. We found a good correspondence between traditional characterization by microscopy and genetic identification, obtaining more-accurate taxonomic assignments and detecting a greater diversity using the latter. We also demonstrated that DNA sequencing accurately detects differences in biodiversity between samples. We concluded that high-throughput DNA sequencing applied to aerobiological samples obtained with Hirst spore traps provides reliable results and can be easily implemented for monitoring prokaryotic and eukaryotic entities present in the air of urban areas. IMPORTANCE Detection, monitoring, and characterization of the wide diversity of biological entities present in the air are difficult tasks that require time and expertise in different disciplines. We have evaluated the use of the Hirst spore trap (an instrument broadly employed in aerobiological studies) to detect and identify these organisms by DNA-based analyses. Our results showed a consistent collection of DNA and a good concordance with traditional methods for identification, suggesting that these devices can be used as a tool for continuous

  7. Validation of the Hirst-Type Spore Trap for Simultaneous Monitoring of Prokaryotic and Eukaryotic Biodiversities in Urban Air Samples by Next-Generation Sequencing

    PubMed Central

    Núñez, Andrés; Amo de Paz, Guillermo; Ferencova, Zuzana; Rastrojo, Alberto; Guantes, Raúl; García, Ana M.; Alcamí, Antonio; Gutiérrez-Bustillo, A. Montserrat

    2017-01-01

    ABSTRACT Pollen, fungi, and bacteria are the main microscopic biological entities present in outdoor air, causing allergy symptoms and disease transmission and having a significant role in atmosphere dynamics. Despite their relevance, a method for monitoring simultaneously these biological particles in metropolitan environments has not yet been developed. Here, we assessed the use of the Hirst-type spore trap to characterize the global airborne biota by high-throughput DNA sequencing, selecting regions of the 16S rRNA gene and internal transcribed spacer for the taxonomic assignment. We showed that aerobiological communities are well represented by this approach. The operational taxonomic units (OTUs) of two traps working synchronically compiled >87% of the total relative abundance for bacterial diversity collected in each sampler, >89% for fungi, and >97% for pollen. We found a good correspondence between traditional characterization by microscopy and genetic identification, obtaining more-accurate taxonomic assignments and detecting a greater diversity using the latter. We also demonstrated that DNA sequencing accurately detects differences in biodiversity between samples. We concluded that high-throughput DNA sequencing applied to aerobiological samples obtained with Hirst spore traps provides reliable results and can be easily implemented for monitoring prokaryotic and eukaryotic entities present in the air of urban areas. IMPORTANCE Detection, monitoring, and characterization of the wide diversity of biological entities present in the air are difficult tasks that require time and expertise in different disciplines. We have evaluated the use of the Hirst spore trap (an instrument broadly employed in aerobiological studies) to detect and identify these organisms by DNA-based analyses. Our results showed a consistent collection of DNA and a good concordance with traditional methods for identification, suggesting that these devices can be used as a tool for

  8. Circumventing shallow air contamination in Mid Ocean Ridge Basalts

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Sujoy; Parai, Rita; Tucker, Jonathan; Middleton, Jennifer; Langmuir, Charles

    2016-04-01

    Noble gases in mantle-derived basalts provide a rich portrait of mantle degassing and surface-interior volatile exchange. However, the ubiquity of shallow-level air contamination frequently obscures the mantle noble gas signal. In a majority of samples, shallow air contamination dominates the noble gas budget. As a result, reconstructing the variability in heavy noble gas mantle source compositions and inferring the history of deep recycling of atmospheric noble gases is difficult. For example, in the gas-rich popping rock 2ΠD43, 129Xe/130Xe ratios reach 7.7±0.23 in individual step-crushes, but the bulk composition of the sample is close to air (129Xe/130Xe of 6.7). Here, we present results from experiments designed to elucidate the source of shallow air contamination in MORBs. Step-crushes were carried out to measure He, Ne, Ar and Xe isotopic compositions on two aliquots of a depleted popping glass that was dredged from between the Kane and Atlantis Fracture Zones of the Mid-Atlantic Ridge in May 2012. One aliquot was sealed in ultrapure N2 after dredge retrieval, while the other aliquot was left exposed to air for 3.5 years. The bulk 20Ne/22Ne and 129Xe/130Xe ratios measured in the aliquot bottled in ultrapure N2 are 12.3 and 7.6, respectively, and are nearly identical to the estimated mantle source values. On the other hand, step crushes in the aliquot left exposed to air for several years show Ne isotopic compositions that are shifted towards air, with a bulk 20Ne/22Ne of 11.5; the bulk 129Xe/130Xe, however, was close to 7.6. These results indicate that lighter noble gases exchange more efficiently between the bubbles trapped in basalt glass and air, suggesting a diffusive or kinetic mechanism for the incorporation of the shallow air contamination. Importantly, in Ne-Ar or Ar-Xe space, step-crushes from the bottled aliquot display a trend that can be easily fit with a simple two-component hyperbolic mixing between mantle and atmosphere noble gases. Step

  9. Recent select Sample Analysis at Mars (SAM) Testbed analog results

    NASA Astrophysics Data System (ADS)

    Malespin, C.; McAdam, A.; Teinturier, S.; Eigenbrode, J. L.; Freissinet, C.; Knudson, C. A.; Lewis, J. M.; Millan, M.; Steele, A.; Stern, J. C.; Williams, A. J.

    2017-12-01

    The Sample Analysis at Mars (SAM) testbed (TB) is a high fidelity replica of the flight instrument currently onboard the Curiosity rover in Gale Crater, Mars1. The SAM testbed is housed in a Mars environment chamber at NASA Goddard Space Flight Center (GSFC), which can replicate both thermal and environmental conditions. The testbed is used to validate and test new experimental procedures before they are implemented on Mars, but it is also used to analyze analog samples which assists in the interpretation of results from the surface. Samples are heated using the same experimental protocol as on Mars to allow for direct comparison with Martian sampling conditions. Here we report preliminary results from select samples that were loaded into the SAM TB, including meteorites, an organically rich iron oxide, and a synthetic analog to the Martian Cumberland sample drilled by the rover at Yellowknife Bay. Each of these samples have been analyzed under SAM-like conditions using breadboard and lab instrument systems. By comparing the data from the lab systems and SAM TB, further insight on results from Mars can be gained. References: [1] Mahaffy, P. R., et al. (2013), Science, 341(6143), 263-266, doi:10.1126/science.1237966.

  10. Adventures in the Environmental World and Environmental Microbiology Sampling of Air for Pharmaceutical Sterile Compounding.

    PubMed

    Ligugnana, Roberto

    2017-01-01

    Chapter <797> issued by the United States Pharmacopeial Convention, Inc. is the standard for sterile compounding. It is designed to reduce the number of patient infections due to contaminated pharmaceutical preparation. This regulation applies to all staff who prepare compounded sterile preparations and all places where they are produced, including hospitals, clinics, pharmacies, and physician's offices. This article provides the history of environmental microbiology and provides a discussion on environmental microbiology sampling of air for pharmaceutical sterile compounding. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

  11. Results from CrIS-ATMS Obtained Using the AIRS Science Team Retrieval Methodology

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Kouvaris, Louis C.; Iredell, Lena

    2013-01-01

    which significantly improved results of AIRS Version-6. Version-5.70 CrIS/ATMS temperature profile and surface skin temperature retrievals are of very good quality, and are better than AIRS Version-5 retrievals, but are still significantly poorer than those of AIRS Version-6. CrIS/ATMS retrievals should improve when a Neural-Net start-up system is ready for use. We also examined CrIS/ATMS retrievals generated by NOAA using their NUCAPS retrieval algorithm, which is based on earlier versions of the AIRS Science Team retrieval algorithms. We show that the NUCAPS algorithm as currently configured is not well suited for climate monitoring purposes.

  12. Measurements of concentrations of chlorofluoromethanes (CFMs) carbon dioxide and carbon isotope ratio in stratospheric and tropospheric air by grab-sampling systems

    NASA Technical Reports Server (NTRS)

    Itoh, T.; Kubo, H.; Honda, H.; Tominaga, T.; Makide, Y.; Yakohata, A.; Sakai, H.

    1985-01-01

    Measurements of concentrations of chlorofluoromethanes (CFMs), carbon dioxide and carbon isotope ratio in stratospheric and tropospheric air by grab-sampling systems are reported. The balloon-borne grab-sampling system has been launched from Sanriku Balloon Center three times since 1981. It consists of: (1) six sampling cylinders, (2) eight motor driven values, (3) control and monitor circuits, and (4) pressurized housing. Particular consideration is paid to the problem of contamination. Strict requirements are placed on the choice of materials and components, construction methods, cleaning techniques, vacuum integrity, and sampling procedures. An aluminum pressurized housing and a 4-m long inlet line are employed to prevent the sampling air from contamination by outgassing of sampling and control devices. The sampling is performed during the descent of the system. Vertical profiles of mixing ratios of CF2Cl2, CFCl3 and CH4 are given. Mixing ratios of CF2Cl2 and CFCl3 in the stratosphere do not show the discernible effect of the increase of those in the ground level background, and decrease with altitude. Decreasing rate of CFCl3 is larger than that of CF2Cl2. CH4 mixing ratio, on the other hand, shows diffusive equilibrium, as the photodissociation cross section of CH4 is small and concentrations of OH radical and 0(sup I D) are low.

  13. The measurement of carbon monoxide and methane in the national capital air quality control region. III - Correlation interferometer results

    NASA Technical Reports Server (NTRS)

    Goldstein, H. W.; Bortner, M. H.; Grenda, R. N.; Dick, R.; Lebel, P. J.; Lamontagne, R. A.

    1976-01-01

    Two types of experiments were performed with a correlation interferometer on-board a Bell Jet Ranger 206 Helicopter. The first consisted of simultaneous ground- and air-truth measurements as the instrumented helicopter passed over the Cheverly site. The second consisted of several measurement flights in and around the national capital air quality control region (Washington, D.C.). The correlation interferometer data, the infrared Fourier spectrometer data, and the integrated altitude sampling data showed agreement within the errors of the individual measurements. High values for CO were found from the D.C. flight data to be reproducible and concentrated in areas of stop-and-go traffic. It is concluded, that pollutants at low altitudes are detectable from an air-borne platform by remote correlation interferometry and that the correlation interferometer measurements agree with ground- and air-truth data.

  14. Pesticides in Mississippi air and rain: a comparison between 1995 and 2007.

    PubMed

    Majewski, Michael S; Coupe, Richard H; Foreman, William T; Capel, Paul D

    2014-06-01

    A variety of current-use pesticides were determined in weekly composite air and rain samples collected during the 1995 and 2007 growing seasons in the Mississippi Delta (MS, USA) agricultural region. Similar sampling and analytical methods allowed for direct comparison of results. Decreased overall pesticide use in 2007 relative to 1995 generally resulted in decreased detection frequencies in air and rain; observed concentration ranges were similar between years, however, even though the 1995 sampling site was 500 m from active fields whereas the 2007 sampling site was within 3 m of a field. Mean concentrations of detections were sometimes greater in 2007 than in 1995, but the median values were often lower. Seven compounds in 1995 and 5 in 2007 were detected in ≥50% of both air and rain samples. Atrazine, metolachlor, and propanil were detected in ≥50% of the air and rain samples in both years. Glyphosate and its degradation product, aminomethyl-phosphonic acid (AMPA), were detected in ≥75% of air and rain samples in 2007 but were not measured in 1995. The 1995 seasonal wet depositional flux was dominated by methyl parathion (88%) and was >4.5 times the 2007 flux. Total herbicide flux in 2007 was slightly greater than in 1995 and was dominated by glyphosate. Malathion, methyl parathion, and degradation products made up most of the 2007 nonherbicide flux. © 2014 SETAC.

  15. Pesticides in Mississippi air and rain: A comparison between 1995 and 2007

    USGS Publications Warehouse

    Majewski, Michael S; Coupe, Richard H.; Foreman, William T.; Capel, Paul D.

    2014-01-01

    A variety of current-use pesticides were determined in weekly composite air and rain samples collected during the 1995 and 2007 growing seasons in the Mississippi Delta (MS, USA) agricultural region. Similar sampling and analytical methods allowed for direct comparison of results. Decreased overall pesticide use in 2007 relative to 1995 generally resulted in decreased detection frequencies in air and rain; observed concentration ranges were similar between years, however, even though the 1995 sampling site was 500 m from active fields whereas the 2007 sampling site was within 3 m of a field. Mean concentrations of detections were sometimes greater in 2007 than in 1995, but the median values were often lower. Seven compounds in 1995 and 5 in 2007 were detected in ≥50% of both air and rain samples. Atrazine, metolachlor, and propanil were detected in ≥50% of the air and rain samples in both years. Glyphosate and its degradation product, aminomethyl-phosphonic acid (AMPA), were detected in ≥75% of air and rain samples in 2007 but were not measured in 1995. The 1995 seasonal wet depositional flux was dominated by methyl parathion (88%) and was >4.5 times the 2007 flux. Total herbicide flux in 2007 was slightly greater than in 1995 and was dominated by glyphosate. Malathion, methyl parathion, and degradation products made up most of the 2007 nonherbicide flux.

  16. Alpha-environmental continuous air monitor inlet

    DOEpatents

    Rodgers, John C.

    2003-01-01

    A wind deceleration and protective shroud that provides representative samples of ambient aerosols to an environmental continuous air monitor (ECAM) has a cylindrical enclosure mounted to an input on the continuous air monitor, the cylindrical enclosure having shrouded nozzles located radially about its periphery. Ambient air flows, often along with rainwater flows into the nozzles in a sampling flow generated by a pump in the continuous air monitor. The sampling flow of air creates a cyclonic flow in the enclosure that flows up through the cylindrical enclosure until the flow of air reaches the top of the cylindrical enclosure and then is directed downward to the continuous air monitor. A sloped platform located inside the cylindrical enclosure supports the nozzles and causes any moisture entering through the nozzle to drain out through the nozzles.

  17. Quantifying India's HFC emissions from whole-air samples collected on the UK-India Monsoon campaign

    NASA Astrophysics Data System (ADS)

    Say, Daniel; Ganesan, Anita; O'Doherty, Simon; Bauguitte, Stephane; Rigby, Matt; Lunt, Mark

    2017-04-01

    With a population exceeding 1 billion and a rapidly expanding economy, greenhouse gas (GHG) emissions from India are of global significance. As of 2010, India's anthropogenic GHG emissions accounted for 5.6% of the global total, with this share predicted to grow significantly in the coming decades. We focus here on hydrofluorocarbons (HFCs), a diverse range of potent GHGs, whose role as replacements for ozone-depleting CFCs and HCFCs in air-conditioning and refrigeration applications (among others) has led to rapid atmospheric accumulation. Recent efforts to reduce their consumption (and subsequent emission) culminated in an amendment to the Montreal Protocol; member states are now required to phase-down their use of HFCs, with the first cuts planned for 2019. Despite the potential climate implications, atmospheric measurements of HFCs in India, required for quantifying their emissions using top-down inverse methods, have not previously existed. Here we present the first Indian hydrofluorocarbon (HFC) observations, obtained during two months of low altitude (<2000 m) flights. Of the 176 whole air samples collected on board the UK's NERC-FAAM (Facility for Airborne Atmospheric Measurements) research aircraft, the majority were obtained above the Indo-Gangetic Plains of Northern India, where population density is greatest. Using a small subset of samples filled above the Arabian Sea, we derive compound specific baselines, to which the remaining samples are compared. Significant mole fraction enhancements are observed for all major HFCs, indicating the presence of regional emissions sources. Little enhancement is observed in the concentration of various HFC predecessors, including CFCs, suggesting India's success in phasing out the majority of ozone depleting substances. Using these atmospheric observations and the NAME (Numerical Atmospheric dispersion Modelling Environment) atmospheric transport model, we present the first regional HFC flux estimates for India.

  18. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR COLLECTION OF PERSONAL AIR SAMPLES FOR ANALYSIS OF PESTICIDES OR METALS (UA-F-14.0)

    EPA Science Inventory

    The purpose of this SOP is to describe the procedure for sampling personal air for metals and pesticides during a predetermined time period. The SOP includes the set up of the samplers for collection of either a metals sample or a pesticides sample, the calibration and initial c...

  19. Molecular comparison of the sampling efficiency of four types of airborne bacterial samplers.

    PubMed

    Li, Kejun

    2011-11-15

    In the present study, indoor and outdoor air samples were collected using four types of air samplers often used for airborne bacterial sampling. These air samplers included two solid impactors (BioStage and RCS), one liquid impinger (BioSampler), and one filter sampler with two kinds of filters (a gelatin and a cellulose acetate filter). The collected air samples were further processed to analyze the diversity and abundance of culturable bacteria and total bacteria through standard culture techniques, denaturing gradient gel electrophoresis (DGGE) fingerprinting and quantitative polymerase chain reaction (qPCR) analysis. The DGGE analysis indicated that the air samples collected using the BioStage and RCS samplers have higher culturable bacterial diversity, whereas the samples collected using the BioSampler and the cellulose acetate filter sampler have higher total bacterial diversity. To obtain more information on the sampled bacteria, some gel bands were excised and sequenced. In terms of sampling efficiency, results from the qPCR tests indicated that the collected total bacterial concentration was higher in samples collected using the BioSampler and the cellulose acetate filter sampler. In conclusion, the sampling bias and efficiency of four kinds of air sampling systems were compared in the present study and the two solid impactors were concluded to be comparatively efficient for culturable bacterial sampling, whereas the liquid impactor and the cellulose acetate filter sampler were efficient for total bacterial sampling. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Effect of an ozone-generating air-purifying device on reducing concentrations of formaldehyde in air

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Esswein, E.J.; Boeniger, M.F.

    1994-02-01

    Formaldehyde, an air contaminant found in many indoor air investigations, poses distinct occupational exposure hazards in certain job categories (e.g., mortuary science) but is also of concern when found or suspected in office buildings and homes. A variety of air-purifying devices (APDs) are currently available or marketed for application to reduce or remove concentrations of a variety of indoor air pollutants through the use of ozone as a chemical oxidant. An investigation was conducted to determine if concentrations of formaldehyde similar to those found in industrial hygiene evaluations of funeral homes could be reduced with the use of an ozone-generatingmore » APD. An ozone-generating APD was placed in an exposure chamber and formaldehyde-containing embalming solution was allowed to evaporate naturally, creating peak and mean chamber concentrations of 2.5 and 1.3 ppm, respectively. Continuous-reading instruments were used to sample for formaldehyde and ozone. Active sampling methods were also used to sample simultaneously for formaldehyde and a possible reactant product, formic acid. Triplicate measurements were made in each of three evaluations: formaldehyde alone, ozone alone, and formaldehyde and ozone combined. Concentrations of formaldehyde were virtually identical with and without 0.5 ppm ozone. No reduction in formaldehyde concentration was found during a 90-minute evaluation using ozone at this concentration with peak and average concentrations of approximately 2.5 and 1.3 ppm formaldehyde, respectively. The results of this investigation suggest that the use of ozone is ineffective in reducing concentrations of formaldehyde. Because ozone has demonstrated health hazards, and is a regulated air contaminant in both the occupational and ambient environment, the use of ozone as an air purification agent in indoor air does not seem warranted. 25 refs., 5 figs., 4 tabs.« less

  1. Evolution of Fuel-Air and Contaminant Clouds Resulting from a Cruise Missile Explosion Scenario

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grossman, A S; Kul, A L

    2005-06-22

    A low-mach-number hydrodynamics model has been used to simulate the evolution of a fuel-air mixture and contaminant cloud resulting from the detonation of a cruise missile. The detonation has been assumed to be non-nuclear. The cloud evolution has been carried out to a time of 5.5 seconds. At this time the contaminant has completely permeated the initial fuel-air mixture cloud.

  2. BIASES IN CASTNET FILTER PACK RESULTS ASSOCIATED WITH SAMPLING PROTOCOL

    EPA Science Inventory

    In the current study, single filter weekly (w) results are compared with weekly results aggregated from day and night (dn) weekly samples. Comparisons of the two sampling protocols for all major constituents (SO42-, NO3-, NH4+, HNO3, and SO2) show median bias (MB) of < 5 nmol m-3...

  3. Regression sampling: some results for resource managers and researchers

    Treesearch

    William G. O' Regan; Robert W. Boyd

    1974-01-01

    Regression sampling is widely used in natural resources management and research to estimate quantities of resources per unit area. This note brings together results found in the statistical literature in the application of this sampling technique. Conditional and unconditional estimators are listed and for each estimator, exact variances and unbiased estimators for the...

  4. Evaluation of sampling and analytical methods for nicotine and polynuclear aromatic hydrocarbon in indoor air. Final report, 1 February 1987-30 March 1987

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chuang, J.C.; Kuhlman, M.R.; Hannan, S.W.

    1987-11-01

    The objective of this project was to evaluate a potential collection medium, XAD-4 resin, for collecting nicotine and polynuclear aromatic hydrocarbon (PAH) and to determine whether one collection system and one analytical method will allow quantification of both compound classes in air. The extraction efficiency study was to determine the extraction method to quantitatively remove nicotine and PAH from XAD-4 resin. The results showed that a two-step Soxhlet extraction consisting of dichloromethane followed by ethyl acetate resulted in the best recoveries for both nicotine and PAH. In the sampling efficiency study, XAD-2 and XAD-4 resin were compared, in parallel, formore » collection of PAH and nicotine. Quartz fiber filters were placed upstream of both adsorbents to collect particles. Prior to sampling, both XAD-2 and XAD-4 traps were spiked with known amounts (2 microgram) of perdeuterated PAH and D3-nicotine. The experiments were performed with cigarette smoking and nonsmoking conditions. The spiked PAH were retained well in both adsorbents after exposure to more than 300 cu. m. of indoor air. The spiked XAD-4 resin gave higher recoveries for D3-nicotine than did the spiked XAD-2 resin. The collection efficiency for PAH for both adsorbents is very similar but higher levels of nicotine were collected on XAD-4 resin.« less

  5. GICHD mine dog testing project : soil sample results #5.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barnett, James L.; Phelan, James M.; Archuleta, Luisa M.

