Orthogonal design on range hood with air curtain and its effects on kitchen environment.
Liu, Xiaomin; Wang, Xing; Xi, Guang
2014-01-01
Conventional range hoods cannot effectively prevent the oil fumes containing cooking-induced harmful material from escaping into the kitchen Air curtains and guide plates have been used in range hoods to reduce the escape of airborne emissions and heat, thereby improving the kitchen environment and the cook's degree of comfort. In this article, numerical simulations are used to study the effects of the jet velocity of an air curtain, the jet angle of the air curtain, the width of the jet slot, the area of the guide plate, and the exhaust rate of the range hood on the perceived temperature, the perceived concentration of oil fumes, the release temperature of oil fumes, and the concentration of escaped oil fumes in a kitchen. The orthogonal experiment results show that the exhaust rate of the range hood is the main factor influencing the fumes concentration and the temperature distribution in the kitchen. For the range hood examined in the present study, the optimum values of the exhaust rate, the jet velocity of the air curtain, the jet angle of the air curtain, the width of the jet slot, and the area of the guide plate are 10.5 m(3)/min, 1.5 m/s, -5°, 4 mm, and 0.22 m(2), respectively, based on the results of the parametric study. In addition, the velocity field, temperature field, and oil fumes concentration field in the kitchen using the proposed range hood with the air curtain and guide plate are analyzed for those parameters. The study's results provide significant information needed for improving the kitchen environment.
Chen, Jia-Kun
2016-08-01
An inclined plate for flow control was installed at the lower edge of the sash of an inclined air-curtain fume hood to reduce the effects of the wake around a worker standing in front of the fume hood. Flow inside the fume hood is controlled by the inclined air-curtain and deflection plates, thereby forming a quad-vortex flow structure. Controlling the face velocity of the fume hood resulted in convex, straight, concave, and attachment flow profiles in the inclined air-curtain. We used the flow visualization and conducted a tracer gas test with a mannequin to determine the performance of two sash geometries, namely, the half-cylinder and inclined plate designs. When the half-cylinder design was used, the tracer gas test registered a high leakage concentration at Vf ≦ 57.1 fpm or less. This concentration occurred at the top of the sash opening, which was close to the breathing zone of the mannequin placed in front of the fume hood. When the inclined plate design was used, the containment was good, with concentrations of 0.002-0.004 ppm, at Vf ≦ 63.0 fpm. Results indicate that an inclined plate effectively reduces the leakage concentration induced by recirculation flow structures that form in the wake of a worker standing in front of an inclined air-curtain fume hood.
Flow characteristics of an inclined air-curtain range hood in a draft
CHEN, Jia-Kun
2015-01-01
The inclined air-curtain technology was applied to build an inclined air-curtain range hood. A draft generator was applied to affect the inclined air-curtain range hood in three directions: lateral (θ=0°), oblique (θ=45°), and front (θ=90°). The three suction flow rates provided by the inclined air-curtain range hood were 10.1, 10.9, and 12.6 m3/min. The laser-assisted flow visualization technique and the tracer-gas test method were used to investigate the performance of the range hood under the influence of a draft. The results show that the inclined air-curtain range hood has a strong ability to resist the negative effect of a front draft until the draft velocity is greater than 0.5 m/s. The oblique draft affected the containment ability of the inclined air-curtain range hood when the draft velocity was larger than 0.3 m/s. When the lateral draft effect was applied, the capture efficiency of the inclined air-curtain range hood decreased quickly in the draft velocity from 0.2 m/s to 0.3 m/s. However, the capture efficiencies of the inclined air-curtain range hood under the influence of the front draft were higher than those under the influence of the oblique draft from 0.3 m/s to 0.5 m/s. PMID:25810445
Flow characteristics of an inclined air-curtain range hood in a draft.
Chen, Jia-Kun
2015-01-01
The inclined air-curtain technology was applied to build an inclined air-curtain range hood. A draft generator was applied to affect the inclined air-curtain range hood in three directions: lateral (θ=0°), oblique (θ=45°), and front (θ=90°). The three suction flow rates provided by the inclined air-curtain range hood were 10.1, 10.9, and 12.6 m(3)/min. The laser-assisted flow visualization technique and the tracer-gas test method were used to investigate the performance of the range hood under the influence of a draft. The results show that the inclined air-curtain range hood has a strong ability to resist the negative effect of a front draft until the draft velocity is greater than 0.5 m/s. The oblique draft affected the containment ability of the inclined air-curtain range hood when the draft velocity was larger than 0.3 m/s. When the lateral draft effect was applied, the capture efficiency of the inclined air-curtain range hood decreased quickly in the draft velocity from 0.2 m/s to 0.3 m/s. However, the capture efficiencies of the inclined air-curtain range hood under the influence of the front draft were higher than those under the influence of the oblique draft from 0.3 m/s to 0.5 m/s.
Bell, Geoffrey C.; Feustel, Helmut E.; Dickerhoff, Darryl J.
2002-01-01
A fume hood is provided having an adequate level of safety while reducing the amount of air exhausted from the hood. A displacement flow fume hood works on the principal of a displacement flow which displaces the volume currently present in the hood using a push-pull system. The displacement flow includes a plurality of air supplies which provide fresh air, preferably having laminar flow, to the fume hood. The displacement flow fume hood also includes an air exhaust which pulls air from the work chamber in a minimally turbulent manner. As the displacement flow produces a substantially consistent and minimally turbulent flow in the hood, inconsistent flow patterns associated with contaminant escape from the hood are minimized. The displacement flow fume hood largely reduces the need to exhaust large amounts of air from the hood. It has been shown that exhaust air flow reductions of up to 70% are possible without a decrease in the hood's containment performance. The fume hood also includes a number of structural adaptations which facilitate consistent and minimally turbulent flow within a fume hood.
Energy efficient laboratory fume hood
Feustel, Helmut E.
2000-01-01
The present invention provides a low energy consumption fume hood that provides an adequate level of safety while reducing the amount of air exhausted from the hood. A low-flow fume hood in accordance with the present invention works on the principal of providing an air supply, preferably with low turbulence intensity, in the face of the hood. The air flow supplied displaces the volume currently present in the hood's face without significant mixing between the two volumes and with minimum injection of air from either side of the flow. This air flow provides a protective layer of clean air between the contaminated low-flow fume hood work chamber and the laboratory room. Because this protective layer of air will be free of contaminants, even temporary mixing between the air in the face of the fume hood and room air, which may result from short term pressure fluctuations or turbulence in the laboratory, will keep contaminants contained within the hood. Protection of the face of the hood by an air flow with low turbulence intensity in accordance with a preferred embodiment of the present invention largely reduces the need to exhaust large amounts of air from the hood. It has been shown that exhaust air flow reductions of up to 75% are possible without a decrease in the hood's containment performance.
ERIC Educational Resources Information Center
Saunders, G. Thomas
1985-01-01
Provides information on updating older fume hoods. Areas addressed include: (1) adjustment of the hood's back baffle; (2) hood air leakage; (3) light level; (4) hood location in relation to room traffic and room air; and (5) establishing and maintaining hood performance. (JN)
NASA Astrophysics Data System (ADS)
Fonseca, Ana S.; Kuijpers, Eelco; Kling, Kirsten I.; Levin, Marcus; Koivisto, Antti J.; Nielsen, Signe H.; Fransman, W.; Fedutik, Yijri; Jensen, Keld A.; Koponen, Ismo K.
2018-02-01
Fume hoods are one of the most common types of equipment applied to reduce the potential of particle exposure in laboratory environments. A number of previous studies have shown particle release during work with nanomaterials under fume hoods. Here, we assessed laboratory workers' inhalation exposure during synthesis and handling of CuO, TiO2 and ZnO in a fume hood. In addition, we tested the capacity of a fume hood to prevent particle release to laboratory air during simulated spillage of different powders (silica fume, zirconia TZ-3Y and TiO2). Airborne particle concentrations were measured in near field, far field, and in the breathing zone of the worker. Handling CuO nanoparticles increased the concentration of small particles (< 58 nm) inside the fume hood (up to 1 × 105 cm-3). Synthesis, handling and packaging of ZnO and TiO2 nanoparticles did not result in detectable particle release to the laboratory air. Simulated powder spills showed a systematic increase in the particle concentrations inside the fume hood with increasing amount of material and drop height. Despite powder spills were sometimes observed to eject into the laboratory room, the spill events were rarely associated with notable release of particles from the fume hood. Overall, this study shows that a fume hood generally offers sufficient exposure control during synthesis and handling of nanomaterials. An appropriate fume hood with adequate sash height and face velocity prevents 98.3% of particles release into the surrounding environment. Care should still be made to consider spills and high cleanliness to prevent exposure via resuspension and inadvertent exposure by secondary routes.
Dunn, Kevin H.; Tsai, Candace Su-Jung; Woskie, Susan R.; Bennett, James S.; Garcia, Alberto; Ellenbecker, Michael J.
2015-01-01
The most commonly reported control used to minimize workplace exposures to nanomaterials is the chemical fume hood. Studies have shown, however, that significant releases of nanoparticles can occur when materials are handled inside fume hoods. This study evaluated the performance of a new commercially available nano fume hood using three different test protocols. Tracer gas, tracer nanoparticle, and nanopowder handling protocols were used to evaluate the hood. A static test procedure using tracer gas (sulfur hexafluoride) and nanoparticles as well as an active test using an operator handling nanoalumina were conducted. A commercially available particle generator was used to produce sodium chloride tracer nanoparticles. Containment effectiveness was evaluated by sampling both in the breathing zone (BZ) of a mannequin and operator as well as across the hood opening. These containment tests were conducted across a range of hood face velocities (60, 80, and 100 feet/minute) and with the room ventilation system turned off and on. For the tracer gas and tracer nanoparticle tests, leakage was much more prominent on the left side of the hood (closest to the room supply air diffuser) although some leakage was noted on the right side and in the BZ sample locations. During the tracer gas and tracer nanoparticle tests, leakage was primarily noted when the room air conditioner was on for both the low and medium hood exhaust air flows. When the room air conditioner was turned off, the static tracer gas tests showed good containment across most test conditions. The tracer gas and nanoparticle test results were well correlated showing hood leakage under the same conditions and at the same sample locations. The impact of a room air conditioner was demonstrated with containment being adversely impacted during the use of room air ventilation. The tracer nanoparticle approach is a simple method requiring minimal setup and instrumentation. However, the method requires the reduction in background concentrations to allow for increased sensitivity. PMID:25175285
The Use of Feedback in Lab Energy Conservation: Fume Hoods at MIT
ERIC Educational Resources Information Center
Wesolowski, Daniel; Olivetti, Elsa; Graham, Amanda; Lanou, Steve; Cooper, Peter; Doughty, Jim; Wilk, Rich; Glicksman, Leon
2010-01-01
Purpose: The purpose of this paper is to report on the results of an Massachusetts Institute of Technology Chemistry Department campaign to reduce energy consumption in chemical fume hoods. Hood use feedback to lab users is a crucial component of this campaign. Design/methodology/approach: Sash position sensor data on variable air volume fume…
Dunn, Kevin H; Tsai, Candace Su-Jung; Woskie, Susan R; Bennett, James S; Garcia, Alberto; Ellenbecker, Michael J
2014-01-01
The most commonly reported control used to minimize workplace exposures to nanomaterials is the chemical fume hood. Studies have shown, however, that significant releases of nanoparticles can occur when materials are handled inside fume hoods. This study evaluated the performance of a new commercially available nano fume hood using three different test protocols. Tracer gas, tracer nanoparticle, and nanopowder handling protocols were used to evaluate the hood. A static test procedure using tracer gas (sulfur hexafluoride) and nanoparticles as well as an active test using an operator handling nanoalumina were conducted. A commercially available particle generator was used to produce sodium chloride tracer nanoparticles. Containment effectiveness was evaluated by sampling both in the breathing zone (BZ) of a mannequin and operator as well as across the hood opening. These containment tests were conducted across a range of hood face velocities (60, 80, and 100 ft/min) and with the room ventilation system turned off and on. For the tracer gas and tracer nanoparticle tests, leakage was much more prominent on the left side of the hood (closest to the room supply air diffuser) although some leakage was noted on the right side and in the BZ sample locations. During the tracer gas and tracer nanoparticle tests, leakage was primarily noted when the room air conditioner was on for both the low and medium hood exhaust airflows. When the room air conditioner was turned off, the static tracer gas tests showed good containment across most test conditions. The tracer gas and nanoparticle test results were well correlated showing hood leakage under the same conditions and at the same sample locations. The impact of a room air conditioner was demonstrated with containment being adversely impacted during the use of room air ventilation. The tracer nanoparticle approach is a simple method requiring minimal setup and instrumentation. However, the method requires the reduction in background concentrations to allow for increased sensitivity.
Reduction of cooking oil fume exposure following an engineering intervention in Chinese restaurants.
Pan, Chih-Hong; Shih, Tung-Sheng; Chen, Chiou-Jong; Hsu, Jin-Huei; Wang, Shun-Chih; Huang, Chien-Ping; Kuo, Ching-Tang; Wu, Kuen-Yuh; Hu, Howard; Chan, Chang-Chuan
2011-01-01
A new engineering intervention measure, an embracing air curtain device (EACD), was used to increase the capture efficiency of cooker hoods and reduce cooking oil fume (COF) exposure in Chinese restaurants. An EACD was installed in six Chinese restaurants where the cooks complained of COF exposure. Before- and after-installation measurements were taken to compare changes in particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) in kitchen air, and changes in levels of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA). The association between PM and PAHs in air and 8-OHdG and MDA in urine was evaluated by linear mixed-effects regression analysis. Results showed that geometric mean kitchen air levels of PM(10), PM(2.5), PM(1.0) and total particulate PAHs were significantly reduced after the EACDs were introduced. Urinary levels of 8-OHdG and MDA in cooks were also significantly lower after EACD instalment. PM(2.5), PM(1.0) and benzo(a)pyrene (BaP) levels were positively associated with urinary 8-OHdG levels after adjusting for key personal covariates. Urinary MDA levels in cooks were also positively associated with BaP levels after adjusting for key personal covariates. This study demonstrates that the EACD is effective for reducing COF and oxidative stress levels in cooks working in Chinese kitchens.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-12
... and hood fume interface with Phoenix Controls hood. The components were specifically designed to fit... Module Assembly to repair existing Johnson Controls Lab and Hood Fume Interface with Phoenix Controls... Johnson Controls lab and hood fume interface with Phoenix Controls hood (where utilization of an American...
40 CFR 61.172 - Standard for new and existing sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... converter mouth, charging ladles, skimming ladles, and any other material transfer vessels used will be... and secondary hood system at all times as follows: (i) Copper converter. (A) Increase the air curtain... horizontal slot. (2) The velocity of air through the horizontal slot during each mode of converter operation...
40 CFR 61.172 - Standard for new and existing sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... converter mouth, charging ladles, skimming ladles, and any other material transfer vessels used will be... and secondary hood system at all times as follows: (i) Copper converter. (A) Increase the air curtain... horizontal slot. (2) The velocity of air through the horizontal slot during each mode of converter operation...
40 CFR 61.172 - Standard for new and existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... converter mouth, charging ladles, skimming ladles, and any other material transfer vessels used will be... and secondary hood system at all times as follows: (i) Copper converter. (A) Increase the air curtain... horizontal slot. (2) The velocity of air through the horizontal slot during each mode of converter operation...
40 CFR 61.172 - Standard for new and existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... converter mouth, charging ladles, skimming ladles, and any other material transfer vessels used will be... and secondary hood system at all times as follows: (i) Copper converter. (A) Increase the air curtain... horizontal slot. (2) The velocity of air through the horizontal slot during each mode of converter operation...
Energy Systems Fabrication Laboratory | Energy Systems Integration Facility
Fabrication The fuel cell fabrication hub includes laboratory spaces with local exhaust and chemical fume hoods that support electrolysis and other chemical process research. Key Infrastructure Perchloric acid washdown hood, local exhaust, specialty gas manifolding, deionized water, chemical fume hoods, glassware
Laboratory Ventilation and Safety.
ERIC Educational Resources Information Center
Steere, Norman V.
1965-01-01
In order to meet the needs of both safety and economy, laboratory ventilation systems must effectively remove air-borne toxic and flammable materials and at the same time exhaust a minimum volume of air. Laboratory hoods are the most commonly used means of removing gases, dusts, mists, vapors, and fumed from laboratory operations. To be effective,…
Vortex ventilation in the laboratory environment.
Meisenzahl, Lawrence R
2014-01-01
Assured containment at low airflow has long eluded the users of ventilated enclosures including chemical fume hoods used throughout industry. It is proposed that containment will be enhanced in a hood that has a particular interior shape that causes a natural vortex to occur. The sustained vortex improves the containment of contaminants within the enclosure at low airflow. This hypothesis was tested using the ASHRAE 110 tracer gas test. A known volume of tracer gas was emitted in the hood. A MIRAN SapphIRe infrared spectrometer was used to measure the concentration of tracer gas that escapes the enclosure. The design of the experiment included a written operating procedure, data collection plan, and statistical analysis of the data. A chemical fume hood of traditional design was tested. The hood interior was then reconstructed to enhance the development of a vortex inside the enclosure. The hood was retested using the same method to compare the performance of the traditional interior shape with the enhanced vortex shape. In every aspect, the vortex hood showed significant improvement over the traditional hood design. Use of the Hood Index characterizing the dilution of gas in an air stream as a logarithmic function indicates a causal relationship between containment and volumetric airflow through an enclosure. Use of the vortex effect for ventilated enclosures can provide better protection for the user and lower operating cost for the owner. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a data collection spreadsheet, data analysis, and data collection procedure.].
10. LOOKING SOUTH IN BOP SHOP AT FUME HOOD AND ...
10. LOOKING SOUTH IN BOP SHOP AT FUME HOOD AND SPARE OXYGEN LANCES ON THE SERVICE FLOOR OF THE FURNACE AISLE. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA
A comparative study for radiological decontamination of laboratory fume hood materials.
Thomas, Elizabeth; Sweet, Lucas; MacFarlan, Paul; McNamara, Bruce; Kerschner, Harrison
2012-08-01
The efficacy for radiological decontamination of the laboratory standard fume hood as constructed of stainless steel, compared to that of powder-coated carbon steel is described. While the chemical inertness of powder-coated surfaces is good, faced with everyday abrasion, aggressive inorganic solutions and vapors, and penetrating organics commonly employed in government laboratory fume hoods, radiological decontamination of powder-coated steel surfaces was found to be similar to those made of stainless steel for easily solubilized or digestible radionuclides. Plutonium was difficult to remove from stainless steel and powder-coated surfaces, especially after prolonged contact times.
2013-08-30
turntable inside the hood to maintain a constant weld speed, while the ER308L stainless steel wire were fed by the welding gun. Figure 2. Fume chamber...size distribution, density and specific surface area of welding fumes from SMAW and GMAW mild- steel and stainless - steel consumables, American...shipyards. It uses mild or stainless steel filler material to join pieces of metal. The intense energy expended in the welding process results in the
Code of Federal Regulations, 2012 CFR
2012-07-01
... exhaust ventilation when used as described in (a) shall be designed to prevent dispersion into the air of... shall be so designed that dusts, fumes, mists, vapors, or gases are not drawn through the work area of employees. (c) Design and operation. Exhaust fans, jets, ducts, hoods, separators, and all necessary...
The Benefits of Mixed Flow Technology: Roof Exhaust Fans.
ERIC Educational Resources Information Center
Tetley, Paul A.
2001-01-01
Explores the problems associated with laboratory workstation exhaust faced by most colleges and universities and explains how the selection of a proper fume hood exhaust system can prevent or eliminate these problems and provide a clean and safe lab environment. Also highlighted are indoor air quality legal implications. (GR)
Persistence of Change: Fume Hood Campaign Lessons
ERIC Educational Resources Information Center
Feder, Elah; Robinson, Jennifer; Wakefield, Sarah
2012-01-01
Purpose: Sustainability initiatives typically operate for a limited time period, but it is often unclear whether they have lasting effects. The purpose of this paper is to examine a laboratory fume hood campaign, in order to identify factors that might contribute or detract from long-term change persistence. Design/methodology/approach: The…
Flow Characteristics and Robustness of an Inclined Quad-vortex Range Hood
CHEN, Jia-Kun; HUANG, Rong Fung
2014-01-01
A novel design of range hood, which was termed the inclined quad-vortex (IQV) range hood, was examined for its flow and containment leakage characteristics under the influence of a plate sweeping across the hood face. A flow visualization technique was used to unveil the flow behavior. Three characteristic flow modes were observed: convex, straight, and concave modes. A tracer gas detection method using sulfur hexafluoride (SF6) was employed to measure the containment leakage levels. The results were compared with the test data reported previously in the literature for a conventional range hood and an inclined air curtain (IAC) range hood. The leakage SF6 concentration of the IQV range hood under the influence of the plate sweeping was 0.039 ppm at a suction flow rate of 9.4 m3/min. The leakage concentration of the conventional range hood was 0.768 ppm at a suction flow rate of 15.0 m3/min. For the IAC range hood, the leakage concentration was 0.326 ppm at a suction flow rate of 10.9 m3/min. The IQV range hood presented a significantly lower leakage level at a smaller suction flow rate than the conventional and IAC range hoods due to its aerodynamic design for flow behavior. PMID:24583513
Hydrogen Supply System for Small PEM Fuel Cell Stacks
1997-07-01
a trivalent metal capable of forming complex hydrides such as Al or B. m is the valence of Z and n is the valence of X For example, let X be chlorine...been taken, the reactor is opened into a fume hood. After the reactor reaches atmospheric pressure, it is re-pressurized with nitrogen and bled again...into the fume hood to remove the remaining vapors before it is opened. After the fumes have dissipated, the endcap is loosened and removed. The spent
Effects of Growth Conditions on the Measured Electrical Properties of Monolayer Molybdenum Disulfide
2017-02-01
rpm (thickness around 300 nm) and then baked on a hotplate at 185 °C for 2 min. The PMMA was exposed using a proximity effect correction with a base...and then soft baked at 50 °C in air for 30 min. After air-drying in a fume hood for an additional 3 h at room temperature, the PMMA was scraped from
Effects of boundary-layer separation controllers on a desktop fume hood.
Huang, Rong Fung; Chen, Jia-Kun; Hsu, Ching Min; Hung, Shuo-Fu
2016-10-02
A desktop fume hood installed with an innovative design of flow boundary-layer separation controllers on the leading edges of the side plates, work surface, and corners was developed and characterized for its flow and containment leakage characteristics. The geometric features of the developed desktop fume hood included a rearward offset suction slot, two side plates, two side-plate boundary-layer separation controllers on the leading edges of the side plates, a slanted surface on the leading edge of the work surface, and two small triangular plates on the upper left and right corners of the hood face. The flow characteristics were examined using the laser-assisted smoke flow visualization technique. The containment leakages were measured by the tracer gas (sulphur hexafluoride) detection method on the hood face plane with a mannequin installed in front of the hood. The results of flow visualization showed that the smoke dispersions induced by the boundary-layer separations on the leading edges of the side plates and work surface, as well as the three-dimensional complex flows on the upper-left and -right corners of the hood face, were effectively alleviated by the boundary-layer separation controllers. The results of the tracer gas detection method with a mannequin standing in front of the hood showed that the leakage levels were negligibly small (≤0.003 ppm) at low face velocities (≥0.19 m/s).
Personal exposure to metal fume, NO2, and O3 among production welders and non-welders.