    2004-01-01

    A mine dog evaluation project initiated by the Geneva International Center for Humanitarian Demining is evaluating the capability and reliability of mine detection dogs. The performance of field-operational mine detection dogs will be measured in test minefields in Afghanistan containing actual, but unfused landmines. Repeated performance testing over two years through various seasonal weather conditions will provide data simulating near real world conditions. Soil samples will be obtained adjacent to the buried targets repeatedly over the course of the test. Chemical analysis results from these soil samples will be used to evaluate correlations between mine dog detection performance and seasonalmore » weather conditions. This report documents the analytical chemical methods and results from the fifth batch of soils received. This batch contained samples from Kharga, Afghanistan collected in June 2003.« less

  6. The role of open-air inhalatoria in the air quality improvement in spa towns.

    PubMed

    Burkowska-But, Aleksandra; Kalwasińska, Agnieszka; Brzezinska, Maria Swiontek

    2014-08-01

    The present study was aimed at evaluating microbiological contamination of air in Ciechocinek and Inowrocław - Polish lowland spa towns. Additionally, the impact of open-air inhalatoria on the quality of air was evaluated. Air samples were collected seasonally in the urban areas, in the recreation areas and in the vicinity of inhalatoria in both towns using impaction. The numbers of mesophilic bacteria, staphylococci, hemolytic bacteria and actinomycetes were determined on media according to the Polish Standard PN-86/Z-04111/02. The number of moulds was determined on media according to the Polish Standard PN-86/Z-04111/03. While the highest numbers of microorganisms were noted at the sites located in the urban areas, the lowest numbers were noted in the vicinity of the open-air inhalatoria. In all the investigated air samples the values of bioaerosol concentrations were below the recommended TLVs (≤ 5000 CFU×m(-3) for both bacteria and fungi in outdoor environments). Location of the sampling site was invariably a decisive factor in determining the number of microorganisms in the air. The aerosol which is formed in the open-air inhalatoria has a positive influence on microbiological air quality. Owing to a unique microclimate and low air contamination, Ciechocinek and Inowrocław comply with all necessary requirements set for health resorts specializing in treating upper respiratory tract infections.

  7. Airborne survey of major air basins in California

    NASA Technical Reports Server (NTRS)

    Gloria, H. R.; Bradburn, G.; Reinisch, R. F.; Pitts, J. N., Jr.; Behar, J. V.; Zafonte, L.

    1974-01-01

    An instrumented aircraft was used to study the chemical and transport properties of air pollution in two major urban centers in California and to survey certain aspects of air pollution within this state. State-of-the-art measurement techniques and sampling procedures are discussed. It is found that meteorological transport mechanisms are better portrayed by vertical pollutant profiles. Airborne measurements define the nature of the mixing layer for atmospheric pollutants. Results show that the pollutants are found to be concentrated in distinct layers up to at least 18,000 feet and the O3 buildup occurring in advected air masses is a result of a continuous photochemical aging of air mass.

  8. [An AIDS-related cognitive map in a sample of drug abusers in Buenos Aires City].

    PubMed

    Kornblit, A L; Bilyk, A

    1990-01-01

    This paper is an approach to AIDS as a topic among a drug abusers sample of the city of Buenos Aires. Research was carried out on the basis of a qualitative methodology. In an attempt at surveying opinions and attitudes of such a sample as regards AIDS (i.e. subjects' cognitive map), 21 drug abusers from three different rehabilitation programs operating in the B.A. area were interviewed. On the basis of the research performed, the authors elaborate communication strategies among drug abusers that would be helpful for authorities engaged in AIDS prevention to adopt. To boost a strategy likely to break up the AIDS-drug association existing in the mind of many an abuser would be highly advisable so that a separation be settled between both representations, thus giving drug abusers a higher motivation for self-care practice.

  9. Saturation sampling for spatial variation in multiple air pollutants across an inversion-prone metropolitan area of complex terrain

    PubMed Central

    2014-01-01

    Background Characterizing intra-urban variation in air quality is important for epidemiological investigation of health outcomes and disparities. To date, however, few studies have been designed to capture spatial variation during select hours of the day, or to examine the roles of meteorology and complex terrain in shaping intra-urban exposure gradients. Methods We designed a spatial saturation monitoring study to target local air pollution sources, and to understand the role of topography and temperature inversions on fine-scale pollution variation by systematically allocating sampling locations across gradients in key local emissions sources (vehicle traffic, industrial facilities) and topography (elevation) in the Pittsburgh area. Street-level integrated samples of fine particulate matter (PM2.5), black carbon (BC), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) were collected during morning rush and probable inversion hours (6-11 AM), during summer and winter. We hypothesized that pollution concentrations would be: 1) higher under inversion conditions, 2) exacerbated in lower-elevation areas, and 3) vary by season. Results During July - August 2011 and January - March 2012, we observed wide spatial and seasonal variability in pollution concentrations, exceeding the range measured at regulatory monitors. We identified elevated concentrations of multiple pollutants at lower-elevation sites, and a positive association between inversion frequency and NO2 concentration. We examined temporal adjustment methods for deriving seasonal concentration estimates, and found that the appropriate reference temporal trend differs between pollutants. Conclusions Our time-stratified spatial saturation approach found some evidence for modification of inversion-concentration relationships by topography, and provided useful insights for refining and interpreting GIS-based pollution source indicators for Land Use Regression modeling. PMID:24735818

  10. Chemical trends in background air quality and the ionic composition of precipitation for the period 1980-2004 from samples collected at Valentia Observatory, Co. Kerry, Ireland.

    PubMed

    Bashir, Wasim; McGovern, Frank; O'Brien, Phillip; Ryan, Margaret; Burke, Liam; Paull, Brett

    2008-06-01

    A major Irish study, based upon more than 8000 samples collected over the measurement period of 22 years, for sulfur dioxide (SO2-S), sulfate (SO4-S) and nitrogen dioxide (NO2-N) concentrations (microg m(-3)) within air, and the ionic composition of precipitation samples based on sodium (Na+), potassium (K+), magnesium (Mg2+), calcium (Ca2+), chloride (Cl-), sulfate (SO4-S), non-sea salt sulfate (nssSO4-S), ammonium (NH4-N), and nitrate (NO3-N) weighted mean concentrations (mg l(-1)), has been completed. For the air samples, the sulfur dioxide and sulfate concentrations decreased over the sampling period (1980-2004) by 75% and 45%, respectively, whereas no significant trend was observed for nitrogen dioxide. The highest concentrations for sulfur dioxide, sulfate and nitrogen dioxide were associated with wind originating from the easterly and northeasterly directions i.e. those influenced by Irish and European sources. The lowest concentrations were associated with the westerly directions i.e. for air masses originating in the North Atlantic region. This was further verified with the use of backward (back) trajectory analysis, which allowed tracing the movement of air parcels using the European Centre for Medium range Weather Forecasting (ECMWF) ERA-40 re-analysis data. High non-sea salt sulfate levels were being associated with air masses originating from Europe (easterlies) with lower levels from the Atlantic (westerlies). With the precipitation data, analysis of the non-sea salt sulfate concentrations showed a decrease by 47% since the measurements commenced.

  11. Characterization of the bacterial and fungal microbiome in indoor dust and outdoor air samples: a pilot study†

    PubMed Central

    Hanson, Blake; Zhou, Yanjiao; Bautista, Eddy J.; Urch, Bruce; Speck, Mary; Silverman, Frances; Muilenberg, Michael; Phipatanakul, Wanda; Weinstock, George; Sodergren, Erica; Gold, Diane R.; Sordillo, Joanne E.

    2016-01-01

    Environmental microbes have been associated with both protective and adverse health effects in children and adults. Epidemiological studies often rely on broad biomarkers of microbial exposure (i.e. endotoxin, 1→3, Beta-D glucan), but fail to identify the taxonomic composition of the microbial community. Our aim was to characterize the bacterial and fungal microbiome in different types of environmental samples collected in studies of human health effects. We determined the composition of microbial communities present in home, school and outdoor air samples by amplifying and sequencing regions of rRNA genes from bacteria (16S) and fungi (18S and ITS). Samples for this pilot study included indoor settled dust (from both a Boston area birth cohort study on Home Allergens and Asthma (HAA)(n=12) and a study of school exposures and asthma symptoms (SICAS) (n=1)), as well as fine and coarse concentrated outdoor ambient particulate (CAP) samples (n=9). Sequencing of amplified 16S, 18S, and ITS regions was performed on the Roche-454 Life Sciences Titanium pyrosequencing platform. Indoor dust samples were dominated by gram-positive bacteria (Firmicutes and Actinobacteria); the most abundant bacterial genera were those related to human flora (Streptococcus, Staphylococcus, Corynebacterium and Lactobacillus). Outdoor CAPs were dominated by gram-negative Proteobacteria from water and soil sources, in particular the genera Acidovorax, and Brevundimonas (which were present at very low levels or entirely absent in indoor dust). Phylum-level fungal distributions identified by 18S or ITS regions showed very similar findings: a predominance of Ascomycota in indoor dust and Basidiomycota in outdoor CAPs. ITS sequencing of fungal genera in indoor dust showed significant proportions of Aureobasidium and Leptosphaerulina along with some contribution from Cryptococcus, Epicoccum, Aspergillus and the human commensal Malassezia. ITS sequencing detected an additional 70 fungal genera in

  12. Indoor air quality in Latino homes in Boulder, Colorado

    NASA Astrophysics Data System (ADS)

    Escobedo, Luis E.; Champion, Wyatt M.; Li, Ning; Montoya, Lupita D.

    2014-08-01

    Indoor concentrations of airborne pollutants can be several times higher than those found outdoors, often due to poor ventilation, overcrowding, and the contribution of indoor sources within a home. Americans spend most of their time indoors where exposure to poor indoor air quality (IAQ) can result in diminished respiratory and cardiovascular health. This study measured the indoor air quality in 30 homes of a low-income Latino community in Boulder, Colorado during the summer of 2012. Participants were administered a survey, which included questions on their health conditions and indoor air pollution sources like cigarette smoke, heating fuel, and building materials. Twenty-four hour samples of fine particulate matter (PM2.5) from the indoor air were collected in each home; ambient PM2.5 samples were collected each day as well. Concurrent air samples were collected onto 47 mm Teflo and Tissuquartz filter at each location. Teflo filters were analyzed gravimetrically to measure PM2.5 and their extracts were used to determine levels of proteins and endotoxins in the fine fraction. The Tissuquartz filters were analyzed for elemental and organic carbon content (EC/OC). Results indicated that the indoor air contained higher concentrations of PM2.5 than the ambient air, and that the levels of OC were much higher than EC in both indoor and outdoor samples. This community showed no smoking in their homes and kept furry pets indoors at very low rates; therefore, cooking is likely the primary source of indoor PM. For responders with significant exposure to PM, it appeared to be primarily from occupational environments or childhood exposure abroad. Our findings indicate that for immigrant communities such as this, it is important to consider not only their housing conditions but also the relevant prior exposures when conducting health assessments.

  13. It's Alive!: Students Observe Air-Water Interface Samples Rich with Organisms

    ERIC Educational Resources Information Center

    Avant, Thomas

    2002-01-01

    This article describes an experiment, designed by Cindy Henk, manager of the Socolofsky Microscopy Center at Louisiana State University (LSU), that involved collecting and viewing microorganisms in the air-water interface. The experiment was participated by Leesville High School microbiology students. The students found that the air-water…

  14. The molecular characteristics of avian influenza viruses (H9N2) derived from air samples in live poultry markets.

    PubMed

    Wu, Yanheng; Lin, Jinsi; Yang, Shuhuan; Xie, Ying; Wang, Man; Chen, Xueqin; Zhu, Yayang; Luo, Le; Shi, Wuyang

    2018-06-01

    To study the molecular characteristics of H9N2-subtype avian influenza viruses (AIVs) isolated from air samples collected in live poultry markets (LPMs) and explore their sequence identities with AIVs that caused human infection. Weekly surveillance of H9N2-subtype AIVs in the air of LPMs was conducted from 2015 to 2016. H9-positive samples were isolated from chicken embryos. Whole genome sequences of the isolated AIVs were obtained through high-throughput sequencing. Phylogenetic analysis and key loci variations of the sequences were further analyzed. A total of 327 aerosol samples were collected from LPMs. Nine samples were positive for H9-subtype AIVs based on quantitative real-time reverse transcription polymerase chain reaction (qRRT-PCR). According to the whole genome sequence analysis and phylogenetic analysis, except for the A/Environment/Zhongshan/ZS201505/2015 (ZS201505) strain, 8 gene segments of 8 aerosol H9N2 isolates and 2 H9N2 human isolates in 2015 were located in the same clade. Among key loci variations, except for the ZS201505 strain, H9N2-subtype AIVs had no mutations in eight receptor binding sites of hemagglutinin (HA), and stalks of neuraminidase (NA) proteins exhibited a deletion site of three bases. The PA gene of ZS201503 and ZS201602 exhibited an L336M mutation. The N30D and T215A mutations in the M1 gene and amino acid residues L89V in PB2, P42S in NS1 and S31N in M2 were retained in these 9 strains of H9N2 isolates, which could enhance the virus's virulence. Live H9N2 AIVs survived in the aerosol of LPMs in Zhongshan City. The aerosol viruses had a close evolutionary relationship with human epidemic strains, indicating that there might be a risk of AIV transmission from polluted aerosols in LPMs to humans. Mutations in H9N2-subtype AIVs isolated from air samples collected from LPMs suggested their pathogenicity was enhanced to infect humans. Copyright © 2018. Published by Elsevier B.V.

  15. Determination of formaldehyde by HPLC as the DNPH derivative following high-volume air sampling onto bisulfite-coated cellulose filters

    NASA Astrophysics Data System (ADS)

    de Andrade, Jailson B.; Tanner, Roger L.

    A method is described for the specific collection of formaldehyde as hydroxymethanesulfonate on bisulfate-coated cellulose filters. Following extraction in aqueous acid and removal on unreacted bisulfite, the hydroxymethanesulfonate is decomposed by base, and HCHO is determined by DNPH (2,4-dinitrophenylhydrazine) derivatization and HPLC. Since the collection efficiency for formaldehyde is moderately high even when sampling ambient air at high-volume flow rates, a limit of detection of 0.2 ppbv is achieved with 30 min sampling times. Interference from acetaldehyde co-collected as 1-hydroxyethanesulfonate is <5% using this procedure. The technique shows promise for both short-term airborne sampling, and as a means of collecting mg-sized samples of HCHO on an inorganic matrix for carbon isotopic analyses.

  16. Comparison of air-coupled GPR data analysis results determined by multiple analysts

    NASA Astrophysics Data System (ADS)

    Martino, Nicole; Maser, Ken

    2016-04-01

    Current bridge deck condition assessments using ground penetrating radar (GPR) requires a trained analyst to manually interpret substructure layering information from B-scan images in order to proceed with an intended analysis (pavement thickness, concrete cover, effects of rebar corrosion, etc.) For example, a recently developed method to rapidly and accurately analyze air-coupled GPR data based on the effects of rebar corrosion, requires that a user "picks" a layer of rebar reflections in each B-scan image collected along the length of the deck. These "picks" have information like signal amplitude and two way travel time. When a deck is new, or has little rebar corrosion, the resulting layer of rebar reflections is readily evident and there is little room for subjectivity. However, when a deck is severely deteriorated, the rebar layer may be difficult to identify, and different analysts may make different interpretations of the appropriate layer to analyze. One highly corroded bridge deck, was assessed with a number of nondestructive evaluation techniques including 2GHz air-coupled GPR. Two trained analysts separately selected the rebar layer in each B-scan image, choosing as much information as possible, even in areas of significant deterioration. The post processing of the selected data points was then completed and the results from each analyst were contour plotted to observe any discrepancies. The paper describes the differences between ground coupled and air-coupled GPR systems, the data collection and analysis methods used by two different analysts for one case study, and the results of the two different analyses.

  17. Monitoring Air Quality with Leaf Yeasts.

    ERIC Educational Resources Information Center

    Richardson, D. H. S.; And Others

    1985-01-01

    Proposes that leaf yeast serve as quick, inexpensive, and effective techniques for monitoring air quality. Outlines procedures and provides suggestions for data analysis. Includes results from sample school groups who employed this technique. (ML)

  18. Quantification of fluorine traces in solid samples using CaF molecular emission bands in atmospheric air Laser-Induced Breakdown Spectroscopy

    NASA Astrophysics Data System (ADS)

    Alvarez-Llamas, C.; Pisonero, J.; Bordel, N.

    2016-09-01

    Direct solid determination of trace amounts of fluorine using Laser-Induced Breakdown Spectroscopy (LIBS) is a challenging task due to the low excitation efficiency of this element. Several strategies have been developed to improve the detection capabilities, including the use of LIBS in a He atmosphere to enhance the signal to background ratios of F atomic emission lines. An alternative method is based on the detection of the molecular compounds that are formed with fluorine in the LIBS plasma. In this work, the detection of CaF molecular emission bands is investigated to improve the analytical capabilities of atmospheric air LIBS for the determination of fluorine traces in solid samples. In particular, Cu matrix samples containing different fluorine concentration (between 50 and 600 μg/g), and variable amounts of Ca, are used to demonstrate the linear relationships between CaF emission signal and F concentration. Limits of detection for fluorine are improved by more than 1 order of magnitude using CaF emission bands versus F atomic lines, in atmospheric-air LIBS. Furthermore, a toothpaste powder sample is used to validate this analytical method. Good agreement is observed between the nominal and the predicted fluorine mass-content.

  19. GICHD mine dog testing project - soil sample results #4.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barnett, James L.; Phelan, James M.; Archuleta, Luisa M.

    2003-08-01

    A mine dog evaluation project initiated by the Geneva International Center for Humanitarian Demining is evaluating the capability and reliability of mine detection dogs. The performance of field-operational mine detection dogs will be measured in test minefields in Afghanistan and Bosnia containing actual, but unfused landmines. Repeated performance testing over two years through various seasonal weather conditions will provide data simulating near real world conditions. Soil samples will be obtained adjacent to the buried targets repeatedly over the course of the test. Chemical analysis results from these soil samples will be used to evaluate correlations between mine dog detection performancemore » and seasonal weather conditions. This report documents the analytical chemical methods and results from the fourth batch of soils received. This batch contained samples from Kharga, Afghanistan collected in April 2003 and Sarajevo, Bosnia collected in May 2003.« less

  20. 30 CFR 71.701 - Sampling; general requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Sampling; general requirements. 71.701 Section... MINES Airborne Contaminants § 71.701 Sampling; general requirements. (a) Air samples will be taken by... operator shall conduct any additional air sampling tests and analyses as the Secretary may from time to...

  1. 30 CFR 71.701 - Sampling; general requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Sampling; general requirements. 71.701 Section... MINES Airborne Contaminants § 71.701 Sampling; general requirements. (a) Air samples will be taken by... operator shall conduct any additional air sampling tests and analyses as the Secretary may from time to...

  2. Urinary Biomarker, Dermal, and Air Measurement Results for 2,4-D and Chlorpyrifos Farm Applicators in the Agricultural Health Study

    PubMed Central

    Thomas, Kent; Dosemeci, Mustafa; Hoppin, Jane A.; Sheldon, Linda; Croghan, Carry; Gordon, Sydney; Jones, Martin; Reynolds, Stephen; Raymer, James; Akland, Gerald; Lynch, Charles F.; Knott, Charles; Sandler, Dale P.; Blair, Aaron; Alavanja, Michael

    2010-01-01

    Epidemiologic studies increasingly rely on improved exposure assessments to characterize pesticide exposures in agricultural populations. A subset of private pesticide applicators in the AHS epidemiological cohort was monitored around the time of their agricultural use of 2,4-D and chlorpyrifos to assess exposure levels and potential exposure factors. Measurements included pre- and post-application urine samples, and patch, hand wipe, and personal air samples. Broadcast or hand spray application methods were used by applicators for 2,4-D products. Chlorpyrifos products were applied using spray applications and in-furrow application of granular products. Geometric mean (GM) values for 69 2,4-D applicators were 7.8 and 25 µg/L in pre- and post-application urine, respectively (p < 0.05 for difference); 0.39 mg for estimated hand loading; 2.9 mg for estimated body loading; and 0.37 µg/m3 for concentration in personal air. Significant correlations were found between all media for 2,4-D. GM values for 17 chlorpyrifos applicators were 11 µg/L in both pre- and post-application urine for the 3,5,6-trichloro-2-pyridinol metabolite, 0.28 mg for body loading, and 0.49 µg/m3 for air concentration. Only 53% of the chlorpyrifos applicators had measureable hand loading results; their median hand loading was 0.02 mg. Factors associated with differences in 2,4-D measurements included application method and glove use; and, for hand spray applicators, use of adjuvants, equipment repair, duration of use, and contact with treated vegetation. Spray applications of liquid chlorpyrifos products were associated with higher measurements than in-furrow granular product applications. This study provides information on exposures and possible exposure determinants for several application methods commonly used by farmers in the cohort and will provide information to assess and refine exposure classification in the Agricultural Health Study. Results may also be of use in pesticide safety

  3. Microbiological contamination of compressed air used in dentistry: an investigation.

    PubMed

    Conte, M; Lynch, R M; Robson, M G

    2001-11-01

    The purpose of this preliminary investigation was twofold: 1) to examine the possibility of cross-contamination between a dental-evacuation system and the compressed air used in dental operatories and 2) to capture and identify the most common microflora in the compressed-air supply. The investigation used swab, water, and air sampling that was designed to track microorganisms from the evacuation system, through the air of the mechanical room, into the compressed-air system, and back to the patient. Samples taken in the vacuum system, the air space in the mechanical room, and the compressed-air storage tank had significantly higher total concentrations of bacteria than the outside air sampled. Samples of the compressed air returning to the operatory were found to match the outside air sample in total bacteria. It was concluded that the air dryer may have played a significant role in the elimination of microorganisms from the dental compressed-air supply.