Schoonover, Todd; Conroy, Lorraine; Lacey, Steven; Plavka, Julie
2011-01-01
The objective of this study was to characterize personal exposures to welding-related metals and gases for production welders and non-welders in a large manufacturing facility. Welding fume metals and irritant gases nitrogen dioxide (NO(2)) and ozone (O(3)) were sampled for thirty-eight workers. Personal exposure air samples for welding fume metals were collected on 37 mm open face cassettes and nitrogen dioxide and ozone exposure samples were collected with diffusive passive samplers. Samples were analyzed for metals using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and welding fume metal exposure concentrations were defined as the sum of welding-related metals mass per volume of air sampled. Welding fume metal exposures were highly variable among similar types of welding while NO(2) and O(3) exposure were less variable. Welding fume metal exposures were significantly higher 474 μg/m(3) for welders than non-welders 60 μg/m(3) (p=0.001). Welders were exposed to higher concentrations of NO(2) and O(3) than non-welders but the differences were not statistically significant. Welding fume metal exposure concentrations for welders performing gas metal arc welding (GMAW) and shielded metal arc welding (SMAW) were higher than welders performing gas tungsten arc welding (GTAW). Non-welders experienced exposures similar to GTAW welders despite a curtain wall barrier separating welding and non-welding work areas.
2013-03-01
materials have been introduced as dopants: Vanadium (V), Chromium (Cr), Manganese (Mn), Lead (Pb), and Iron (Fe) [41, 42, 43, 44]. While these...value reported in literature, 188°C, due to the samples being heated on an open air hot plate in a laminar flow fume hood. The average resistivity of
Corrosion-Mitigating, Bondable, Fluorinated Barrier Coating for Anodized Magnesium
2016-05-01
transport the precursor vapor throughout the study was set at 9,500 sccm. The setup also incorporated a 38- × 54- × 0.6-cm stainless steel moveable...evaporated and that silane crosslinking had occurred, samples were allowed to sit uncovered in a fume hood for 1 h prior to electrochemical...measurement, contact-angle measurement, or plasma treatment. Samples were stored in a fume hood for approximately 24 h before applying an epoxy topcoat
Post-Decontamination Vapor Sampling and Analytical Test Methods
2015-08-12
construction materials (e.g., acrylic, stainless steel , glass, etc.) for containing the chemical contaminants, coupons, coupon holders, and decontaminant(s...made of inert materials, e.g., stainless steel , T6061 aluminum, or equivalent. The construction material may be treated to further minimize...include glove ports. The chamber may have certified fume hoods for the containment of toxic chemicals. All exhaust air must be filtered to
Flynn, Michael R; Susi, Pam
2012-08-01
Arc welding is a common unit operation in the construction industry, where frequent changes in location and welding position make it more difficult to control fume exposures than in industries where fixed locations are the norm. Welders may be exposed to a variety of toxic airborne contaminants including manganese (Mn) and hexavalent chromium (CrVI). Local exhaust ventilation (LEV) is a well-known engineering control for welding fumes but has not been adopted widely in the construction industry. This literature review presents data on the performance of a variety of LEV systems for welding fume control from the construction (five references), shipyard (five references), and other industries. The studies indicate that LEV can reduce fume exposures to total particulate, Mn, and CrVI to levels below currently relevant standards. Field studies suggest that 40-50% or more reduction in exposure is possible with portable or fixed LEV systems relative to natural ventilation but that correct positioning of the hood and adequate exhaust flow rates are essential. Successful implementation of extraction guns for gas metal arc welding (GMAW) and flux core arc welding has been demonstrated, indicating that a successful balance between extraction airflow and shielding gas requirements is possible. Work practices are an important part of achieving successful control of fume exposures; in particular, positioning the hood close to the arc, checking exhaust flow rates, and avoiding the plume. Further research is needed on hood size effects for controlling welding fume with portable LEV systems and identifying and overcoming barriers to LEV use in construction.
Protective smoke hood studies.
DOT National Transportation Integrated Search
1970-12-01
The report describes the evaluation and testing of a high-temperature resistant, transparent, polyimide hood designed to protect aircraft passengers and crew from the effects of toxic fumes, smoke and flame resulting from an aircraft accident. As a '...
Environmental Consequences of Nanotechnologies: Nanoparticle Dispersion in Aqueous Media: SOP-T-1
2015-02-01
containing ice • Bath sonicator • Weighing dish (aluminum) • Stainless steel spatula • Analytical balance • Lab jack for lifting sample • Volumetric...balance and an aluminum dish, weigh an adequate mass of dry powder under a fume hood to achieve the desired concentration into ultrapure water (<T>, <R...0.025 0.5 0.05 1 0.5 10 1 20 2. Add ultra-pure water in a glass beaker with NP powder to /flask under fume hood (<T>, <R>). 3. Degas the bath
4. INTERIOR VIEW OF CHEMISTRY LAB LOOKING SOUTHEAST; NOTE FUME ...
4. INTERIOR VIEW OF CHEMISTRY LAB LOOKING SOUTHEAST; NOTE FUME EXHAUST HOOD AT LEFT & ORIGINAL CEILING FIXTURE - Fort McCoy, Building No. T-1033, North side of South Tenth Avenue, Block 10, Sparta, Monroe County, WI
Life Sciences Laboratory 2 Fan Exhaust Mixing Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Flaherty, Julia E.; Antonio, Ernest J.
An SF 6 tracer release was performed in the LSL-II ventilation stack over the weekend of March 5, 2016. The primary purpose of this study was to experimentally determine the gaseous concentration of material from a fume hood to the fan outlet, as well as at typical worker locations, to gain an understanding of potential worker exposures impacts. Five different fan operating configurations were utilized to ensure that the full spectrum of historical operating configurations was addressed. Some summary points from this study include: •Relatively high concentrations were observed within the stack area. –Between 50 and 100% of the exhaustmore » concentration may be observed within the stack. •Background concentrations were observed outside the stack area. –Workers outside the stack itself, but on the roof, are unlikely to be impacted by the exhaust. •Elevated concentrations on the order of 25% of the exhaust concentrations were observed within the Penthouse. •Transport time from a laboratory fume hood to the exhaust fan is within one to two minutes. •Penthouse concentrations climb from background levels to steady state over 15+ minutes. •Wind speed and wind direction did not play a significant role in the test outcomes. –A slight bias in the concentration distribution may be discernable based on wind speed and direction. •When both fans are operating, material from fume hoods on the east side preferentially flow through the east fan, while material from fume hoods on the west side preferentially flow through the west fan. This effectively doubles the concentration at that fan. This mixing study will inform other study components to develop a more complete picture of the worker potential exposure from LSL-II Rooftop activities. Estimating the mean concentration in the stack from chemical inventories and fume hood emissions for both current and historical laboratory activities is a separate effort. These estimates of mean ventilation concentrations will utilize this mixing study to estimate the potential exposure to workers working in and around the LSL-II stack.« less
Viano, David C; Parenteau, Chantal S
2016-07-03
Insurance Institute for Highway Safety (IIHS) high-hooded side impacts were analyzed for matched vehicle tests with and without side airbags. The comparison provides a measure of the effectiveness of side airbags in reducing biomechanical responses for near-side occupants struck by trucks, SUVs, and vans at 50 km/h. The IIHS moving deformable barrier (MDB) uses a high-hooded barrier face. It weighs 1,500 kg and impacts the driver side perpendicular to the vehicle at 50 km/h. SID IIs dummies are placed in the driver and left second-row seats. They represent fifth percentile female occupants. IIHS tests were reviewed for matches with one test with a side airbag and another without it in 2003-2007 model year (MY) vehicles. Four side airbag systems were evaluated: (1) curtain and torso side airbags, (2) head and torso side airbag, (3) curtain side airbag, and (4) torso side airbag. There were 24 matched IIHS vehicle tests: 13 with and without a curtain and torso side airbags, 4 with and without a head and torso side airbag, 5 with and without a side curtain airbag, and 2 with and without a torso airbag. The head, chest, and pelvis responses were compared for each match and the average difference was determined across all matches for a type of side airbag. The average reduction in head injury criterion (HIC) was 68 ± 16% (P < .001) with curtain and torso side airbags compared to the HIC without side airbags. The average HIC was 296 with curtain and torso side airbags and 1,199 without them. The viscous response (VC) was reduced 54 ± 19% (P < .005) with curtain and torso side airbags. The combined acetabulum and ilium force (7 ± 15%) and pelvic acceleration (-2 ± 17%) were essentially similar in the matched tests. The head and torso side airbag reduced HIC by 42 ± 30% (P < .1) and VC by 32 ± 26% compared to vehicles without a side airbag. The average HIC was 397 with the side head and torso airbag compared to 729 without it. The curtain airbag and torso airbag only showed lower head responses but essentially no difference in the chest and pelvis responses. The curtain and torso side airbags effectively reduced biomechanical responses for the head and chest in 50 km/h side impacts with a high-hooded deformable barrier. The reductions in the IIHS tests are directionally the same as estimated fatality reductions in field crashes reported by NHTSA for side airbags.
Management Observation Facility Fume Hoods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sundsmo, V. A.
I reviewed all the hoods used for AS&I work in buildings 253, 254, and 255. All have had the minimum annual surveys conducted and some have had semi-annual reviews. The operating parameter labels are posted consistent to the right or above right (with the only exception the perchloric acid hood in 1734- on the left) which facilitates users knowing where to check for information. All hoods with sash doors (except the SE one in 1734 have a note on the Operating Parameters label to "keep sash doors closed". Again, this was checking consistency. No surveys were missed.
Topham, Nathan; Wang, Jun; Kalivoda, Mark; Huang, Joyce; Yu, Kuei-Min; Hsu, Yu-Mei; Wu, Chang-Yu; Oh, Sewon; Cho, Kuk; Paulson, Kathleen
2012-03-01
Hexavalent chromium (Cr(6+)) emitted from welding poses serious health risks to workers exposed to welding fumes. In this study, tetramethylsilane (TMS) was added to shielding gas to control hazardous air pollutants produced during stainless steel welding. The silica precursor acted as an oxidation inhibitor when it decomposed in the high-temperature welding arc, limiting Cr(6+) formation. Additionally, a film of amorphous SiO(2) was deposited on fume particles to insulate them from oxidation. Experiments were conducted following the American Welding Society (AWS) method for fume generation and sampling in an AWS fume hood. The results showed that total shielding gas flow rate impacted the effectiveness of the TMS process. Increasing shielding gas flow rate led to increased reductions in Cr(6+) concentration when TMS was used. When 4.2% of a 30-lpm shielding gas flow was used as TMS carrier gas, Cr(6+) concentration in gas metal arc welding (GMAW) fumes was reduced to below the 2006 Occupational Safety and Health Administration standard (5 μg m(-3)) and the efficiency was >90%. The process also increased fume particle size from a mode size of 20 nm under baseline conditions to 180-300 nm when TMS was added in all shielding gas flow rates tested. SiO(2) particles formed in the process scavenged nanosized fume particles through intercoagulation. Transmission electron microscopy imagery provided visual evidence of an amorphous film of SiO(2) on some fume particles along with the presence of amorphous SiO(2) agglomerates. These results demonstrate the ability of vapor phase silica precursors to increase welding fume particle size and minimize chromium oxidation, thereby preventing the formation of hexavalent chromium.
Code of Federal Regulations, 2014 CFR
2014-07-01
... reflective surfaces. (iv) Inert-gas metal-arc welding on stainless steel shall not be performed unless..., fumes and smoke below a hazardous level. (ii) Local exhaust ventilation shall consist of movable hoods... not exposed to hazardous levels of fumes: (A) Lead base metals; (B) Cadmium-bearing filler materials...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reflective surfaces. (iv) Inert-gas metal-arc welding on stainless steel shall not be performed unless..., fumes and smoke below a hazardous level. (ii) Local exhaust ventilation shall consist of movable hoods... not exposed to hazardous levels of fumes: (A) Lead base metals; (B) Cadmium-bearing filler materials...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reflective surfaces. (iv) Inert-gas metal-arc welding on stainless steel shall not be performed unless..., fumes and smoke below a hazardous level. (ii) Local exhaust ventilation shall consist of movable hoods... not exposed to hazardous levels of fumes: (A) Lead base metals; (B) Cadmium-bearing filler materials...
40 CFR 60.2970 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What is an air curtain incinerator? 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2970 What is an air curtain incinerator? (a) An air curtain incinerator operates by forcefully projecting a curtain of air...
ERIC Educational Resources Information Center
Poitras, Adrian W., Ed.
1976-01-01
Listed are a number of materials including a spectrophotometer, power meter, vacuum pump, fume hood, cart system, and others. The source of the product and a brief description are given for each. (RH)
ERIC Educational Resources Information Center
Poitras, Adrian W., Ed.
1979-01-01
Reviews new science equipment and products for the laboratory. Includes hand-held calculators, fiberglass fume hoods, motorized microtomy, disposable mouse cages, and electric timers. Describes 11 products total. Provides manufacturer name, address, and price. (MA)
10 CFR 433.5 - Performance level determination.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) Each Federal agency shall consider laboratory fume hoods and kitchen ventilation systems as part of the ASHRAE-covered HVAC loads subject to the 30 percent savings requirements, rather than as process loads. ...
10 CFR 433.5 - Performance level determination.
Code of Federal Regulations, 2014 CFR
2014-01-01
... loads). (b) Each Federal agency shall consider laboratory fume hoods and kitchen ventilation systems as part of the ASHRAE-covered HVAC loads subject to the 30 percent savings requirements, rather than as...
10 CFR 433.5 - Performance level determination.
Code of Federal Regulations, 2011 CFR
2011-01-01
...) Each Federal agency shall consider laboratory fume hoods and kitchen ventilation systems as part of the ASHRAE-covered HVAC loads subject to the 30 percent savings requirements, rather than as process loads. ...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator combusts...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator combusts...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator combusts...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator combusts...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1445 Section 60.1445 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1445 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If your air curtain incinerator combusts...
Increased levels of oxidative DNA damage attributable to cooking-oil fumes exposure among cooks.
Ke, Yuebin; Cheng, Jinquan; Zhang, Zhicheng; Zhang, Renli; Zhang, Zhunzhen; Shuai, Zhihong; Wu, Tangchun
2009-07-01
Previous investigations have indicated that cooks are exposed to polycyclic aromatic hydrocarbons (PAHs) from cooking-oil fumes. However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene(1-OHP), a biological marker for PAH exposure. Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36); all were male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 h prior to sampling was estimated from questionnaires. The urine samples were frozen for later analyses of 8-OHdG and 1-OHP levels by high-performance liquid chromatography. Excretion in urine of 8-OHdG was similar for controls (mean 1.2micromol/mol creatinine, n = 36), and for those who had been in the kitchen with an exhaust-hood operating (mean 1.5micromol/mol creatinine, n = 45). Cooks exposed to cooking-oil fumes without exhaust-hood operation had significantly increased excretion of 8-OHdG (mean 2.3micromol/mol creatinine, n = 18), compared with controls. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis. The results indicate that exposure to PAH or possibly other compounds in cooking-oil fumes may cause oxidative DNA damage.
40 CFR 62.14765 - What is an air curtain incinerator?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14765 What is an air curtain incinerator? An air curtain incinerator...
40 CFR 62.14765 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14765 What is an air curtain incinerator? An air curtain incinerator...
40 CFR 62.14765 - What is an air curtain incinerator?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14765 What is an air curtain incinerator? An air curtain incinerator...
40 CFR 62.14765 - What is an air curtain incinerator?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14765 What is an air curtain incinerator? An air curtain incinerator...
40 CFR 62.14765 - What is an air curtain incinerator?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14765 What is an air curtain incinerator? An air curtain incinerator...
Verification of CFD model of plane jet used for smoke free zone separation in case of fire
NASA Astrophysics Data System (ADS)
Krajewski, Grzegorz; Suchy, Przemysław
2018-01-01
This paper presents the basic information about the use of air curtains in fire safety, as a barrier for heat and smoke. Mathematical model of an air curtain presented hereallows estimation of velocity of air in various points of space, including the velocity of air from an angled air curtain. Presented equations show how various parameters influence the performance of air curtain. Further, authors present results of their air curtain performance. Authors of that article have done tests in a real scale model. Tests results were used to verify chosen turbulence model and boundary conditions. Results of new studies are presented with regards to the performance of air curtain in case of fire, and final remarks on its design are given.
Local ventilation solution for large, warm emission sources.
Kulmala, Ilpo; Hynynen, Pasi; Welling, Irma; Säämänen, Arto
2007-01-01
In a foundry casting line, contaminants are released from a large area. Casting fumes include both volatile and particulate compounds. The volatile fraction contains hydrocarbons, whereas the particulate fraction mostly comprises a mixture of vaporized metal fumes. Casting fumes lower the air quality in foundries. The design of local ventilation for the casting area is a challenging task, because of the large casting area and convection plumes from warm moulds. A local ventilation solution for the mould casting area was designed and dimensioned with the aid of computational fluid dynamic (CFD) calculations. According to the calculations, the most efficient solution was a push-pull ventilation system. The prototype of the push-pull system was built and tested in actual operation at the foundry. The push flow was generated by a free plane jet that blew across the 10 m wide casting area towards an exhaust hood on the opposite side of the casting lines. The capture efficiency of the prototype was determined by the tracer gas method. The measured capture efficiencies with push jet varied between 40 and 80%, depending on the distance between the source and the exhaust. With the aid of the push flow, the average capture efficiency was increased from 40 (without jet) to 60%.
Stuke, Lance E; Nirula, Raminder; Gentilello, Larry M; Shafi, Shahid
2010-10-01
More than 9,000 vehicle occupants die each year in side-impact vehicle collisions, primarily from head injuries. The authors hypothesized that side-curtain air bags significantly improve head and neck safety in side-impact crash testing. Side-impact crash-test data were obtained from the Insurance Institute for Highway Safety, which ranks occupant protection as good, acceptable, marginal, or poor. Vehicles of the same make and model that underwent side-impact crash testing both with and without side-curtain air bags were compared, as well as the protective effect of these air bags on occupants' risk for head and neck injury. Of all the passenger vehicles, 25 models have undergone side-impact crash testing with and without side-curtain air bags by the Insurance Institute for Highway Safety. Only 3 models without side-curtain air bags (12%) provided good head and neck protection for drivers, while 21 cars with side-curtain air bags (84%) provided good protection (P < .001). For rear passengers, the added protection from side-curtain air bags was less dramatic but significant (84% without vs 100% with side-curtain air bags, P = .04). Side-curtain air bags significantly improve vehicle occupant safety in side-impact crash tests. Installation of these air bags should be federally mandated in all passenger vehicles. Copyright © 2010 Elsevier Inc. All rights reserved.
9. LOOKING NORTH IN BOP SHOP ON SERVICE FLOOR OF ...
9. LOOKING NORTH IN BOP SHOP ON SERVICE FLOOR OF FURNACE AISLE AT FUME HOOD SHOWING COLLAR AND ENTRANCE FOR OXYGEN LANCES. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA
38. DETAIL OF COOLING WATER BOOSTER PUMP FOR OXYGEN FURNACES, ...
38. DETAIL OF COOLING WATER BOOSTER PUMP FOR OXYGEN FURNACES, LANCES, AND FUME HOODS IN THE GAS WASHER PUMP HOUSE LOOKING EAST. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA
40 CFR 60.3062 - What is an air curtain incinerator?
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain of air across an open, integrated combustion chamber (fire box) or open pit or trench (trench... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What is an air curtain incinerator? 60... Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3062 What is...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1455 Section 60... Reconstruction is Commenced After June 6, 2001 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1455 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100...
Code of Federal Regulations, 2014 CFR
2014-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1455 Section 60... Reconstruction is Commenced After June 6, 2001 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1455 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100...
Code of Federal Regulations, 2014 CFR
2014-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3068 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3068 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1455 Section 60... Reconstruction is Commenced After June 6, 2001 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1455 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3068 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2010 CFR
2010-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1455 Section 60... Reconstruction is Commenced After June 6, 2001 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1455 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reporting requirements for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or... Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood... for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? (a...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Qualification Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2973 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2011 CFR
2011-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1455 Section 60... Reconstruction is Commenced After June 6, 2001 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1455 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100...
Code of Federal Regulations, 2014 CFR
2014-07-01
... reporting requirements for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or... Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood... for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? (a...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reporting requirements for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or... Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood... for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? (a...
Code of Federal Regulations, 2010 CFR
2010-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3068 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2011 CFR
2011-07-01
... reporting requirements for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or... Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood... for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? (a...
Code of Federal Regulations, 2011 CFR
2011-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3068 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2010 CFR
2010-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Qualification Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2973 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2011 CFR
2011-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Qualification Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2973 What are the recordkeeping and reporting requirements for air curtain incinerators that burn only wood...
Code of Federal Regulations, 2010 CFR
2010-07-01
... reporting requirements for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or... Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood... for air curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? (a...
Code of Federal Regulations, 2013 CFR
2013-07-01
... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Modification or Reconstruction is Commenced on or After June 16, 2006 Air Curtain Incinerators That Burn Only... requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Prior to...
Code of Federal Regulations, 2014 CFR
2014-07-01
... reporting requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste... Modification or Reconstruction is Commenced on or After June 16, 2006 Air Curtain Incinerators That Burn Only... requirements for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Prior to...
Code of Federal Regulations, 2012 CFR
2012-07-01
... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100...
Code of Federal Regulations, 2014 CFR
2014-07-01
... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14815 What are the emission limitations for air curtain incinerators that burn 100...
Code of Federal Regulations, 2012 CFR
2012-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... and Qualification Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2014 CFR
2014-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Reconstruction is Commenced on or After June 16, 2006 Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn...
Code of Federal Regulations, 2013 CFR
2013-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Reconstruction is Commenced on or After June 16, 2006 Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn...
Code of Federal Regulations, 2013 CFR
2013-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2014 CFR
2014-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2012 CFR
2012-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2010 CFR
2010-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2011 CFR
2011-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... and Qualification Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2011 CFR
2011-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Code of Federal Regulations, 2010 CFR
2010-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... and Qualification Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste... incinerator that burns only wood waste, clean lumber, and yard waste? Yes, if your air curtain incinerator is...
Flow and performance of an air-curtain biological safety cabinet.
Huang, Rong Fung; Chou, Chun I
2009-06-01
Using laser-assisted smoke flow visualization and tracer gas concentration detection techniques, this study examines aerodynamic flow properties and the characteristics of escape from containment, inward dispersion, and cross-cabinet contamination of a biological safety cabinet installed with an air curtain across the front aperture. The experimental method partially simulates the NSF/ANSI 49 standards with the difference that the biological tracer recommended by these standards is replaced by a mixture of 10% SF(6) in N(2). The air curtain is set up across the cabinet aperture plane by means of a narrow planar jet issued from the lower edge of the sash and a suction flow going through a suction slot installed at the front edge of the work surface. Varying the combination of jet velocity, suction flow velocity, and descending flow velocity reveals three types of characteristic flow modes: 'straight curtain', 'slightly concave curtain', and 'severely concave curtain'. Operating the cabinet in the straight curtain mode causes the air curtain to impinge on the doorsill and therefore induces serious escape from containment. In the severely concave curtain mode, drastically large inward dispersion and cross-cabinet contamination were observed because environmental air entered into the cabinet and a three-dimensional vortical flow structure formed in the cabinet. The slightly concave curtain mode presents a smooth and two-dimensional flow pattern with an air curtain separating the outside atmosphere from the inside space of the cabinet, and therefore exhibited negligibly small escape from containment, inward dispersion, and cross-cabinet contamination.
Code of Federal Regulations, 2013 CFR
2013-07-01
... close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and not..., 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3065 What must I do if I plan to permanently close my air curtain incinerator that burns only wood...
Code of Federal Regulations, 2012 CFR
2012-07-01
... close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and not..., 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3065 What must I do if I plan to permanently close my air curtain incinerator that burns only wood...
Code of Federal Regulations, 2014 CFR
2014-07-01
... close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and not..., 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3065 What must I do if I plan to permanently close my air curtain incinerator that burns only wood...
Code of Federal Regulations, 2010 CFR
2010-07-01
... close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and not..., 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3065 What must I do if I plan to permanently close my air curtain incinerator that burns only wood...
Code of Federal Regulations, 2011 CFR
2011-07-01
... close my air curtain incinerator that burns only wood waste, clean lumber, and yard waste and not..., 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3065 What must I do if I plan to permanently close my air curtain incinerator that burns only wood...