  4. Target location after deep cerebral biopsies using low-volume air injection in 75 patients. Results and technical note.

    PubMed

    Poca, Maria A; Martínez-Ricarte, Francisco-Ramon; Gándara, Dario F; Coscojuela, Pilar; Martínez-Sáez, Elena; Sahuquillo, Juan

    2017-10-01

    Stereotactic biopsy is a minimally invasive technique that allows brain tissue samples to be obtained with low risk. Classically, different techniques have been used to identify the biopsy site after surgery. To describe a technique to identify the precise location of the target in the postoperative CT scan using the injection of a low volume of air into the biopsy cannula. Seventy-five biopsies were performed in 65 adults and 10 children (40 males and 35 females, median age 51 years). Frame-based biopsy was performed in 46 patients, while frameless biopsy was performed in the remaining 29 patients. In both systems, after brain specimens had been collected and with the biopsy needle tip in the center of the target, a small volume of air (median 0.7 cm 3 ) was injected into the site. A follow-up CT scan was performed in all patients. Intracranial air in the selected target was present in 69 patients (92%). No air was observed in two patients (air volume administered in these 2 cases was below 0.7 cm 3 ), while in the remaining four patients blood content was observed in the target. The diagnostic yield in this series was 97.3%. No complications were found to be associated with intracranial air injection in any of the 75 patients who underwent this procedure. The air-injection maneuver proposed for use in stereotactic biopsies of intracranial mass lesions is a safe and reliable technique that allows the exact biopsy site to be located without any related complications.

  5. Review of Various Air Sampling Methods for Solvent Vapors.

    ERIC Educational Resources Information Center

    Maykoski, R. T.

    Vapors of trichloroethylene, toluene, methyl ethyl ketone, and butyl cellosolve in air were collected using Scotchpac and Tedlar bags, glass prescription bottles, and charcoal adsorption tubes. Efficiencies of collection are reported. (Author/RH)

  6. Remote possibly hazardous content container sampling device

    DOEpatents

    Volz, David L.

    1998-01-01

    The present invention relates to an apparatus capable of sampling enclosed containers, where the contents of the container is unknown. The invention includes a compressed air device capable of supplying air pressure, device for controlling the amount of air pressure applied, a pneumatic valve, a sampling device having a hollow, sampling insertion needle suspended therein and device to communicate fluid flow between the container and a containment vessel, pump or direct reading instrument.

  7. Field Evaluation of a Passive Sampling Device for Hydrazines in Ambient Air

    DTIC Science & Technology

    1990-04-06

    MANIDIFUIOFOBELFO Figure 2. Test gas generator schematic. Conditioned house- compressed air is used as the diluent. The conditioning procedure consists...of passing the house air through a series of demisters, a hot Hopcalite catalyst bed, a reciprocating dual-tower molecular sieve scrubber, and finally... Air P. A. TAFFE,* S. W. BROWN,** A. R. THUROW,*** J. C. TRAvIs**** *GEO-Centers Inc., **EG&G, BOC-022, KSC, FL . . F. ***Wiltech Corp., KSC, FL MAY 0

  8. Influence of air quality on the results of in vitro fertilization attempts: A retrospective study.

    PubMed

    Carré, Julie; Gatimel, Nicolas; Moreau, Jessika; Parinaud, Jean; Leandri, Roger

    2017-03-01

    To assess the influence of air quality on the results of IVF. We performed a retrospective study on 292 patients who have undergone an IVF attempt from April 2012 to December 2015 in our French university hospital. Patients were included in the study if data on the air quality at home and at work were available and if they haven't been gone for more than 4days in a month. Data were recorded during the 3 months before oocyte collection and 1 month after embryo transfer. Air quality measurements were obtained from the Observatoire Régional de l'Air en Midi-Pyrénées (ORAMIP) and concerned the levels of nitrogen dioxide (NO 2 ), ozone (O 3 ), particulate matter PM10 and SO 2 measured every day. Acute exposures to high levels NO 2 or PM10 were associated with lower results of IVF (ovarian response to stimulation, number of top embryos) while these parameters were enhanced when patients were exposed to high levels of O 3 during the first 2 months of folliculogenesis. These effects were found even for a short exposure (1day). Air quality has an impact on global health and also on the reproductive function and public and authorities must be aware of environmental protection. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Demonstration/Validation of the Snap Sampler Passive Groundwater Sampling Device at the Former McClellan Air Force Base

    DTIC Science & Technology

    2011-02-01

    and Development Center Fe Iron gpd Gallons per Day HDPE High Density Polyethylene Hg Mercury ICP Inductively Coupled Plasma ICP/MS...Inductively Coupled Plasma Mass Spectrometry IROD Interim Record of Decision ITRC Interstate Technology and Regulatory Council K Potassium Kow...alkaline earth metals, alkali metals, and a metalloid, were sampled. This particular demonstration took place at the McClellan Air Force Base (AFB) in

  10. Assessing polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in air across Latin American countries using polyurethane foam disk passive air samplers.

    PubMed

    Schuster, Jasmin K; Harner, Tom; Fillmann, Gilberto; Ahrens, Lutz; Altamirano, Jorgelina C; Aristizábal, Beatriz; Bastos, Wanderley; Castillo, Luisa Eugenia; Cortés, Johana; Fentanes, Oscar; Gusev, Alexey; Hernandez, Maricruz; Ibarra, Martín Villa; Lana, Nerina B; Lee, Sum Chi; Martínez, Ana Patricia; Miglioranza, Karina S B; Puerta, Andrea Padilla; Segovia, Federico; Siu, May; Tominaga, Maria Yumiko

    2015-03-17

    A passive air sampling network has been established to investigate polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) at Global Atmospheric Passive Sampling (GAPS) sites and six additional sites in the Group of Latin American and Caribbean Countries (GRULAC) region. The air sampling network covers background, agricultural, rural, and urban sites. Samples have been collected over four consecutive periods of 6 months, which started in January 2011 [period 1 (January to June 2011), period 2 (July to December 2011), period 3 (January to June 2012), and period 4 (July 2012 to January 2013)]. Results show that (i) the GAPS passive samplers (PUF disk type) and analytical methodology are adequate for measuring PCDD/F burdens in air and (ii) PCDD/F concentrations in air across the GRULAC region are widely variable by almost 2 orders of magnitude. The highest concentrations in air of Σ4-8PCDD/Fs were found at the urban site São Luis (Brazil, UR) (i.e., 2560 fg/m3) followed by the sites in São Paulo (Brazil, UR), Mendoza (Argentina, RU), and Sonora (Mexico, AG) with values of 1690, 1660, and 1610 fg/m3, respectively. Very low concentrations of PCDD/Fs in air were observed at the background site Tapanti (Costa Rica, BA), 10.8 fg/m3. This variability is attributed to differences in site characteristics and potential local/regional sources as well as meteorological influences. The measurements of PCDD/Fs in air agree well with model-predicted concentrations performed using the Global EMEP Multimedia Modeling System (GLEMOS) and emission scenario constructed on the basis of the UNEP Stockholm Convention inventory of dioxin and furan emissions.

  11. Nitrogen and triple oxygen isotopes in near-road air samples using chemical conversion and thermal decomposition.

    PubMed

    Smirnoff, Anna; Savard, Martine M; Vet, Robert; Simard, Marie-Christine

    2012-12-15

    The determination of triple oxygen (δ(18)O and δ(17)O) and nitrogen isotopes (δ(15)N) is important when investigating the sources and atmospheric paths of nitrate and nitrite. To fully understand the atmospheric contribution into the terrestrial nitrogen cycle, it is crucial to determine the δ(15)N values of oxidised and reduced nitrogen species in precipitation and dry deposition. In an attempt to further develop non-biotic methods and avoid expensive modifications of the gas-equilibration system, we have combined and modified sample preparation procedures and analytical setups used by other researchers. We first chemically converted NO(3)(-) and NH(4)(+) into NO(2)(-) and then into N(2)O. Subsequently, the resulting gas was decomposed into N(2) and O(2) and analyzed by isotope ratio mass spectrometry (IRMS) using a pre-concentration system equipped with a gold reduction furnace. The δ(17)O, δ(18)O and δ(15)N values of nitrate and nitrite samples were acquired simultaneously in one run using a single analytical system. Most importantly, the entire spectrum of δ(17)O, δ(18)O and/or δ(15)N values was determined from atmospheric nitrate, nitric oxide, ammonia and ammonium. The obtained isotopic values for air and precipitation samples were in good agreement with those from previous studies. We have further advanced chemical approaches to sample preparation and isotope analyses of nitrogen-bearing compounds. The proposed methods are inexpensive and easily adaptable to a wide range of laboratory conditions. This will substantially contribute to further studies on sources and pathways of nitrate, nitrite and ammonium in terrestrial nitrogen cycling. Copyright © 2012 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.

  12. ISS Potable Water Sampling and Chemical Analysis Results for 2016

    NASA Technical Reports Server (NTRS)

    Straub, John E., II; Plumlee, Debrah K.; Wallace William T.; Alverson, James T.; Benoit, Mickie J.; Gillispie, Robert L.; Hunter, David; Kuo, Mike; Rutz, Jeffrey A.; Hudson, Edgar K.; hide

    2017-01-01

    This paper continues the annual tradition of summarizing at this conference the results of chemical analyses performed on archival potable water samples returned from the International Space Station (ISS). 2016 represented a banner year for life on board the ISS, including the successful conclusion for two crew members of a record one-year mission. Water reclaimed from urine and/or humidity condensate remained the primary source of potable water for the crew members of ISS Expeditions 46-50. The year 2016 was also marked by the end of a long-standing tradition of U.S. sampling and monitoring of Russian Segment potable water sources. Two water samples taken during Expedition 46 in February 2016 and returned on Soyuz 44, represented the final Russian Segment samples to be collected and analyzed by the U.S. side. Although anticipated for 2016, a rise in the total organic carbon (TOC) concentration of the product water from the U.S. water processor assembly due to breakthrough of organic contaminants from the system did not materialize, as evidenced by the onboard TOC analyzer and archive sample results.

  13. ISS Potable Water Sampling and Chemical Analysis Results for 2016

    NASA Technical Reports Server (NTRS)

    Straub, John E., II; Plumlee, Debrah K.; Wallace, William T.; Alverson, James T.; Benoit, Mickie J.; Gillispie, Robert L.; Hunter, David; Kuo, Mike; Rutz, Jeffrey A.; Hudson, Edgar K.; hide

    2017-01-01

    This paper continues the annual tradition, at this conference, of summarizing the results of chemical analyses performed on archival potable water samples returned from the International Space Station (ISS). 2016 represented a banner year for life aboard the ISS, including the successful conclusion for 2 crewmembers of a record 1-year mission. Water reclaimed from urine and/or humidity condensate remained the primary source of potable water for the crewmembers of ISS Expeditions 46-50. The year was also marked by the end of a long-standing tradition of U.S. sampling and monitoring of Russian Segment potable water sources. Two water samples, taken during Expedition 46 and returned on Soyuz 44 in March 2016, represented the final Russian Segment samples to be collected and analyzed by the U.S. side. Although anticipated for 2016, a rise in the total organic carbon (TOC) concentration of the product water from the U.S. water processor assembly due to breakthrough of organic contaminants from the system did not materialize, as evidenced by the onboard TOC analyzer and archival sample results.

  14. PCDD/PCDF and dl-PCB in the ambient air of a tropical Andean city: passive and active sampling measurements near industrial and vehicular pollution sources.

    PubMed

    Cortés, J; González, C M; Morales, L; Abalos, M; Abad, E; Aristizábal, B H

    2014-09-01

    Concentration gradients were observed in gas and particulate phases of PCDD/F originating from industrial and vehicular sources in the densely populated tropical Andean city of Manizales, using passive and active air samplers. Preliminary results suggest greater concentrations of dl-PCB in the mostly gaseous fraction (using quarterly passive samplers) and greater concentrations of PCDD/F in the mostly particle fraction (using daily active samplers). Dioxin-like PCB predominance was associated with the semi-volatility property, which depends on ambient temperature. Slight variations of ambient temperature in Manizales during the sampling period (15°C-27°C) may have triggered higher concentrations in all passive samples. This was the first passive air sampling monitoring of PCDD/F conducted in an urban area of Colombia. Passive sampling revealed that PCDD/F in combination with dioxin-like PCB ranged from 16 WHO-TEQ2005/m(3) near industrial sources to 7 WHO-TEQ2005/m(3) in an intermediate zone-a reduction of 56% over 2.8 km. Active sampling of particulate phase PCDD/F and dl-PCB were analyzed in PM10 samples. PCDD/F combined with dl-PCB ranged from 46 WHO-TEQ2005/m(3) near vehicular sources to 8 WHO-TEQ2005/m(3) in the same intermediate zone, a reduction of 83% over 2.6 km. Toxic equivalent quantities in both PCDD/F and dl-PCB decreased toward an intermediate zone of the city. Variations in congener profiles were consistent with variations expected from nearby sources, such as a secondary metallurgy plant, areas of concentrated vehicular emissions and a municipal solid waste incinerator (MSWI). These variations in congener profile measurements of dioxins and dl-PCBs in passive and active samples can be partly explained by congener variations expected from the various sources. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. 40 CFR 1065.805 - Sampling system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Sampling system. 1065.805 Section 1065.805 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... background samples for correcting dilution air for background concentrations of alcohols and carbonyls. (c...

  16. 40 CFR 1065.805 - Sampling system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Sampling system. 1065.805 Section 1065.805 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... background samples for correcting dilution air for background concentrations of alcohols and carbonyls. (c...

  17. 40 CFR 1065.805 - Sampling system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Sampling system. 1065.805 Section 1065.805 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... background samples for correcting dilution air for background concentrations of alcohols and carbonyls. (c...

  18. Time Trends of Polycyclic Aromatic Hydrocarbon Exposure in New York City from 2001 to 2012: Assessed by Repeat Air and Urine Samples

    PubMed Central

    Jung, Kyung Hwa; Liu, Bian; Lovinsky-Desir, Stephanie; Yan, Beizhan; Camann, David; Sjodin, Andreas; Li, Zheng; Perera, Frederica; Kinney, Patrick; Chillrud, Steven; Miller, Rachel L.

    2014-01-01

    Background Exposure to air pollutants including polycyclic aromatic hydrocarbons (PAH), and specifically pyrene from combustion of fuel oil, coal, traffic and indoor sources, has been associated with adverse respiratory health outcomes. However, time trends of airborne PAH and metabolite levels detected via repeat measures over time have not yet been characterized. We hypothesized that PAH levels, measured repeatedly from residential indoor and outdoor monitors, and children’s urinary concentrations of PAH metabolites, would decrease following policy interventions to reduce traffic-related air pollution. Methods Indoor PAH (particle- and gas-phase) were collected for two weeks prenatally (n=98), at age 5/6 years (n=397) and age 9/10 years (n=198) since 2001 and at all three age-points (n=27). Other traffic-related air pollutants (black carbon and PM2.5) were monitored indoors simultaneous with PAH monitoring at ages 5/6 (n=403) and 9/10 (n=257) between 2005 and 2012. One third of the homes were selected across seasons for outdoor PAH, BC and PM2.5 sampling. Using the same sampling method, ambient PAH, BC and PM2.5 also were monitored every two weeks at a central site between 2007 and 2012. PAH were analyzed as semivolatile PAH (e.g., pyrene; MW 178–206) and the sum of eight nonvolatile PAH (Σ8PAHnonvolatile; MW 228–278). A spot urine sample was collected from children at child ages 3, 5, 7 and 9 between 2001 and 2012 and analyzed for 10 PAH metabolites. Results Modest declines were detected in indoor BC and PM2.5 levels between 2005 and 2012 (Annual percent change [APC]=−2.08% [p=0.010] and −2.18% [p=0.059] for BC and PM2.5, respectively), while a trend of increasing pyrene levels was observed in indoor and outdoor samples, and at the central site during the comparable time periods (APC=4.81%, 3.77% and 7.90%, respectively; p<0.05 for all). No significant time trend was observed in indoor Σ8PAHnonvolatile levels between 2005 and 2012; however

  19. An automated atmospheric sampling system operating on 747 airliners

    NASA Technical Reports Server (NTRS)

    Perkins, P.; Gustafsson, U. R. C.

    1975-01-01

    An air sampling system that automatically measures the temporal and spatial distribution of selected particulate and gaseous constituents of the atmosphere has been installed on a number of commercial airliners and is collecting data on commercial air routes covering the world. Measurements of constituents related to aircraft engine emissions and other pollutants are made in the upper troposphere and lower stratosphere (6 to 12 km) in support of the Global Air Sampling Program (GASP). Aircraft operated by different airlines sample air at latitudes from the Arctic to Australia. This system includes specialized instrumentation for measuring carbon monoxide, ozone, water vapor, and particulates, a special air inlet probe for sampling outside air, a computerized automatic control, and a data acquisition system. Air constituents and related flight data are tape recorded in flight for later computer processing on the ground.

  20. Eight Year Climatologies from Observational (AIRS) and Model (MERRA) Data

    NASA Technical Reports Server (NTRS)

    Hearty, Thomas; Savtchenko, Andrey; Won, Young-In; Theobalk, Mike; Vollmer, Bruce; Manning, Evan; Smith, Peter; Ostrenga, Dana; Leptoukh, Greg

    2010-01-01

    We examine climatologies derived from eight years of temperature, water vapor, cloud, and trace gas observations made by the Atmospheric Infrared Sounder (AIRS) instrument flying on the Aqua satellite and compare them to similar climatologies constructed with data from a global assimilation model, the Modern Era Retrospective-Analysis for Research and Applications (MERRA). We use the AIRS climatologies to examine anomalies and trends in the AIRS data record. Since sampling can be an issue for infrared satellites in low earth orbit, we also use the MERRA data to examine the AIRS sampling biases. By sampling the MERRA data at the AIRS space-time locations both with and without the AIRS quality control we estimate the sampling bias of the AIRS climatology and the atmospheric conditions where AIRS has a lower sampling rate. While the AIRS temperature and water vapor sampling biases are small at low latitudes, they can be more than a few degrees in temperature or 10 percent in water vapor at higher latitudes. The largest sampling biases are over desert. The AIRS and MERRA data are available from the Goddard Earth Sciences Data and Information Services Center (GES DISC). The AIRS climatologies we used are available for analysis with the GIOVANNI data exploration tool. (see, http://disc.gsfc.nasa.gov).

  1. Analytical Results from Routine DSSHT and SEHT Monthly Samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peters, T. B.

    2016-08-17

    Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the “microbatches” of Integrated Salt Disposition Project (ISDP) Salt Batch (“Macrobatch”) 8B have been analyzed for 238Pu, 90Sr, 137Cs, cations (Inductively Coupled Plasma Emission Spectroscopy - ICPES), and anions (Ion Chromatography Anions - IC-A). The analytical results from the current microbatch samples are similar to those from previous macrobatch samples. The Actinide Removal Process (ARP) and the Modular Caustic-Side Solvent Extraction Unit (MCU) continue to show more than adequate Pu and Sr removal for times when monosodium titanate (MST) is used. Even with nomore » MST strike being performed there exists some small Pu and Sr removal, likely from filtration of fines containing these elements. The Cs removal continues to be excellent, with decontamination factors (DF) averaging 16,400. The bulk chemistry of the DSSHT and SEHT samples do not show any signs of unusual behavior. SRNL recommends that a sample of the strip feed be analyzed for cation and anion content if a further decline in boron concentration is noted in future SEHT samples.« less

  2. Stability of athlete blood passport parameters during air freight.

    PubMed

    Ashenden, M; Sharpe, K; Plowman, J; Allbon, G; Lobigs, L; Baron, A; Gore, C J

    2014-10-01

    Fluctuations in ambient temperature and pressure, as well as physical jostling, may affect the stability of whole blood samples transported by air freight. The aim of this study was to characterize the stability of key blood variables during air freight and to investigate whether vibration or reduced pressure alone affected results. Over a 72-h interval, we evaluated the stability of full blood count indices (plus reticulocytes) in tubes that were air-freighted a total of 2, 10 and 28 h. We also examined the impact of 24 h of reduced atmospheric pressure (750 hpa or approximately 2500 m.a.s.l) and vibration (5 Hz). Samples were measured on a Sysmex XT-2000i instrument. The two key variables in the context of antidoping (haemoglobin concentration, reticulocytes) remained stable over a 72-h period regardless of the duration of air freight. Atmospheric pressure and vibration had no discernible effect. Whole blood samples stored in NanoCool devices can be relied upon to remain stable for at least 72 h despite interim air freight. © 2013 John Wiley & Sons Ltd.

  3. Meteorological and operational aspects of 46 clear air turbulence sampling missions with an instrument B-57B aircraft. Volume 1: Program summary

    NASA Technical Reports Server (NTRS)

    Davis, R. E.; Champine, R. A.; Ehernberger, L. J.

    1979-01-01

    The results of 46 clear air turbulence (CAT) probing missions conducted with an extensively instrumented B-57B aircraft are summarized. Turbulence samples were obtained under diverse conditions including mountain waves, jet streams, upper level fronts and troughs, and low altitude mechanical and thermal turbulence. CAT was encouraged on 20 flights comprising 77 data runs. In all, approximately 4335 km were flown in light turbulence, 1415 km in moderate turbulence, and 255 km in severe turbulence during the program. The flight planning, operations, and turbulence forecasting aspects conducted with the B-57B aircraft are presented.

  4. Air-coupled ultrasound: a novel technique for monitoring the curing of thermosetting matrices.

    PubMed

    Lionetto, Francesca; Tarzia, Antonella; Maffezzoli, Alfonso

    2007-07-01

    A custom-made, air-coupled ultrasonic device was applied to cure monitoring of thick samples (7-10 mm) of unsaturated polyester resin at room temperature. A key point was the optimization of the experimental setup in order to propagate compression waves during the overall curing reaction by suitable placement of the noncontact transducers, placed on the same side of the test material, in the so-called pitch-catch configuration. The progress of polymerization was monitored through the variation of the time of flight of the propagating longitudinal waves. The exothermic character of the polymerization was taken into account by correcting the measured value of time of flight with that one in air, obtained by sampling the air velocity during the experiment. The air-coupled ultrasonic results were compared with those obtained from conventional contact ultrasonic measurements. The good agreement between the air-coupled ultrasonic results and those obtained by the rheological analysis demonstrated the reliability of air-coupled ultrasound in monitoring the changes of viscoelastic properties at gelation and vitrification. The position of the transducers on the same side of the sample makes this technique suitable for on-line cure monitoring during several composite manufacturing technologies.

  5. Auditory Risk of Air Rifles

    PubMed Central

    Lankford, James E.; Meinke, Deanna K.; Flamme, Gregory A.; Finan, Donald S.; Stewart, Michael; Tasko, Stephen; Murphy, William J.

    2016-01-01

    Objective To characterize the impulse noise exposure and auditory risk for air rifle users for both youth and adults. Design Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit and LAeq75 exposure limit suggested by the World Health Organization (1999) for children. Study sample Impulses were generated by 9 pellet air rifles and 1 BB air rifle. Results None of the air rifles generated peak levels that exceeded the 140 dB peak limit for adults and 8 (80%) exceeded the 120 dB peak SPL limit for youth. In general, for both adults and youth there is minimal auditory risk when shooting less than 100 unprotected shots with pellet air rifles. Air rifles with suppressors were less hazardous than those without suppressors and the pellet air rifles with higher velocities were generally more hazardous than those with lower velocities. Conclusion To minimize auditory risk, youth should utilize air rifles with an integrated suppressor and lower velocity ratings. Air rifle shooters are advised to wear hearing protection whenever engaging in shooting activities in order to gain self-efficacy and model appropriate hearing health behaviors necessary for recreational firearm use. PMID:26840923

  6. Comparison of the Multiple-sample means with composite sample results for fecal indicator bacteria by quantitative PCR and culture

    EPA Science Inventory

    ABSTRACT: Few studies have addressed the efficacy of composite sampling for measurement of indicator bacteria by QPCR. In this study, composite results were compared to single sample results for culture- and QPCR-based water quality monitoring. Composite results for both methods ...

  7. Analysis of particle and vapour phase PAHs from the personal air samples of bus garage workers exposed to diesel exhaust.

    PubMed

    Kuusimaki, Leea; Peltonen, Kimmo; Mutanen, Pertti; Savela, Kirsti

    2003-07-01

    The levels of particle and vapour phase polycyclic aromatic hydrocarbons (PAHs) derived from the diesel exhaust compounds in bus garage work were measured in winter and in summer. Five personal air samples were collected from the breathing zones of 22 garage workers every other day of consecutive weeks. Control samples (n = 22) were collected from office workers in Helsinki. Fifteen PAHs in the air samples were analysed by HPLC using a fluorescence detector. Statistically significant differences were observed between total PAH levels of the exposed workers (2241 and 1245 ng/m(3)) and the control group (254 and 275 ng/m(3)) in both winter (P < 0.001) and summer (P < 0.001). Phenanthrene, pyrene, benzo[ghi]perylene and fluoranthene were the major compounds in the particle phase, and naphthalene, phenanthrene and fluorene in the vapour phase. About 98% of PAHs measured were related to the vapour phase compounds, whereas the high molecular weight PAH compounds were detected only in the particle phase. The PAH levels in the garages were twice as high (P < 0.001) in winter as in summer. Even though the exposure levels were low in the bus garages, the low level does not allow conclusions to be drawn about the possible adverse health effects due to exposure to diesel exhaust.

  8. An automated atmospheric sampling system operating on 747 airliners

    NASA Technical Reports Server (NTRS)

    Perkins, P. J.; Gustafsson, U. R. C.

    1976-01-01

    An air sampling system that automatically measures the temporal and spatial distribution of particulate and gaseous constituents of the atmosphere is collecting data on commercial air routes covering the world. Measurements are made in the upper troposphere and lower stratosphere (6 to 12 km) of constituents related to aircraft engine emissions and other pollutants. Aircraft operated by different airlines sample air at latitudes from the Arctic to Australia. This unique system includes specialized instrumentation, a special air inlet probe for sampling outside air, a computerized automatic control, and a data acquisition system. Air constituent and related flight data are tape recorded in flight for later computer processing on the ground.

  9. CTEPP NC DATA SUPPLEMENTAL INFORMATION ON FIELD AND LABORATORY SAMPLES

    EPA Science Inventory

    This data set contains supplemental data related to the final core analytical results table. This includes sample collection data for example sample weight, air volume, creatinine, specific gravity etc.

    The Children’s Total Exposure to Persistent Pesticides and Other Persistent...

  10. Collection and Analysis of Firn Air from the South Pole, 2001

    NASA Astrophysics Data System (ADS)

    Butler, J. H.; Montzka, S. A.; Battle, M.; Clarke, A. D.; Mondeel, D. J.; Lind, J. A.; Hall, B. D.; Elkins, J. W.

    2001-12-01

    In January 2001, we collected an archive of 20th century air from the firn (snowpack) at the South Pole. Samples were collected into separate pairs of 3L glass flasks for measurements of O2/N2 (Bowdoin/Princeton) and carbon cycle gases (CMDL); individual 3L stainless steel and glass flasks for measurements of halocarbons, N2O, SF6, and COS; large (33L) stainless steel canisters for maintaining an archive of air for future analyses; and a few canisters each for measurement of 14CH4 (NIWA/CSIRO) and very low-level analyses of SF6 (SIO). Although it was hoped to obtain air dating back to the turn of the century, the analyses suggest that the earliest date was 1925 for CO2 and the mid- to late teens for heavier gases such as methyl bromide or methyl chloride. This talk will compare the analyses of halocarbons in these recently collected samples to those of air in flasks sampled at the South Pole in 1995. We also will present some results for compounds not measured in the 1995 South Pole samples owing to a paucity of air. Measurements made of the same gases in the firn air at both ends of this six-year interval, along with real-time atmospheric measurements of the same gases, are useful in evaluating assumptions about diffusion in the firn and may allow for the direct calculation of diffusion coefficients at low temperatures. This, in turn, would improve age estimates for firn air samples. New measurements will add to our existing histories established for the 20th century from analyses of firn air samples collected in both Greenland and Antarctica.

  11. Lichen communities indicator results from Idaho: baseline sampling

    Treesearch

    Peter Neitlich; Paul Rogers; Roger Rosentreter

    2003-01-01

    Epiphytic lichen communities are included in the national Forest Health Monitoring (FHM) program because they help us assess resource contamination, biodiversity, and sustainability in the context of forest health. In 1996, field crews collected lichen samples on 141 field plots systematically located across all forest ownership groups in Idaho. Results presented here...

  12. Tilted wheel satellite attitude control with air-bearing table experimental results

    NASA Astrophysics Data System (ADS)

    Inumoh, Lawrence O.; Forshaw, Jason L.; Horri, Nadjim M.

    2015-12-01

    Gyroscopic actuators for satellite control have attracted significant research interest over the years, but their viability for the control of small satellites has only recently started to become clear. Research on variable speed gyroscopic actuators has long been focused on single gimbal actuators; double gimbal actuators typically operate at constant wheel spin rate and allow tilt angle ranges far larger than the ranges needed to operate most satellite missions. This research examines a tilted wheel, a newly proposed type of inertial actuator that can generate torques in all three principal axes of a rigid satellite using a spinning wheel and a double tilt mechanism. The tilt mechanism tilts the angular momentum vector about two axes providing two degree of freedom control, while variation of the wheel speed provides the third. The equations of motion of the system lead to a singularity-free system during nominal operation avoiding the need for complex steering logic. This paper describes the hardware design of the tilted wheel and the experimental setup behind both standalone and spherical air-bearing tables used to test it. Experimental results from the air bearing table are provided with the results depicting the high performance capabilities of the proposed actuator in torque generation.

  13. U.S. Air Force School of Aerospace Medicine Laboratory Sampling and Analysis Guide

    DTIC Science & Technology

    2016-11-15

    valuable information during the environmental health risk assessment.  EPA Integrated Risk Information System (IRIS). IRIS is a human health assessment...information for more than 550 chemical substances containing information on human health effects that may result from exposure to various substances in the...Crystalyn E. Brown November 2016 Air Force Research Laboratory 711th Human Performance Wing School of Aerospace Medicine

  14. Airtightness Results of Roof-Only Air Sealing Strategies on 1 ½-Story Homes in Cold Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ojczyk, C.; Murry, T.; Mosiman, G.

    In this second study on solutions to ice dams in 1-1/2 story homes, the NorthernSTAR Building America Partnership team analyzed five test homes located in both cold and very cold climates for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. These homes were chosen for testing as they are common in Minnesota and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach formore » whole house (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled the team to compare air tightness data from over 220 homes using similar air seal methods.« less

  15. Development and deployment of a low-cost, mobile-ready, air quality sensor system: progress toward distributed networks and autonomous aerial sampling

    NASA Astrophysics Data System (ADS)

    Hersey, S. P.; DiVerdi, R.; Gadtaula, P.; Sheneman, T.; Flores, K.; Chen, Y. H.; Jayne, J. T.; Cross, E. S.

    2017-12-01

    Throughout the 2016-2017 academic year, a new partnership between Olin College of Engineering and Aerodyne Research, Inc. developed an affordable, self-contained air quality monitoring instrument called Modulair. The Modulair instrument is based on the same operating principles as Aerodyne's newly-developed ARISense integrated sensor system, employing electrochemical sensors for gas-phase measurements of CO, NO, NO2, and O3 and an off-the-shelf optical particle counter for particle concentration, number, and size distribution information (0.4 < dp < 17 microns). High Dimensional Model Representation (HDMR) has been used to model the interference derived from relative humidity and temperature as well as the cross-sensitivity of the electrochemical sensors to non-target gas-phase species. The aim of the modeling effort is to provide transparent and robust calibration of electrical signals to pollutant concentrations from a set of electrochemical sensors. Modulair was designed from the ground-up, with custom electronics - including a more powerful microcontroller, a fully re-designed housing and a device-specific backend with a mobile, cloud-based data management system for real-time data posting and analysis. Open source tools and software were utilized in the development of the instrument. All initial work was completed by a team of undergraduate students as part of the Senior Capstone Program in Engineering (SCOPE) at Olin College. Deployment strategies for Modulair include distributed, mobile measurements and drone-based aerial sampling. Design goals for the drone integration include maximizing airborne sampling time and laying the foundation for software integration with the drone's autopilot system to allow for autonomous plume sampling across concentration gradients. Modulair and its flexible deployments enable real-time mapping of air quality data at exposure-relevant spatial scales, as well as regular, autonomous characterization of sources and dispersion of

  16. [Implementation results of emission standards of air pollutants for thermal power plants: a numerical simulation].

    PubMed

    Wang, Zhan-Shan; Pan, Li-Bo

    2014-03-01

    The emission inventory of air pollutants from the thermal power plants in the year of 2010 was set up. Based on the inventory, the air quality of the prediction scenarios by implementation of both 2003-version emission standard and the new emission standard were simulated using Models-3/CMAQ. The concentrations of NO2, SO2, and PM2.5, and the deposition of nitrogen and sulfur in the year of 2015 and 2020 were predicted to investigate the regional air quality improvement by the new emission standard. The results showed that the new emission standard could effectively improve the air quality in China. Compared with the implementation results of the 2003-version emission standard, by 2015 and 2020, the area with NO2 concentration higher than the emission standard would be reduced by 53.9% and 55.2%, the area with SO2 concentration higher than the emission standard would be reduced by 40.0%, the area with nitrogen deposition higher than 1.0 t x km(-2) would be reduced by 75.4% and 77.9%, and the area with sulfur deposition higher than 1.6 t x km(-2) would be reduced by 37.1% and 34.3%, respectively.

  17. Sampling model of government travel vouchers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, P.S.; Wright, T.

    1987-02-01

    A pilot survey was designed and executed to better understand the structure of the universe of all government travel vouchers. Thirteen civilian and military sites were selected for the pilot survey. A total of 3916 travel vouchers with attached tickets were sampled. During the course of the pilot survey, it was felt that the compounding problems of the relative rarity of the expired, unused tickets and the enormously huge universe were too much of an obstacle to overcome in sampling the entire universe (including the US Air Force, US Army, US Navy, US Marines, other Department of Defense offices, andmore » civil) in the first year. The universe was then narrowed to the US Air Force, and US Army which have to two largest government travel expenditures. Based on the results of the pilot survey, ORNL recommends a stratified two-stage cluster sampling model. With probability of 0.90, a sample of size 78 (sites) will be needed to estimate the amounts per airline which will not be more than $50,000 from the true values. This sampling model allows one to estimate the total dollar amounts of expired, unused tickets for individual airlines.« less

  18. CTEPP-OH DATA SUPPLEMENTAL INFORMATION ON FIELD AND LABORATORY SAMPLES

    EPA Science Inventory

    This data set contains supplemental data related to the final core analytical results table for CTEPP-OH. This includes sample collection data for example sample weight, air volume, creatinine, specific gravity etc.

    The Children’s Total Exposure to Persistent Pesticides and Oth...

  19. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF AIR SAMPLES FOR GC/MS ANALYSIS OF PESTICIDE AND PAH (BCO-L-27.0)

    EPA Science Inventory

    The purpose of this SOP is to describe methods for extracting and preparing an air sample consisting of a quartz fiber filter (Pallflex) and an XAD-2 cartridge for analysis of pesticides and polyaromatic hydrocarbons (PAHs). It covers the preparation of samples that are to be an...

  20. Geospatial relationships of air pollution and acute asthma events across the Detroit-Windsor international border: study design and preliminary results.

    PubMed

    Lemke, Lawrence D; Lamerato, Lois E; Xu, Xiaohong; Booza, Jason C; Reiners, John J; Raymond Iii, Delbert M; Villeneuve, Paul J; Lavigne, Eric; Larkin, Dana; Krouse, Helene J

    2014-07-01

    The Geospatial Determinants of Health Outcomes Consortium (GeoDHOC) study investigated ambient air quality across the international border between Detroit, Michigan, USA and Windsor, Ontario, Canada and its association with acute asthma events in 5- to 89-year-old residents of these cities. NO2, SO2, and volatile organic compounds (VOCs) were measured at 100 sites, and particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) at 50 sites during two 2-week sampling periods in 2008 and 2009. Acute asthma event rates across neighborhoods in each city were calculated using emergency room visits and hospitalizations and standardized to the overall age and gender distribution of the population in the two cities combined. Results demonstrate that intra-urban air quality variations are related to adverse respiratory events in both cities. Annual 2008 asthma rates exhibited statistically significant positive correlations with total VOCs and total benzene, toluene, ethylbenzene and xylene (BTEX) at 5-digit zip code scale spatial resolution in Detroit. In Windsor, NO2, VOCs, and PM10 concentrations correlated positively with 2008 asthma rates at a similar 3-digit postal forward sortation area scale. The study is limited by its coarse temporal resolution (comparing relatively short term air quality measurements to annual asthma health data) and interpretation of findings is complicated by contrasts in population demographics and health-care delivery systems in Detroit and Windsor.

  1. Symptomatic effects of exposure to diluted air sampled from a swine confinement atmosphere on healthy human subjects.

    PubMed

    Schiffman, Susan S; Studwell, Clare E; Landerman, Lawrence R; Berman, Katherine; Sundy, John S

    2005-05-01

    Aerial emissions from a swine house at North Carolina State University's field laboratory were diluted to a level that could occur at varying distances downwind from a confined animal feeding operation (CAFO) both within and beyond the property line, and these emissions were delivered to an environmental exposure chamber. The study design consisted of two 1-hr sessions, one in which 48 healthy human adult volunteers were exposed to diluted swine air and another in which they were exposed to clean air (control). Objective measures of blood pressure, temperature, heart rate, respiratory rate, lung function, nasal inflammation, secretory immunity, mood, attention, and memory were correlated with objective measures of air quality. Ratings of perceived (self-reported) health symptoms were also obtained. The mean levels of airborne constituents in the swine air condition were hydrogen sulfide (24 ppb), ammonia (817 ppb), total suspended particulates (0.0241 mg/m3), endotoxin (7.40 endotoxin units/m3), and odor (57 times above odor threshold). No statistical differences on objective measures of physical symptoms, mood, or attention resulted from the 1-hr exposure to swine emissions in the environmental chamber when compared with clean air for healthy human volunteers. However, subjects were 4.1 (p = 0.001) times more likely to report headaches, 6.1 (p = 0.004) times more likely to report eye irritation, and 7.8 (p = 0.014) times more likely to report nausea in the swine air (experimental) condition than in the control condition. These results indicate that short-term exposure in an environmental chamber to malodorous emissions from a swine house at levels expected downwind can induce clinically important symptoms in healthy human volunteers.

  2. RELATIVE CONGENER SCALING OF POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS TO ESTIMATE BUILDING FIRE CONTRIBUTIONS IN AIR, SURFACE WIPES, AND DUST SAMPLES

    EPA Science Inventory

    EPA collected ambient air samples in lower Manhattan for about nine months following the September 11, 2001 (9/11) World Trade Center (WTC) attacks. Measurements were made of a host of airborne contaminants including volatile organic compounds (VOCs), polycyclic aromatic hydroca...

  3. Air-Based Remediation Workshop - Section 1 Sampling And Analysis Revelant To Air-Based Remediation Technologies

    EPA Science Inventory

    Pursant to the EPA-AIT Implementing Arrangement 7 for Technical Environmental Collaboration, Activity 11 "Remediation of Contaminated Sites," the USEPA Office of International Affairs Organized a Force Air Remediation Workshop in Taipei to deliver expert training to the Environme...

  4. Development and testing of a portable wind sensitive directional air sampler

    NASA Technical Reports Server (NTRS)

    Deyo, J.; Toma, J.; King, R. B.

    1975-01-01

    A portable wind sensitive directional air sampler was developed as part of an air pollution source identification system. The system is designed to identify sources of air pollution based on the directional collection of field air samples and their analysis for TSP and trace element characteristics. Sources can be identified by analyzing the data on the basis of pattern recognition concepts. The unit, designated Air Scout, receives wind direction signals from an associated wind vane. Air samples are collected on filter slides using a standard high volume air sampler drawing air through a porting arrangement which tracks the wind direction and permits collection of discrete samples. A preset timer controls the length of time each filter is in the sampling position. At the conclusion of the sampling period a new filter is automatically moved into sampling position displacing the previous filter to a storage compartment. Thus the Air Scout may be set up at a field location, loaded with up to 12 filter slides, and left to acquire air samples automatically, according to the wind, at any timer interval desired from 1 to 30 hours.

  5. [Microbiological quality of the air in "small gastronomy point"].

    PubMed

    Wójcik-Stopczyńska, Barbara

    2006-01-01

    The aim of this work was the estimation of microbial contamination of the air in "small gastronomy point". The study included three places, which have been separated on the ground of their function: 1. area of subsidiaries, 2. area of distribution (sale and serving meal), 3. area of consumption. The total numbers of aerobic mesophilic bacteria, yeasts and moulds were determined by sedimentation method. Taxonomy units of fungal aerosol were also estimated. The samples of air were collected in 16 investigation points in the morning (8-8.30) and in the afternoon (14-14.30). Four series of measurements were carried out and in general 128 of air samples were tested. The results showed that numbers of bacteria, yeasts and moulds were variable and received respectively 30-3397, 0-254 and 0-138 cfu x m(-3). Microbial contamination of air changed depending on area character (the highest average count of bacteria occurred in the air of consumption area and fungi in subsidiaries area), time of a day (contamination of the air increased in the afternoon) and determination date. Only in single samples the numbers of bacteria and fungi were higher than recommended level. Pigmentary bacteria had high participation in total count of bacteria and filamentous fungi were represented mostly by Penicillium sp. and Cladosporium sp.