40 CFR 62.15365 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... incinerator? An air curtain incinerator operates by forcefully projecting a curtain of air across an open chamber or open pit in which combustion occurs. Incinerators of this type can be constructed above or...
40 CFR 60.1435 - What is an air curtain incinerator?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Waste Combustion Units for Which Construction is Commenced After August 30, 1999 or for Which... Yard Waste § 60.1435 What is an air curtain incinerator? An air curtain incinerator operates by...
40 CFR 60.1435 - What is an air curtain incinerator?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Waste Combustion Units for Which Construction is Commenced After August 30, 1999 or for Which... Yard Waste § 60.1435 What is an air curtain incinerator? An air curtain incinerator operates by...
40 CFR 60.1435 - What is an air curtain incinerator?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Waste Combustion Units for Which Construction is Commenced After August 30, 1999 or for Which... Yard Waste § 60.1435 What is an air curtain incinerator? An air curtain incinerator operates by...
40 CFR 60.1435 - What is an air curtain incinerator?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Waste Combustion Units for Which Construction is Commenced After August 30, 1999 or for Which... Yard Waste § 60.1435 What is an air curtain incinerator? An air curtain incinerator operates by...
40 CFR 60.2970 - What is an air curtain incinerator?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2970 What is an air... incinerators include both firebox and trench burner units. (b) Air curtain incinerators that burn only the...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15380 Section 62.15380 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15380 How must I monitor opacity for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15380 Section 62.15380 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15380 How must I monitor opacity for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1925 Section 60.1925 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1925 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1925 Section 60.1925 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1925 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15380 Section 62.15380 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15380 How must I monitor opacity for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1925 Section 60.1925 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1925 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use...
Code of Federal Regulations, 2014 CFR
2014-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15380 Section 62.15380 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15380 How must I monitor opacity for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2012 CFR
2012-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15380 Section 62.15380 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15380 How must I monitor opacity for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1925 Section 60.1925 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1925 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent yard waste? 62.15375 Section 62.15375 Protection of Environment... Combustion Units Constructed on or Before August 30, 1999 Air Curtain Incinerators That Burn 100 Percent Yard Waste § 62.15375 What are the emission limits for air curtain incinerators that burn 100 percent yard...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1925 Section 60.1925 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1925 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1920 Section 60.1920 Protection of Environment... or Before August 30, 1999 Model Rule-Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1920 What are the emission limits for air curtain incinerators that burn 100 percent yard waste? If...
Code of Federal Regulations, 2013 CFR
2013-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste...
Code of Federal Regulations, 2010 CFR
2010-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste...
Code of Federal Regulations, 2011 CFR
2011-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3066 Section 60... Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3066 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste...
Efficiency of an air curtain as an anti-insect barrier: the honey bee as a model insect.
Kairo, Guillaume; Pioz, Maryline; Tchamitchian, Sylvie; Pelissier, Michel; Brunet, Jean-Luc; Belzunces, Luc P
2018-05-28
Vector-borne diseases are of high concern for human, animal and plant health. In humans, such diseases are often transmitted by flying insects. Flying insects stop their flight when their kinetic energy cannot compensate for the wind speed. Here, the efficiency of an air curtain in preventing insects from entering a building was studied using the honey bee as a model. Bees were trained to visit a food source placed in a building. The air curtain was tested with strongly motivated bees, when the visiting activity was very high. Airflow velocity was modulated by setting an air curtain device at different voltages. At the nominal voltage, the anti-insect efficiency was 99.9 ± 0.2% compared with both the number of bees at a given time in the absence of the air curtain and the number of bees before the activation of the air curtain. The efficiency decreased as the airflow velocity decreased. The results show that an air curtain operating at an airflow velocity of 7.5 m/sec may prevent a strong flyer with high kinetic energy, such as the honey bee, from entering a building. Thus, air curtains offer an alternative approach for combating vector-borne diseases. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1450 Section 60.1450 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1450 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use EPA Reference Method 9 in appendix A of...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? 62.14820 Section... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14820 How must I monitor opacity for air curtain incinerators that burn 100 percent...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1450 Section 60.1450 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1450 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use EPA Reference Method 9 in appendix A of...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1450 Section 60.1450 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1450 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use EPA Reference Method 9 in appendix A of...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2972 Section 60.2972... Commenced on or After June 16, 2006 Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2972 How must I monitor opacity for air curtain incinerators that burn only wood waste...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2972 Section 60.2972... Commenced on or After June 16, 2006 Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2972 How must I monitor opacity for air curtain incinerators that burn only wood waste...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? 62.14820 Section... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14820 How must I monitor opacity for air curtain incinerators that burn 100 percent...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1450 Section 60.1450 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1450 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use EPA Reference Method 9 in appendix A of...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? 62.14820 Section... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14820 How must I monitor opacity for air curtain incinerators that burn 100 percent...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn 100 percent yard waste? 60.1450 Section 60.1450 Protection of Environment... Air Curtain Incinerators That Burn 100 Percent Yard Waste § 60.1450 How must I monitor opacity for air curtain incinerators that burn 100 percent yard waste? (a) Use EPA Reference Method 9 in appendix A of...
ERIC Educational Resources Information Center
Roy, Ken
2005-01-01
Asbestos has been used in the construction of elementary, middle, and high school ceilings, floor tile adhesives, pipe and structural beam insulations, science laboratory benches, wire gauss on ring stands, fume hood panels, general insulation, and more during the 1950s through early 1970s. Why? Primarily asbestos was selected because of its…
Accessibility: Maximum Mobility and Function.
ERIC Educational Resources Information Center
Smyser, Michael
2003-01-01
Describes how to design school and university labs to comply with Americans with Disabilities Act (ADA) standards, focusing on counter height for students in wheelchairs; appropriate knee space and sink height in sink areas; ADA-compliant fume hoods; accessible laboratory doors and entryways; and safety concerns (e.g., emergency eyewash stations…
2014-03-27
in a thin conductive layer, the wafer surface can be made into the cathode while using a stainless steel plate as an anode. Bath temperature, voltage...beakers with polytetrafluoroethylene (PTFE) tools while under a fume hood, as HF is known to attack glass and polystyrene [62]. Additionally
Protective supplied breathing air garment
Childers, Edward L.; von Hortenau, Erik F.
1984-07-10
A breathing air garment for isolating a wearer from hostile environments containing toxins or irritants includes a suit and a separate head protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit rear torso panel permits access into the suit and is sealed with an adhesive sealing flap.
Protective supplied-breathing-air garment
Childers, E.L.; von Hortenau, E.F.
1982-05-28
A breathing-air garment for isolating a wearer from hostile environments containing toxins or irritants is disclosed. The garment includes a suit and a separate head-protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air-delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air-delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit sealed with an adhesive sealing flap.
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerator that burns only wood waste, clean lumber, and yard waste and then restart it? 60.3064... Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3064 What must I do if I close my air curtain incinerator that burns only wood waste, clean lumber, and yard...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerator that burns only wood waste, clean lumber, and yard waste and then restart it? 60.3064... Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3064 What must I do if I close my air curtain incinerator that burns only wood waste, clean lumber, and yard...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerator that burns only wood waste, clean lumber, and yard waste and then restart it? 60.3064... Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3064 What must I do if I close my air curtain incinerator that burns only wood waste, clean lumber, and yard...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerator that burns only wood waste, clean lumber, and yard waste and then restart it? 60.3064... Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3064 What must I do if I close my air curtain incinerator that burns only wood waste, clean lumber, and yard...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerator that burns only wood waste, clean lumber, and yard waste and then restart it? 60.3064... Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3064 What must I do if I close my air curtain incinerator that burns only wood waste, clean lumber, and yard...
Protective supplied breathing air garment
Childers, E.L.; Hortenau, E.F. von.
1984-07-10
A breathing air garment is disclosed for isolating a wearer from hostile environments containing toxins or irritants includes a suit and a separate head protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit rear torso panel permits access into the suit and is sealed with an adhesive sealing flap. 17 figs.
Refinement of Propellant Strand Burning Method to Suit Aluminised Composite Rocket Propellant
2014-12-01
from discrete burn rates at each pressure. Strands are ignited with a nickel- chromium (nichrome) wire with burn time measured via timing wires which...Application of Paint Inhibitor 8.5.1 Switch on the fume hood and prepare a 70% dilution of inhibitor paint as per instructions of document 3.5
Soxhlet Extraction of Caffeine from Beverage Plants
NASA Astrophysics Data System (ADS)
Adam, D. J.; Mainwaring, J.; Quigley, Michael N.
1996-12-01
A simple procedure is described for the extraction of caffeine from coffee beans or granules, tea leaves, mat leaves, etc. Since dichloromethane and several other hazardous substances are used, the procedure is best performed in a fume hood. Following extraction, melting point determination of the crystalline precipitate establishes its positive identity. Includes 33 references.
Controlling allergens in animal rooms by using curtains.
Krohn, Thomas C; Itter, Gabi; Fosse, Richard; Hansen, Axel K
2006-05-01
The reduction and control of allergens in the animal facility is important for staff working with laboratory animals. This study was designed to evaluate the efficiency of perforated Makrolon curtains in front of racks as a method to reduce the amount of allergen in the animal room. The experimental situation we studied provides some information regarding allergen disposition in animal rooms but is clearly artificial and does not reflect a typical, 'real-world' environment in terms of preventing exposure of workers to allergens. Plastic curtains with holes were placed in front of racks, and a corridor between the racks and a curtain was present. The room was ventilated with air, which was blown into the room through the middle of the corridor, flowing downstream and passing through the holes in the curtain. This set-up resulted in air flow from the corridor through the curtain. Air samples were collected from sites in the corridor and behind the curtain. The samples were analyzed for the allergen Mus m1, and the amount of allergen was calculated. The results show air flow from the aisle through the holes in the curtains and through the racks behind the curtains, and this flow keeps allergen behind the curtains and prevents its spread from the cages into the aisle. The present study shows that the use of curtains in front of the cage racks is an efficient way to prevent spread of allergens from rodent cages to the entire animal room.
Beneficial outcomes of the air curtain project in Ghana, August 14-27, 2011
USDA-ARS?s Scientific Manuscript database
A number of questions existed about the feasibility of using the air curtain system in West Africa and after the project was completed many of the questions had been answered. Air curtains can be securely mounted on the truck mounted stairs used for passenger planning and deplaning. The Accra Airpor...
42 CFR 84.140 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 1 2011-10-01 2011-10-01 false Air velocity and noise levels; hoods and helmets... PROTECTIVE DEVICES Supplied-Air Respirators § 84.140 Air velocity and noise levels; hoods and helmets; minimum requirements. Noise levels generated by the respirator will be measured inside the hood or helmet...
42 CFR 84.140 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Air velocity and noise levels; hoods and helmets... PROTECTIVE DEVICES Supplied-Air Respirators § 84.140 Air velocity and noise levels; hoods and helmets; minimum requirements. Noise levels generated by the respirator will be measured inside the hood or helmet...
Code of Federal Regulations, 2014 CFR
2014-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1930 Section 60... Incinerators That Burn 100 Percent Yard Waste § 60.1930 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 62.15385 Section 62... Incinerators That Burn 100 Percent Yard Waste § 62.15385 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2012 CFR
2012-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1930 Section 60... Incinerators That Burn 100 Percent Yard Waste § 60.1930 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2014 CFR
2014-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 62.15385 Section 62... Incinerators That Burn 100 Percent Yard Waste § 62.15385 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2011 CFR
2011-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 62.15385 Section 62... Incinerators That Burn 100 Percent Yard Waste § 62.15385 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 62.15385 Section 62... Incinerators That Burn 100 Percent Yard Waste § 62.15385 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2010 CFR
2010-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 62.15385 Section 62... Incinerators That Burn 100 Percent Yard Waste § 62.15385 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2010 CFR
2010-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1930 Section 60... Incinerators That Burn 100 Percent Yard Waste § 60.1930 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2011 CFR
2011-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1930 Section 60... Incinerators That Burn 100 Percent Yard Waste § 60.1930 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
Code of Federal Regulations, 2013 CFR
2013-07-01
... reporting requirements for air curtain incinerators that burn 100 percent yard waste? 60.1930 Section 60... Incinerators That Burn 100 Percent Yard Waste § 60.1930 What are the recordkeeping and reporting requirements for air curtain incinerators that burn 100 percent yard waste? (a) Provide a notice of construction...
People and Policy Strategies | Climate Neutral Research Campuses | NREL
People and Policy Strategies People and Policy Strategies Strategies that impact human behavior and Work Strategies Land Use Space Management Space Planning and Use Energy conservation policies encourage building occupants to turn off lights and computers, close fume hoods, limit appliance use in offices, and
Code of Federal Regulations, 2012 CFR
2012-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Within...
Code of Federal Regulations, 2011 CFR
2011-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Within...
Code of Federal Regulations, 2010 CFR
2010-07-01
... air curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2971 Section 60... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2971 What are the emission limitations for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Within...
42 CFR 84.202 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 1 2011-10-01 2011-10-01 false Air velocity and noise levels; hoods and helmets... PROTECTIVE DEVICES Chemical Cartridge Respirators § 84.202 Air velocity and noise levels; hoods and helmets; minimum requirements. Noise levels generated by the respirator will be measured inside the hood or helmet...
42 CFR 84.202 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Air velocity and noise levels; hoods and helmets... PROTECTIVE DEVICES Chemical Cartridge Respirators § 84.202 Air velocity and noise levels; hoods and helmets; minimum requirements. Noise levels generated by the respirator will be measured inside the hood or helmet...
Code of Federal Regulations, 2011 CFR
2011-07-01
... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or... percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity is...
Code of Federal Regulations, 2010 CFR
2010-07-01
... air curtain incinerators that burn 100 percent wood wastes, clean lumber and/or yard waste? 62.14815... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or... percent wood wastes, clean lumber and/or yard waste? (a) After the date the initial test for opacity is...
Air curtain development: an energy harvesting solution for hinged doors
NASA Astrophysics Data System (ADS)
Dayal, Vineed; Lee, Soobum
2017-04-01
The paper proposes a fully mechanical air curtain system that will be powered solely by harvested energy from common hinged doors. The average person uses this type of door several times a day with an almost unconscious amount of applied force and effort. This leads to a high potential of energy to be harvested in doorways that see high traffic and frequent operation7 . Frequently opened door entry ways have always been regarded as a major element that causes significant energy loss and contaminated air conditions in buildings6 . Private companies, particularly those with warehouses, have introduced commercial electrical air curtains to block the open entrances from invading cold air11. This project intends to introduce an original design of air curtain which operates fans only when the door opens and closes, by directly converting door motion to fan rotation without any electronic motor or power cable. The air stream created by this device will prevent the transfer of outside air and contaminants. Research will be conducted to determine the most efficient method of harvesting energy from door use, and the prototyping process will be conducted to meet the required performance of current air curtain models.
Code of Federal Regulations, 2014 CFR
2014-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2974 Am I required to apply for and obtain a title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber...
Code of Federal Regulations, 2013 CFR
2013-07-01
... title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber, and... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.2974 Am I required to apply for and obtain a title V operating permit for my air curtain incinerator that burns only wood waste, clean lumber...
2015-05-01
with a 0.45 µm Millipore Durapore PVDF (polyvinylidene fluoride) filter (13 mm diam.) in a Luer filter holder attached to a stainless steel Luer...were recorded. All extractions were performed in a fume hood. DI water (5 mL) was added to each of the test tubes containing supernatant and the new
Ke, Yue-bin; Xu, Xin-yun; Yuan, Jian-hui; Fang, Shi-song; Liu, Yi-min; Wu, Tang-chun
2010-08-01
Previous investigations indicate that cooks are exposed to polycyclic aromatic hydrocarbons (PAH) from cooking oil fumes (COF). However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene (1-OHP), a biological marker for PAH exposure. Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36), all are male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8-OHdG and 1-OHP by high performance liquid chromatography. Excretion in urine of 8-OHdG were similar for controls (mean 1.2 µmol/mol creatinine, n = 36), and for those who had been in the kitchen room with exhaust hood operation (mean 1.5 µmol/mol creatinine, n = 45). COF exposed cooks without exhaust hood operation had increased excretion of 8-OHdG (mean 2.3 µmol/mol creatinine, n = 18). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis. Results indicate that exposure to PAH or possibly other compounds in COF may cause oxidative DNA damage.
Code of Federal Regulations, 2012 CFR
2012-07-01
... obtains filters with a lead content of 75 µg/filter. It is important that the variation in lead content... important to keep the sample covered so that corrosion products—formed on fume hood surfaces which may... National Science Foundation for publications, 1976. 3. Zdrojewski, A. et al. “The Accurate Measurement of...
Code of Federal Regulations, 2011 CFR
2011-07-01
... obtains filters with a lead content of 75 µg/filter. It is important that the variation in lead content... important to keep the sample covered so that corrosion products—formed on fume hood surfaces which may... National Science Foundation for publications, 1976. 3. Zdrojewski, A. et al. “The Accurate Measurement of...
Code of Federal Regulations, 2013 CFR
2013-07-01
... obtains filters with a lead content of 75 µg/filter. It is important that the variation in lead content... important to keep the sample covered so that corrosion products—formed on fume hood surfaces which may... National Science Foundation for publications, 1976. 3. Zdrojewski, A. et al. “The Accurate Measurement of...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2972 Section 60.2972... PERFORMANCE FOR NEW STATIONARY SOURCES Operator Training and Qualification Air Curtain Incinerators That Burn... incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of appendix A of this...
Code of Federal Regulations, 2014 CFR
2014-07-01
... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY... Units Model Rule-Air Curtain Incinerators § 60.2855 What must I do if I plan to permanently close my air...
Code of Federal Regulations, 2014 CFR
2014-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3067 Section 60.3067... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3067 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of...
Code of Federal Regulations, 2012 CFR
2012-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3067 Section 60.3067... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3067 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of...
Code of Federal Regulations, 2013 CFR
2013-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3067 Section 60.3067... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3067 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3067 Section 60.3067... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3067 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.3067 Section 60.3067... Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3067 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? 62.14820 Section... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or... wood wastes, clean lumber, and/or yard waste? (a) Use Method 9 of 40 CFR part 60, Appendix A to...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn 100 percent wood wastes, clean lumber, and/or yard waste? 62.14820 Section... Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or... wood wastes, clean lumber, and/or yard waste? (a) Use Method 9 of 40 CFR part 60, Appendix A to...
40 CFR 60.2810 - What is an air curtain incinerator?
Code of Federal Regulations, 2014 CFR
2014-07-01
... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model Rule-Air Curtain Incinerators § 60.2810 What...
40 CFR 60.1435 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Small Municipal... forcefully projecting a curtain of air across an open chamber or open pit in which combustion occurs...
ELECTRIC CURTAIN DEVICE FOR CONTROL AND REMOVAL OF FINE PARTICLES
The report gives results of an evaluation of an electric curtain for the purpose of particulate control and removal. If the particles are charged by corona, the curtain will stop them only in a very slow air flow (less than 2 cm/sec). At these slow flows, a vertical curtain would...
2013-02-01
November 2012 phosphorus, and vitamin B12. Additionally a reductant reacts directly with hexavalent chromium to reduce it to the trivalent state. SRS...being operated under continuous flow conditions in the laboratory. Entire assembly takes up approximately 5 sq. ft. in a fume hood. . 44 Figure 5-3...61 Figure 5-16. Hexavalent Chromium detected in ISMA effluent post in situ incubation
40 CFR 60.1910 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for... incinerator operates by forcefully projecting a curtain of air across an open chamber or open pit in which...
Code of Federal Regulations, 2010 CFR
2010-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2972 Section 60.2972... Only Wood Waste, Clean Lumber, and Yard Waste § 60.2972 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of appendix A of this...
Code of Federal Regulations, 2011 CFR
2011-07-01
... curtain incinerators that burn only wood waste, clean lumber, and yard waste? 60.2972 Section 60.2972... Only Wood Waste, Clean Lumber, and Yard Waste § 60.2972 How must I monitor opacity for air curtain incinerators that burn only wood waste, clean lumber, and yard waste? (a) Use Method 9 of appendix A of this...
Evaluation of operational parameters role on the emission of fumes.
Sajedifar, Javad; Kokabi, Amir Hossein; Farhang Dehghan, Somayeh; Mehri, Ahmad; Azam, Kamal; Golbabaei, Farideh
2017-12-12
Electric arc welding is a routine operation in the construction of metallic structures, but the fumes generated during the welding process can threaten the health of welders. Fumes are undesirable products of the majority of welding operations and may have various detrimental effects on health. The purpose of this study was to investigate the effect of operational parameters of the shielded metal arc welding (SMAW) process on the emission of fumes. A dust monitor was used to measure the number and mass concentration of fumes generated by SMAW. Measurements were made at the distances of 23cm (hood inlet) and 41cm (welder\\'s breathing zone) from the weld point, with different values assigned to three operational parameters, namely current intensity, travel speed, and heat input (HI). Number concentration (NC) decreased with the increase in particle size. The highest mass concentrations (MC) were observed for MC1 (0.35μm-0.5μm) and MC8 (Larger than 6.5μm). For reducing exposures to fumes, welders are recommended to use the lowest voltage and amperage and the highest travel speed to the extent that does not compromise in the quality of welds. For assessment of exposure to airborne particles in industrial workplaces and specially in welding operations, it is thought that taking, solely, mass concentration in to consideration and lack of attention to number concentration would not be able to reflect accurate assessment of the adverse effects of particles on the body organs.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-28
... that many vehicles will depend on side impact air bag technology to meet all of the injury criteria of... ``lead to the installation of new technologies, such as side curtain air bags and torso side air bags... is side air bag technology incorporated in the vehicle's roof rail (side air bag curtain), door, and...
40 CFR 60.2810 - What is an air curtain incinerator?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30... conventional combustion devices with enclosed fireboxes and controlled air technology such as mass burn... “Air Curtain Incinerators” (§§ 60.2810 through 60.2870). (1) 100 percent wood waste. (2) 100 percent...
40 CFR 60.2970 - What is an air curtain incinerator?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Waste Incineration Units for Which Construction is Commenced After December 9, 2004, or for Which... Wood Waste, Clean Lumber, and Yard Waste § 60.2970 What is an air curtain incinerator? (a) An air... through 60.2974 and are exempt from all other requirements of this subpart. (1) 100 percent wood waste. (2...
40 CFR 60.2970 - What is an air curtain incinerator?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Waste Incineration Units for Which Construction is Commenced After December 9, 2004, or for Which... Wood Waste, Clean Lumber, and Yard Waste § 60.2970 What is an air curtain incinerator? (a) An air... through 60.2974 and are exempt from all other requirements of this subpart. (1) 100 percent wood waste. (2...
Fabrication and Optimization of Carbon Nanomaterial-Based Lithium-Ion Battery Anodes
2012-03-01
preparation setup under the fume hood with NMP solvent, glass pipette with dispenser, and the ball milled powder mixture containing LiFePO4 , acetylene...minutes. ............................................................................. 18 Figure 12. (a) LiFePO4 slurry applied on foil current collector...and (b) LiFePO4 slurry casted with applicator and (c) LiFePO4 casted (From [15])....... 18 Figure 13. MTI disc cutter used to cut individual
Grazing-Angle Fourier Transform Infrared Spectroscopy for Surface Cleanliness Verification
2003-03-01
coating. 34 North Island personnel were also interested in using the portable FTIR instrument to detect a trivalent chromium conversion coating on... trivalent chromium coating on aluminum panels. 35 Following the successful field-test at NADEP North Island in December 2000, a second demonstration of...contaminated, the panels were allowed to dry under a fume hood to evaporate the solvent. They were then placed in a desiccator for final drying. This
Effect of Rheological Properties on Liquid Curtain Coating
NASA Astrophysics Data System (ADS)
Mohammad Karim, Alireza; Suszynski, Wieslaw; Griffith, William; Pujari, Saswati; Carvalho, Marcio; Francis, Lorraine; Dow Chemical Company Collaboration; PUC-Rio Collaboration
2017-11-01
Curtain coating is one of the preferred methods for high-speed precision application of single-layer and multi-layer coatings in technology. However, uniform coatings are only obtained in a certain range of operating parameters, called coating window. The two main physical mechanisms that limit successful curtain coating are liquid curtain breakup and air entrainment. The rheological properties of the liquid play an important role on these mechanisms, but the fundamental understanding of these relations is still not complete. The effect of rate-dependent shear and extensional viscosities on the stability of viscoelastic and shear thinning liquid curtains were explored by high-speed visualization. Aqueous solutions of polyethylene oxide (PEO) and polyethylene glycol (PEG) were used as viscoelastic liquids. Xanthan Gum in water and glycerol solutions with a range of compositions were used as shear thinning liquids. The critical condition was determined by examining flow rate below which curtain broke. In this work, we also analyze relative importance of rate-dependent shear and extensional viscosity on both curtain breakup and air entrainment. We would like to acknowledge the financial support from the Dow Chemical Company.
Characterization of volatile organic compounds from different cooking emissions
NASA Astrophysics Data System (ADS)
Cheng, Shuiyuan; Wang, Gang; Lang, Jianlei; Wen, Wei; Wang, Xiaoqi; Yao, Sen
2016-11-01
Cooking fume is regarded as one of the main sources of urban atmospheric volatile organic compounds (VOCs) and its chemical characteristics would be different among various cooking styles. In this study, VOCs emitted from four different Chinese cooking styles were collected. VOCs concentrations and emission characteristics were analyzed. The results demonstrated that Barbecue gave the highest VOCs concentrations (3494 ± 1042 μg/m3), followed by Hunan cuisine (494.3 ± 288.8 μg/m3), Home cooking (487.2 ± 139.5 μg/m3), and Shandong cuisine (257.5 ± 98.0 μg/m3). The volume of air drawn through the collection hood over the stove would have a large impact on VOCs concentration in the exhaust. Therefore, VOCs emission rates (ER) and emission factors (EF) were also estimated. Home cooking had the highest ER levels (12.2 kg/a) and Barbecue had the highest EF levels (0.041 g/kg). The abundance of alkanes was higher in Home cooking, Shandong cuisine and Hunan cuisine with the value of 59.4%-63.8%, while Barbecue was mainly composed of alkanes (34.7%) and alkenes (39.9%). The sensitivity species of Home cooking and Hunan cuisine were alkanes, and that of Shandong cuisine and Barbecue were alkenes. The degree of stench pollution from cooking fume was lighter.
Code of Federal Regulations, 2010 CFR
2010-07-01
... to combust debris from a disaster or emergency such as a tornado, hurricane, flood, ice storm, high winds, or act of bioterrorism. To qualify for this exclusion, the incinerator or air curtain incinerator...
40 CFR 60.2865 - How must I monitor opacity for air curtain incinerators?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 6 2010-07-01 2010-07-01 false How must I monitor opacity for air curtain incinerators? 60.2865 Section 60.2865 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and...
40 CFR 60.2865 - How must I monitor opacity for air curtain incinerators?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 6 2011-07-01 2011-07-01 false How must I monitor opacity for air curtain incinerators? 60.2865 Section 60.2865 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and...
40 CFR 60.2255 - How must I monitor opacity for air curtain incinerators?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 6 2011-07-01 2011-07-01 false How must I monitor opacity for air curtain incinerators? 60.2255 Section 60.2255 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Commercial and Industrial Solid...
40 CFR 60.2255 - How must I monitor opacity for air curtain incinerators?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 6 2010-07-01 2010-07-01 false How must I monitor opacity for air curtain incinerators? 60.2255 Section 60.2255 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Commercial and Industrial Solid...
Fabrication, Characterization, and Energetic Properties of Metallized Nanofibers
2013-12-31
to reduce the chance of spark ignition while electrospinning, a low working voltage of 12- 15 kV, is applied to a stainless steel needle (17-27...solution as a solid block within 12-24 h. An in-house electrospinning setup in a fume hood is used to electrospin the metalized suspension equipped...rolled to obtain a cylindrical cross section along the length of the fiber. These samples were then placed inside a steel combustion chamber (48 x 48
Preparation, Characterization, and Energetic Properties of Metallized Nanofibers
2013-12-31
applied to a stainless steel needle (17-27 gauge) thereby charging the n AI/PFPE loaded PS/ DMF suspension. The syringe pump is set at a flow rate of...front propagates to the left. rolled to obtain a cylindrical cross section along the length of the fiber. These samples were then placed inside a steel ...occur altering the transJerred mass balance during electro spinning. Fiber Spinning. An in house electrospinning setup in a fume hood is used to
EMISSIONS FROM THE BURNING OF VEGETATIVE DEBRIS IN AIR CURTAIN DESTRUCTORS
Although no data has been published on emissions from construction and demolition (C&D) debris burned in an air curtain destructor (ACD), a few studies provide information on emissions from combustion of vegetative debris. These results are compared to studies of open burning of...
Comparison of heat transfer and soil impacts of air curtain burner burning and slash pile burning
Woongsoon Jang; Deborah S. Page-Dumroese; Han-Sup Han
2017-01-01
We measured soil heating and subsequent changes in soil properties between two forest residue disposal methods: slash pile burning (SPB) and air curtain burner (ACB). The ACB consumes fuels more efficiently and safely via blowing air into a burning container. Five burning trials with different fuel sizes were implemented in northern California, USA. Soil temperature...
40 CFR 62.14805 - What must I do if I close my air curtain incinerator and then restart it?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14805 What must I do if I close my...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14810 What must I do if I...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14810 What must I do if I...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14810 What must I do if I...
Code of Federal Regulations, 2014 CFR
2014-07-01
... Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14810 What must I do if I...
Code of Federal Regulations, 2013 CFR
2013-07-01
... Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14810 What must I do if I...
Effect of Elasticity on Stability of Viscoelastic Liquid Curtain
NASA Astrophysics Data System (ADS)
Mohammad Karim, Alireza; Suszynski, Wieslaw; Francis, Lorraine; Carvalho, Marcio; University of Minnesota, Twin Cities Collaboration; Pontifícia Universidade Católica do Rio de Janeiro Collaboration; Dow Chemical Company Collaboration
2016-11-01
Curtain coating is one the preferred methods for high-speed precision application of single-layer and multi-layer coatings in industry. Despite the extensive variety of applications of curtain coating, its operation is challenging and uniform coating is only obtained in a certain range of operating parameters, called the coating window. The two main physical mechanisms that limit curtain coating are the breakup of the liquid curtain, below a critical flow rate, and the catastrophic event of air entrainment, which occurs above a certain web speed. The rheological characteristics of the coating liquid play an important role on these mechanisms, but the fundamental understanding of the role of rheology is still not complete. In this work, we analyze the relative importance of shear and extensional viscosity on both curtain breakup and dynamic contact line instability (i.e. air entrainment). Aqueous solutions of polyethylene oxide (PEO) and polyethylene glycol (PEG) of different molecular weights were used as model liquids to obtain fluids with different levels of extensional thickening behavior. We would like to acknowledge the financial support from the Dow Chemical Company.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
A hazard evaluation and technical assistance survey of the biology-botany science building at the University of Oregon, Corvallis Campus to determine a possible etiologic agent responsible for nervous-system complaints among employees was conducted. Upon occupation of the new building formerly healthy plants transplanted to the new laboratories died. Since that time, a plant pathologist died of a neurological disease and three other professors contracted a similar progressive neurological disease. The ventilation system of the building was studied. Fume-hood rates were measured and air-inlet filters were analyzed. In addition, medical interviews of employees were conducted, medical histories obtained, and consultations withmore » their physicians held. If there is a single process endemic among the present staff, it could not be identified, although there are definitely similarities in complaints. No pathophysiological link between the fatal neurological diseases and current complaints among the staff was found. No clear-cut etiologic relationship between the work environment and symptoms was apparent.« less
Inflammatory Markers in Blood and Exhaled Air after Short-Term Exposure to Cooking Fumes
Svedahl, Sindre Rabben
2013-01-01
Objectives: Cooking fumes contain aldehydes, alkanoic acids, polycyclic aromatic hydrocarbons, and heterocyclic compounds. The inhalation of cooking fumes entails a risk of deleterious health effects. The aim of this study was to see if the inhalation of cooking fumes alters the expression of inflammatory reactions in the bronchial mucosa and its subsequent systemic inflammatory response in blood biomarkers. Methods: Twenty-four healthy volunteers stayed in a model kitchen on two different occasions for 2 or 4h. On the first occasion, there was only exposure to normal air, and on the second, there was exposure to controlled levels of cooking fumes. On each occasion, samples of blood, exhaled air, and exhaled breath condensate (EBC) were taken three times in 24h and inflammatory markers were measured from all samples. Results: There was an increase in the concentration of the d-dimer in blood from 0.27 to 0.28mg ml–1 on the morning after exposure to cooking fumes compared with the levels the morning before (P-value = 0.004). There was also a trend of an increase in interleukin (IL)-6 in blood, ethane in exhaled air, and IL-1β in EBC after exposure to cooking fumes. In a sub-analysis of 12 subjects, there was also an increase in the levels of ethane—from 2.83 parts per billion (ppb) on the morning before exposure to cooking fumes to 3.53 ppb on the morning after exposure (P = 0.013)—and IL-1β—from 1.04 on the morning before exposure to cooking fumes to 1.39 pg ml–1 immediately after (P = 0.024). Conclusion: In our experimental setting, we were able to unveil only small changes in the levels of inflammatory markers in exhaled air and in blood after short-term exposure to moderate concentrations of cooking fumes. PMID:23179989
40 CFR 60.2260 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2014 CFR
2014-07-01
... SOURCES Standards of Performance for Commercial and Industrial Solid Waste Incineration Units Air Curtain... paper copy or electronic format, unless the Administrator approves another format, for at least 5 years...) Submit initial and annual opacity test reports as electronic or paper copy on or before the applicable...
40 CFR 60.2260 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2013 CFR
2013-07-01
... SOURCES Standards of Performance for Commercial and Industrial Solid Waste Incineration Units Air Curtain... paper copy or electronic format, unless the Administrator approves another format, for at least 5 years...) Submit initial and annual opacity test reports as electronic or paper copy on or before the applicable...
40 CFR 60.3062 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Other Solid Waste Incineration Units That Commenced Construction On or Before December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3062 What is... this subpart. (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent yard waste. (4...
40 CFR 60.2810 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30... “Air Curtain Incinerators” (§§ 60.2810 through 60.2870). (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent mixture of only wood waste, clean lumber, and/or yard waste. ...
40 CFR 60.3062 - What is an air curtain incinerator?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Other Solid Waste Incineration Units That Commenced Construction On or Before December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3062 What is... this subpart. (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent yard waste. (4...
40 CFR 60.3062 - What is an air curtain incinerator?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Other Solid Waste Incineration Units That Commenced Construction On or Before December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3062 What is... this subpart. (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent yard waste. (4...
40 CFR 60.3062 - What is an air curtain incinerator?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Other Solid Waste Incineration Units That Commenced Construction On or Before December 9, 2004 Model Rule-Air Curtain Incinerators That Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3062 What is... this subpart. (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent yard waste. (4...
77 FR 48492 - Event Data Recorders
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-14
... that [cir] Involve side or side curtain/tube air bags such that EDR data would only need to be locked... deployable restraints other than frontal, side or side/curtain air bags such that EDR data would not need to.... The final rule was intended to be technology-neutral, so as to permit compliance with any available...
Kolb, Gregory J [Albuquerque, NM
2012-02-07
A suction-recirculation device for stabilizing the flow of a curtain of blackened heat absorption particles falling inside of a solar receiver with an open aperture. The curtain of particles absorbs the concentrated heat from a solar mirror array reflected up to the receiver on a solar power tower. External winds entering the receiver at an oblique angle can destabilize the particle curtain and eject particles. A fan and ductwork is located behind the back wall of the receiver and sucks air out through an array of small holes in the back wall. Any entrained particles are separated out by a conventional cyclone device. Then, the air is recirculated back to the top of the receiver by injecting the recycled air through an array of small holes in the receiver's ceiling and upper aperture front wall. Since internal air is recirculated, heat losses are minimized and high receiver efficiency is maintained. Suction-recirculation velocities in the range of 1-5 m/s are sufficient to stabilize the particle curtain against external wind speeds in excess of 10 m/s.
40 CFR 61.172 - Standard for new and existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... operation. (ii) The back of the hood enclosure shall be fully enclosed and sealed against the primary hood...-slotted plenum shall be connected to a fan. When activated, the fan shall push air through the horizontal... hood enclosure, side- and back-wall hood seals, and the horizontal slot. (ii) Replace or repair any...
Characteristics of PAHs from deep-frying and frying cooking fumes.
Yao, Zhiliang; Li, Jing; Wu, Bobo; Hao, Xuewei; Yin, Yong; Jiang, Xi
2015-10-01
Cooking fumes are an important indoor source of polycyclic aromatic hydrocarbons (PAHs). Because indoor pollution has a more substantial impact on human health than outdoor pollution, PAHs from cooking fumes have drawn considerable attention. In this study, 16 PAHs emitted through deep-frying and frying methods using rapeseed, soybean, peanut, and olive oil were examined under a laboratory fume hood. Controlled experiments were conducted to collect gas- and particulate-phase PAHs emitted from the cooking oil fumes, and PAH concentrations were quantified via high-performance liquid chromatography (HPLC). The results show that deep-frying methods generate more PAHs and benzo[a]pyrene (B[a]P) (1.3 and 10.9 times, respectively) because they consume greater volumes of edible oil and involve higher oil temperatures relative to those of frying methods. In addition, the total B[a]Peq concentration of deep-frying is 2.2-fold larger than that of frying. Regarding the four types of edible oils studied, rapeseed oil produced more PAH emission than the other three oil varieties. For all of the cooking tests, three- and four-ringed PAHs were the main PAH components regardless of the food and oil used. Concerning the PAH partition between gas and particulate phase, the gaseous compounds accounted for 59-96 % of the total. Meanwhile, the particulate fraction was richer of high molecular weight PAHs (five-six rings). Deep-frying and frying were confirmed as important sources of PAH pollution in internal environments. The results of this study provide additional insights into the polluting features of PAHs produced via cooking activities in indoor environments.
40 CFR 62.14805 - What must I do if I close my air curtain incinerator and then restart it?
Code of Federal Regulations, 2011 CFR
2011-07-01
... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14805 What must I do if I close my...
40 CFR 62.14805 - What must I do if I close my air curtain incinerator and then restart it?
Code of Federal Regulations, 2012 CFR
2012-07-01
... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14805 What must I do if I close my...
40 CFR 62.14805 - What must I do if I close my air curtain incinerator and then restart it?
Code of Federal Regulations, 2014 CFR
2014-07-01
... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14805 What must I do if I close my...
40 CFR 62.14805 - What must I do if I close my air curtain incinerator and then restart it?
Code of Federal Regulations, 2013 CFR
2013-07-01
... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14805 What must I do if I close my...
2000-08-01
ERDC/SL ; TR-00-4) Includes bibliographic references. 1. Underwater explosions - Testing. 2. Shock waves. 3. Air curtains. 4. Wilmington, (N.C...water is the placement of air curtains or bubble screens around the underwater explosive source. Bubble screens are generated by pumping air into a...Geomechanics and Explosion Effects Division (GEED), Structures Laboratory (SL), Waterways Experiment Station (WES), U. S. Army Engineer Research and
2015-08-10
stainless steel foil substrates that were 50 microns thick. The coatings were then placed in an oven at 60oC for 24 hours to evaporate the solvent. After...drying, the coatings were cooled at room temperature in a fume hood for 24 hours. The free standing film is photographed in Figure 2. The film was cut...composition were examined and flame speeds were measured. A glass slide with the sample strip attached was placed on a steel block housed in a
Code of Federal Regulations, 2012 CFR
2012-07-01
... incinerator burns only wood waste, clean lumber, and yard waste? 60.3063 Section 60.3063 Protection of... Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3063 When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard waste? Table 1 of this subpart specifies the final...
Code of Federal Regulations, 2014 CFR
2014-07-01
... incinerator burns only wood waste, clean lumber, and yard waste? 60.3063 Section 60.3063 Protection of... Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3063 When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard waste? Table 1 of this subpart specifies the final...
Code of Federal Regulations, 2013 CFR
2013-07-01
... incinerator burns only wood waste, clean lumber, and yard waste? 60.3063 Section 60.3063 Protection of... Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3063 When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard waste? Table 1 of this subpart specifies the final...
Code of Federal Regulations, 2010 CFR
2010-07-01
... incinerator burns only wood waste, clean lumber, and yard waste? 60.3063 Section 60.3063 Protection of... Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3063 When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard waste? Table 1 of this subpart specifies the final...
Code of Federal Regulations, 2011 CFR
2011-07-01
... incinerator burns only wood waste, clean lumber, and yard waste? 60.3063 Section 60.3063 Protection of... Burn Only Wood Waste, Clean Lumber, and Yard Waste § 60.3063 When must I comply if my air curtain incinerator burns only wood waste, clean lumber, and yard waste? Table 1 of this subpart specifies the final...
Schumacher, Jan; Gray, Stuart A; Michel, Sophie; Alcock, Roger; Brinker, Andrea
2013-02-01
Emergency pediatric life support (EPLS) of children infected with transmissible respiratory diseases requires adequate respiratory protection for medical first responders. Conventional air-purifying respirators (APR) and modern loose-fitting powered air-purifying respirator-hoods (PAPR-hood) may have a different impact during pediatric resuscitation and therefore require evaluation. This study investigated the influence of APRs and PAPR-hoods during simulated pediatric cardiopulmonary resuscitation. Study design was a randomized, controlled, crossover study. Sixteen paramedics carried out a standardized EPLS scenario inside an ambulance, either unprotected (control) or wearing a conventional APR or a PAPR-hood. Treatment times and wearer comfort were determined and compared. All paramedics completed the treatment objectives of the study arms without adverse events. Study subjects reported that communication, dexterity and mobility were significantly better in the APR group, whereas the heat-build-up was significantly less in the PAPR-hood group. Treatment times compared to the control group did not significantly differ for the APR group but did with the PAPR-hood group (261±12 seconds for the controls, 275±9 seconds for the conventional APR and 286±13 seconds for the PAPR-hood group, P < .05. APRs showed a trend to better treatment times compared to PAPR-hoods during simulated pediatric cardiopulmonary resuscitation. Study participants rated mobility, ease of communication and dexterity with the tight-fitting APR system significantly better compared to the loose-fitting PAPR-hood.
Antonini, James M; Roberts, Jenny R; Stone, Samuel; Chen, Bean T; Schwegler-Berry, Diane; Chapman, Rebecca; Zeidler-Erdely, Patti C; Andrews, Ronnee N; Frazer, David G
2011-05-01
Welding generates complex metal fumes that vary in composition. The objectives of this study were to compare the persistence of deposited metals and the inflammatory potential of stainless and mild steel welding fumes, the two most common fumes used in US industry. Sprague-Dawley rats were exposed to 40 mg/m(3) of stainless or mild steel welding fumes for 3 h/day for 3 days. Controls were exposed to filtered air. Generated fume was collected, and particle size and elemental composition were determined. Bronchoalveolar lavage was done on days 0, 8, 21, and 42 after the last exposure to assess lung injury/inflammation and to recover lung phagocytes. Non-lavaged lung samples were analyzed for total and specific metal content as a measure of metal persistence. Both welding fumes were similar in particle morphology and size. Following was the chemical composition of the fumes-stainless steel: 57% Fe, 20% Cr, 14% Mn, and 9% Ni; mild steel: 83% Fe and 15% Mn. There was no effect of the mild steel fume on lung injury/inflammation at any time point compared to air control. Lung injury and inflammation were significantly elevated at 8 and 21 days after exposure to the stainless steel fume compared to control. Stainless steel fume exposure was associated with greater recovery of welding fume-laden macrophages from the lungs at all time points compared with the mild steel fume. A higher concentration of total metal was observed in the lungs of the stainless steel welding fume at all time points compared with the mild steel fume. The specific metals present in the two fumes were cleared from the lungs at different rates. The potentially more toxic metals (e.g., Mn, Cr) present in the stainless steel fume were cleared from the lungs more quickly than Fe, likely increasing their translocation from the respiratory system to other organs.
133Xe contamination found in internal bacteria filter of xenon ventilation system.
Hackett, Michael T; Collins, Judith A; Wierzbinski, Rebecca S
2003-09-01
We report on (133)Xe contamination found in the reusable internal bacteria filter of our xenon ventilation system. Internal bacteria filters (n = 6) were evaluated after approximately 1 mo of normal use. The ventilation system was evacuated twice to eliminate (133)Xe in the system before removal of the filter. Upon removal, the filter was monitored using a survey meter with an energy-compensated probe and was imaged on a scintillation camera. The filter was monitored and imaged over several days and was stored in a fume hood. Estimated (133)Xe activity in each filter immediately after removal ranged from 132 to 2,035 kBq (3.6-55.0 micro Ci), based on imaging. Initial surface radiation levels ranged from 0.4 to 4.5 micro Sv/h (0.04-0.45 mrem/h). The (133)Xe activity did not readily leave the filter over time (i.e., time to reach half the counts of the initial decay-corrected image ranged from <6 to >72 h). The majority of the image counts (approximately 70%) were seen in 2 distinctive areas in the filter. They corresponded to sites where the manufacturer used polyurethane adhesive to attach the fiberglass filter medium to the filter housing. (133)Xe contamination within the reusable internal bacteria filter of our ventilation system was easily detected by a survey meter and imaging. Although initial activities and surface radiation levels were low, radiation safety practices would dictate that a (133)Xe-contaminated bacteria filter be stored preferably in a fume hood until it cannot be distinguished from background before autoclaving or disposal.
Noise reduction by the application of an air-bubble curtain in offshore pile driving
NASA Astrophysics Data System (ADS)
Tsouvalas, A.; Metrikine, A. V.
2016-06-01
Underwater noise pollution is a by-product of marine industrial operations. In particular, the noise generated when a foundation pile is driven into the soil with an impact hammer is considered to be harmful for the aquatic species. In an attempt to reduce the ecological footprint, several noise mitigation techniques have been investigated. Among the various solutions proposed, the air-bubble curtain is often applied due to its efficacy in noise reduction. In this paper, a model is proposed for the investigation of the sound reduction during marine piling when an air-bubble curtain is placed around the pile. The model consists of the pile, the surrounding water and soil media, and the air-bubble curtain which is positioned at a certain distance from the pile surface. The solution approach is semi-analytical and is based on the dynamic sub-structuring technique and the modal decomposition method. Two main results of the paper can be distinguished. First, a new model is proposed that can be used for predictions of the noise levels in a computationally efficient manner. Second, an analysis is presented of the principal mechanisms that are responsible for the noise reduction due to the application of the air-bubble curtain in marine piling. The understanding of these mechanisms turns to be crucial for the exploitation of the maximum efficiency of the system. It is shown that the principal mechanism of noise reduction depends strongly on the frequency content of the radiated sound and the characteristics of the bubbly medium. For piles of large diameter which radiate most of the acoustic energy at relatively low frequencies, the noise reduction is mainly attributed to the mismatch of the acoustic impedances between the seawater and the bubbly layer. On the contrary, for smaller piles and when the radiated acoustic energy is concentrated at frequencies close to, or higher than, the resonance frequency of the air bubbles, the sound absorption within the bubbly layer becomes critical.
Three-Dimensional Air Curtains
NASA Technical Reports Server (NTRS)
Stephenson, J. G.; Daniher, C. E. J.
1982-01-01
Proposed scheme for gas "curtains" partitions large volume into several separate spaces. Concept may also be useful in such terrestrial applications as unobtrusive isolation of smoking and nonsmoking sections in restaurants and office. Scheme is suitable for isolation of objectionable or hazardous gases in free space.
Contractor cuts solar gain with custom window curtain
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ingraham, R.