  6. Investigation of Air Quality Problems in an Indoor Swimming Pool: A Case Study.

    PubMed

    Lévesque, Benoit; Vézina, Lorraine; Gauvin, Denis; Leroux, Patrice

    2015-10-01

    Trichloramine (NCl3) is the contaminant suspected the most to cause irritative respiratory symptoms among swimmers and swimming pool workers. Following complaints by employees working in an indoor swimming pool, this study set out to identify the determinants of NCl3 air concentrations in that particular swimming pool. To document NCl3 air levels, air samples (n = 26) were collected once or twice a day for 3 h, at least 3 days per week, between October and December 2011. Water samples were taken three times during air sampling to verify free chlorine, chloramines, alkalinity, conductivity, pH, water temperature, and turbidity. Water changes were also recorded, along with the number of bathers. Ventilation (outdoor air flow) was modified to verify the influence of this important variable. Data were evaluated by analysis of variance. Mean NCl3 air concentration was 0.38 mg m(-3). The best model explaining variations of NCl3 air levels (r2 = 0.83) included sampling period (P = 0.002, NCl3 was higher in the evening versus the morning), water changes (P = 0.02, NCl3 was lower with water changes between 60 and 90 min day(-1) versus <60 min day(-1)), and ventilation (P = 0.0002, NCl3 was lower with ≥2 air changes per hour (ACH) versus <1 ACH). Although based on only 26 air samples, our results indicate that ventilation is an important determinant of NCl3 air concentration in swimming pool air. There is limited information available on the air quality of indoor swimming pools and the relationship with ventilation. Efforts are needed to document the situation and to develop state-of-the-art facilities for ventilation of indoor swimming pools. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  7. Assessment of POPs in air from Spain using passive sampling from 2008 to 2015. Part II: Spatial and temporal observations of PCDD/Fs and dl-PCBs.

    PubMed

    Muñoz-Arnanz, Juan; Roscales, Jose L; Vicente, Alba; Ros, María; Barrios, Laura; Morales, Laura; Abad, Esteban; Jiménez, Begoña

    2018-09-01

    Time series (2008-2015) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in ambient air from the Spanish Monitoring Program were analyzed. A total of 321 samples were collected seasonally each year in 5 urban and 7 background sites by means of passive air sampling. Air concentrations were higher at urban than background sites (urban vs. background concentration ranges): PCDD/Fs (26.9-1010 vs. 20.0-357 fg/m 3 ), non-ortho PCBs (0.113-3.14 vs. 0.042-2.00 pg/m 3 ) and mono-ortho PCBs (0.644-41.3 vs. 0.500-32.8 pg/m 3 ). Results showed significant decreases from 2009 for non-ortho PCBs and PCDD/Fs as well as for WHO 2006 -TEQs. These declines were sharper, and sometimes only significant, in urban places resulting in converging levels at urban and background sites for these pollutants at the end of the study period. In contrast, mono-ortho PCBs did not show any significant variation but a steady flat temporal behavior in their concentrations, suggesting the existence of different sources between mono-ortho and non-ortho PCBs. Seasonality was observed for air burdens of all these POPs. PCDD/Fs were mostly measured at higher concentrations in colder than in hot seasons, and the opposite was true for dl-PCBs. Seasonal variations for PCDD/Fs appeared to be related to changes in their sources (e.g. domestic heating, open burning) rather than to temperature per se. In contrast, environmental temperature dependent factors (e.g. increased partitioning into the gas phase) drove seasonal variations in dl-PCBs instead of seasonal changes in their sources. Regarding spatial patterns, significant greater levels of PCDD/Fs and dl-PCBs were generally found in cities compared to background areas, pointing out the role of densely populated areas as sources for these pollutants in Spain. As proven by our results, long-term monitoring activities are essential to assess and understand temporal behaviors for these

  8. Quality Control for Ambient Sampling of PCDD/PCDF from Open Combustion Sources

    EPA Science Inventory

    Both long duration (> 6 h) and high temperature (up to 139o C) sampling efforts were conducted using ambient air sampling methods to determine if either high volume throughput or higher than ambient sampling temperatures resulted in loss of target polychlorinated dibenzodioxins/d...

  9. Fungal Communities Including Plant Pathogens in Near Surface Air Are Similar across Northwestern Europe.

    PubMed

    Nicolaisen, Mogens; West, Jonathan S; Sapkota, Rumakanta; Canning, Gail G M; Schoen, Cor; Justesen, Annemarie F

    2017-01-01

    Information on the diversity of fungal spores in air is limited, and also the content of airborne spores of fungal plant pathogens is understudied. In the present study, a total of 152 air samples were taken from rooftops at urban settings in Slagelse, DK, Wageningen NL, and Rothamsted, UK together with 41 samples from above oilseed rape fields in Rothamsted. Samples were taken during 10-day periods in spring and autumn, each sample representing 1 day of sampling. The fungal content of samples was analyzed by metabarcoding of the fungal internal transcribed sequence 1 (ITS1) and by qPCR for specific fungi. The metabarcoding results demonstrated that season had significant effects on airborne fungal communities. In contrast, location did not have strong effects on the communities, even though locations were separated by up to 900 km. Also, a number of plant pathogens had strikingly similar patterns of abundance at the three locations. Rooftop samples were more diverse than samples taken above fields, probably reflecting greater mixing of air from a range of microenvironments for the rooftop sites. Pathogens that were known to be present in the crop were also found in air samples taken above the field. This paper is one of the first detailed studies of fungal composition in air with the focus on plant pathogens and shows that it is possible to detect a range of pathogens in rooftop air samplers using metabarcoding.

  10. Inter-conversion of Chromium Species During Air Sampling: Effects of O3, NO2, SO2, Particle Matrices, Temperature and Humidity

    PubMed Central

    Huang, Lihui; Fan, Zhihua (Tina); Yu, Chang Ho; Hopke, Philip K.; Lioy, Paul J.; Buckley, Brian T.; Lin, Lin; Ma, Yingjun

    2013-01-01

    The inter-conversion between Cr(VI), a pulmonary carcinogen, and Cr(III), an essential human nutrient, poses challenges to the measurement of Cr(VI) in airborne particles. Chamber and field tests were conducted to identify the factors affecting Cr(VI)-Cr(III) inter-conversion in the basic filter medium under typical sampling conditions. In the chamber tests, isotopically enriched 53Cr(VI) and 50Cr(III) were spiked on diesel particulate matter (DPM) and secondary organic aerosol (SOA) that were pre-collected on a basic MCE filter. The filter samples were then exposed to clean air or the air containing SO2 (50 and 160 ppb), 100 ppb O3, or 150 ppb NO2 for 24 hours at 16.7 LPM flow rate at designated temperature (20 and 31°C) and RH (40% and 70%) conditions. Exposure to 160 ppb SO2 had the greatest effect on 53Cr(VI) reduction, with 53Cr(VI) recovery of 31.7 ± 15.8% (DPM) and 42.0 ± 7.9% (SOA). DPM and SOA matrix induced 53Cr(VI) reduction when exposed to clean air while reactive oxygen species in SOA could promote 50Cr(III) oxidation. Deliquescence when RH increased from 40% to 70% led to conversion of Cr(III) in SOA, whereas oxidized organics in DPM and SOA enhanced hygroscopicity and thus facilitated Cr(VI) reduction. Field tests showed seasonal variation of Cr(VI)-Cr(III) inter-conversion during sampling. Correction of the inter-conversion using USEPA method 6800 is recommended to improve accuracy of ambient Cr(VI) measurements. PMID:23550818

  11. GICHD Mine Dog Testing Project - Soil Sample Results No.3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    PHELAN, JAMES M.; BARNETT, JAMES L.; BENDER, SUSAN FAE ANN

    2003-03-01

    A mine dog evaluation project initiated by the Geneva International Center for Humanitarian Demining is evaluating the capability and reliability of mine detection dogs. The performance of field-operational mine detection dogs will be measured in test minefields in Afghanistan and Bosnia containing actual, but unfused landmines. Repeated performance testing over two years through various seasonal weather conditions will provide data simulating near real world conditions. Soil samples will be obtained adjacent to the buried targets repeatedly over the course of the test. Chemical analysis results from these soil samples will be used to evaluate correlations between mine dog detection performancemore » and seasonal weather conditions. This report documents the analytical chemical methods and results from the third batch of soils received. This batch contained samples from Kharga, Afghanistan collected in October 2002.« less

  12. Characterization of 41Ar production in air at a PET cyclotron facility

    NASA Astrophysics Data System (ADS)

    Cicoria, Gianfranco; Cesarini, Francesco; Infantino, Angelo; Vichi, Sara; Zagni, Federico; Marengo, Mario

    2017-06-01

    In the production of Positron Emission Tomography (PET) nuclides at a medical cyclotron facility 41Ar (T1/2 = 109.34 m) is produced by the activation of air due to the neutron flux, according to the 40Ar(n, γ)41Ar reaction. In this work, we describe a relatively inexpensive and readily reproducible methodology of air sampling that can be used for quantification of 41Ar during the routine production of PET nuclides. We report the results of an extensive measurement campaign in the cyclotron bunker and in the ducts of the ventilation system, before and after final filtering of the extracted air. Air Samples were analyzed using a gamma-ray spectrometry system equipped with HPGe detector, with proper correction of the efficiency calibration to account for the samples density. The results of measurement were then used to evaluate the Total Effective Dose (TED) to the population living in the surrounding areas, due to routine emissions in the operation of the cyclotron. The average 41Ar saturation yield per one liter of air emitted in the environment resulted to be (0.044 ± 0.007) Bq/(μA ṡ dm3). The maximum value of TED for the critical group of the population, even considering an overestimated workload, was less than 0.19 μSv/year, well below the level of radiological relevance.

  13. A BATTERY-OPERATED AIR SAMPLER FOR REMOTE AREAS

    EPA Science Inventory

    An air sampling system developed to evaluate air quality in biosphere reserves or in other remote areas is described. The equipment consists of a Dupont P-4000 pump and a specially designed battery pack containing Gates batteries. This air sampling system was tested in Southern U...

  14. Comparing the VOC emissions between air-dried and heat-treated Scots pine wood

    NASA Astrophysics Data System (ADS)

    Manninen, Anne-Marja; Pasanen, Pertti; Holopainen, Jarmo K.

    The emissions of volatile organic compounds (VOCs) from air-dried Scots pine wood and from heat-treated Scots pine wood were compared with GC-MS analysis. Air-dried wood blocks released about 8 times more total VOCs than heat-treated (24 h at 230°C) ones. Terpenes were clearly the main compound group in the air-dried wood samples, whereas aldehydes and carboxylic acids and their esters dominated in the heat-treated wood samples. Only 14 compounds out of 41 identified individual compounds were found in both wood samples indicating considerable changes in VOC emission profile during heat-treatment process. Of individual compounds α-pinene, 3-carene and hexanal were the most abundant ones in the air-dried wood. By contrast, in the heat-treated wood 2-furancarboxaldehyde, acetic acid and 2-propanone were the major compounds of VOC emission. Current emission results reveal that significant chemical changes have occurred, and volatile monoterpenes and other low-molecular-weight compounds have evaporated from the wood during the heat-treatment process when compared to air-dried wood. Major chemical changes detected in VOC emissions are explained by the thermal degradation and oxidation of main constituents in wood. The results suggest that if heat-treated wood is used in interior carpentry, emissions of monoterpenes are reduced compared to air-dried wood, but some irritating compounds might be released into indoor air.

  15. Saharan dust particles in snow samples of Alps and Apennines during an exceptional event of transboundary air pollution.

    PubMed

    Telloli, Chiara; Chicca, Milvia; Pepi, Salvatore; Vaccaro, Carmela

    2017-12-21

    Southern European countries are often affected in summer by transboundary air pollution from Saharan dust. However, very few studies deal with Saharan dust pollution at high altitudes in winter. In Italy, the exceptional event occurred on February 19, 2014, colored in red the entire mountain range (Alps and Apennines) and allowed to characterize the particulate matter deposited on snow from a morphological and chemical point of view. Snow samples were collected after this event in four areas in the Alps and one in the Apennines. The particulate matter of the melted snow samples was analyzed by scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) and by inductively coupled plasma mass spectrometry (ICP-MS). These analyses confirmed the presence of Saharan dust particle components in all areas with similar percentages, supported also by the positive correlations between Mg-Ca, Al-Ca, Al-Mg, and Al-K in all samples.

  16. Development and validation of a sensitive thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method for the determination of phosgene in air samples.

    PubMed

    Juillet, Y; Dubois, C; Bintein, F; Dissard, J; Bossée, A

    2014-08-01

    A new rapid, sensitive and reliable method was developed for the determination of phosgene in air samples using thermal desorption (TD) followed by gas chromatography-mass spectrometry (GC-MS). The method is based on a fast (10 min) active sampling of only 1 L of air onto a Tenax® GR tube doped with 0.5 mL of derivatizing mixture containing dimercaptotoluene and triethylamine in hexane solution. Validation of the TD-GC-MS method showed a low limit of detection (40 ppbv), acceptable repeatability, intermediate fidelity (relative standard deviation within 12 %) and excellent accuracy (>95%). Linearity was demonstrated for two concentration ranges (0.04 to 2.5 ppmv and 2.5 to 10 ppmv) owing to variation of derivatization recovery between low and high concentration levels. Due to its simple on-site implementation and its close similarity with recommended operating procedure (ROP) for chemical warfare agents vapour sampling, the method is particularly useful in the process of verification of the Chemical Weapons Convention.

  17. Carbapenem-Resistant Acinetobacter baumannii: Concomitant Contamination of Air and Environmental Surfaces.

    PubMed

    Shimose, Luis A; Masuda, Eriko; Sfeir, Maroun; Berbel Caban, Ana; Bueno, Maria X; dePascale, Dennise; Spychala, Caressa N; Cleary, Timothy; Namias, Nicholas; Kett, Daniel H; Doi, Yohei; Munoz-Price, L Silvia

    2016-07-01

    OBJECTIVE To concomitantly determine the differential degrees of air and environmental contamination by Acinetobacter baumannii based on anatomic source of colonization and type of ICU layout (single-occupancy vs open layout). DESIGN Longitudinal prospective surveillance study of air and environmental surfaces in patient rooms. SETTING A 1,500-bed public teaching hospital in Miami, Florida. PATIENTS Consecutive A. baumannii-colonized patients admitted to our ICUs between October 2013 and February 2014. METHODS Air and environmental surfaces of the rooms of A. baumannii-colonized patients were sampled daily for up to 10 days. Pulsed-field gel electrophoresis (PFGE) was used to type and match the matching air, environmental, and clinical A. baumannii isolates. RESULTS A total of 25 A. baumannii-colonized patients were identified during the study period; 17 were colonized in the respiratory tract and 8 were colonized in the rectum. In rooms with rectally colonized patients, 38.3% of air samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 13.1% of air samples were positive (P=.0001). In rooms with rectally colonized patients, 15.5% of environmental samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 9.5% of environmental samples were positive (P=.02). The rates of air contamination in the open-layout and single-occupancy ICUs were 17.9% and 21.8%, respectively (P=.5). Environmental surfaces were positive in 9.5% of instances in open-layout ICUs versus 13.4% in single-occupancy ICUs (P=.09). CONCLUSIONS Air and environmental surface contaminations were significantly greater among rectally colonized patients; however, ICU layout did not influence the rate of contamination. Infect Control Hosp Epidemiol 2016;37:777-781.

  18. Historic CH4 Records from Antarctic and Greenland Ice Cores, Antarctic Firn Data, and Archived Air Samples from Cape Grim, Tasmania

    DOE Data Explorer

    Etheridge, D. M. [Division of Atmospheric Research, CSIRO, Aspendale, Victoria, Australia; Steele, L. P. [Division of Atmospheric Research, CSIRO, Aspendale, Victoria, Australia; Francey, R. J. [Division of Atmospheric Research, CSIRO, Aspendale, Victoria, Australia; Langenfelds, R. L. [Division of Atmospheric Research, CSIRO, Aspendale, Victoria, Australia

    2002-01-01

    The Antarctic CH4 records presented here are derived from three ice cores obtained at Law Dome, East Antarctica (66°44'S, 112°50'E, 1390 meters above mean sea level). Law Dome has many qualities of an ideal ice core site for the reconstruction of past concentrations of atmospheric gases; these qualities include: negligible melting of the ice sheet surface, low concentrations of impurities, regular stratigraphic layering undisturbed by wind stress at the surface or differential ice flow at depth, and a high snow accumulation rate. Further details on the site, drilling, and cores are provided by Etheridge et al. (1998), Etheridge et al. (1996), Etheridge and Wookey (1989), and Morgan et al. (1997). The two Greenland ice cores are from the Summit region (72°34' N, 37°37' W, 3200 meters above mean sea level). Lower snow accumulation rate there results in lower air-age resolution, and measurements presented here cover only the pre-industrial period (until 1885). More details about these measurements are presented in Etheridge et al. (1998). Additionally, this site contains firn data from Core DE08-2, and archived air samples from Cape Grim, Tasmania, for comparison.

  19. PM2.5 Monitors in New England | Air Quality Planning Unit ...

    EPA Pesticide Factsheets

    2017-04-10

    The New England states are currently operating a network of 58 ambient PM2.5 air quality monitors that meet EPA's Federal Reference Method (FRM) for PM2.5, which is necessary in order for the resultant data to be used for attainment/non-attainment purposes. These monitors collect particles in the ambient air smaller than 2.5 microns in size on a filter, which is weighed prior and post sampling to produce a 24-hour sample concentration.

  20. Air pollution "holiday effect" resulting from the Chinese New Year

    NASA Astrophysics Data System (ADS)

    Tan, Pei-Hua; Chou, Chia; Liang, Jing-Yi; Chou, Charles C.-K.; Shiu, Chein-Jung

    Our study was an attempt to conduct a comprehensive and systematical examination of the holiday effect, defined as the difference in air pollutant concentrations between holiday and non-holiday periods. This holiday effect can be applied to other countries with similar national or cultural holidays. Hourly and daily surface measurements of six major air pollutants from thirteen air quality monitoring stations of the Taiwan Environmental Protection Administration during the Chinese New Year (CNY) and non-Chinese New Year (NCNY) periods were used. We documented evidence of a "holiday effect", where air pollutant concentrations were significantly different between holidays (CNY) and non-holidays (NCNY), in the Taipei metropolitan area over the past thirteen years (1994-2006). The concentrations of NO x, CO, NMHC, SO 2 and PM 10 were lower in the CNY than in the NCNY period, while the variation in the concentration of O 3 was reversed, which was mainly due to the NO titration effect. Similar differences in these six air pollutants between the CNY and NCNY periods were also found in the diurnal cycle and in the interannual variation. For the diurnal cycle, a common traffic-related double-peak variation was observed in the NCNY period, but not in the CNY period. Impacts of dust storms were also observed, especially on SO 2 and PM 10 in the CNY period. In the 13-year period of 1994-2006, decreasing trends of NO x and CO in the NCNY period implied a possible reduction of local emissions. Increasing trends of SO 2 and PM 10 in the CNY period, on the other hand, indicated a possible enhancement of long-range transport. These two mechanisms weakened the holiday effect.

  1. Air volume measurement of 'Braeburn' apple fruit.

    PubMed

    Drazeta, Lazar; Lang, Alexander; Hall, Alistair J; Volz, Richard K; Jameson, Paula E

    2004-05-01

    The radial disposition of air in the flesh of fruit of Malus domestica Borkh., cv 'Braeburn' was investigated using a gravimetric technique based on Archimedes' principle. Intercellular air volume was measured by weighing a small tissue sample under water before and after vacuum infiltration to remove the air. In a separate procedure, the volume of the same sample was measured by recording the buoyant upthrust experienced by it when fully immersed in water. The method underestimates tissue air volume due to a slight invasion of the intercellular air spaces around the edges of the sample when it is immersed in water. To correct for this error, an adjustment factor was made based upon an analysis of a series of measurements of air volume in samples of different dimensions. In 'Braeburn' there is a gradient of declining air content from just beneath the skin to the centre of the fruit with a sharp discontinuity at the core line. Cell shape and cell packing were observed in the surface layers of freshly excised and stained flesh samples using a dissecting microscope coupled to a video camera and a PC running proprietary software. Tissue organization changed with distance below the skin. It is speculated that reduced internal gas movement, due to the tightly packed tissue of 'Braeburn' and to the potential diffusion barrier at the core line between the cortex and the pith, may increase susceptibility of the flesh to disorders associated with tissue browning and breakdown.

  2. Development of a unique multi-contaminant air sampling device for a childhood asthma cohort in an agricultural environment.

    PubMed

    Armstrong, Jenna L; Fitzpatrick, Cole F; Loftus, Christine T; Yost, Michael G; Tchong-French, Maria; Karr, Catherine J

    2013-09-01

    This research describes the design, deployment, performance, and acceptability of a novel outdoor active air sampler to provide simultaneous measurements of multiple contaminants at timed intervals for the Aggravating Factors of Asthma in Rural Environment (AFARE) study-a longitudinal cohort of 50 children in Yakima Valley, Washington. The sampler was constructed of multiple sampling media connected to individual critical orifices and a rotary vane vacuum pump. It was connected to a timed control valve system to collect 24 hours samples every six days over 18 months. We describe a spatially representative approach with both quantitative and qualitative location criteria to deploy a network of 14 devices at participant residences in a rural region (20 × 60 km). Overall the sampler performed well, as the concurrent mean sample flow rates were within or above the ranges of recommended sampling rates for each exposure metric of interest. Acceptability was high among the study population of Hispanic farmworker participant households. The sampler design may prove useful for future urban and rural community-based studies with aims at collecting multiple contaminant data during specific time periods.

  3. Air toxics concentrations, source identification, and health risks: An air pollution hot spot in southwest Memphis, TN

    NASA Astrophysics Data System (ADS)

    Jia, Chunrong; Foran, Jeffery

    2013-12-01

    Southwest Memphis is a residential region surrounded by fossil fuel burning, steel, refining, and food processing industries, and considerable mobile sources whose emissions may pose adverse health risks to local residents. This study characterizes cancer and non-cancer risks resulting from exposure to ambient air toxics in southwest Memphis. Air toxics samples were collected at a central location every 6 days from June 5, 2008 to January 8, 2010. Volatile organic compounds (VOCs) were collected in evacuated stainless-steel canisters and aldehydes by DNPH cartridges, and samples were analyzed for 73 target compounds. A total of 60 compounds were detected and 39 were found in over 86% of the samples. Mean concentrations of many compounds were higher than those measured in many industrial communities throughout the U.S. The cumulative cancer risk associated with exposure to 13 carcinogens found in southwest Memphis air was 2.3 × 10-4, four times higher than the national average of 5.0 × 10-5. Three risk drivers were identified: benzene, formaldehyde, and acrylonitrile, which contributed 43%, 19%, and 14% to the cumulative risk, respectively. This is the first field study to confirm acrylonitrile as a potential risk driver. Mobile, secondary, industrial, and background sources contributed 57%, 24%, 14%, and 5% of the risk, respectively. The results of this study indicate that southwest Memphis, a region of significant income, racial, and social disparities, is also a region under significant environmental stress compared with surrounding areas and communities.

  4. Uncertainties in Air Exchange using Continuous-Injection, Long-Term Sampling Tracer-Gas Methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sherman, Max H.; Walker, Iain S.; Lunden, Melissa M.

    2013-12-01

    The PerFluorocarbon Tracer (PFT) method is a low-cost approach commonly used for measuring air exchange in buildings using tracer gases. It is a specific application of the more general Continuous-Injection, Long-Term Sampling (CILTS) method. The technique is widely used but there has been little work on understanding the uncertainties (both precision and bias) associated with its use, particularly given that it is typically deployed by untrained or lightly trained people to minimize experimental costs. In this article we will conduct a first-principles error analysis to estimate the uncertainties and then compare that analysis to CILTS measurements that were over-sampled, throughmore » the use of multiple tracers and emitter and sampler distribution patterns, in three houses. We find that the CILTS method can have an overall uncertainty of 10-15percent in ideal circumstances, but that even in highly controlled field experiments done by trained experimenters expected uncertainties are about 20percent. In addition, there are many field conditions (such as open windows) where CILTS is not likely to provide any quantitative data. Even avoiding the worst situations of assumption violations CILTS should be considered as having a something like a ?factor of two? uncertainty for the broad field trials that it is typically used in. We provide guidance on how to deploy CILTS and design the experiment to minimize uncertainties.« less

  5. Low concentrations of persistent organic pollutants (POPs) in air at Cape Verde.

    PubMed

    Nøst, Therese Haugdahl; Halse, Anne Karine; Schlabach, Martin; Bäcklund, Are; Eckhardt, Sabine; Breivik, Knut

    2018-01-15

    Ambient air is a core medium for monitoring of persistent organic pollutants (POPs) under the Stockholm Convention and is used in studies of global transports of POPs and their atmospheric sources and source regions. Still, data based on active air sampling remain scarce in many regions. The primary objectives of this study were to (i) monitor concentrations of selected POPs in air outside West Africa, and (ii) to evaluate potential atmospheric processes and source regions affecting measured concentrations. For this purpose, an active high-volume air sampler was installed on the Cape Verde Atmospheric Observatory at Cape Verde outside the coast of West Africa. Sampling commenced in May 2012 and 43 samples (24h sampling) were collected until June 2013. The samples were analyzed for selected polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB) and chlordanes. The concentrations of these POPs at Cape Verde were generally low and comparable to remote sites in the Arctic for several compounds. Seasonal trends varied between compounds and concentrations exhibited strong temperature dependence for chlordanes. Our results indicate net volatilization from the Atlantic Ocean north of Cape Verde as sources of these POPs. Air mass back trajectories demonstrated that air masses measured at Cape Verde were generally transported from the Atlantic Ocean or the North African continent. Overall, the low concentrations in air at Cape Verde were likely explained by absence of major emissions in areas from which the air masses originated combined with depletion during long-range atmospheric transport due to enhanced degradation under tropical conditions (high temperatures and concentrations of hydroxyl radicals). Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  6. BP Spill Sampling and Monitoring Data

    EPA Pesticide Factsheets

    This dataset analyzes waste from the the British Petroleum Deepwater Horizon Rig Explosion Emergency Response, providing opportunity to query data sets by metadata criteria and find resulting raw datasets in CSV format.The data query tool allows users to download EPA's air, water and sediment sampling and monitoring data that has been collected in response to the BP oil spill. All sampling and monitoring data that has been collected to date is available for download as raw structured data.The query tools enables CSV file creation to be refined based on the following search criteria: date range (between April 28, 2010 and 9/29/2010); location by zip, city, or county; media (solid waste, weathered oil, air, surface water, liquid waste, tar, sediment, water); substance categories (based on media selection) and substances (based on substance category selection).

  7. 40 CFR 61.34 - Air sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... filters, or for replacement of equipment needing major repair. (c) Filters shall be analyzed and concentrations calculated within 30 days after filters are collected. Records of concentrations at all sampling...

  8. 40 CFR 61.34 - Air sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... filters, or for replacement of equipment needing major repair. (c) Filters shall be analyzed and concentrations calculated within 30 days after filters are collected. Records of concentrations at all sampling...

  9. Gaseous and Freely-Dissolved PCBs in the Lower Great Lakes Based on Passive Sampling: Spatial Trends and Air-Water Exchange.

    PubMed

    Liu, Ying; Wang, Siyao; McDonough, Carrie A; Khairy, Mohammed; Muir, Derek C G; Helm, Paul A; Lohmann, Rainer

    2016-05-17

    Polyethylene passive sampling was performed to quantify gaseous and freely dissolved polychlorinated biphenyls (PCBs) in the air and water of Lakes Erie and Ontario during 2011-2012. In view of differing physical characteristics and the impacts of historical contamination by PCBs within these lakes, spatial variation of PCB concentrations and air-water exchange across these lakes may be expected. Both lakes displayed statistically similar aqueous and atmospheric PCB concentrations. Total aqueous concentrations of 29 PCBs ranged from 1.5 pg L(-1) in the open lake of Lake Erie (site E02) in 2011 spring to 105 pg L(-1) in Niagara (site On05) in 2012 summer, while total atmospheric concentrations were 7.7-634 pg m(-3) across both lakes. A west-to-east gradient was observed for aqueous PCBs in Lake Erie. River discharge and localized influences (e.g., sediment resuspension and regional alongshore transport) likely dominated spatial trends of aqueous PCBs in both lakes. Air-water exchange fluxes of Σ7PCBs ranged from -2.4 (±1.9) ng m(-2) day(-1) (deposition) in Sheffield (site E03) to 9.0 (±3.1) ng m(-2) day(-1) (volatilization) in Niagara (site On05). Net volatilization of PCBs was the primary trend across most sites and periods. Almost half of variation in air-water exchange fluxes was attributed to the difference in aqueous concentrations of PCBs. Uncertainty analysis in fugacity ratios and mass fluxes in air-water exchange of PCBs indicated that PCBs have reached or approached equilibrium only at the eastern Lake Erie and along the Canadian shore of Lake Ontario sites, where air-water exchange fluxes dominated atmospheric concentrations.

  10. Prototype development and test results of a continuous ambient air monitoring system for hydrazine at the 10 ppb level

    NASA Technical Reports Server (NTRS)

    Meneghelli, Barry; Parrish, Clyde; Barile, Ron; Lueck, Dale E.

    1995-01-01

    A Hydrazine Vapor Area Monitor (HVAM) system is currently being field tested as a detector for the presence of hydrazine in ambient air. The MDA/Polymetron Hydrazine Analyzer has been incorporated within the HVAM system as the core detector. This analyzer is a three-electrode liquid analyzer typically used in boiler feed water applications. The HVAM system incorporates a dual-phase sample collection/transport method which simultaneously pulls ambient air samples containing hydrazine and a very dilute sulfuric acid solution (0.0001 M) down a length of 1/4 inch outside diameter (OD) tubing from a remote site to the analyzer. The hydrazine-laden dilute acid stream is separated from the air and the pH is adjusted by addition of a dilute caustic solution to a pH greater than 10.2 prior to analysis. Both the dilute acid and caustic used by the HVAM are continuously generated during system operation on an "as needed" basis by mixing a metered amount of concentrated acid/base with dilution water. All of the waste water generated by the analyzer is purified for reuse by Barnstead ion-exchange cartridges so that the entire system minimizes the generation of waste materials. The pumping of all liquid streams and mixing of the caustic solution and dilution water with the incoming sample are done by a single pump motor fitted with the appropriate mix of peristaltic pump heads. The signal to noise (S/N) ratio of the analyzer has been enhanced by adding a stirrer in the MDA liquid cell to provide mixing normally generated by the high liquid flow rate designed by the manufacturer. An onboard microprocessor continuously monitors liquid levels, sample vacuum, and liquid leak sensors, as well as handles communications and other system functions (such as shut down should system malfunctions or errors occur). The overall system response of the HVAM can be automatically checked at regular intervals by measuring the analyzer response to a metered amount of calibration standard injected

  11. Microbial communities in air and wine of a winery at two consecutive vintages.

    PubMed

    Pérez-Martín, Fátima; Seseña, Susana; Fernández-González, Mónica; Arévalo, María; Palop, María Llanos

    2014-11-03

    The aim of this study was to assess, both quantitatively and qualitatively, the populations of lactic acid bacteria (LAB) and yeasts in air and wine of a winery, in order to evaluate the possible exchange of microorganisms between them. Samples were taken in a winery located in Castilla-La Mancha (Spain) during the winemaking period of two consecutive vintages (2011 and 2012). The microbial composition was determined by using both a culture-dependent method and a culture-independent method, PCR-denaturing gradient gel electrophoresis (PCR-DGGE). In addition, genetic characterization of isolates from plates was carried out. A high diversity of species was detected in air and wine samples from both vintages. Leuconostoc mesenteroides was the predominant lactic acid bacteria in air from both vintages while Oenococcus oeni was the predominant in wine. Saccharomyces cerevisiae was the most frequently isolated yeast in both air and wine. Typing of O. oeni and S. cerevisiae isolates from air and wine samples showed the presence of coincident genotypes in both samples, that would confirm the exchange of microorganisms between the two environments, air and wine, and furthermore some of these genotypes were also found at samples taken at different vintages, indicating that they would remain in the winery. The results display the influence of the activity taking place in the winery and the moment of fermentation of the wines in tanks, on the microorganisms present in the air and the role of the air for the dispersal of microorganisms within the winery. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Assessment of the Revised 3410 Building Filtered Exhaust Stack Sampling Probe Location

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Xiao-Ying; Recknagle, Kurtis P.; Glissmeyer, John A.

    2013-12-01

    In order to support the air emissions permit for the 3410 Building, Pacific Northwest National Laboratory performed a series of tests in the exhaust air discharge from the reconfigured 3410 Building Filtered Exhaust Stack. The objective was to determine whether the location of the air sampling probe for emissions monitoring meets the applicable regulatory criteria governing such effluent monitoring systems. In particular, the capability of the air sampling probe location to meet the acceptance criteria of ANSI/HPS N13.1-2011 , Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stack and Ducts of Nuclear Facilities was determined. The qualification criteriamore » for these types of stacks address 1) uniformity of air velocity, 2) sufficiently small flow angle with respect to the axis of the duct, 3) uniformity of tracer gas concentration, and 4) uniformity of tracer particle concentration. Testing was performed to conform to the quality requirements of NQA-1-2000. Fan configurations tested included all fan combinations of any two fans at a time. Most of the tests were conducted at the normal flow rate, while a small subset of tests was performed at a slightly higher flow rate achieved with the laboratory hood sashes fully open. The qualification criteria for an air monitoring probe location are taken from ANSI/HPS N13.1-2011 and are paraphrased as follows with key results summarized: 1. Angular Flow—The average air velocity angle must not deviate from the axis of the stack or duct by more than 20°. Our test results show that the mean angular flow angles at the center two-thirds of the ducts are smaller than 4.5% for all testing conditions. 2. Uniform Air Velocity—The acceptance criterion is that the COV of the air velocity must be ≤ 20% across the center two thirds of the area of the stack. Our results show that the COVs of the air velocity across the center two-thirds of the stack are smaller than 2.9% for all testing conditions

  13. Chest tube management following pulmonary lobectomy: change of protocol results in fewer air leaks.

    PubMed

    Bertholet, Joost W M; Joosten, Joris J A; Keemers-Gels, Mariël E; van den Wildenberg, Frits J H; Barendregt, Wouter B

    2011-01-01

    Much controversy exists regarding the management of chest tubes following pulmonary lobectomy. The objective of this study was to analyse the effect of a new chest tube management protocol on clinical features, such as postoperative air leak, drain characteristics, 30-day postoperative complications and length of hospital stay. We retrospectively analysed 133 patients who underwent pulmonary lobectomy, from January 2005 to December 2008. A new chest tube protocol was introduced on 1 January 2007 and included placement of a single chest tube and early conversion to water seal. The chest tube was removed when air leak had resolved and (non-chylous) fluid drainage was <400 ml/day. The results of patients in the old (n=68) and the new protocol (n=65) were compared. In the new protocol group the median duration of air leak and duration of chest tube drainage declined significantly. Also the length of hospital stay decreased significantly to a median of eight days. The number of reinterventions and 30-day morbidity and mortality rates did not differ significantly. Our data suggest that placement of a single chest tube and early conversion to water seal decreases the duration of air leak and chest tube drainage and length of hospital stay.

  14. Air monitoring of volatile organic compounds at relevant receptors during hydraulic fracturing operations in Washington County, Pennsylvania.

    PubMed

    Maskrey, Joshua R; Insley, Allison L; Hynds, Erin S; Panko, Julie M

    2016-07-01

    A 3-month air monitoring study was conducted in Washington County, Pennsylvania, at the request of local community members regarding the potential risks resulting from air emissions of pollutants related to hydraulic fracturing operations. Continuous air monitoring for total volatile organic compounds was performed at two sampling sites, including a school and a residence, located within 900 m of a hydraulic fracturing well pad that had been drilled prior to the study. Intermittent 24-hour air samples for 62 individual volatile organic compounds were also collected. The ambient air at both sites was monitored during four distinct periods of unconventional natural gas extraction activity: an inactive period prior to fracturing operations, during fracturing operations, during flaring operations, and during another inactive period after operations. The results of the continuous monitoring during fracturing and flaring sampling periods for total volatile organic compounds were similar to the results obtained during inactive periods. Total volatile organic compound 24-hour average concentrations ranged between 0.16 and 80 ppb during all sampling periods. Several individual volatile compounds were detected in the 24-hour samples, but they were consistent with background atmospheric levels measured previously at nearby sampling sites and in other areas in Washington County. Furthermore, a basic yet conservative screening level evaluation demonstrated that the detected volatile organic compounds were well below health-protective levels. The primary finding of this study was that the operation of a hydraulic fracturing well pad in Washington County did not substantially affect local air concentrations of total and individual volatile organic compounds.

  15. Estimation of AUC or Partial AUC under Test-Result-Dependent Sampling.

    PubMed

    Wang, Xiaofei; Ma, Junling; George, Stephen; Zhou, Haibo

    2012-01-01

    The area under the ROC curve (AUC) and partial area under the ROC curve (pAUC) are summary measures used to assess the accuracy of a biomarker in discriminating true disease status. The standard sampling approach used in biomarker validation studies is often inefficient and costly, especially when ascertaining the true disease status is costly and invasive. To improve efficiency and reduce the cost of biomarker validation studies, we consider a test-result-dependent sampling (TDS) scheme, in which subject selection for determining the disease state is dependent on the result of a biomarker assay. We first estimate the test-result distribution using data arising from the TDS design. With the estimated empirical test-result distribution, we propose consistent nonparametric estimators for AUC and pAUC and establish the asymptotic properties of the proposed estimators. Simulation studies show that the proposed estimators have good finite sample properties and that the TDS design yields more efficient AUC and pAUC estimates than a simple random sampling (SRS) design. A data example based on an ongoing cancer clinical trial is provided to illustrate the TDS design and the proposed estimators. This work can find broad applications in design and analysis of biomarker validation studies.

  16. Direct impact aerosol sampling by electrostatic precipitation

    DOEpatents

    Braden, Jason D.; Harter, Andrew G.; Stinson, Brad J.; Sullivan, Nicholas M.

    2016-02-02

    The present disclosure provides apparatuses for collecting aerosol samples by ionizing an air sample at different degrees. An air flow is generated through a cavity in which at least one corona wire is disposed and electrically charged to form a corona therearound. At least one grounded sample collection plate is provided downstream of the at least one corona wire so that aerosol ions generated within the corona are deposited on the at least one grounded sample collection plate. A plurality of aerosol samples ionized to different degrees can be generated. The at least one corona wire may be perpendicular to the direction of the flow, or may be parallel to the direction of the flow. The apparatus can include a serial connection of a plurality of stages such that each stage is capable of generating at least one aerosol sample, and the air flow passes through the plurality of stages serially.

  17. Comparison of coarse coal dust sampling techniques in a laboratory-simulated longwall section.

    PubMed

    Patts, Justin R; Barone, Teresa L

    2017-05-01

    Airborne coal dust generated during mining can deposit and accumulate on mine surfaces, presenting a dust explosion hazard. When assessing dust hazard mitigation strategies for airborne dust reduction, sampling is done in high-velocity ventilation air, which is used to purge the mining face and gallery tunnel. In this environment, the sampler inlet velocity should be matched to the air stream velocity (isokinetic sampling) to prevent oversampling of coarse dust at low sampler-to-air velocity ratios. Low velocity ratios are often encountered when using low flow rate, personal sampling pumps commonly used in underground mines. In this study, with a goal of employing mine-ready equipment, a personal sampler was adapted for area sampling of coarse coal dust in high-velocity ventilation air. This was done by adapting an isokinetic nozzle to the inlet of an Institute of Occupational Medicine (Edinburgh, Scotland) sampling cassette (IOM). Collected dust masses were compared for the modified IOM isokinetic sampler (IOM-MOD), the IOM without the isokinetic nozzle, and a conventional dust sampling cassette without the cyclone on the inlet. All samplers were operated at a flow rate typical of personal sampling pumps: 2 L/min. To ensure differences between collected masses that could be attributed to sampler design and were not influenced by artifacts from dust concentration gradients, relatively uniform and repeatable dust concentrations were demonstrated in the sampling zone of the National Institute for Occupational Safety and Health experimental mine gallery. Consistent with isokinetic theory, greater differences between isokinetic and non-isokinetic sampled masses were found for larger dust volume-size distributions and higher ventilation air velocities. Since isokinetic sampling is conventionally used to determine total dust concentration, and isokinetic sampling made a difference in collected masses, the results suggest when sampling for coarse coal dust the IOM-MOD may

  18. Assessment of air sampling methods and size distribution of virus-laden aerosols in outbreaks in swine and poultry farms.

    PubMed

    Alonso, Carmen; Raynor, Peter C; Goyal, Sagar; Olson, Bernard A; Alba, Anna; Davies, Peter R; Torremorell, Montserrat

    2017-05-01

    Swine and poultry viruses, such as porcine reproductive and respiratory syndrome virus (PRRSV), porcine epidemic diarrhea virus (PEDV), and highly pathogenic avian influenza virus (HPAIV), are economically important pathogens that can spread via aerosols. The reliability of methods for quantifying particle-associated viruses as well as the size distribution of aerosolized particles bearing these viruses under field conditions are not well documented. We compared the performance of 2 size-differentiating air samplers in disease outbreaks that occurred in swine and poultry facilities. Both air samplers allowed quantification of particles by size, and measured concentrations of PRRSV, PEDV, and HPAIV stratified by particle size both within and outside swine and poultry facilities. All 3 viruses were detectable in association with aerosolized particles. Proportions of positive sampling events were 69% for PEDV, 61% for HPAIV, and 8% for PRRSV. The highest virus concentrations were found with PEDV, followed by HPAIV and PRRSV. Both air collectors performed equally for the detection of total virus concentration. For all 3 viruses, higher numbers of RNA copies were associated with larger particles; however, a bimodal distribution of particles was observed in the case of PEDV and HPAIV.

  19. [Distribution Characteristics of Heavy Metals in Environmental Samples Around Electroplating Factories and the Health Risk Assessment].

    PubMed

    Guo, Peng-ran; Lei, Yong-qian; Zhou, Qiao-li; Wang, Chang; Pan, Jia-chuan

    2015-09-01

    This study aimed to investigate the pollution degree and human health risk of heavy metals in soil and air samples around electroplating factories. Soil, air and waste gas samples were collected to measure 8 heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in two electroplating factories, located in Baiyun district of Guangzhou city. Geoaccumulation index and USEPA Risk Assessment Guidance for Superfund (RAGS) were respectively carried out. Results showed that concentrations of Hg and Pb in waste gas and Cr in air samples were higher than limits of the corresponding quality standards, and concentrations of Cd, Hg and Zn in soil samples reached the moderate pollution level. The HQ and HI of exposure by heavy metals in air and soil samples were both lower than 1, indicating that there was no non-carcinogen risk. CRAs and CRCr in soil samples were beyond the maximum acceptable level of carcinogen risk (10(-4)), and the contribution rate of CRCr to TCR was over 81%. CRCr, CRNi and TCR in air samples were in range of 10(-6) - 10(-4), indicating there was possibly carcinogen risk but was acceptable risk. CR values for children were higher than adults in soils, but were higher for adults in air samples. Correlation analysis revealed that concentrations of heavy metals in soils were significantly correlated with these in waste gas samples, and PCA data showed pollution sources of Cd, Hg and Zn in soils were different from other metals.

  20. Use of mass spectrometry coupled with a solids insertion probe to prescreen soil samples for environmental samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Check, C.E.; Bach, S.B.H.