1985-04-22
A local energy services contractor, using a 210-foot motorized thermal curtain to deflect sunlight entering the windows, has reduced excessive heat gain at a racetrack clubhouse here, cutting air conditioning run-time by about 75%. Because Mobile Greyhound Park's clubhouse faces east, direct exposure to sunlight from dawn to afternoon race time, about 1 p.m., was bringing the indoor temperature to almost 100/sup 0/, according to Stan Norris, operations management for the contracting firm, Technical Energy Controls, Inc. Lowering the temperature to a comfortable level required running four Carrier Corporation air handling units, rated at a total of more than 170more » tons, for about eight hours, and annual energy bills were running at about $240,000, Norris said. With the aluminum foil-backed vinyl curtain, the air handling units need only operate two hours to bring temperatures to comfort levels.« less
Synthetic Reference Materials Based on Polymer Films for the Control of Welding Fumes Composition
NASA Astrophysics Data System (ADS)
Kuznetsova, O. V.; Kuznetsova, A. N.; Begunova, L. A.
2017-04-01
Analysis of the current hygienic situation in the welding production showed that the intensification of welding processes involves the deterioration of air quality, which negatively affects the welders health. Welders are exposed to a variety of metal fumes, including manganese that may elevate the risk for neurological diseases. The control of metals concentration in the air of the working area is difficult due to the lack of reference materials. The creation of reference materials of welding fumes composition is a challenge due to chemical characteristics of their physical properties. Synthetic samples in a form of the polymer film containing powder particles of welding fumes were create. Studies on the selection of the polymer were done. Experiments proved that the qualitative materials of synthetic welding fumes are obtained by using polyvinyl alcohol. The metals concentration in the samples was determined by X-ray fluorescence analysis. The obtained data demonstrates indirectly the uniform distribution of welding fumes powder particles on the polymer film.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Half-mask facepieces, full facepieces, hoods, and... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.135 Half-mask facepieces, full facepieces, hoods, and helmets; fit; minimum requirements. (a) Half-mask facepieces and full facepieces shall...
42 CFR 84.1139 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 1 2011-10-01 2011-10-01 false Air velocity and noise levels; hoods and helmets; minimum requirements. 84.1139 Section 84.1139 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1139 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 42 Public Health 1 2013-10-01 2013-10-01 false Air velocity and noise levels; hoods and helmets; minimum requirements. 84.1139 Section 84.1139 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1139 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 42 Public Health 1 2014-10-01 2014-10-01 false Air velocity and noise levels; hoods and helmets; minimum requirements. 84.1139 Section 84.1139 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1139 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 42 Public Health 1 2012-10-01 2012-10-01 false Air velocity and noise levels; hoods and helmets; minimum requirements. 84.1139 Section 84.1139 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1139 - Air velocity and noise levels; hoods and helmets; minimum requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Air velocity and noise levels; hoods and helmets; minimum requirements. 84.1139 Section 84.1139 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
[Evaluation of measurement uncertainty of welding fume in welding workplace of a shipyard].
Ren, Jie; Wang, Yanrang
2015-12-01
To evaluate the measurement uncertainty of welding fume in the air of the welding workplace of a shipyard, and to provide quality assurance for measurement. According to GBZ/T 192.1-2007 "Determination of dust in the air of workplace-Part 1: Total dust concentration" and JJF 1059-1999 "Evaluation and expression of measurement uncertainty", the uncertainty for determination of welding fume was evaluated and the measurement results were completely described. The concentration of welding fume was 3.3 mg/m(3), and the expanded uncertainty was 0.24 mg/m(3). The repeatability for determination of dust concentration introduced an uncertainty of 1.9%, the measurement using electronic balance introduced a standard uncertainty of 0.3%, and the measurement of sample quality introduced a standard uncertainty of 3.2%. During the determination of welding fume, the standard uncertainty introduced by the measurement of sample quality is the dominant uncertainty. In the process of sampling and measurement, quality control should be focused on the collection efficiency of dust, air humidity, sample volume, and measuring instruments.
40 CFR 467.02 - General definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... includes air pollution control scrubbers which are sometimes used to control fumes from chemical solution... cool. (s) Wet scrubbers are air pollution control devices used to remove particulates and fumes from... every plant in a subcategory, but when present is an integral part of the aluminum forming process. (c...
40 CFR 467.02 - General definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... includes air pollution control scrubbers which are sometimes used to control fumes from chemical solution... cool. (s) Wet scrubbers are air pollution control devices used to remove particulates and fumes from... every plant in a subcategory, but when present is an integral part of the aluminum forming process. (c...
40 CFR 467.02 - General definitions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... includes air pollution control scrubbers which are sometimes used to control fumes from chemical solution... cool. (s) Wet scrubbers are air pollution control devices used to remove particulates and fumes from... every plant in a subcategory, but when present is an integral part of the aluminum forming process. (c...
Kastberger, Gerald; Waddoup, Dominique; Weihmann, Frank; Hoetzl, Thomas
2016-01-01
The Asian giant honeybees (Apis dorsata) build single-comb nests in the open, which makes this species particularly susceptible to environmental strains. Long-term infrared (IR) records documented cool nest regions (CNR) at the bee curtain (nCNR = 207, nnests > 20) distinguished by marked negative gradients (ΔTCNR/d < -3°C / 5 cm) at their margins. CNRs develop and recede within minutes, predominantly at higher ambient temperatures in the early afternoon. The differential size (ΔACNR) and temperature (ΔTCNR) values per time unit correlated mostly positively (RAT > 0) displaying the Venturi effect, which evidences funnel properties of CNRs. The air flows inwards through CNRs, which is verified by the negative spatial gradient ΔTCNR/d, by the positive grading of TCNR with Tamb and lastly by fanners which have directed their abdomens towards CNRs. Rare cases of RAT < 0 (< 3%) document closing processes (for ΔACNR/Δt < -0.4 cm2/s) but also suggest ventilation of the bee curtain (for ΔACNR/Δt > +0.4 cm2/s) displaying "inhalation" and "exhalation" cycling. "Inhalation" could be boosted by bees at the inner curtain layers, which stretch their extremities against the comb enlarging the inner nest lumen and thus causing a pressure fall which drives ambient air inwards through CNR funnels. The relaxing of the formerly "activated" bees could then trigger the "exhalation" process, which brings the bee curtain, passively by gravity, close to the comb again. That way, warm, CO2-enriched nest-borne air is pressed outwards through the leaking mesh of the bee curtain. This ventilation hypothesis is supported by IR imaging and laser vibrometry depicting CNRs in at least four aspects as low-resistance convection funnels for maintaining thermoregulation and restoring fresh air in the nest.
Wang, Hao; Cheng, Weimin; Sun, Biao; Yu, Haiming; Jin, Hu
2018-03-01
To understand the impacts of the axial-to-radial airflow quantity ratio (denoted as R) and the suction distance (denoted as D s ) on air curtain dust control in a fully mechanized coal face, the 3 down 610 coal face in Jiangzhuang coal mine was numerically simulated in this study. A mathematic model was established to describe the airflow migration and dust diffusion in a coal face, and a scaled physical model was constructed. The comparison between simulation results and field measurements validated the model and the parameter settings. Furthermore, the airflow migration and dust diffusion at various R and D s are analyzed using Ansys CFD. The results show that a reduction of R and D s is conducive to the formation of an effective axial dust control air curtain; the dust diffusion distance decreases with the decrease of both R and D s . By analyzing the simulation results, the optimal parameter for air curtain dust control in the 3 down 610 coal face and those faces with similar production conditions is determined as R = 1/9 and D s = 2 m. Under the optimal parameter condition, the high-concentration dust can be confined in front of the mining driver within a space 5.8 m away from the coal face.
Year-round Application of Water Curtain for Environmental Control in Greenhouse
NASA Astrophysics Data System (ADS)
Ibuki, R.; Sugita, E.
2011-12-01
In large area of Japan needs forced environmental control to cultivate yields in hard temperature condition. Water Curtain is applied in Japan for night time air temperature control of small greenhouse, making strawberry and covered by plastic film. Water is splayed on extended plastic film, located above strawberry and below roof film. Underground water is utilized for cooling in summer, and warming in winter. Heat exchange between water and ground, and also water and air in the greenhouse is occurring in this system. Furthermore, heat transfer by radiation effect is also controlled by water membrane. In winter night, infrared radiation through plastic film is reduced by water membrane because of its high absorption coefficient on wave length of infrared. Besides water has a high transparency on wave length of visible light. These features are useful on the daytime radiation control of greenhouse to maintain visible light level for photosynthesis and to reduce excess infrared, damages yields in summer. Also in daytime of sunny day in winter season, temperature is too high to cultivate yields in closed greenhouse. Under this situation, water curtain is useful to storage from broad area in greenhouse excess heat from air in the circulation water. Warm water is useful to maintain temperature in greenhouse. On the contrary, in summer season, water can storage heat in daytime and release in night time. Water curtain system will contribute to be a sustainable and low energy consumption system to maintain comfortable environment for yields growth. For this reason we are considering to use water curtain in year-round. At the first step of the year-round application, day time use in summer is experimentally investigated. General water curtain splays water on plastic film extended on metal pipe. In this situation water is gathered at valley part of the film. Then water membrane is partially made and radiation control is not effective at large area. Therefore we applied new covering way to realize higher water covering ratio. With this way selective reduction effect of water curtain, which reduce infrared more than visible light is quantitatively measured. Also small greenhouse to growth plants under it is settled to measure thermal net, heat absorption, water and air temperature variation and yields growth. From measurements way of making water membrane influenced water temperature elevation.
Speciation of hexavalent chromium in welding fumes interference by air oxidation of chromium.
Zatka, V J
1985-06-01
The determination of various chromium species in welding fume normally involves digestion in a hot alkaline solution. This work confirms that Cr(III) can be oxidized to Cr(VI) during this digestion. However, only dissolved forms of Cr(III), such as the hydroxochromate(III) ion, [Cr(OH)4], are susceptible to oxidation under these conditions. The air oxidation of Cr(III) can be prevented by hydrolytic destabilization of the hydroxochromate(III) complex by the presence of magnesium hydroxide precipitate. The procedure has been used successfully in the determination of insoluble chromium(VI) in welding fumes. Excellent reproducibility is documented for soluble and insoluble chromium(VI) fractions in the analysis of a bulk sample of welding fume.
Forensic aspects of the aerotoxic syndrome.
Abeyratne, Ruwantissa
2002-01-01
Three decades ago, cabin air quality was seemingly not an issue in commercial aviation and the incidence of disease through air borne vectors or toxic fumes was uncommon among passengers and crew. However, it is claimed that modern day jet airliners generally carry the threat of disease through the ventilator systems of these aircraft which are designed for optimum efficiency, leaving them exposed to lapses in the recycling of clean air and blocking fumes from engine exhausts of the jets from entering the inhabited parts of the aircraft. It has been claimed that aerotoxic fumes are most common in the cockpit, and that the technical crew are the most susceptible to the aerotoxic syndrome.
Bacteriological evaluation of a down-draught necropsy table ventilation system.
al-Wali, W; Kibbler, C C; McLaughlin, J E
1993-08-01
To evaluate the microbiological efficacy of a down-draught necropsy table ventilation system (which surrounds the cadaver with a "curtain" of air under continuous extraction) during post mortem procedures. Air sampling was carried out both in the presence and absence of staff and cadaver and during a full post mortem procedure, with functioning and non-functioning table air extraction. The penetration of the air "curtain" was also examined during the use of an oscillating bone saw by means of a tracer organism, Bacillus subtilis var niger, painted on to the skull. There was little difference between bacterial counts obtained in the presence of staff only, staff plus cadaver, or during a post mortem examination. With all counts obtained, however, there was a two to three-fold reduction when the ventilation was in operation compared with when the extract duct was occluded. Using the tracer organism, a two to three log reduction in counts was shown when the "curtain" was in operation during the use of the oscillating bone saw. These results suggest that the system provides potential protection for post mortem room staff against airborne infections.
42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 42 Public Health 1 2013-10-01 2013-10-01 false Dust, fume, and mist air-purifying filter tests; performance requirements; general. 84.1143 Section 84.1143 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 42 Public Health 1 2014-10-01 2014-10-01 false Dust, fume, and mist air-purifying filter tests; performance requirements; general. 84.1143 Section 84.1143 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Dust, fume, and mist air-purifying filter tests; performance requirements; general. 84.1143 Section 84.1143 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 1 2011-10-01 2011-10-01 false Dust, fume, and mist air-purifying filter tests; performance requirements; general. 84.1143 Section 84.1143 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
42 CFR 84.1143 - Dust, fume, and mist air-purifying filter tests; performance requirements; general.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 42 Public Health 1 2012-10-01 2012-10-01 false Dust, fume, and mist air-purifying filter tests; performance requirements; general. 84.1143 Section 84.1143 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...
Smith, L A; Thomson, S J
2003-01-01
A research summary is presented that emphasizes ARS achievements in application technology over the past 2-3 years. Research focused on the improvement of agricultural pesticide application is important from the standpoint of crop protection as well as environmental safety. Application technology research is being actively pursued within the ARS, with a primary focus on application system development, drift management, efficacy enhancement and remote sensing. Research on application systems has included sensor-controlled hooded sprayers, new approaches to direct chemical injection, and aerial electrostatic sprayers. For aerial application, great improvements in on-board flow controllers permit accurate field application of chemicals. Aircraft parameters such as boom position and spray release height are being altered to determine their effect on drift. Other drift management research has focused on testing of low-drift nozzles, evaluation of pulsed spray technologies and evaluation of drift control adjuvants. Research on the use of air curtain sprayers in orchards, air-assist sprayers for row crops and vegetables, and air deflectors on aircraft has documented improvements in application efficacy. Research has shown that the fate of applied chemicals is influenced by soil properties, and this has implications for herbicide efficacy and dissipation in the environment. Remote sensing systems are being used to target areas in the field where pests are present so that spray can be directed to only those areas. Soil and crop conditions influence propensity for weeds and insects to proliferate in any given field area. Research has indicated distinct field patterns favorable for weed growth and insect concentration, which can provide further assistance for targeted spraying.
Driver's side curtain air bag-related globe rupture.
Porter, Ashley J; Hayes, Rylan; Lee, Lawrence; O'Hagan, Stephen
2018-06-04
A 35-year-old man presented after a high-speed motor vehicle accident and the driver's side curtain air bag causing blunt force trauma rupturing his right globe. The tangential force of the air bag resulted in an unusual arcuate horseshoe-shaped rupture through the lateral rectus insertion, causing avulsion of the muscle and tearing the sclera, with the apices of the tear extending anteriorly towards the limbus. Repair of the globe rupture was undertaken, and secondary vitrectomy revealed that the scleral tear had not involved the retina abutting the ora serrata. Silicone oil tamponade was used to fill the globe and the postoperative best corrected vision was 6/9. This is the first reported case of a ruptured globe caused by a side curtain air bag, resulting in a uniquely shaped arcuate scleral wound combined with lateral rectus avulsion, not associated with rhegmatogenous retinal damage, and is the first air bag-related globe rupture with scleral involvement to report a final best-corrected visual acuity better than 6/60. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Influence of surfactant upon air entrainment hysteresis in curtain coating
NASA Astrophysics Data System (ADS)
Marston, J. O.; Hawkins, V.; Decent, S. P.; Simmons, M. J. H.
2009-03-01
The onset of air entrainment for curtain coating onto a pre-wetted substrate was studied experimentally in similar parameter regimes to commercial coating ( Re = ρ Q/μ = O(1), We = ρ Q u c /σ = O(10), Ca = μ U/σ = O(1)). Impingement speed and viscosity were previously shown to be critical parameters in correlating air entrainment data with three qualitatively different regimes of hydrodynamic assist identified (Marston et al. in Exp Fluids 42(3):483-488, 2007a). The interaction of the impinging curtain with the pre-existing film also led to a significant hysteretic effect throughout the flow rate-substrate speed parameter space. For the first time, results considering the influence of surfactants are presented in attempt to elucidate the relative importance of surface tension in this inertia-dominated system. The results show quantitative and qualitative differences to previous results with much more complex hysteretic behaviour which has only been reported previously for rough surfaces.
... small-particle or high-efficiency particulate air (HEPA) filter. Shampoo the carpet frequently. Curtains and blinds. Use ... dander they shed. Air filtration. Choose an air filter that has a small-particle or HEPA filter. ...
Fume Cupboards in Schools. (Revision of Design Note 29). Building Bulletin 88.
ERIC Educational Resources Information Center
Tawney, David
Regulations require hazardous gases in school science classrooms to be controlled, i.e., their levels in the air kept below the exposure limits, with fume cupboards being the most usual method. This document reviews the requirements for fume cupboards used in schools and colleges for teaching the sciences, mainly chemistry and biology, up to…
NASA Astrophysics Data System (ADS)
Prata, Ademir A.; Lucernoni, Federico; Santos, Jane M.; Capelli, Laura; Sironi, Selena; Le-Minh, Nhat; Stuetz, Richard M.
2018-04-01
This study assesses the mass transfer of compounds inside the US EPA flux hood, one of the enclosure devices most commonly employed for the direct measurement of atmospheric emissions from liquid surfaces in wastewater treatment plants (WWTPs). Experiments comprised the evaporation of water and the volatilisation of a range of volatile organic compounds (VOCs). Special attention was given to the evaluation of the mass transfer coefficients in the microenvironment created by the flux hood and the effects of concentration build up in the hood's headspace. The VOCs emission rates and the water evaporation rates generally increased with the sweep air flow rate, as did the mass transfer coefficients for all compounds. The emission of compounds whose volatilisation is significantly influenced by the gas phase was greatly affected by concentration build up, whereas this effect was not significant for liquid phase-controlled compounds. The gas-film mass transfer coefficient (kG) estimated inside the US EPA flux hood was of the same order as the respective kG reported in the literature for wind tunnel-type devices, but the emission rates measured by the flux hood can be expected to be lower, due to the concentration build-up. Compared against an emission model for the passive surfaces in WWTPs, the mass transfer of acetic acid (representing a gas phase-dominated compound) inside the US EPA flux hood was equivalent to conditions of wind speeds at 10 m height (U10) of 0.27, 0.51 and 0.99 m s-1, respectively, for sweep air flow rates of 2, 5 and 10 L min-1. On the other hand, for higher wind speeds, the emission rates of gas phase-controlled compounds obtained with the flux hood can be considerably underestimated: for instance, at U10 = 5 m s-1, the emission rates of acetic acid inside the flux hood would be approximately 23, 12 and 6 times lower than the emission rates in the field, for sweep air flow rates of 2, 5 and 10 L min-1, respectively. A procedure is presented in order to scale the emission rates of these compounds measured with the flux hood to field conditions of higher winds.
Lao, Jia-Yong; Wu, Chen-Chou; Bao, Lian-Jun; Liu, Liang-Ying; Shi, Lei; Zeng, Eddy Y
2018-10-15
Barbecue (BBQ) is one of the most popular cooking activities with charcoal worldwide and produces abundant polycyclic aromatic hydrocarbons (PAHs) and particulate matter. Size distribution and clothing-air partitioning of particle-bound PAHs are significant for assessing potential health hazards to humans due to exposure to BBQ fumes, but have not been examined adequately. To address this issue, particle and gaseous samples were collected at 2-m and 10-m distances from a cluster of four BBQ stoves. Personal samplers and cotton clothes were carried by volunteers sitting near the BBQ stoves. Particle-bound PAHs (especially 4-6 rings) derived from BBQ fumes were mostly affiliated with fine particles in the size range of 0.18-1.8 μm. High molecular-weight PAHs were mostly unimodal peaking in fine particles and consequently had small geometric mean diameters and standard deviations. Source diagnostics indicated that particle-bound PAHs in BBQ fumes were generated primarily by combustion of charcoal, fat content in food, and oil. The influences of BBQ fumes on the occurrence of particle-bound PAHs decreased with increasing distance from BBQ stoves, due to increased impacts of ambient sources, especially by petrogenic sources and to a lesser extent by wind speed and direction. Octanol-air and clothing-air partition coefficients of PAHs obtained from personal air samples were significantly correlated to each other. High molecular-weight PAHs had higher area-normalized clothing-air partition coefficients in cotton clothes, i.e., cotton fabrics may be a significant reservoir of higher molecular-weight PAHs. Particle-bound PAHs from barbecue fumes are generated largely from charcoal combustion and food-charred emissions and mainly affiliated with fine particles. Copyright © 2018. Published by Elsevier B.V.
40 CFR 60.2860 - What are the emission limitations for air curtain incinerators?
Code of Federal Regulations, 2014 CFR
2014-07-01
... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model Rule-Air...
40 CFR 60.2865 - How must I monitor opacity for air curtain incinerators?
Code of Federal Regulations, 2014 CFR
2014-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model Rule-Air...
Kastberger, Gerald; Waddoup, Dominique; Weihmann, Frank; Hoetzl, Thomas
2016-01-01
The Asian giant honeybees (Apis dorsata) build single-comb nests in the open, which makes this species particularly susceptible to environmental strains. Long-term infrared (IR) records documented cool nest regions (CNR) at the bee curtain (nCNR = 207, nnests > 20) distinguished by marked negative gradients (ΔTCNR/d < -3°C / 5 cm) at their margins. CNRs develop and recede within minutes, predominantly at higher ambient temperatures in the early afternoon. The differential size (ΔACNR) and temperature (ΔTCNR) values per time unit correlated mostly positively (RAT > 0) displaying the Venturi effect, which evidences funnel properties of CNRs. The air flows inwards through CNRs, which is verified by the negative spatial gradient ΔTCNR/d, by the positive grading of TCNR with Tamb and lastly by fanners which have directed their abdomens towards CNRs. Rare cases of RAT < 0 (< 3%) document closing processes (for ΔACNR/Δt < -0.4 cm2/s) but also suggest ventilation of the bee curtain (for ΔACNR/Δt > +0.4 cm2/s) displaying “inhalation” and “exhalation” cycling. “Inhalation” could be boosted by bees at the inner curtain layers, which stretch their extremities against the comb enlarging the inner nest lumen and thus causing a pressure fall which drives ambient air inwards through CNR funnels. The relaxing of the formerly “activated” bees could then trigger the “exhalation” process, which brings the bee curtain, passively by gravity, close to the comb again. That way, warm, CO2-enriched nest-borne air is pressed outwards through the leaking mesh of the bee curtain. This ventilation hypothesis is supported by IR imaging and laser vibrometry depicting CNRs in at least four aspects as low-resistance convection funnels for maintaining thermoregulation and restoring fresh air in the nest. PMID:27487188
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heitbrink, W.A.; Cooper, T.C.; Edmonds, M.A.
1992-03-01
A study was made to evaluate and document the effectiveness of a metal inert gas (MIG) welder with built in ventilation to control potentially hazardous conditions at Church Brother's Collision Repair (SIC-7531), Greenwood, Indiana. Air contaminant exposures were measured during a 1 hour repair job while using a ventilated MIG welder and while using a conventional MIG welder. The ventilation system of the MIG did reduce worker exposure to welding fumes. However, the sampling was done on a single repair job, thus limiting the conclusions which can be drawn from the study. Some welding fumes were not captured by themore » ventilated welder, suggesting that the MIG with ventilation provided incomplete control of the generated fumes. In some cases the metal on the other side of the welding area became sufficiently hot to generate its own fumes. The car body itself appears to block the capture of these fumes by the ventilated MIG welder. When welding inside the car without the ventilated welder, the fumes generated were more concentrated than those generated by welding outside of the car under similar conditions. There is a decreased dilution of the fumes inside the car due to a lack of air movement. The authors conclude that while the control technique appeared to lessen exposure to welding fumes, additional investigation is needed to verify the data.« less
Bacteriological evaluation of a down-draught necropsy table ventilation system.
al-Wali, W; Kibbler, C C; McLaughlin, J E
1993-01-01
AIMS--To evaluate the microbiological efficacy of a down-draught necropsy table ventilation system (which surrounds the cadaver with a "curtain" of air under continuous extraction) during post mortem procedures. METHODS--Air sampling was carried out both in the presence and absence of staff and cadaver and during a full post mortem procedure, with functioning and non-functioning table air extraction. The penetration of the air "curtain" was also examined during the use of an oscillating bone saw by means of a tracer organism, Bacillus subtilis var niger, painted on to the skull. RESULTS--There was little difference between bacterial counts obtained in the presence of staff only, staff plus cadaver, or during a post mortem examination. With all counts obtained, however, there was a two to three-fold reduction when the ventilation was in operation compared with when the extract duct was occluded. Using the tracer organism, a two to three log reduction in counts was shown when the "curtain" was in operation during the use of the oscillating bone saw. CONCLUSIONS--These results suggest that the system provides potential protection for post mortem room staff against airborne infections. PMID:8408701
Respiratory symptoms of vendors in an open-air hawker center in brunei darussalam.