    1995-12-31

    The contamination of air, water, and soils by a myriad of sources generates a large sample Currently, sample volume for hazardous constituent analyses is approximately half a million samples per year. The total analytical costs associated with this are astronomical. The analysis of these samples is vital in terms of assessing the types of contamination present and to what degree a site has been contaminated. The results of these analyses are very important for making an informed, knowledgeable decision as to the need for remediation and what type of remediation processes should be initiated based on site suitability vs non-actionmore » for the various sample sites. With an ever growing environmental consciousness in today`s society, the assessment and subsequent remediation of a site needs to be accomplished promptly despite the time constraints traditional methods place on such actions. In order to facilitate a rapid assessment, it is desirable to utilize instrumentation and equipment which afford the most information about a site allowing for optimization in environmental assessment while maintaining a realistic time schedule for the resulting remediation process. Because there are various types of environmental samples that can be taken at a site, different combinations of instrumentation and methods are required for assessing the level and type of contamination present whether it is in air, water, or soils. This study is limited to analyzing soil-like media that would normally fall under EPA Method 8270 which is used to analyze solid waste matrices, soils, and groundwater for semi-volatile organic compounds.« less

  1. Measurement of polyurethane foam - air partition coefficients for semivolatile organic compounds as a function of temperature: Application to passive air sampler monitoring.

    PubMed

    Francisco, Ana Paula; Harner, Tom; Eng, Anita

    2017-05-01

    Polyurethane foam - air partition coefficients (K PUF-air ) for 9 polycyclic aromatic hydrocarbons (PAHs), 10 alkyl-substituted PAHs, 4 organochlorine pesticides (OCPs) and dibenzothiophene were measured as a function of temperature over the range 5 °C-35 °C, using a generator column approach. Enthalpies of PUF-to-air transfer (ΔH PUF-air , kJ/mol) were determined from the slopes of log K PUF-air versus 1000/T (K), and have an average value of 81.2 ± 7.03 kJ/mol. The log K PUF-air values at 22 °C ranged from 4.99 to 7.25. A relationship for log K PUF-air versus log K OA was shown to agree with a previous relationship based on only polychlorinated biphenyls (PCBs) and derived from long-term indoor uptake study experiments. The results also confirm that the existing K OA -based model for predicting log K PUF-air values is accurate. This new information is important in the derivation of uptake profiles and effective air sampling volumes for PUF disk samplers so that results can be reported in units of concentration in air. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  2. 32 CFR 865.126 - Sample report format.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Sample report format. 865.126 Section 865.126 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ORGANIZATION AND MISSION-GENERAL PERSONNEL REVIEW BOARDS Air Force Discharge Review Board § 865.126 Sample report format. Summary...

  3. 32 CFR 865.126 - Sample report format.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Sample report format. 865.126 Section 865.126 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ORGANIZATION AND MISSION-GENERAL PERSONNEL REVIEW BOARDS Air Force Discharge Review Board § 865.126 Sample report format. Summary...

  4. RESULTS OF A PILOT FIELD STUDY TO EVALUATE THE EFFECTIVENESS OF CLEANING RESIDENTIAL HEATING AND AIR-CONDITIONING SYSTEMS AND THE IMPACT ON INDOOR AIR QUALITY AND SYSTEM PERFORMANCE

    EPA Science Inventory

    The report discusses and gives results of a pilot field study to evaluate the effectiveness of air duct cleaning (ADC) as a source removal technique in residential heating and air-conditioning (HAC) systems and its impact on airborne particle, fiber, and bioaerosol concentrations...

  5. Airtightness Results of Roof-Only Air Sealing Strategies on 1-1/2 Story Homes in Cold Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ojczyk, C.; Murry, T.; Mosiman, G.

    In this second study on solutions to ice dams in 1-1/2 story homes, five test homes located in both cold and very cold climates were analyzed for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. The reason for choosing this house type was they are very common in our area and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach for whole housemore » (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR Building America industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled us to compare air tightness data from over 220 homes using similar air seal methods.« less

  6. Description and evaluation of a peracetic acid air sampling and analysis method.

    PubMed

    Nordling, John; Kinsky, Owen R; Osorio, Magdalena; Pechacek, Nathan

    2017-12-01

    Peracetic acid (PAA) is a corrosive chemical with a pungent odor, which is extensively used in occupational settings and causes various health hazards in exposed workers. Currently, there is no US government agency recommended method that could be applied universally for the sampling and analysis of PAA. Legacy methods for determining airborne PAA vapor levels frequently suffered from cross-reactivity with other chemicals, particularly hydrogen peroxide (H 2 O 2 ). Therefore, to remove the confounding factor of cross-reactivity, a new viable, sensitive method was developed for assessment of PAA exposure levels, based on the differential reaction kinetics of PAA with methyl p-tolylsulfide (MTS), relative to H 2 O 2 , to preferentially derive methyl p-tolysulfoxide (MTSO). By quantifying MTSO concentration produced in the liquid capture solution from an air sampler, using an internal standard, and utilizing the reaction stoichiometry of PAA and MTS, the original airborne concentration of PAA is determined. After refining this liquid trap high-performance liquid chromatography (HPLC) method in the laboratory, it was tested in five workplace settings where PAA products were used. PAA levels ranged from the detection limit of 0.013 parts per million (ppm) to 0.4 ppm. The results indicate a viable and potentially dependable method to assess the concentrations of PAA vapors under occupational exposure scenarios, though only a small number of field measurements were taken while field testing this method. However, the low limit of detection and precision offered by this method makes it a strong candidate for further testing and validation to expand the uses of this liquid trap HPLC method.

  7. Monitoring of Microscopic Filamentous Fungi in Indoor Air of Transplant Unit.

    PubMed

    Holý, Ondřej; Matoušková, Ivanka; Kubátová, Alena; Hamal, Petr; Svobodová, Lucie; Jurásková, Eva; Raida, Luděk

    2015-12-01

    The aim of the study was to control the microbial contamination of indoor air monitored monthly at the Transplant Unit of the University Hospital Olomouc from August 2010 to July 2011. The unit is equipped with a three-stage air filtration system with HEPA filters. The MAS-100 air sampler (Merck, GER) was used. Twenty locations were singled out for the purposes of collecting a total of 720 samplings of the indoor air. Swabs of the HVAC diffusers at the sampling locations were always carried out after the sampling of the indoor air. In total, 480 samples of the indoor air were taken for Sabouraud chloramphenicol agar. In 11 cases (2.29%) the cultivation verified the presence of microscopic filamentous fungi. Only two cases involved the sanitary facilities of a patient isolation box; the other positive findings were from the facilities. The most frequent established genus was Aspergillus spp. (4x), followed by Trichoderma spp. (2x) and Penicillium spp. (2x), Paecilomyces spp., Eurotium spp., and Chrysonilia spp. (1x each). In 2 cases the cultivation established sterile aerial mycelium, unfortunately no further identification was possible. A total of 726 swabs of HVAC diffusers were collected (2 positive-0.28%). The study results demonstrated the efficacy of the HVAC equipment. With the continuing increase in the number of severely immunocompromised patients, hospitals are faced with the growing problem of invasive aspergillosis and other opportunistic infections. Preventive monitoring of microbial air contaminants is of major importance for the control of invasive aspergillosis. Copyright© by the National Institute of Public Health, Prague 2015.

  8. Oceanic Whitecaps and Associated, Bubble-Mediated, Air-Sea Exchange Processes

    DTIC Science & Technology

    1992-10-01

    experiments performed in laboratory conditions using Air-Sea Exchange Monitoring System (A-SEMS). EXPERIMENTAL SET-UP In a first look, the Air-Sea Exchange...Model 225, equipped with a Model 519 plug-in module. Other complementary information on A-SEMS along with results from first tests and calibration...between 9.50C and 22.40C within the first 24 hours after transferring the water sample into laboratory conditions. The results show an enhancement of

  9. ANNULAR IMPACTOR SAMPLING DEVICE

    DOEpatents

    Tait, G.W.C.

    1959-03-31

    A high-rate air sampler capable of sampling alphaemitting particles as small as 0.5 microns is described. The device is a cylindrical shaped cup that fits in front of a suction tube and which has sticky grease coating along its base. Suction forces contaminated air against the periodically monitored particle absorbing grease.

  10. The use of an air filtration system in podiatry clinics.

    PubMed

    McLarnon, Nichola; Burrow, Gordon; Maclaren, William; Aidoo, Kofi; Hepher, Mike

    2003-06-01

    A small-scale study was conducted to ascertain the efficiency and effectiveness of an air filtration system for use in podiatry/chiropody clinics (Electromedia Model 35F (A), Clean Air Ltd, Scotland, UK). Three clinics were identified, enabling comparison of data between podiatry clinics in the West of Scotland. The sampling was conducted using a portable Surface Air Sampler (Cherwell Laboratories, Bicester, UK). Samples were taken on two days at three different times before and after installation of the filtration units. The global results of the study indicate the filter has a statistically significant effect on microbial counts, with an average percentage decrease of 65%. This study is the first time, to the authors' knowledge, such a system has been tested within podiatric practice.

  11. The microbiological quality of air improves when using air conditioning systems in cars

    PubMed Central

    2010-01-01

    Background Because of better comfort, air conditioning systems are a common feature in automobiles these days. However, its impact on the number of particles and microorganisms inside the vehicle - and by this its impact on the risk of an allergic reaction - is yet unknown. Methods Over a time period of 30 months, the quality of air was investigated in three different types of cars (VW Passat, VW Polo FSI, Seat Alhambra) that were all equipped with a automatic air conditioning system. Operation modes using fresh air from outside the car as well as circulating air from inside the car were examined. The total number of microorganisms and the number of mold spores were measured by impaction in a high flow air sampler. Particles of 0.5 to 5.0 μm diameter were counted by a laser particle counter device. Results Overall 32 occasions of sampling were performed. The concentration of microorganisms outside the cars was always higher than it was inside the cars. Few minutes after starting the air conditioning system the total number of microorganisms was reduced by 81.7%, the number of mold spores was reduced by 83.3%, and the number of particles was reduced by 87.8%. There were no significant differences neither between the types of cars nor between the types of operation mode of the air conditioning system (fresh air vs. circulating air). All parameters that were looked for in this study improved during utilization of the car's air conditioning system. Conclusions We believe that the risk of an allergic reaction will be reduced during use also. Nevertheless, we recommend regular maintenance of the system and replacement of older filters after defined changing intervals. PMID:20515449

  12. Sample storage-induced changes in the quantity and quality of soil labile organic carbon

    PubMed Central

    Sun, Shou-Qin; Cai, Hui-Ying; Chang, Scott X.; Bhatti, Jagtar S.

    2015-01-01

    Effects of sample storage methods on the quantity and quality of labile soil organic carbon are not fully understood even though their effects on basic soil properties have been extensively studied. We studied the effects of air-drying and frozen storage on cold and hot water soluble organic carbon (WSOC). Cold- and hot-WSOC in air-dried and frozen-stored soils were linearly correlated with those in fresh soils, indicating that storage proportionally altered the extractability of soil organic carbon. Air-drying but not frozen storage increased the concentrations of cold-WSOC and carbohydrate in cold-WSOC, while both increased polyphenol concentrations. In contrast, only polyphenol concentration in hot-WSOC was increased by air-drying and frozen storage, suggesting that hot-WSOC was less affected by sample storage. The biodegradability of cold- but not hot-WSOC was increased by air-drying, while both air-drying and frozen storage increased humification index and changed specific UV absorbance of both cold- and hot-WSOC, indicating shifts in the quality of soil WSOC. Our results suggest that storage methods affect the quantity and quality of WSOC but not comparisons between samples, frozen storage is better than air-drying if samples have to be stored, and storage should be avoided whenever possible when studying the quantity and quality of both cold- and hot-WSOC. PMID:26617054

  13. Air permeability and trapped-air content in two soils

    USGS Publications Warehouse

    Stonestrom, David A.; Rubin, Jacob

    1989-01-01

    To improve understanding of hysteretic air permeability relations, a need exists for data on the water content dependence of air permeability, matric pressure, and air trapping (especially for wetting-drying cycles). To obtain these data, a special instrument was designed. The instrument is a combination of a gas permeameter (for air permeability determination), a suction plate apparatus (for retentivity curve determination), and an air pycnometer (for trapped-air-volume determination). This design allowed values of air permeability, matric pressure, and air trapping to be codetermined, i.e., determined at the same values of water content using the same sample and the same inflow-outflow boundaries. Such data were obtained for two nonswelling soils. The validity of the air permeability determinations was repeatedly confirmed by rigorous tests of Darcy's law. During initial drying from complete water saturation, supplementary measurements were made to assess the magnitude of gas slip. The extended Darcy equation accurately described the measured flux gradient relations for each condition of absolute gas pressure tested. Air permeability functions exhibited zero-permeability regions at high water contents as well as an abruptly appearing hysteresis at low water contents. Measurements in the zero-permeability regions revealed that the total amount of air in general exceeded the amount of trapped air. This indicates that the medium' s air space is partitioned into three measurable domains: through-flowing air, locally accessible air (i.e., air accessible from only one flow boundary), and trapped air. During repeated wetting and drying, the disappearance and reappearance of air permeability coincided closely with the reappearance and disappearance, respectively, of trapped air. The observed relation between critical features of the air permeability functions and those of the air-trapping functions suggest that water-based blockages play a significant role in the

  14. Research results: preserving newborn blood samples.

    PubMed

    Lewis, Michelle Huckaby; Scheurer, Michael E; Green, Robert C; McGuire, Amy L

    2012-11-07

    Retention and use, without explicit parental permission, of residual dried blood samples from newborn screening has generated public controversy over concerns about violations of family privacy rights and loss of parental autonomy. The public debate about this issue has included little discussion about the destruction of a potentially valuable public resource that can be used for research that may yield improvements in public health. The research community must advocate for policies and infrastructure that promote retention of residual dried blood samples and their use in biomedical research.

  15. Predictive Techniques for Spacecraft Cabin Air Quality Control

    NASA Technical Reports Server (NTRS)

    Perry, J. L.; Cromes, Scott D. (Technical Monitor)

    2001-01-01

    As assembly of the International Space Station (ISS) proceeds, predictive techniques are used to determine the best approach for handling a variety of cabin air quality challenges. These techniques use equipment offgassing data collected from each ISS module before flight to characterize the trace chemical contaminant load. Combined with crew metabolic loads, these data serve as input to a predictive model for assessing the capability of the onboard atmosphere revitalization systems to handle the overall trace contaminant load as station assembly progresses. The techniques for predicting in-flight air quality are summarized along with results from early ISS mission analyses. Results from groundbased analyses of in-flight air quality samples are compared to the predictions to demonstrate the technique's relative conservatism.

  16. Automated simultaneous measurement of the δ(13) C and δ(2) H values of methane and the δ(13) C and δ(18) O values of carbon dioxide in flask air samples using a new multi cryo-trap/gas chromatography/isotope ratio mass spectrometry system.

    PubMed

    Brand, Willi A; Rothe, Michael; Sperlich, Peter; Strube, Martin; Wendeberg, Magnus

    2016-07-15

    The isotopic composition of greenhouse gases helps to constrain global budgets and to study sink and source processes. We present a new system for high-precision stable isotope measurements of carbon, hydrogen and oxygen in atmospheric methane and carbon dioxide. The design is intended for analyzing flask air samples from existing sampling programs without the need for extra sample air for methane analysis. CO2 and CH4 isotopes are measured simultaneously using two isotope ratio mass spectrometers, one for the analysis of δ(13) C and δ(18) O values and the second one for δ(2) H values. The inlet carousel delivers air from 16 sample positions (glass flasks 1-5 L and high-pressure cylinders). Three 10-port valves take aliquots from the sample stream. CH4 from 100-mL air aliquots is preconcentrated in 0.8-mL sample loops using a new cryo-trap system. A precisely calibrated working reference air is used in parallel with the sample according to the Principle of Identical Treatment. It takes about 36 hours for a fully calibrated analysis of a complete carousel including extractions of four working reference and one quality control reference air. Long-term precision values, as obtained from the quality control reference gas since 2012, account for 0.04 ‰ (δ(13) C values of CO2 ), 0.07 ‰ (δ(18) O values of CO2 ), 0.11 ‰ (δ(13) C values of CH4 ) and 1.0 ‰ (δ(2) H values of CH4 ). Within a single day, the system exhibits a typical methane δ(13) C standard deviation (1σ) of 0.06 ‰ for 10 repeated measurements. The system has been in routine operation at the MPI-BGC since 2012. Consistency of the data and compatibility with results from other laboratories at a high precision level are of utmost importance. A high sample throughput and reliability of operation are important achievements of the presented system to cope with the large number of air samples to be analyzed. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Interlaboratory evaluation of a standardized inductively coupled plasma mass spectrometry method for the determination of trace beryllium in air filter samples.

    PubMed

    Ashley, Kevin; Brisson, Michael J; Howe, Alan M; Bartley, David L

    2009-12-01

    A collaborative interlaboratory evaluation of a newly standardized inductively coupled plasma mass spectrometry (ICP-MS) method for determining trace beryllium in workplace air samples was carried out toward fulfillment of method validation requirements for ASTM International voluntary consensus standard test methods. The interlaboratory study (ILS) was performed in accordance with an applicable ASTM International standard practice, ASTM E691, which describes statistical procedures for investigating interlaboratory precision. Uncertainty was also estimated in accordance with ASTM D7440, which applies the International Organization for Standardization Guide to the Expression of Uncertainty in Measurement to air quality measurements. Performance evaluation materials (PEMs) used consisted of 37 mm diameter mixed cellulose ester filters that were spiked with beryllium at levels of 0.025 (low loading), 0.5 (medium loading), and 10 (high loading) microg Be/filter; these spiked filters were prepared by a contract laboratory. Participating laboratories were recruited from a pool of over 50 invitees; ultimately, 20 laboratories from Europe, North America, and Asia submitted ILS results. Triplicates of each PEM (blanks plus the three different loading levels) were conveyed to each volunteer laboratory, along with a copy of the draft standard test method that each participant was asked to follow; spiking levels were unknown to the participants. The laboratories were requested to prepare the PEMs by one of three sample preparation procedures (hotplate or microwave digestion or hotblock extraction) that were described in the draft standard. Participants were then asked to analyze aliquots of the prepared samples by ICP-MS and to report their data in units of mu g Be/filter sample. Interlaboratory precision estimates from participating laboratories, computed in accordance with ASTM E691, were 0.165, 0.108, and 0.151 (relative standard deviation) for the PEMs spiked at 0.025, 0

  18. Comparison of passive diffusion bag samplers and submersible pump sampling methods for monitoring volatile organic compounds in ground water at Area 6, Naval Air Station, Whidbey Island, Washington

    USGS Publications Warehouse

    Huffman, Raegan L.

    2002-01-01

    Ground-water samples were collected in April 1999 at Naval Air Station Whidbey Island, Washington, with passive diffusion samplers and a submersible pump to compare concentrations of volatile organic compounds (VOCs) in water samples collected using the two sampling methods. Single diffusion samplers were installed in wells with 10-foot screened intervals, and multiple diffusion samplers were installed in wells with 20- to 40-foot screened intervals. The diffusion samplers were recovered after 20 days and the wells were then sampled using a submersible pump. VOC concentrations in the 10-foot screened wells in water samples collected with diffusion samplers closely matched concentrations in samples collected with the submersible pump. Analysis of VOC concentrations in samples collected from the 20- to 40-foot screened wells with multiple diffusion samplers indicated vertical concentration variation within the screened interval, whereas the analysis of VOC concentrations in samples collected with the submersible pump indicated mixing during pumping. The results obtained using the two sampling methods indicate that the samples collected with the diffusion samplers were comparable with and can be considerably less expensive than samples collected using a submersible pump.

  19. Measurements of Atmospheric Methane and 13C/12C of Atmospheric Methane from Flask Air Samples (1999)

    DOE Data Explorer

    Quay, Paul [School of Oceanography, University of Washington; Stutsman, Johnny [School of Oceanography, University of Washington

    1999-01-01

    This database offers precise measurements of atmospheric methane and 13C/12C in atmospheric methane from flask air samples collected at eight sites worldwide and aboard NOAA cruises in the Pacific Ocean. The eight sites include Olympic Peninsula, Washington; Cape Grim, Tasmania; Fraserdale, Ontario; Marshall Islands; Baring Head, New Zealand; Mauna Loa, Hawaii; Point Barrow, Alaska; and American Samoa. The measurements span the period 1988 to mid-1996. These data are useful for global methane budget analyses and for determining the atmospheric isotopic composition of methane. All isotopic measurements have been corrected for standard drift.

  20. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  1. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  2. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  3. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.245... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  4. Influence of air on polybutadiene used in the preparation of stationary phases for high-performance liquid chromatography.

    PubMed

    Lopes, Nilva P; Collins, Kenneth E; Jardim, Isabel C S F

    2004-03-19

    A 100 ml bottle of polybutadiene, PBD, was repeatedly exposed to air over a period of 6 months. Samples were taken at time zero (PBD-0), after 3 months (PBD-3) and 6 months (PBD-6). These samples were sorbed onto HPLC silica by an open-air solution-evaporation procedure, which involved exposure to the atmosphere for 6 days. Portions of the three sets of samples were used to compare self-immobilization and the effects of 100 degrees C thermal treatments in air or nitrogen on HPLC performance of the resulting phases. It is concluded that self-immobilization is enhanced by prior exposure of sorbed PBD to air and subsequent heating at 100 degrees C further enhances column performance. The best performance (10(5) plates m(-1)) resulted from 4 h heating of PBD-6 material in nitrogen.

  5. [Effectiveness of the maintenance operations on the air conditioning systems of a university building in relation to the microbiological quality of the air indoor].

    PubMed

    De Filippis, Patrizia; Spinaci, Anna; Coia, Maura; Maggi, Oriana; Panà, Augusto

    2003-01-01

    The microbiological quality of the air indoor is influenced from various factors and one of the most important is represented from the maintenance of the conditioning systems. In this study it has been estimated the effectiveness of an intervention of cleaning and maintenance on the systems of conditioning of an university building executing sampling before and after such intervention. The two results were confronted and it is observed as the maintenance of the air conditioners has influenced on the quality of the air indoor.