Nazurah Bt Abdul Wahid, Nurul Nor; Balalla, N B P; Koh, David
2014-01-01
We studied respiratory problems among vendors exposed to cooking fumes in an open-air hawker center. Exposure to cooking fumes from either the use of fossil fuels or liquefied petroleum gas (LPG) has been shown to be associated with adverse respiratory health effects. We conducted a cross-sectional study among 67 food vendors exposed to cooking fumes as well as 18 merchandise sellers at an open-air hawker center in Brunei Darussalam. Past medical and smoking history and exposure to cooking fumes were obtained. The validated American Thoracic Society Questionnaire with a translated Malay version was used to ask for respiratory symptoms. Compared to merchandise sellers (n = 18), cooking vendors (n = 67) had a higher self-reported respiratory symptoms (50.7% for those cooking and 33.3% for merchandise sellers). Cough (28.3%) was the main respiratory symptom experienced in cooking vendors and breathlessness (22.2%) among merchandise sellers. Half (50.0%) of cooking vendors who worked for more than 10 years had cough and 27.3% had phlegm. Those cooking with charcoal were two times more likely to have cough than those cooking with LPG. Cooking vendors with a job duration of more than 10 years were thrice more likely to have cough. Cooking vendors in the open-air hawker center exposed to cooking fumes had more respiratory symptoms compared to non-exposed merchandise sellers. The type of fuel used for cooking and duration of work was associated with increased prevalence of cough.
Ozone removal capability of a welding fume respirator containing activated charcoal.
Johnston, A R; Dyrud, J F; Shih, Y T
1989-09-01
Development of air purifying respirators for protection against ozone has been slowed by concerns about oxidation of charcoal and other available sorbents. The suitability of a charcoal sorbent for low concentrations of ozone was evaluated as a part of the development of a half-mask air purifying respirator designed for welding fumes and ozone. Testing of the respirator confirmed that charcoal can be a suitable sorbent for low levels of ozone. Where the respirator is properly selected, fit tested, and worn, respirator use against welding fumes and ozone at concentrations not exceeding 10 times the permissible exposure limit had been recommended.
Schindler, Birgit Karin; Weiss, Tobias; Schütze, Andre; Koslitz, Stephan; Broding, Horst Christoph; Bünger, Jürgen; Brüning, Thomas
2013-04-01
Aircraft cabin air can possibly be contaminated by tricresyl phosphates (TCP) from jet engine oils during fume events. o-TCP, a known neurotoxin, has been addressed to be an agent that might cause the symptoms reported by cabin crews after fume events. A total of 332 urine samples of pilots and cabin crew members in common passenger airplanes, who reported fume/odour during their last flight, were analysed for three isomers of tricresyl phosphate metabolites as well as dialkyl and diaryl phosphate metabolites of four flame retardants. None of the samples contained o-TCP metabolites above the limit of detection (LOD 0.5 μg/l). Only one sample contained metabolites of m- and p-tricresyl phosphates with levels near the LOD. Median metabolite levels of tributyl phosphate (TBP), tris-(2-chloroethyl) phosphate (TCEP) and triphenyl phosphate (TPP) (DBP 0.28 μg/l; BCEP 0.33 μg/l; DPP 1.1 μg/l) were found to be significantly higher than in unexposed persons from the general population. Median tris-(2-chloropropyl) phosphate (TCPP) metabolite levels were significantly not higher in air crews than in controls. Health complaints reported by air crews can hardly be addressed to o-TCP exposure in cabin air. Elevated metabolite levels for TBP, TCEP and TPP in air crews might occur due to traces of hydraulic fluid in cabin air (TBP, TPP) or due to release of commonly used flame retardants from the highly flame protected environment in the airplane. A slight occupational exposure of air crews to organophosphates was shown.
Hassani, Hamid; Golbabaei, Farideh; Ghahri, Asghar; Hosseini, Mostafa; Shirkhanloo, Hamid; Dinari, Behnam; Eskandari, Davood; Fallahi, Majid
2012-01-01
The objectives of this study were to evaluate manganese (Mn)-containing welding fumes' exposure, assess urinary Mn as a biomarker for Mn exposure and investigate the correlation of Mn in air, total fumes and urinary Mn with pulmonary function indices in 118 welders and 37 unexposed controls from two regions in Iran, Assaluyeh and Borujen. Air samples were collected on mixed cellulose ester membrane filters in personal air samplers and then analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES) (NIOSH Method 7300). For all participants, urine samples were collected during the entire work shift, and Mn in urine was determined by graphite furnace atomic absorption spectroscopy according to NIOSH Method 8310. Spirometric measurements were also done for participants. The maximum exposures to airborne Mn and total fumes were 0.304 ± 0.256 mg/m(3) and 21.52 ± 9.40 mg/m(3), respectively. The urine Mn levels in the various groups ranged between 0.77 to 7.58 μg/l. The correlation between airborne Mn and urinary Mn was significant for total whole participants. Some values of spirometric indices were statistically lower in welders rather than controls. Our results indicate that many welders have been exposed to higher concentrations of Mn-containing welding fumes. Urinary Mn can be used as a biomarker for Mn exposure. There were weak inverse correlations between Mn-containing welding fumes and pulmonary function indices, and the inverse correlation between urinary Mn with forced vital capacities (FVC) and forced expiratory volume in 1 s (FEV1) was significant.
13. VIEW OF A BBOX, WHICH WAS USED IN THE ...
13. VIEW OF A B-BOX, WHICH WAS USED IN THE FAST RECOVERY PROCESS. URANIUM OXIDE WAS TRANSFERRED FOR DISSOLUTION IN A ROOM WHICH HOUSED 3 ROWS OF B-BOXES. B-BOXES ARE CONTROLLED HOODS, SIMILAR TO LAB HOODS THAT OPERATED WITH HIGH AIR VELOCITIES AT THEIR OPENINGS TO ENSURE THAT THE VAPORS WERE CONTAINED WITHIN THE HOOD. (2/14/79) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO
Nitrous oxide as a tracer gas in the ASHRAE 110-1995 Standard.
Burke, Martin; Wong, Larry; Gonzales, Ben A; Knutson, Gerhard
2014-01-01
ANSI/ASHRAE Standard 110 provides a quantitative method for testing the performance of laboratory fume hoods. Through release of a known quantity (4.0 Lpm) of a tracer gas, and subsequent monitoring of the tracer gas concentration in the "breathing zone" of a mannequin positioned in front of the hood, this method allows for evaluation of laboratory hood performance. Standard 110 specifies sulfur hexafluoride (SF6) as the tracer gas; however, suitable alternatives are allowed. Through three series of performance tests, this analysis serves to investigate the use of nitrous oxide (N2O) as an alternate tracer gas for hood performance testing. Single gas tests were performed according to ASHRAE Standard 110-1995 with each tracer gas individually. These tests showed identical results using an acceptance criterion of AU 0.1 with the sash half open, nominal 18 inches (0.46m) high, and the face velocity at a nominal 60 fpm (0.3 m/s). Most data collected in these single gas tests, for both tracer gases, were below the minimum detection limit, thus two dual gas tests were developed for simultaneous sampling of both tracer gases. Dual gas dual ejector tests were performed with both tracer gases released simultaneously through two ejectors, and the concentration measured with two detectors using a common sampling probe. Dual gas single ejector tests were performed with both tracer gases released though a single ejector, and the concentration measured in the same manner as the dual gas dual ejector tests. The dual gas dual ejector tests showed excellent correlation, with R typically greater than 0.9. Variance was observed in the resulting regression line for each hood, likely due to non-symmetry between the two challenges caused by variables beyond the control of the investigators. Dual gas single ejector tests resulted in exceptional correlation, with R>0.99 typically for the consolidated data, with a slope of 1.0. These data indicate equivalent results for ASHRAE 110 performance testing using either SF6 or N2O, indicating N2O as an applicable alternate tracer gas.
Advanced Techniques in Crash Impact Protection and Emergency Egress from Air Transport Aircraft
1976-06-01
4.5.1 Integrated Upper Torso Restraint 70 4.5.1.1 NASA Ames Integrated System 71 4.5.1.2 Chrysler Corporate System 74 4.5.2 Y-Yoke Inertia Reel...3. International Husky Corporation /Boeing future concept lifting-body air freighter [Aviation Week, 1974 (32)] 4 4. Possible configuration of...39 24. Demonstration of passenger donning Schjeldahl "S" model "safety" hood in Chrysler Corporation Gulfstream. This smoke hood is presently in use
Grimbergen, T W M; Wiegman, M M
2007-01-01
In order to arrive at recommendations for guidelines on maximum allowable quantities of radioactive material in laboratories, a proposed mathematical model was used for the calculation of transfer fractions for the air pathway. A set of incident scenarios was defined, including spilling, leakage and failure of the fume hood. For these 'common incidents', dose constraints of 1 mSv and 0.1 mSv are proposed in case the operations are being performed in a controlled area and supervised area, respectively. In addition, a dose constraint of 1 microSv is proposed for each operation under regular working conditions. Combining these dose constraints and the transfer fractions calculated with the proposed model, maximum allowable quantities were calculated for different laboratory operations and situations. Provided that the calculated transfer fractions can be experimentally validated and the dose constraints are acceptable, it can be concluded from the results that the dose constraint for incidents is the most restrictive one. For non-volatile materials this approach leads to quantities much larger than commonly accepted. In those cases, the results of the calculations in this study suggest that limitation of the quantity of radioactive material, which can be handled safely, should be based on other considerations than the inhalation risks. Examples of such considerations might be the level of external exposure, uncontrolled spread of radioactive material by surface contamination, emissions in the environment and severe accidents like fire.
Characterization and comparison of emissions from rudimentary waste disposal technologies
Results from 2011 simulation of burn pit emissions and air curtain incinerator emissions, recent developments in methods for open air sampling, comparison of waste energy technologies, current SERDP programs in this area.
Dewald, Eva; Gube, Monika; Baumann, Ralf; Bertram, Jens; Kossack, Veronika; Lenz, Klaus; Reisgen, Uwe; Kraus, Thomas; Brand, Peter
2015-08-01
Emissions from a particular welding process, metal inert gas brazing of zinc-coated steel, induce an increase in C-reactive protein. In this study, it was investigated whether inflammatory effects could also be observed for other welding procedures. Twelve male subjects were separately exposed to (1) manual metal arc welding fumes, (2) filtered air, and (3) metal active gas welding fumes for 6 hours. Inflammatory markers were measured in serum before, and directly, 1 and 7 days after exposure. Although C-reactive protein concentrations remained unchanged, neutrophil concentrations increased directly after exposure to manual metal arc welding fumes, and endothelin-1 concentrations increased directly and 24 hours after exposure. After exposure to metal active gas and filtered air, endothelin-1 concentrations decreased. The increase in the concentrations of neutrophils and endothelin-1 may characterize a subclinical inflammatory reaction, whereas the decrease of endothelin-1 may indicate stress reduction.
Organiscak, J.A.; Beck, T.W.
2015-01-01
The U.S. National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) has recently studied several redirected scrubber discharge configurations in its full-scale continuous miner gallery for both dust and gas control when using an exhaust face ventilation system. Dust and gas measurements around the continuous mining machine in the laboratory showed that the conventional scrubber discharge directed outby the face with a 12.2-m (40-ft) exhaust curtain setback appeared to be one of the better configurations for controlling dust and gas. Redirecting all the air toward the face equally up both sides of the machine increased the dust and gas concentrations around the machine. When all of the air was redirected toward the face on the off-curtain side of the machine, gas accumulations tended to be reduced at the face, at the expense of increased dust levels in the return and on the curtain side of the mining machine. A 6.1-m (20-ft) exhaust curtain setback without the scrubber operating resulted in the lowest dust levels around the continuous mining machine, but this configuration resulted in some of the highest levels of dust in the return and gas on the off-curtain side of the mining face. Two field studies showed some similarities to the laboratory findings, with elevated dust levels at the rear corners of the continuous miner when all of the scrubber exhaust was redirected toward the face either up the off-tubing side or equally up both sides of the mining machine. PMID:26251566
Evaluation of consumer monitors to measure particulate matter.
Sousan, Sinan; Koehler, Kirsten; Hallett, Laura; Peters, Thomas M
2017-05-01
Recently, inexpensive (<$300) consumer aerosol monitors (CAMs) targeted for use in homes have become available. We evaluated the accuracy, bias, and precision of three CAMs (Foobot from Airoxlab, Speck from Carnegie Mellon University, and AirBeam from HabitatMap) for measuring mass concentrations in occupational settings. In a laboratory study, PM 2.5 measured with the CAMs and a medium-cost aerosol photometer (personal DataRAM 1500, Thermo Scientific) were compared to that from reference instruments for three aerosols (salt, welding fume, and Arizona road dust, ARD) at concentrations up to 8500 μg/m 3 . Three of each type of CAM were included to estimate precision. Compared to reference instruments, mass concentrations measured with the Foobot (r-value = 0.99) and medium-cost photometer (r-value = 0.99) show strong correlation, whereas those from the Speck (r-value range 0.88 - 0.99) and AirBeam (0.7 - 0.96) were less correlated. The Foobot bias was (-12%) for ARD and measurements were similar to the medium-cost instrument. Foobot bias was (< -46%) for salt and welding fume aerosols. Speck bias was at 18% salt for ARD and -86% for welding fume. AirBeam bias was (-36%) for salt and (-83%) for welding fume. All three photometers had a bias (< -82%) for welding fume. Precision was excellent for the Foobot (coefficient of variation range: 5% to 8%) and AirBeam (2% to 9%), but poorer for the Speck (8% to 25%). These findings suggest that the Foobot, with a linear response to different aerosol types and good precision, can provide reasonable estimates of PM 2.5 in the workplace after site-specific calibration to account for particle size and composition.
Pesticide deposition on coveralls during vineyard applications.
Coffman, C W; Obendorf, S K; Derksen, R C
1999-08-01
Deposition of pesticide on the clothing of the applicator was studied in a commercial vineyard using two different application technologies. A typical air-assisted sprayer with centrifugal fans delivered a concentrated spray. A tunnel or hooded sprayer was used at two carrier rates-high volume, low concentration versus low volume, high concentration-to apply Dithane M-45, an agricultural fungicide, at 3,375 g/ha on a light to medium density canopy. Deposition of pesticide was on the coveralls worn by the operator for all applications with a deposition range of 0.43 to 0.63 ng/cm2. The deposition on the clothing was higher for the air-assist sprayer than for the hooded sprayer. However, reducing the volume of water in the non-air assist hooded sprayer offered no advantage in terms of decreasing operator exposure. While the deposition of pesticide on the coveralls of the applicator was fairly uniformly distributed on the garment surface, the neck, shoulder, and upper right arm of our right-handed operator had the highest amount of pesticide deposit and the lower left quadrant of the garment had the lowest deposition. Results of this study indicate that vineyard applicator exposure can be reduced by use of the hooded non-air assisted sprayer and that extra protection is needed in the region of the neck, shoulder, and arm, and attention to the habits of the tractor driver is required.http://link.springer-ny. com/link/service/journals/00244/bibs/37n2p273.html
42 CFR 84.130 - Supplied-air respirators; description.
Code of Federal Regulations, 2010 CFR
2010-10-01
... material to protect the window(s) of facepieces, hoods, and helmets which do not unduly interfere with the wearer's vision and permit easy access to the external surface of such window(s) for cleaning. (c) Type..., glass, woven wire, sheet metal, or other suitable material to protect the window(s) of facepieces, hoods...
Deformed Shape Analysis of Coupled Glazing Systems
2013-09-01
Tyndall Air Force Base, Florida, USA ABSTRACT Glazing in storefront and curtain wall configurations is increasingly used in areas subjected to... AIR FORCE CIVIL ENGINEER CENTER READINESS DIRECTORATE Requirements & Acquisition Division United States Air Force Tyndall Air Force...Antonio, Texas; %Omaha, Nebraska #Jacobs Technology, Fort Walton Beach, Florida Air Force Civil Engineer Center Readiness Directorate Requirements
INSIDE IAQ (SPRING/SUMMER 2001)
The newsletter discusses results of research on volatile organic compound (VOC) emissions from photocopier toners, hazardous air pollutants (HAPs) emitted by shower curtains, asthma intervention in Boston public housing, air pollution from burning candles, and the impact of ozone...
Torén, Kjell; Bergdahl, Ingvar A; Nilsson, Tohr; Järvholm, Bengt
2007-01-01
Objectives A growing number of epidemiological studies are showing that ambient exposure to particulate matter air pollution is a risk factor for cardiovascular disease; however, whether occupational exposure increases this risk is not clear. The aim of the present study was to examine whether occupational exposure to particulate air pollution increases the risk for ischaemic heart disease and cerebrovascular disease. Methods The study population was a cohort of 176 309 occupationally exposed Swedish male construction workers and 71 778 unexposed male construction workers. The definition of exposure to inorganic dust (asbestos, man‐made mineral fibres, dust from cement, concrete and quartz), wood dust, fumes (metal fumes, asphalt fumes and diesel exhaust) and gases and irritants (organic solvents and reactive chemicals) was based on a job‐exposure matrix with focus on exposure in the mid‐1970s. The cohort was followed from 1971 to 2002 with regard to mortality to ischaemic heart disease and cerebrovascular disease. Relative risks (RR) were obtained by the person‐years method and from Poisson regression models adjusting for baseline values of blood pressure, body mass index, age and smoking habits. Results Any occupational particulate air pollution was associated with an increased risk for ischemic heart disease (RR 1.13, 95% CI 1.07 to 1.19), but there was no increased risk for cerebrovascular disease (RR 0.97, 95% CI 0.88 to 1.07). There was an increased risk for ischaemic heart disease and exposure to inorganic dust (RR 1.07, 95% CI 1.03 to 1.12) and exposure to fumes (RR 1.05, 95% CI 1.00 to 1.10), especially diesel exhaust (RR 1.18, 95% CI 1.13 to 1.24). There was no significantly increased risk for cerebrovascular disease and exposure to inorganic dust, fumes or wood dust. Conclusions Occupational exposure to particulate air pollution, especially diesel exhaust, among construction workers increases the risk for ischaemic heart disease. PMID:17303673
NASA Astrophysics Data System (ADS)
Artous, Sébastien; Bombardier, Pierre; Derrough, Samir; Locatelli, Dominique; Nobile, Pierre; Durand, Catherine
2013-04-01
The implementation in many products of manufactured nanoparticles is in strong growth and raises new questions. For this purpose, the CEA - NanoSafety Platform is developing various research topics for health and safety, environment and nanoparticles exposure in professional activities. The working group Nano-CERT/MTD, driven by INERIS, federates actors of the sector: experts, research organizations, industrial users and manufacturers of collective protection. The main activity of this group is to establish specific guidelines or a voluntary certification of collective protection, at a national scale, but with the possibility of a further extension at an European level. The group aims to establish an experimental protocol of certification to characterize collective protections for workers faced with nanomaterials potential exposure. The NanoSafety Platform provides in this presentation a method of collective protection characterization based on the developments in nanoparticles metrology and on the study of existing standards and practices in related areas (chemicals, dust, microbiological and nuclear). This study presents the results obtained during the experimental characterization of a potential nanoparticles transfer in a prototype laboratory fume hood by the use of a particulate tracer of sodium-fluorescein. The efficiency of the equipment and more specifically the efficiency of dynamical air barrier is evaluated, with the experimental results, by calculating the backward diffusion coefficient.
40 CFR 60.2850 - What must I do if I close my air curtain incinerator and then restart it?
Code of Federal Regulations, 2014 CFR
2014-07-01
... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model...
Code of Federal Regulations, 2014 CFR
2014-07-01
... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY... Units Model Rule-Air Curtain Incinerators § 60.2815 What are my requirements for meeting increments of...
40 CFR 60.2825 - What must I include in the notifications of achievement of increments of progress?
Code of Federal Regulations, 2014 CFR
2014-07-01
... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY... Units Model Rule-Air Curtain Incinerators § 60.2825 What must I include in the notifications of...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-10
... Promulgation of Air Quality Implementation Plans; Colorado; Revisions to Regulation Number 1 AGENCY... Number 1 (revisions to the performance testing requirements for air curtain destructors). Colorado... concurrent with Colorado's Regulation Number 1 revision request will be acted on at a later date. In the...
40 CFR 60.2245 - What is an air curtain incinerator?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Industrial Solid Waste Incineration Units for Which Construction Is Commenced After November 30, 1999 or for... and controlled air technology such as mass burn, modular, and fluidized bed combustors.) (b) Air....2260). (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent mixture of only wood...
Code of Federal Regulations, 2013 CFR
2013-10-01
... frontal air bag deployment crash, capture and record the current deployment data. In a side or side curtain/tube air bag deployment crash, where lateral delta-V is recorded by the EDR, capture and record the current deployment data. The memory for the air bag deployment event must be locked to prevent any...
Code of Federal Regulations, 2014 CFR
2014-10-01
... frontal air bag deployment crash, capture and record the current deployment data. In a side or side curtain/tube air bag deployment crash, where lateral delta-V is recorded by the EDR, capture and record the current deployment data. The memory for the air bag deployment event must be locked to prevent any...
Code of Federal Regulations, 2012 CFR
2012-10-01
... frontal air bag deployment crash, capture and record the current deployment data. In a side or side curtain/tube air bag deployment crash, where lateral delta-V is recorded by the EDR, capture and record the current deployment data. The memory for the air bag deployment event must be locked to prevent any...
Efficient management of cardiovascular risk screening programs
NASA Technical Reports Server (NTRS)
Roth, Carol
1993-01-01
The Environmental Health Unit, located on-site at the the Goddard Space Flight Center (GSFC), is responsible for the implementation of the Center's Employee Environmental and Occupational Health Program. The Health Unit, Health Physics (HP), and Industrial Hygiene (IH) staffs collaborate to provide quality service to the employees at GSFC. The Health Unit staff identifies, evaluates, and ensures the control of occupational hazards on the Center. In the past, components of the Industrial Hygiene Program have included the Industrial Hygiene Health Hazard Identification Program (IHHIP), the Hearing Conservation Program (HCP), the Hazard Communication Program, and the bi-annual fume hood survey. More recently, the Environmental Health Unit has expanded its services by adding the Ergonomics Program. Various aspects of the Ergonomics Program are discussed.
42 CFR 84.131 - Supplied-air respirators; required components.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Facepiece, hood, or helmet; (2) Air supply valve, orifice, or demand or pressure-demand regulator; (3) Hand... 42 Public Health 1 2010-10-01 2010-10-01 false Supplied-air respirators; required components. 84... Supplied-Air Respirators § 84.131 Supplied-air respirators; required components. (a) Each supplied-air...