  6. Journal Article: the National Dioxin Air Monitoring Network ...

    EPA Pesticide Factsheets

    In June, 1998, the U.S. EPA established the National Dioxin Air Monitoring Network (NDAMN). The primary goal of NDAMN is determine the temporal and geographical variability of atmospheric CDDs, CDFs, and coplanar PCBs at rural and nonimpacted locations throughout the United States. Currently operating at 32 sampling stations, NDAMN has three primary purposes: (1) to determine the atmospheric levels and occurrences of dioxin-like compounds in rural and agricultural areas where livestock, poultry and animal feed crops are grown; (2) to provide measurements of atmospheric levels of dioxin-like compounds in different geographic regions of the U.S.; and (3) to provide information regarding the long-range transport of dioxin-like compounds in air over the U.S. At Dioxin 2000, we reported on the preliminary results of monitoring at 9 rural locations from June 1998 through June 1999. By the end of 1999, NDAMN had expanded to 21 sampling stations. Then, at Dioxin 2001, we reported the results of the first 18 months of operation of NDAMN at 15 rural and 6 National Park stations in the United States. The following is intended to be an update to this national monitoring effort. We are reporting the air monitoring results of 17 rural and 8 National Park NDAMN stations operational over 4 sampling moments during calendar year 2000. Two stations located in suburban Washington DC and San Francisco, CA are more urban in character and serve as an indicator of CDD/F and cop

  7. Simple and accurate quantification of BTEX in ambient air by SPME and GC-MS.

    PubMed

    Baimatova, Nassiba; Kenessov, Bulat; Koziel, Jacek A; Carlsen, Lars; Bektassov, Marat; Demyanenko, Olga P

    2016-07-01

    Benzene, toluene, ethylbenzene and xylenes (BTEX) comprise one of the most ubiquitous and hazardous groups of ambient air pollutants of concern. Application of standard analytical methods for quantification of BTEX is limited by the complexity of sampling and sample preparation equipment, and budget requirements. Methods based on SPME represent simpler alternative, but still require complex calibration procedures. The objective of this research was to develop a simpler, low-budget, and accurate method for quantification of BTEX in ambient air based on SPME and GC-MS. Standard 20-mL headspace vials were used for field air sampling and calibration. To avoid challenges with obtaining and working with 'zero' air, slope factors of external standard calibration were determined using standard addition and inherently polluted lab air. For polydimethylsiloxane (PDMS) fiber, differences between the slope factors of calibration plots obtained using lab and outdoor air were below 14%. PDMS fiber provided higher precision during calibration while the use of Carboxen/PDMS fiber resulted in lower detection limits for benzene and toluene. To provide sufficient accuracy, the use of 20mL vials requires triplicate sampling and analysis. The method was successfully applied for analysis of 108 ambient air samples from Almaty, Kazakhstan. Average concentrations of benzene, toluene, ethylbenzene and o-xylene were 53, 57, 11 and 14µgm(-3), respectively. The developed method can be modified for further quantification of a wider range of volatile organic compounds in air. In addition, the new method is amenable to automation. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Preliminary Results on the Use of Leather Chrome Shavings for Air Passive Sampling

    PubMed Central

    Sanjuán-Herráez, D.; Chabaane, L.; Tahiri, S.; Pastor, A.; de la Guardia, M.

    2012-01-01

    A new passive sampler based on low-density polyethylene (LDPE) layflat tube filled with chrome shavings from tannery waste residues was evaluated to determine volatile organic compounds (VOCs) in indoor and outdoor areas. VOCs were directly determined by head space-gas chromatography-mass spectrometry (HS-GC-MS) without any pretreatment of the sampler and avoiding the use of solvents. Limit of detection values ranging from 20 to 75 ng sampler−1 and good repeatability values were obtained for VOCs under study with relative standard deviation values from 2.8 to 9.6% except for carbon disulfide for which it was 22.5%. The effect of the amount of chrome shavings per sampler was studied and results were compared with those obtained using empty LDPE tubes, to demonstrate the capacity of chrome shavings to adsorb VOCs. PMID:22900233

  9. Validation of the Asthma Illness Representation Scale-Spanish (AIRS-S).

    PubMed

    Sidora-Arcoleo, Kimberly Joan; Feldman, Jonathan; Serebrisky, Denise; Spray, Amanda

    2010-05-01

    To expand knowledge surrounding parental illness representations (IRs) of their children's asthma, it is imperative that culturally appropriate survey instruments are developed and validated for use in clinical and research settings. The Asthma Illness Representation Scale (AIRS) provides a structured assessment of the key components of asthma IRs, allowing the health care provider (HCP) to quickly identify areas of discordance with the professional model of asthma management. The English AIRS was developed and validated among a geographically and ethnically diverse sample. The authors present the validation results of the AIRS-S (Spanish) from a sample of Mexican and Puerto Rican parents. The AIRS was translated and back translated per approved methodologies. Factor analysis, internal reliability, external validity, and 2-week test-retest reliability (on a subsample) were carried out and results compared with the validated English version. Data were obtained from 80 Spanish-speaking Mexican and Puerto Rican parents of children with asthma. The sample was recruited from two school-based health centers and a free medical clinic in Phoenix, Arizona, and a hospital-based asthma clinic in Bronx, New York. The original Nature of Asthma Symptoms, Facts About Asthma, and Attitudes Towards Medication Use subscales emerged. Remaining factors were a mixture of items with no coherent or theoretical distinction between them. Interpretation of results is limited due to not meeting the minimum requirement of 5 observations/item. Cronbach's alpha coefficients for the total score (alpha = .77) and majority of subscales (alpha range = .53-.77) were acceptable and consistent with the English version. Parental reports of a positive relationship with the HCP significantly predicted AIRS scores congruent with the professional model; longer asthma duration was associated with beliefs aligned with the lay model; and AIRS scores congruent with the professional model were related to lower

  10. BiOCl micro-assembles consisting of ultrafine nanoplates: A high performance electro-catalyst for air electrode of Al-air batteries

    NASA Astrophysics Data System (ADS)

    Yuan, Jinlan; Wang, Jin; She, Yiyi; Hu, Jing; Tao, Pengpeng; Lv, Fucong; Lu, Zhouguang; Gu, Yingying

    2014-10-01

    BiOCl micro-assembles appearing spherical and plate-like in shape consisting of ultrafine nanoplates were successfully synthesized by a simple hydrothermal method. The obtained BiOCl micro-assembles were characterized as oxygen reduction reaction (ORR) catalyst for air electrode of aluminum air batteries by using linear polarization and constant-current discharge techniques. The effect of precursor concentration on the electrochemical properties of the air electrodes based on the synthesized BiOCl micro-assembles was intensively investigated. The results demonstrated that the BiOCl catalyst exhibited promising ORR performance. Koutecky-Levich analysis indicated that a two-electron reaction was favored for the ORR mechanism of the BiOCl (0.18) sample.

  11. 3-D Surface Depression Profiling Using High Frequency Focused Air-Coupled Ultrasonic Pulses

    NASA Technical Reports Server (NTRS)

    Roth, Don J.; Kautz, Harold E.; Abel, Phillip B.; Whalen, Mike F.; Hendricks, J. Lynne; Bodis, James R.

    1999-01-01

    Surface topography is an important variable in the performance of many industrial components and is normally measured with diamond-tip profilometry over a small area or using optical scattering methods for larger area measurement. This article shows quantitative surface topography profiles as obtained using only high-frequency focused air-coupled ultrasonic pulses. The profiles were obtained using a profiling system developed by NASA Glenn Research Center and Sonix, Inc (via a formal cooperative agreement). (The air transducers are available as off-the-shelf items from several companies.) The method is simple and reproducible because it relies mainly on knowledge and constancy of the sound velocity through the air. The air transducer is scanned across the surface and sends pulses to the sample surface where they are reflected back from the surface along the same path as the incident wave. Time-of-flight images of the sample surface are acquired and converted to depth/surface profile images using the simple relation (d = V*t/2) between distance (d), time-of-flight (t), and the velocity of sound in air (V). The system has the ability to resolve surface depression variations as small as 25 microns, is useable over a 1.4 mm vertical depth range, and can profile large areas only limited by the scan limits of the particular ultrasonic system. (Best-case depth resolution is 0.25 microns which may be achievable with improved isolation from vibration and air currents.) The method using an optimized configuration is reasonably rapid and has all quantitative analysis facilities on-line including 2-D and 3-D visualization capability, extreme value filtering (for faulty data), and leveling capability. Air-coupled surface profilometry is applicable to plate-like and curved samples. In this article, results are shown for several proof-of-concept samples, plastic samples burned in microgravity on the STS-54 space shuttle mission, and a partially-coated cylindrical ceramic

  12. Soil separator and sampler and method of sampling

    DOEpatents

    O'Brien, Barry H [Idaho Falls, ID; Ritter, Paul D [Idaho Falls, ID

    2010-02-16

    A soil sampler includes a fluidized bed for receiving a soil sample. The fluidized bed may be in communication with a vacuum for drawing air through the fluidized bed and suspending particulate matter of the soil sample in the air. In a method of sampling, the air may be drawn across a filter, separating the particulate matter. Optionally, a baffle or a cyclone may be included within the fluidized bed for disentrainment, or dedusting, so only the finest particulate matter, including asbestos, will be trapped on the filter. The filter may be removable, and may be tested to determine the content of asbestos and other hazardous particulate matter in the soil sample.

  13. Hydrodebridement of wounds: effectiveness in reducing wound bacterial contamination and potential for air bacterial contamination.

    PubMed

    Bowling, Frank L; Stickings, Daryl S; Edwards-Jones, Valerie; Armstrong, David G; Boulton, Andrew Jm

    2009-05-08

    The purpose of this study was to assess the level of air contamination with bacteria after surgical hydrodebridement and to determine the effectiveness of hydro surgery on bacterial reduction of a simulated infected wound. Four porcine samples were scored then infected with a broth culture containing a variety of organisms and incubated at 37 degrees C for 24 hours. The infected samples were then debrided with the hydro surgery tool (Versajet, Smith and Nephew, Largo, Florida, USA). Samples were taken for microbiology, histology and scanning electron microscopy pre-infection, post infection and post debridement. Air bacterial contamination was evaluated before, during and after debridement by using active and passive methods; for active sampling the SAS-Super 90 air sampler was used, for passive sampling settle plates were located at set distances around the clinic room. There was no statistically significant reduction in bacterial contamination of the porcine samples post hydrodebridement. Analysis of the passive sampling showed a significant (p < 0.001) increase in microbial counts post hydrodebridement. Levels ranging from 950 colony forming units per meter cubed (CFUs/m3) to 16780 CFUs/m3 were observed with active sampling of the air whilst using hydro surgery equipment compared with a basal count of 582 CFUs/m3. During removal of the wound dressing, a significant increase was observed relative to basal counts (p < 0.05). Microbial load of the air samples was still significantly raised 1 hour post-therapy. The results suggest a significant increase in bacterial air contamination both by active sampling and passive sampling. We believe that action might be taken to mitigate fallout in the settings in which this technique is used.

  14. Evaluation of air quality in a megacity using statistics tools

    NASA Astrophysics Data System (ADS)

    Ventura, Luciana Maria Baptista; de Oliveira Pinto, Fellipe; Soares, Laiza Molezon; Luna, Aderval Severino; Gioda, Adriana

    2018-06-01

    Local physical characteristics (e.g., meteorology and topography) associate to particle concentrations are important to evaluate air quality in a region. Meteorology and topography affect air pollutant dispersions. This study used statistics tools (PCA, HCA, Kruskal-Wallis, Mann-Whitney's test and others) to a better understanding of the relationship between fine particulate matter (PM2.5) levels and seasons, meteorological conditions and air basins. To our knowledge, it is one of the few studies performed in Latin America involving all parameters together. PM2.5 samples were collected in six sampling sites with different emission sources (industrial, vehicular, soil dust) in Rio de Janeiro, Brazil. The PM2.5 daily concentrations ranged from 1 to 61 µg m-3, with averages higher than the annual limit (15 µg m-3) for some of the sites. The results of the statistics evaluation showed that PM2.5 concentrations were not influenced by seasonality. Furthermore, air basins defined previously were not confirmed, because some sites presented similar emission sources. Therefore, new redefinitions of air basins need to be done, once they are important to air quality management.

  15. Evaluation of air quality in a megacity using statistics tools

    NASA Astrophysics Data System (ADS)

    Ventura, Luciana Maria Baptista; de Oliveira Pinto, Fellipe; Soares, Laiza Molezon; Luna, Aderval Severino; Gioda, Adriana

    2017-03-01

    Local physical characteristics (e.g., meteorology and topography) associate to particle concentrations are important to evaluate air quality in a region. Meteorology and topography affect air pollutant dispersions. This study used statistics tools (PCA, HCA, Kruskal-Wallis, Mann-Whitney's test and others) to a better understanding of the relationship between fine particulate matter (PM2.5) levels and seasons, meteorological conditions and air basins. To our knowledge, it is one of the few studies performed in Latin America involving all parameters together. PM2.5 samples were collected in six sampling sites with different emission sources (industrial, vehicular, soil dust) in Rio de Janeiro, Brazil. The PM2.5 daily concentrations ranged from 1 to 61 µg m-3, with averages higher than the annual limit (15 µg m-3) for some of the sites. The results of the statistics evaluation showed that PM2.5 concentrations were not influenced by seasonality. Furthermore, air basins defined previously were not confirmed, because some sites presented similar emission sources. Therefore, new redefinitions of air basins need to be done, once they are important to air quality management.

  16. Pulling Results Out of Thin Air: Four Years of Ozone and Greenhouse Gas Measurements by the Alpha Jet Atmospheric Experiment (AJAX)

    NASA Technical Reports Server (NTRS)

    Yates, Emma

    2015-01-01

    The Alpha Jet Atmospheric eXperiment (AJAX) has been measuring atmospheric ozone, carbon dioxide, methane and meteorological parameters from near the surface to 8000 m since January 2011. The main goals are to study photochemical ozone production and the impacts of extreme events on western US air quality, provide data to support satellite observations and aid in the quantification of emission sources e.g. wildfires, urban outflow, diary and oil and gas. The aircraft is based at Moffett Field and flies multiple times a month to sample vertical profiles at selected sites in California and Nevada, providing long-term data records at these sites. AJAX is also uniquely positioned to launch with short notice sampling flights in rapid response to extreme events e.g. the 2013 Yosemite Rim fire. This talk will focus on the impacts of vertical transport on surface air quality, and investigation of emission sources from diaries and wildfires.

  17. Total airborne mold particle sampling: evaluation of sample collection, preparation and counting procedures, and collection devices.

    PubMed

    Godish, Diana; Godish, Thad

    2008-02-01

    This study was conducted to evaluate (i) procedures used to collect, prepare, and count total airborne mold spore/particle concentrations, and (ii) the relative field performance of three commercially available total airborne mold spore/particle sampling devices. Differences between factory and laboratory airflow calibration values of axial fan-driven sampling instruments (used in the study) indicated a need for laboratory calibration using a mass flow meter to ensure that sample results were accurately calculated. An aniline blue-amended Calberla's solution adjusted to a pH of 4.2-4.4 provided good sample mounting/counting results using Dow Corning high vacuum grease, Dow Corning 280A adhesive, and Dow Corning 316 silicone release spray for samples collected using mini-Burkard and Allergenco samplers. Count variability among analysts was most pronounced in 5% counts of relatively low mold particle deposition density samples and trended downward with increased count percentage and particle deposition density. No significant differences were observed among means of 5, 10, and 20% counts and among analysts; a significant interaction effect was observed between analysts' counts and particle deposition densities. Significantly higher mini-Burkard and Air-O-Cell total mold spore/particle counts for 600x vs. 400x (1.9 and 2.3 x higher, respectively), 1000x vs. 600x (1.9 and 2.2 x higher, respectively) and 1000x vs. 400x (3.6 and 4.6 x higher, respectively) comparisons indicated that 1000x magnification counts best quantified total airborne mold spore/particles using light microscopy, and that lower magnification counts may result in unacceptable underreporting of airborne mold spore/particle concentrations. Modest but significantly higher (1.2x) total mold spore concentrations were observed with Allergenco vs. mini-Burkard samples collected in co-located, concurrently operated sampler studies; moderate but significantly higher mini-Burkard count values (1.4x) were

  18. Sampling Key Populations for HIV Surveillance: Results From Eight Cross-Sectional Studies Using Respondent-Driven Sampling and Venue-Based Snowball Sampling

    PubMed Central

    Stahlman, Shauna; Hargreaves, James; Weir, Sharon; Edwards, Jessie; Rice, Brian; Kochelani, Duncan; Mavimbela, Mpumelelo; Baral, Stefan

    2017-01-01

    Background In using regularly collected or existing surveillance data to characterize engagement in human immunodeficiency virus (HIV) services among marginalized populations, differences in sampling methods may produce different pictures of the target population and may therefore result in different priorities for response. Objective The objective of this study was to use existing data to evaluate the sample distribution of eight studies of female sex workers (FSW) and men who have sex with men (MSM), who were recruited using different sampling approaches in two locations within Sub-Saharan Africa: Manzini, Swaziland and Yaoundé, Cameroon. Methods MSM and FSW participants were recruited using either respondent-driven sampling (RDS) or venue-based snowball sampling. Recruitment took place between 2011 and 2016. Participants at each study site were administered a face-to-face survey to assess sociodemographics, along with the prevalence of self-reported HIV status, frequency of HIV testing, stigma, and other HIV-related characteristics. Crude and RDS-adjusted prevalence estimates were calculated. Crude prevalence estimates from the venue-based snowball samples were compared with the overlap of the RDS-adjusted prevalence estimates, between both FSW and MSM in Cameroon and Swaziland. Results RDS samples tended to be younger (MSM aged 18-21 years in Swaziland: 47.6% [139/310] in RDS vs 24.3% [42/173] in Snowball, in Cameroon: 47.9% [99/306] in RDS vs 20.1% [52/259] in Snowball; FSW aged 18-21 years in Swaziland 42.5% [82/325] in RDS vs 8.0% [20/249] in Snowball; in Cameroon 15.6% [75/576] in RDS vs 8.1% [25/306] in Snowball). They were less educated (MSM: primary school completed or less in Swaziland 42.6% [109/310] in RDS vs 4.0% [7/173] in Snowball, in Cameroon 46.2% [138/306] in RDS vs 14.3% [37/259] in Snowball; FSW: primary school completed or less in Swaziland 86.6% [281/325] in RDS vs 23.9% [59/247] in Snowball, in Cameroon 87.4% [520/576] in RDS vs 77.5% [238

  19. Improved Atmospheric Sampling of Hexavalent Chromium

    PubMed Central

    Torkmahalleh, Mehdi Amouei; Yu, Chang-Ho; Lin, Lin; Fan, Zhihua (Tina); Swift, Julie L.; Bonanno, Linda; Rasmussen, Don H.; Holsen, Thomas M.; Hopke, Philip K.

    2015-01-01

    Hexavalent chromium (Cr(VI)) and trivalent chromium (Cr(III)) are the primary chromium oxidation states found in ambient atmospheric particulate matter. While Cr(III) is relatively nontoxic, Cr(VI) is toxic and exposure to Cr(VI) may lead to cancer, nasal damage, asthma, bronchitis, and pneumonitis. Accurate measurement of the ambient Cr(VI) concentrations is an environmental challenge since Cr(VI) can be reduced to Cr(III) and vice versa during sampling. In the present study, a new Cr(VI) sampler (Clarkson sampler) was designed, constructed, and field tested to improve the sampling of Cr(VI) in ambient air. The new Clarkson Cr(VI) sampler was based on the concept that deliquescence during sampling leads to aqueous phase reactions. Thus, the relative humidity of the sampled air was reduced below the deliquescence relative humidity (DRH) of the ambient particles. The new sampler was operated to collect Total Suspended Particles (TSP), and compared side-by-side with the current National Air Toxics Trends Stations (NATTS) Cr(VI) sampler that is utilized in the United States Environmental Protection Agency (USEPA) air toxics monitoring program. Side-by-side field testing of the samplers occurred in Elizabeth, NJ during the winter and summer of 2012. The average recovery values of Cr(VI) spikes after 24 hour sampling intervals during summer and winter sampling were 57 and 72%, respectively, for the Clarkson sampler, while the corresponding average values for NATTS samplers were 46% for both summer and winter sampling, respectively. Preventing the ambient aerosol collected on the filters from deliquescing is a key to improving the sampling of Cr(VI). PMID:24344574

  20. Fabrication of a printed capacitive air-gap touch sensor

    NASA Astrophysics Data System (ADS)

    Lee, Sang Hoon; Seo, Hwiwon; Lee, Sangyoon

    2018-05-01

    Unlike lithography-based processes, printed electronics does not require etching, which makes it difficult to fabricate electronic devices with an air gap. In this study, we propose a method to fabricate capacitive air-gap touch sensors via printing and coating. First, the bottom electrode was fabricated on a flexible poly(ethylene terephthalate) (PET) substrate using roll-to-roll gravure printing with silver ink. Then poly(dimethylsiloxane) (PDMS) was spin coated to form a sacrificial layer. The top electrode was fabricated on the sacrificial layer by spin coating with a stretchable silver ink. The sensor samples were then put in a tetrabutylammonium (TBAF) bath to generate the air gap by removing the sacrificial layer. The capacitance of the samples was measured for verification, and the results show that the capacitance increases in proportion to the applied force from 0 to 2.5 N.