Canadian and US agencies use bubbles to aid salmon
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
B.C. Hydro, Canada's federal Department of Fisheries and Oceans, and the Bureau of Reclamation in the US have implemented unique bubbler systems that release compressed air to aid fish migration and improve spawning habitat. In each case, compressed air equipment produced bubbles that lifted cool water from a lake bottom to displace warmer water on top. An experimental project during the summer of 1992, involving BC Hydro and the Department of Fisheries and Oceans, succeeded in reducing the mortality rate of sockeye salmon on their migration up the Somass River from the Alberni Inlet to Great Central Lake on Vancouvermore » Island. The bubbler system cooled the water to aid the migration of hundreds of thousands of fish who were reluctant to continue upstream due to exceptionally warm water temperatures. Participants in the project suspended a large lead-weighted plastic curtain (more than 12 meters tall and extending the length of three football fields) from a series of floats across the outlet of Grand Central Lake. Compressed air equipment was installed behind the curtain to produce bubbles to lift cool water from the lake bottom. Water flowing into the river ranged from 1 to 3 degrees cooler than water on the other side of the curtain.« less
29 CFR 1915.51 - Ventilation and protection in welding, cutting and heating.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) When inert-gas metal-arc welding is being performed on stainless steel, the requirements of paragraph... the number of air changes necessary to maintain welding fumes and smoke within safe limits. (iii... as to remove fumes and smoke at the source and keep the concentration of them in the breathing zone...
29 CFR 1915.51 - Ventilation and protection in welding, cutting and heating.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) When inert-gas metal-arc welding is being performed on stainless steel, the requirements of paragraph... the number of air changes necessary to maintain welding fumes and smoke within safe limits. (iii... as to remove fumes and smoke at the source and keep the concentration of them in the breathing zone...
29 CFR 1915.51 - Ventilation and protection in welding, cutting and heating.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) When inert-gas metal-arc welding is being performed on stainless steel, the requirements of paragraph... the number of air changes necessary to maintain welding fumes and smoke within safe limits. (iii... as to remove fumes and smoke at the source and keep the concentration of them in the breathing zone...
29 CFR 1915.51 - Ventilation and protection in welding, cutting and heating.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) When inert-gas metal-arc welding is being performed on stainless steel, the requirements of paragraph... the number of air changes necessary to maintain welding fumes and smoke within safe limits. (iii... as to remove fumes and smoke at the source and keep the concentration of them in the breathing zone...
Scheme for air treatment in welding workshop
NASA Astrophysics Data System (ADS)
Wang, Gang; Wu, Jin
2017-04-01
There are two major ways to control the pollution of welding fume which are respectively local purification and comprehensive purification. In this paper, the practical welding workshop at school is taken as an example to realize fume treatment in different training conditions by adopting the scheme in which two major ways are combined.
Pulmonary effects induced by ultrafine PTFE particles.
Johnston, C J; Finkelstein, J N; Mercer, P; Corson, N; Gelein, R; Oberdörster, G
2000-11-01
PTFE (polytetrafluoroethylene) fumes consisting of large numbers of ultrafine (uf) particles and low concentrations of gas-phase compounds can cause severe acute lung injury. Our studies were designed to test three hypotheses: (i) uf PTFE fume particles are causally involved in the induction of acute lung injury, (ii) uf PTFE elicit greater pulmonary effects than larger sized PTFE accumulation mode particles, and (iii) preexposure to the uf PTFE fume particles will induce tolerance. We used uf Teflon (PTFE) fumes (count median particle size approximately 16 nm) generated by heating PTFE in a tube furnace to 486 degrees C to evaluate principles of ultrafine particle toxicity. Teflon fumes at ultrafine particle concentrations of 50 microg/m(3) were extremely toxic to rats when inhaled for only 15 min. We found that when generated in argon, the ultrafine Teflon particles alone are not toxic at these exposure conditions; neither were Teflon fume gas-phase constituents when generated in air. Only the combination of both phases when generated in air caused high toxicity, suggesting either the existence of radicals on the surface or a carrier mechanism of the ultrafine particles for adsorbed gas compounds. Aging of the fresh Teflon fumes for 3.5 min led to a predicted coagulation to >100 nm particles which no longer caused toxicity in exposed animals. This result is consistent with a greater toxicity of ultrafine particles compared to accumulation mode particles, although changes in particle surface chemistry during the aging process may have contributed to the diminished toxicity. Furthermore, the pulmonary toxicity of the ultrafine Teflon fumes could be prevented by adapting the animals with short 5-min exposures on 3 days prior to a 15-min exposure. Messages encoding antioxidants and chemokines were increased substantially in nonadapted animals, yet were unaltered in adapted animals. This study shows the importance of preexposure history for the susceptibility to acute ultrafine particle effects. Copyright 2000 Academic Press.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Logue, Jennifer M; Singer, Brett
Range hood use during residential cooking is essential to maintaining good indoor air quality. However, widespread use will impact the energy demand of the U.S. housing stock. This paper describes a modeling study to determine site energy, source energy, and consumer costs for comprehensive range hood use. To estimate the energy impacts for all 113 million homes in the U.S., we extrapolated from the simulation of a representative weighted sample of 50,000 virtual homes developed from the 2009 Residential Energy Consumption Survey database. A physics-based simulation model that considered fan energy, energy to condition additional incoming air, and the effectmore » on home heating and cooling due to exhausting the heat from cooking was applied to each home. Hoods performing at a level common to hoods currently in U.S. homes would require 19?33 TWh [69?120 PJ] of site energy, 31?53 TWh [110-190 PJ] of source energy; and would cost consumers $1.2?2.1 billion (U.S.$2010) annually in the U.S. housing stock. The average household would spend less than $15 annually. Reducing required airflow, e.g. with designs that promote better pollutant capture has more energy saving potential, on average, than improving fan efficiency.« less
Urine chromium as an estimator of air exposure to stainless steel welding fumes.
Sjögren, B; Hedström, L; Ulfvarson, U
1983-01-01
Welding stainless steel with covered electrodes, also called manual metal arc welding, generates hexavalent airborne chromium. Chromium concentrations in air and post-shift urine samples, collected the same arbitrarily chosen working day, showed a linear relationship. Since post-shift urine samples reflect chromium concentrations of both current and previous stainless steel welding fume exposure, individual urine measurements are suggested as approximate although not exact estimators of current exposure. This study evaluates the practical importance of such measurements by means of confidence limits and tests of validity.
29 CFR 1926.353 - Ventilation and protection in welding, cutting, and heating.
Code of Federal Regulations, 2013 CFR
2013-07-01
... welding is being performed on stainless steel, the requirements of paragraph (c)(2) of this section shall... the number of air changes necessary to maintain welding fumes and smoke within safe limits, as defined... sufficient capacity and so arranged as to remove fumes and smoke at the source and keep the concentration of...
29 CFR 1926.353 - Ventilation and protection in welding, cutting, and heating.
Code of Federal Regulations, 2014 CFR
2014-07-01
... welding is being performed on stainless steel, the requirements of paragraph (c)(2) of this section shall... the number of air changes necessary to maintain welding fumes and smoke within safe limits, as defined... sufficient capacity and so arranged as to remove fumes and smoke at the source and keep the concentration of...
29 CFR 1926.353 - Ventilation and protection in welding, cutting, and heating.
Code of Federal Regulations, 2012 CFR
2012-07-01
... welding is being performed on stainless steel, the requirements of paragraph (c)(2) of this section shall... the number of air changes necessary to maintain welding fumes and smoke within safe limits, as defined... sufficient capacity and so arranged as to remove fumes and smoke at the source and keep the concentration of...
29 CFR 1926.353 - Ventilation and protection in welding, cutting, and heating.
Code of Federal Regulations, 2011 CFR
2011-07-01
... welding is being performed on stainless steel, the requirements of paragraph (c)(2) of this section shall... the number of air changes necessary to maintain welding fumes and smoke within safe limits, as defined... sufficient capacity and so arranged as to remove fumes and smoke at the source and keep the concentration of...
Processes involved in the development of latent fingerprints using the cyanoacrylate fuming method.
Lewis, L A; Smithwick, R W; Devault, G L; Bolinger, B; Lewis, S A
2001-03-01
Chemical processes involved in the development of latent fingerprints using the cyanoacrylate fuming method have been studied. Two major types of latent prints have been investigated-clean and oily prints. Scanning electron microscopy (SEM) has been used as a tool for determining the morphology of the polymer developed separately on clean and oily prints after cyanoacrylate fuming. A correlation between the chemical composition of an aged latent fingerprint, prior to development, and the quality of a developed fingerprint has been observed in the morphology. The moisture in the print prior to fuming has been found to be more important than the moisture in the air during fuming for the development of a useful latent print. In addition, the amount of time required to develop a high quality latent print has been found to be within 2 min. The cyanoacrylate polymerization process is extremely rapid. When heat is used to accelerate the fuming process, typically a period of 2 min is required to develop the print. The optimum development time depends upon the concentration of cyanoacrylate vapors within the enclosure.
Breathing Better with a COPD Diagnosis
... and strong fumes. Stay indoors when the outside air quality is poor, and avoid places where there might ... H When lungs are healthy, the airways and air sacs have an elastic, flexible quality. They expand to fill with air and then ...
Yang, Show-Yi; Lin, Jia-Ming; Young, Li-Hao; Chang, Ching-Wen
2018-04-07
We investigate exposure to welding fume metals in pipeline construction, which are responsible for severe respiratory problems. We analyzed air samples obtained using size-fractioning cascade impactors that were attached to the welders performing shielded metal and gas tungsten arc welding outdoors. Iron, aluminum, zinc, chromium, manganese, copper, nickel, and lead concentrations in the water-soluble (WS) and water-insoluble (WI) portions were determined separately, using inductively coupled plasma mass spectrometry. The mass-size distribution of welding fume matches a log-normal distribution with two modes. The metal concentrations in the welding fume were ranked as follows: Fe > Al > Zn > Cr > Mn > Ni > Cu > Pb. In the WS portion, the capacities of metals dissolving in water are correlated with the metal species but particle sizes. Particularly, Zn, Mn, and Pb exhibit relatively higher capacities than Cu, Cr, Al, Fe, and Ni. Exposure of the gas-exchange region of the lungs to WS metals were in the range of 4.9% to 34.6% of the corresponding metals in air by considering the particle-size selection in lungs, metal composition by particle size, and the capacities of each metal dissolving in water.
Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.
Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C
2015-11-01
Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
30 CFR 75.326 - Mean entry air velocity.
Code of Federal Regulations, 2013 CFR
2013-07-01
... exhausting face ventilation systems, the mean entry air velocity shall be at least 60 feet per minute reaching each working face where coal is being cut, mined, drilled for blasting, or loaded, and to any... the inby end of the line curtain, ventilation tubing, or other face ventilation control devices. [61...
30 CFR 75.326 - Mean entry air velocity.
Code of Federal Regulations, 2011 CFR
2011-07-01
... exhausting face ventilation systems, the mean entry air velocity shall be at least 60 feet per minute reaching each working face where coal is being cut, mined, drilled for blasting, or loaded, and to any... the inby end of the line curtain, ventilation tubing, or other face ventilation control devices. [61...
30 CFR 75.326 - Mean entry air velocity.
Code of Federal Regulations, 2010 CFR
2010-07-01
... exhausting face ventilation systems, the mean entry air velocity shall be at least 60 feet per minute reaching each working face where coal is being cut, mined, drilled for blasting, or loaded, and to any... the inby end of the line curtain, ventilation tubing, or other face ventilation control devices. [61...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singer, Brett C.; Pass, Rebecca Zarin; Delp, William W.
Combustion pollutant concentrations were measured during the scripted operation of natural gas cooking burners in nine homes. Boiling and simmering activities were conducted on the stovetop and in the oven with and without range hood exhaust ventilation or air mixing via a forced air system. Time-resolved concentrations of carbon dioxide (CO 2), nitric oxide (NO), nitrogen oxides (NO x), nitrogen dioxide (NO 2), particles with diameters of 6 nm or larger (PN), carbon monoxide (CO), and fine particulate matter (PM 2.5) were measured in the kitchen and bedroom area of each home. Four of the nine homes had kitchen 1more » h NO 2 exceed the national ambient air quality standard (100 ppb). In all homes, the highest 1 h integrated PN exceeded 2 × 10 5 cm -3-h, and the highest 4 h PN exceeded 3 × 10 5 cm -3-hr in the kitchen. Range hood performance varied widely, but one with a large capture volume and a measured flow of 108 L/s reduced concentrations 80–95%. Increased awareness of the need to ventilate when cooking, along with building standards for minimum range hood flow rates and volume, could substantially reduce exposures to NO 2 and ultrafine particles in homes.« less
NASA Astrophysics Data System (ADS)
Shahrabadi, Hamid; Sayareh, Sina; Sarkardeh, Hamed
2017-12-01
In the present research, effect of silica fume as an additive and oil polluted sands as aggregates on compressive strength of concrete were investigated experimentally. The amount of oil in the designed mixtures was assumed to be constant and equal to 2% of the sand weight. Silica fume accounting for 10%, 15% and 20% of the weight is added to the designed mixture. After preparation and curing, concrete specimens were placed into the three different conditions: fresh, brackish and saltwater environments (submerged in fresh water, alternation of exposed in air & submerged in sea water and submerged in sea water). The result of compressive strength tests shows that the compressive strength of the specimens consisting of silica fume increases significantly in comparison with the control specimens in all three environments. The compressive strength of the concrete with 15% silica fume content was about 30% to 50% higher than that of control specimens in all tested environments under the condition of using polluted aggregates in the designed mixture.
Wang, Lingling; Hu, Weiyue; Guan, Quanquan; Du, Guizhen; Chen, Ting; Wu, Wei; Wang, Yun; Wang, Xinru; Xia, Yankai
2018-01-15
Effects of indoor air pollution on neonatal birth weight has been studied for many years. In China, cooking oil fumes are important parts of indoor air pollution. However, whether cooking oil fume exposure during pregnancy affects birth weight in China remains poorly understood. The objective of this study was to examine the association between pregnancy exposure to cooking oil fumes and birth weight in a newly established prospective mother-child cohort in China. We finally included 1420 pregnant women from 2013 to 2015 and follow up for one year until the offspring was born. According to self-reported exposure status, we categorized mothers into non-exposure group and exposed group or three exposure time subgroups, including 0h/day, 0-1h/day and >1h/day respectively. By using multinomial logistics regression models, we found that pregnancy exposure to cooking oil fumes significantly increased the risk of large for gestational age (LGA, OR=1.58, 95% CI=1.15-2.18, P=4.88×10 -3 ). Additionally, compared to pregnant women who were in non-exposure group, 0-1h/day exposure elevated the risk of LGA (OR=1.69, 95% CI=1.22-2.33, P=1.63×10 -3 ), while >1h/day exposure elevated the risk of small for gestational age, but were not significant (SGA, OR=2.15, 95% CI=0.61-7.66, P=0.24). In the stratification analysis, women aged 25-29years and ≥30years were predisposed to the influence of cooking oil fumes and have LGA newborns (OR=1.73, 95% CI=1.09-2.75, P=0.02; OR=1.72, 95% CI=1.07-2.77, P=0.02, respectively). In conclusion, the present study suggests inverse U-shape dose response association between maternal exposure to cooking oil fumes during pregnancy and birth weight, and further studies are needed to verify the effect of cooking oil fumes on the birth weight. Copyright © 2017 Elsevier B.V. All rights reserved.
Antonini, James M; Stone, Sam; Roberts, Jenny R; Chen, Bean; Schwegler-Berry, Diane; Afshari, Aliakbar A; Frazer, David G
2007-09-15
Many welders have experienced bronchitis, metal fume fever, lung function changes, and an increase in the incidence of lung infection. Questions remain regarding the possible mechanisms associated with the potential pulmonary effects of welding fume exposure. The objective was to assess the early effects of stainless steel (SS) welding fume inhalation on lung injury, inflammation, and defense responses. Male Sprague-Dawley rats were exposed to gas metal arc-SS welding fume at a concentration of 15 or 40 mg/m(3) x 3 h/day for 1, 3, or 10 days. The control group was exposed to filtered air. To assess lung defense responses, some animals were intratracheally inoculated with 5x10(4) Listeria monocytogenes 1 day after the last exposure. Welding particles were collected during exposure, and elemental composition and particle size were determined. At 1, 4, 6, 11, 14, and 30 days after the final exposure, parameters of lung injury (lactate dehydrogenase and albumin) and inflammation (PMN influx) were measured in the bronchoalveolar lavage fluid. In addition, particle-induced effects on pulmonary clearance of bacteria and macrophage function were assessed. SS particles were composed of Fe, Cr, Mn, and Ni. Particle size distribution analysis indicated the mass median aerodynamic diameter of the generated fume to be 0.255 microm. Parameters of lung injury were significantly elevated at all time points post-exposure compared to controls except for 30 days. Interestingly, no significant difference in lung PMNs was observed between the SS and control groups at 1, 4, and 6 days post-exposure. After 6 days post-exposure, a dramatic increase in lung PMNs was observed in the SS group compared to air controls. Lung bacteria clearance and macrophage function were reduced and immune and inflammatory cytokines were altered in the SS group. In summary, short-term exposure of rats to SS welding fume caused significant lung damage and suppressed lung defense responses to bacterial infection, but had a delayed effect on pulmonary inflammation. Additional chronic inhalation studies are needed to further examine the lung effects associated with SS welding fume exposure.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Antonini, James M.; Stone, Sam; Roberts, Jenny R.
Many welders have experienced bronchitis, metal fume fever, lung function changes, and an increase in the incidence of lung infection. Questions remain regarding the possible mechanisms associated with the potential pulmonary effects of welding fume exposure. The objective was to assess the early effects of stainless steel (SS) welding fume inhalation on lung injury, inflammation, and defense responses. Male Sprague-Dawley rats were exposed to gas metal arc-SS welding fume at a concentration of 15 or 40 mg/m{sup 3} x 3 h/day for 1, 3, or 10 days. The control group was exposed to filtered air. To assess lung defense responses,more » some animals were intratracheally inoculated with 5 x 10{sup 4}Listeria monocytogenes 1 day after the last exposure. Welding particles were collected during exposure, and elemental composition and particle size were determined. At 1, 4, 6, 11, 14, and 30 days after the final exposure, parameters of lung injury (lactate dehydrogenase and albumin) and inflammation (PMN influx) were measured in the bronchoalveolar lavage fluid. In addition, particle-induced effects on pulmonary clearance of bacteria and macrophage function were assessed. SS particles were composed of Fe, Cr, Mn, and Ni. Particle size distribution analysis indicated the mass median aerodynamic diameter of the generated fume to be 0.255 {mu}m. Parameters of lung injury were significantly elevated at all time points post-exposure compared to controls except for 30 days. Interestingly, no significant difference in lung PMNs was observed between the SS and control groups at 1, 4, and 6 days post-exposure. After 6 days post-exposure, a dramatic increase in lung PMNs was observed in the SS group compared to air controls. Lung bacteria clearance and macrophage function were reduced and immune and inflammatory cytokines were altered in the SS group. In summary, short-term exposure of rats to SS welding fume caused significant lung damage and suppressed lung defense responses to bacterial infection, but had a delayed effect on pulmonary inflammation. Additional chronic inhalation studies are needed to further examine the lung effects associated with SS welding fume exposure.« less
Inhalation of gas metal arc-stainless steel welding fume promotes lung tumorigenesis in A/J mice.
Falcone, Lauryn M; Erdely, Aaron; Meighan, Terence G; Battelli, Lori A; Salmen, Rebecca; McKinney, Walter; Stone, Samuel; Cumpston, Amy; Cumpston, Jared; Andrews, Ronnee N; Kashon, Michael; Antonini, James M; Zeidler-Erdely, Patti C
2017-08-01
Epidemiologic studies suggest an increased risk of lung cancer with exposure to welding fumes, but controlled animal studies are needed to support this association. Oropharyngeal aspiration of collected "aged" gas metal arc-stainless steel (GMA-SS) welding fume has been shown by our laboratory to promote lung tumor formation in vivo using a two-stage initiation-promotion model. Our objective in this study was to determine whether inhalation of freshly generated GMA-SS welding fume also acts as a lung tumor promoter in lung tumor-susceptible mice. Male A/J mice received intraperitoneal (IP) injections of corn oil or the chemical initiator 3-methylcholanthrene (MCA; 10 µg/g) and 1 week later were exposed by whole-body inhalation to air or GMA-SS welding aerosols for 4 h/d × 4 d/w × 9 w at a target concentration of 40 mg/m 3 . Lung nodules were enumerated at 30 weeks post-initiation. GMA-SS fume significantly promoted lung tumor multiplicity in A/J mice initiated with MCA (16.11 ± 1.18) compared to MCA/air-exposed mice (7.93 ± 0.82). Histopathological analysis found that the increased number of lung nodules in the MCA/GMA-SS group were hyperplasias and adenomas, which was consistent with developing lung tumorigenesis. Metal deposition analysis in the lung revealed a lower deposited dose, approximately fivefold compared to our previous aspiration study, still elicited a significant lung tumorigenic response. In conclusion, this study demonstrates that inhaling GMA-SS welding fume promotes lung tumorigenesis in vivo which is consistent with the epidemiologic studies that show welders may be at an increased risk for lung cancer.
NASA Astrophysics Data System (ADS)
Matsushima, U.; Kardjilov, N.; Hilger, A.; Manke, I.; Shono, H.; Herppich, W. B.
2009-06-01
Photosynthetic efficacy and auto-exhaust-fume resistance of street trees were evaluated by cold neutron radiography (CNR) with D 2O tracer and chlorophyll fluorescence (CF) imaging. With these techniques, information on the responses of water usage and photosynthetic activity of plants exposed to simulate toxic auto-exhaust fumes (2 ppm SO 2 in air) were obtained. Branches of hibiscus trees were detached, placed into a tub with aerated water and used for the experiments after rooting. A CF image was taken before SO 2 was applied for 1 h. During the experiment, CNR and CF imaging were conduced. H 2O and D 2O in the plant container were exchanged every 30 min to observe water uptake. D 2O tracer clearly showed water uptake into the hibiscus stem during each treatment. When the atmosphere was changed from simulated auto-exhaust fumes to normal air again, the amount of D 2O and, hence, water uptake increased. CF imaging was well suited to evaluate the effects of SO 2 as simulated toxic auto-exhaust fumes on plants. The maximum photochemical efficiency ( Fv/ Fm), a sensitive indicator of the efficacy and the integrity of plants' photosynthesis, immediately dropped by 30% after supplying the simulated auto-exhaust fumes. This indicates that toxic auto-exhaust fumes negatively affected the photosynthetic activity of hibiscus leaves. Simultaneous CNR and CF imaging successfully visualized variations of photosynthetic activity and water uptake in the sample. Thus, this combination method was effective to non-destructive analyze the physiological status of plants.
Manganese and welding fume exposure and control in construction.
Meeker, John D; Susi, Pam; Flynn, Michael R
2007-12-01
Overexposure to welding fume constituents, particularly manganese, is of concern in the construction industry due to the prevalence of welding and the scarcity of engineering controls. The control effectiveness of a commercially available portable local exhaust ventilation (LEV) unit was assessed. It consisted of a portable vacuum and a small bell-shaped hood connected by a flexible 2 inch (50.8 mm) diameter hose, in both experimental and field settings. The experimental testing was done in a semienclosed booth at a pipefitter training facility. Five paired trials of LEV control vs. no control, each approximately 1 hr in duration and conducted during two successive welds of 6 inch (152.4 mm) diameter carbon steel pipe were run in random order. Breathing zone samples were collected outside the welding hood during each trial. In the field scenario, full-shift breathing zone samples were collected from two pipefitters welding carbon steel pipe for a chiller installation on a commercial construction project. Eight days of full-shift sampling were conducted on both workers (n = 16), and the LEV was used by one of the two workers on an alternating basis for 7 of the days. All samples were collected with personal sample pumps calibrated at 2 L/min. Filter cassettes were analyzed for total particulate and manganese concentration by a certified laboratory. In the experimental setting, use of the portable LEV resulted in a 75% reduction in manganese exposure (mean 13 microg/m(3) vs. 51 microg/m(3); p < 0.05) and a 60% reduction in total particulate (mean 0.74 mg/m(3) vs. 1.83 mg/m(3); p < 0.05). In the field setting, LEV use resulted in a 53% reduction in manganese exposure (geometric mean 46 microg/m(3) vs. 97 microg/m(3); p < 0.05) but only a 10% reduction in total particulate (geometric mean 4.5 mg/m(3) vs. 5.0 mg/m(3); p > 0.05). These results demonstrate that LEV use can reduce manganese exposure associated with welding tasks in construction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gajjar, Rachna M.; Kasting, Gerald B., E-mail: Gerald.Kasting@uc.edu
The overall goal of this research was to further develop and improve an existing skin diffusion model by experimentally confirming the predicted absorption rates of topically-applied volatile organic compounds (VOCs) based on their physicochemical properties, the skin surface temperature, and the wind velocity. In vitro human skin permeation of two hydrophilic solvents (acetone and ethanol) and two lipophilic solvents (benzene and 1,2-dichloroethane) was studied in Franz cells placed in a fume hood. Four doses of each {sup 14}C-radiolabed compound were tested — 5, 10, 20, and 40 μL cm{sup −2}, corresponding to specific doses ranging in mass from 5.0 tomore » 63 mg cm{sup −2}. The maximum percentage of radiolabel absorbed into the receptor solutions for all test conditions was 0.3%. Although the absolute absorption of each solvent increased with dose, percentage absorption decreased. This decrease was consistent with the concept of a stratum corneum deposition region, which traps small amounts of solvent in the upper skin layers, decreasing the evaporation rate. The diffusion model satisfactorily described the cumulative absorption of ethanol; however, values for the other VOCs were underpredicted in a manner related to their ability to disrupt or solubilize skin lipids. In order to more closely describe the permeation data, significant increases in the stratum corneum/water partition coefficients, K{sub sc}, and modest changes to the diffusion coefficients, D{sub sc}, were required. The analysis provided strong evidence for both skin swelling and barrier disruption by VOCs, even by the minute amounts absorbed under these in vitro test conditions. - Highlights: • Human skin absorption of small doses of VOCs was measured in vitro in a fume hood. • The VOCs tested were ethanol, acetone, benzene and 1,2-dichloroethane. • Fraction of dose absorbed for all compounds at all doses tested was less than 0.3%. • The more aggressive VOCs absorbed at higher levels than diffusion model predictions. • We conclude that even small exposures to VOCs temporarily alter skin permeability.« less
Demonstration and Field Test of airjacket technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Faulkner, D.; Fisk, W.J.; Gadgil, A.J.
1998-06-01
There are approximately 600,000 paint spray workers in the United States applying paints and coatings with some type of sprayer. Approximately 5% of these spray workers are in the South Coast Air Quality Management District (SCAQMD). These spray workers apply paints or other coatings to products such as bridges, houses, automobiles, wood and metal furniture, and other consumer and industrial products. The materials being sprayed include exterior and interior paints, lacquers, primers, shellacs, stains and varnishes. Our experimental findings indicate that the Airjacket does not significantly reduce the exposure of spray workers to paint fumes during HVLP spraying. The differencemore » between ideal and actual spray paint procedures influence the mechanisms driving spray workers exposures to paint fumes and influence the viability of the Airjacket technology. In the ideal procedure, for which the Airjacket was conceived, the spray worker's exposure to paint fumes is due largely to the formation of a recirculating eddy between the spray worker and the object painted. The Airjacket ejects air to diminish and ventilate this eddy. In actual practice, exposures may result largely from directing paint upstream and from the bounce-back of the air/paint jet of the object being painted. The Airjacket, would not be expected to dramatically reduce exposures to paint fumes when the paint is not directed downstream or when the bounce-back of paint on the object creates a cloud of paint aerosols around the spray worker.« less
NASA Astrophysics Data System (ADS)
McQuillen, Isaac; Phelps, LeEllen; Warner, Mark; Hubbard, Robert
2016-08-01
Implementation of an air curtain at the thermal boundary between conditioned and ambient spaces allows for observation over wavelength ranges not practical when using optical glass as a window. The air knife model of the Daniel K. Inouye Solar Telescope (DKIST) project, a 4-meter solar observatory that will be built on Haleakalā, Hawai'i, deploys such an air curtain while also supplying ventilation through the ceiling of the coudé laboratory. The findings of computational fluid dynamics (CFD) analysis and subsequent changes to the air knife model are presented. Major design constraints include adherence to the Interface Control Document (ICD), separation of ambient and conditioned air, unidirectional outflow into the coudé laboratory, integration of a deployable glass window, and maintenance and accessibility requirements. Optimized design of the air knife successfully holds full 12 Pa backpressure under temperature gradients of up to 20°C while maintaining unidirectional outflow. This is a significant improvement upon the .25 Pa pressure differential that the initial configuration, tested by Linden and Phelps, indicated the curtain could hold. CFD post- processing, developed by Vogiatzis, is validated against interferometry results of initial air knife seeing evaluation, performed by Hubbard and Schoening. This is done by developing a CFD simulation of the initial experiment and using Vogiatzis' method to calculate error introduced along the optical path. Seeing error, for both temperature differentials tested in the initial experiment, match well with seeing results obtained from the CFD analysis and thus validate the post-processing model. Application of this model to the realizable air knife assembly yields seeing errors that are well within the error budget under which the air knife interface falls, even with a temperature differential of 20°C between laboratory and ambient spaces. With ambient temperature set to 0°C and conditioned temperature set to 20°C, representing the worst-case temperature gradient, the spatial rms wavefront error in units of wavelength is 0.178 (88.69 nm at λ = 500 nm).
30 CFR 56.5002 - Exposure monitoring.
Code of Federal Regulations, 2010 CFR
2010-07-01
... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Air Quality and Physical Agents Air Quality § 56.5002 Exposure monitoring. Dust, gas, mist, and fume surveys shall be conducted as...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 2 2014-01-01 2014-01-01 false Air-cured. 29.6002 Section 29.6002 Agriculture... INSPECTION Standards Definitions § 29.6002 Air-cured. Tobacco cured under natural atmospheric conditions..., pole-burn, and shed-burn in damp weather. Air-cured tobacco should not carry the odor of smoke or fumes...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 2 2013-01-01 2013-01-01 false Air-cured. 29.6002 Section 29.6002 Agriculture... INSPECTION Standards Definitions § 29.6002 Air-cured. Tobacco cured under natural atmospheric conditions..., pole-burn, and shed-burn in damp weather. Air-cured tobacco should not carry the odor of smoke or fumes...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 2 2012-01-01 2012-01-01 false Air-cured. 29.6002 Section 29.6002 Agriculture... INSPECTION Standards Definitions § 29.6002 Air-cured. Tobacco cured under natural atmospheric conditions..., pole-burn, and shed-burn in damp weather. Air-cured tobacco should not carry the odor of smoke or fumes...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Air-cured. 29.6002 Section 29.6002 Agriculture... INSPECTION Standards Definitions § 29.6002 Air-cured. Tobacco cured under natural atmospheric conditions..., pole-burn, and shed-burn in damp weather. Air-cured tobacco should not carry the odor of smoke or fumes...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 2 2011-01-01 2011-01-01 false Air-cured. 29.6002 Section 29.6002 Agriculture... INSPECTION Standards Definitions § 29.6002 Air-cured. Tobacco cured under natural atmospheric conditions..., pole-burn, and shed-burn in damp weather. Air-cured tobacco should not carry the odor of smoke or fumes...
40 CFR 60.2820 - When must I complete each increment of progress?
Code of Federal Regulations, 2014 CFR
2014-07-01
... PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model Rule-Air Curtain...
2013-12-04
Table 3. Monthly PMCS Actions and Labor Required Task Hours Task Hours Inspect cab and hood 1.0 Inspect turbocharger 0.5 Inspect fuel tank 0.1 Inspect...Annual PMCS Actions and Labor Required Task Hours Task Hours Inspect cab and hood 1.0 Air intake system 0.2 Inspect fuel Tank 0.1 Inspect turbocharger
COPD Quiz | NIH MedlinePlus the Magazine
... irritant that causes COPD is: allergies cigarette smoke air pollution Question 4. Common signs and symptoms of COPD ... secondhand smoke avoid other lung irritants, such as air pollution, chemical fumes, and dust follow your treatment plan ...
29 CFR 1910.124 - General requirements for dipping and coating operations.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) Chemical reaction. (c) What requirements must I follow to recirculate exhaust air into the workplace? (1) You may not recirculate exhaust air when any substance in that air poses a health hazard to employees... Liquids. (5) When you use mechanical ventilation, it must draw the flow of air into a hood or exhaust duct...
Prezant, D; Malley, K; Barker, R; Guerth, C; Kelly, K
2001-01-01
Objectives—To determine (1) the effectiveness of hoods in reducing head burns, (2) the impact of clothes worn under the protective outer uniform (modern = long sleeve shirt and long pants; modified modern = short sleeve T-shirt and short pants) on burns, and (3) whether water content (dry, damp or saturated) affects the level of thermal protection. Setting—Fire Department of the City of New York (FDNY). Methods—Laboratory tests (fully dressed manikin) evaluated the different uniform and water conditions when exposed to an average 24 cal/cm2 heat flux, approximately 2250°F air temperature. FDNY field results compared (1) head burns during winters wearing the hood to winters without hood and (2) upper and lower extremity burns during summers wearing traditional, modern, and modified modern uniforms. Results—Laboratory tests showed that thermal protection was: (1) dramatically improved by the hood with protection increasing as water content increased and (2) not significantly different between modern and modified modern uniforms, regardless of water content. FDNY field results confirmed these tests showing (1) significant decreases in neck burns (by 54%), ear burns (by 60%), and head burn totals (by 46%) wearing the hood and (2) no significant differences in upper or lower extremity burns wearing modern compared with modified modern uniforms. Conclusions—Based on combined laboratory and field results, we strongly recommend the use of modern thermal protective hoods and the modified modern uniform. PMID:11565971
40 CFR 60.2835 - What if I do not meet an increment of progress?
Code of Federal Regulations, 2014 CFR
2014-07-01
... PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model Rule-Air Curtain...
On the Uses of Full-Scale Schlieren Flow Visualization
NASA Astrophysics Data System (ADS)
Settles, G. S.; Miller, J. D.; Dodson-Dreibelbis, L. J.
2000-11-01
A lens-and-grid-type schlieren system using a very large grid as a light source was described at earlier APS/DFD meetings. With a field-of-view of 2.3x2.9 m (7.5x9.5 feet), it is the largest indoor schlieren system in the world. Still and video examples of several full-scale airflows and heat-transfer problems visualized thus far will be shown. These include: heating and ventilation airflows, flows due to appliances and equipment, the thermal plumes of people, the aerodynamics of an explosive trace detection portal, gas leak detection, shock wave motion associated with aviation security problems, and heat transfer from live crops. Planned future projects include visualizing fume-hood and grocery display freezer airflows and studying the dispersion of insect repellent plumes at full scale.
40 CFR 81.219 - Central Oregon Intrastate Air Quality Control Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Central Oregon Intrastate Air Quality... Quality Control Regions § 81.219 Central Oregon Intrastate Air Quality Control Region. The Central Oregon... outermost boundaries of the area so delimited): In the State of Oregon: Crook County, Deschutes County, Hood...
40 CFR 81.219 - Central Oregon Intrastate Air Quality Control Region.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 18 2013-07-01 2013-07-01 false Central Oregon Intrastate Air Quality... Quality Control Regions § 81.219 Central Oregon Intrastate Air Quality Control Region. The Central Oregon... outermost boundaries of the area so delimited): In the State of Oregon: Crook County, Deschutes County, Hood...
40 CFR 81.219 - Central Oregon Intrastate Air Quality Control Region.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 18 2012-07-01 2012-07-01 false Central Oregon Intrastate Air Quality... Quality Control Regions § 81.219 Central Oregon Intrastate Air Quality Control Region. The Central Oregon... outermost boundaries of the area so delimited): In the State of Oregon: Crook County, Deschutes County, Hood...
40 CFR 81.219 - Central Oregon Intrastate Air Quality Control Region.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 18 2014-07-01 2014-07-01 false Central Oregon Intrastate Air Quality... Quality Control Regions § 81.219 Central Oregon Intrastate Air Quality Control Region. The Central Oregon... outermost boundaries of the area so delimited): In the State of Oregon: Crook County, Deschutes County, Hood...
40 CFR 81.219 - Central Oregon Intrastate Air Quality Control Region.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Central Oregon Intrastate Air Quality... Quality Control Regions § 81.219 Central Oregon Intrastate Air Quality Control Region. The Central Oregon... outermost boundaries of the area so delimited): In the State of Oregon: Crook County, Deschutes County, Hood...
40 CFR 721.10411 - Alkanenitrile, bis(cyanoalkyl)amino (generic) (P-07-537).
Code of Federal Regulations, 2012 CFR
2012-07-01
... with N100 (if oil aerosols absent), R100, or P100 filters; NIOSH-certified powered air-purifying respirator equipped with a loose- fitting hood or helmet and high efficiency particulate air (HEPA) filters... HEPA filters; or NIOSH-certified supplied-air respirator operated in pressure demand or continuous flow...
40 CFR 721.10411 - Alkanenitrile, bis(cyanoalkyl)amino (generic) (P-07-537).
Code of Federal Regulations, 2013 CFR
2013-07-01
... with N100 (if oil aerosols absent), R100, or P100 filters; NIOSH-certified powered air-purifying respirator equipped with a loose- fitting hood or helmet and high efficiency particulate air (HEPA) filters... HEPA filters; or NIOSH-certified supplied-air respirator operated in pressure demand or continuous flow...
40 CFR 721.10411 - Alkanenitrile, bis(cyanoalkyl)amino (generic) (P-07-537).
Code of Federal Regulations, 2014 CFR
2014-07-01
... with N100 (if oil aerosols absent), R100, or P100 filters; NIOSH-certified powered air-purifying respirator equipped with a loose- fitting hood or helmet and high efficiency particulate air (HEPA) filters... HEPA filters; or NIOSH-certified supplied-air respirator operated in pressure demand or continuous flow...
Bertram, Jens; Brand, Peter; Schettgen, Thomas; Lenz, Klaus; Purrio, Ellwyn; Reisgen, Uwe; Kraus, Thomas
2015-05-01
The uptake and elimination of metals from welding fumes is currently not fully understood. In the Aachen Workplace Simulation Laboratory (AWSL) it is possible to investigate the impact of welding fumes on human subjects under controlled exposure conditions. In this study, the uptake and elimination of chromium or chromium (VI) respectively as well as nickel was studied in subjects after exposure to the emissions of a manual metal arc welding process using low or high alloyed steel. In this present study 12 healthy male non-smokers, who never worked as welders before, were exposed for 6h to welding fumes of a manual metal arc welding process. In a three-fold crossover study design, subjects were exposed in randomized order to either clean air, emissions from welding low alloyed steel, and emissions from welding high alloyed steel. Particle mass concentration of the exposure aerosol was 2.5mg m(-3). The content of chromium and nickel in the air was determined by analysing air filter samples on a high emission scenario. Urine analysis for chromium and nickel was performed before and after exposure using methods of human biomonitoring. There were significantly elevated chromium levels after exposure to welding fumes from high alloyed steel compared to urinary chromium levels before exposure to high alloyed welding fumes, as well as compared to the other exposure scenarios. The mean values increased from 0.27 µg l(-1) to 18.62 µg l(-1). The results were in good agreement with already existing correlations between external and internal exposure (German exposure equivalent for carcinogenic working materials EKA). The variability of urinary chromium levels was high. For urinary nickel no significant changes could be detected at all. Six-hour exposure to 2.5mg m(-3) high alloyed manual metal arc welding fumes lead to elevated urinary chromium levels far higher (7.11-34.16 µg l(-1)) than the German biological exposure reference value (BAR) of 0.6 µg l(-1) directly after exposure. On the other hand mean urinary nickel concentrations slightly increased, but did not exceed background levels due to lower bioavailability. We could underline with our single exposure experiment that a welding work related chromium exposure can be measured immediately after the work shift, while the same is not possible for nickel exposure due to lower nickel bioavailability. The data provide useful information for real occupational welding work places. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
40 CFR 63.1159 - Operational and equipment standards for existing, new, or reconstructed sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... atmosphere shall be equipped with a local fume capture system, ventilated through an air pollution control... pollution control equipment and monitoring equipment in a manner consistent with safety and good air... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS...
40 CFR 63.1159 - Operational and equipment standards for existing, new, or reconstructed sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... atmosphere shall be equipped with a local fume capture system, ventilated through an air pollution control... pollution control equipment and monitoring equipment in a manner consistent with safety and good air... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS...
40 CFR 63.341 - Definitions and nomenclature.
Code of Federal Regulations, 2011 CFR
2011-07-01
... given in this section. Add-on air pollution control device means equipment installed in the ventilation... chromium emissions from the tank(s). Air pollution control technique means any method, such as an add-on air pollution control device or a chemical fume suppressant, that is used to reduce chromium emissions...
40 CFR 60.2805 - Am I required to apply for and obtain a Title V operating permit for my unit?
Code of Federal Regulations, 2013 CFR
2013-07-01
... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model... permit for my unit? Yes. Each CISWI unit and air curtain incinerator subject to standards under this...
40 CFR 60.2805 - Am I required to apply for and obtain a Title V operating permit for my unit?
Code of Federal Regulations, 2014 CFR
2014-07-01
... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration Units Model... permit for my unit? Yes. Each CISWI unit and air curtain incinerator subject to standards under this...
Effect of Various Parameters on Evolution of 2D Free Jets and their Associated Entrainment Rates
NASA Astrophysics Data System (ADS)
Amin, Mazyar; Dabiri, Dana; Navaz, Homayun
2006-11-01
Refrigerated vertical display cases are extensively used in supermarkets and grocery stores. Cold air is supplied vertically across the open face of the display case from the top, creating a cold air curtain acting as a barrier to separate the cold air within the case from the warm ambient air. Typically, 70-80% of the load on these vertical display cases is due to cooling of infiltrated warm ambient air. Our goal is to understand parameters affecting warm air infiltration into the case so as to minimize the cooling load. Towards this end, steady state behavior of 2D vertical air jets at Reynolds numbers 2,000 to 10,000 with low and high turbulence intensities (0% &10%) at the nozzle exit are experimentally and computationally investigated both within a quiescent ambient and next to an open cavity. Four different velocity profile shapes (top-hat, parabola, skewed parabola and linear) at the jet exit are also studied to determine profile effects on the evolution of and entrainment into the jet. Results will be presented to show the effect of these parameters on the total entrainment into the jet, as well as the variation of entrainment across the jet at different downstream locations. The results of this work can help better understand how to design air curtains as a buffer to minimize infiltration into open refrigerated vertical display cases.
Air Quality and Respiratory Health among Adolescents from the United Arab Emirates
Dghaim, Rania
2015-01-01
Purpose. To examine the role of air quality in relation to chronic bronchitis, emphysema, asthma, wheeze, and dry cough among adolescents from the United Arab Emirates (UAE). Methods. A survey was administered on 6,363 adolescents from 9 UAE regions. Data consists of demographic, socioeconomic, residential, and behavioural variables, such as location of residence, residing near industry/gas stations/dumpsites/construction sites, residing near overhead power line/plants, exposure to tobacco, residential exposure, ethnicity, concern over air pollution, smoking, and purposely smelling gasoline fumes/glue/correctors/car exhaust/burning black ants. Logistic regression modeling was used to determine significant predictors of respiratory health. Results. Asthma prevalence was 12.3%, followed by chronic bronchitis (1.8%) and emphysema (0.5%). Overall 12.2% reported wheeze and 34.8% reported a dry nocturnal cough in the past year. Multivariate analyses suggest that sex is a significant predictor of asthma and dry cough. Exposure to tobacco and arts/crafts/ceramics/stain is significant predictor of respiratory health. Tobacco smoking and purposely smelling gasoline fumes/glue/correctors/car exhaust/burning black ants are significant predictors of wheeze and dry cough. Conclusions. This study suggests that exposure to air quality and behavioral factors such as smoking and purposely smelling gasoline fumes, glue, correctors, car exhaust, or burning black ants are significant predictors of respiratory health among UAE adolescents. PMID:26074980
CFD gas distribution analysis for different continuous-miner scrubber redirection configurations
Zheng, Y.; Organiscak, J.A.; Zhou, L.; Beck, T.W.; Rider, J.P.
2018-01-01
The U.S. National Institute for Occupational Safety and Health (NIOSH)’s Pittsburgh Mining Research Division (PMRD) recently developed a series of models using computational fluid dynamics (CFD) to study gas distribution around a continuous mining machine with various fan-powered flooded bed scrubber discharge configurations in an exhaust curtain working face. CFD models utilizing species transport model without reactions in FLUENT were constructed to evaluate the redirection of scrubber discharge toward the mining face rather than behind the return curtain. The study illustrates the gas distribution in the slab (second) cut. The following scenarios are considered in this study: 100 percent of the discharge redirected back toward the face on the off-curtain side; 100 percent of the discharge redirected back toward the face, but divided equally to both sides; and 15 percent of the discharge redirected toward the face on the off-curtain side, with 85 percent directed toward the return curtain. These models are compared against a model with a conventional scrubber discharge where air is directed away from the face into the return. The models were validated against experimental data, proving to accurately predict sulfur hexafluoride (SF6) gas levels at four gas monitoring locations. This study includes a predictive simulation examining a 45° scrubber angle compared with the 23° angle for the 100 percent redirected, equally divided case. This paper describes the validation of the CFD models based on experimental data of the gas distribution results. PMID:29375242
CFD gas distribution analysis for different continuous-miner scrubber redirection configurations.
Zheng, Y; Organiscak, J A; Zhou, L; Beck, T W; Rider, J P
2017-01-01
The U.S. National Institute for Occupational Safety and Health (NIOSH)'s Pittsburgh Mining Research Division (PMRD) recently developed a series of models using computational fluid dynamics (CFD) to study gas distribution around a continuous mining machine with various fan-powered flooded bed scrubber discharge configurations in an exhaust curtain working face. CFD models utilizing species transport model without reactions in FLUENT were constructed to evaluate the redirection of scrubber discharge toward the mining face rather than behind the return curtain. The study illustrates the gas distribution in the slab (second) cut. The following scenarios are considered in this study: 100 percent of the discharge redirected back toward the face on the off-curtain side; 100 percent of the discharge redirected back toward the face, but divided equally to both sides; and 15 percent of the discharge redirected toward the face on the off-curtain side, with 85 percent directed toward the return curtain. These models are compared against a model with a conventional scrubber discharge where air is directed away from the face into the return. The models were validated against experimental data, proving to accurately predict sulfur hexafluoride (SF 6 ) gas levels at four gas monitoring locations. This study includes a predictive simulation examining a 45° scrubber angle compared with the 23° angle for the 100 percent redirected, equally divided case. This paper describes the validation of the CFD models based on experimental data of the gas distribution results.
Li, Yu-Hua; Cheng, Su-Wen; Yuan, Chung-Shin; Lai, Tzu-Fan; Hung, Chung-Hsuang
2018-06-05
Chinese cooking fume is one of the sources of volatile organic compounds (VOCs) in the air. An innovative control technology combining photocatalytic degradation and ozone oxidation (UV/TiO 2 +O 3 ) was developed to decompose VOCs in the cooking fume. Fiberglass filter (FGF) coated with TiO 2 was prepared by an impregnation procedure. A continuous-flow reaction system was self-designed by combining photocatalysis with advanced ozone oxidation technique. By passing the simulated cooking fume through the FGF, the VOC decomposition efficiency in the cooking fume could be increased by about 10%. The decomposition efficiency of VOCs in the cooking fume increased and then decreased with the inlet VOC concentration. A maximum VOC decomposition efficiency of 64% was obtained at 100 ppm. Similar trend was observed for reaction temperature with the VOC decomposition efficiencies ranging from 64 to 68%. Moreover, inlet ozone concentration had a positive effect on the decomposition of VOCs in the cooking fume for inlet ozone≤1000 ppm and leveled off for inlet ozone>1000 ppm. 34% of VOC decomposition efficiency was achieved solely by ozone oxidation with or without near-UV irradiation. A maximum of 75% and 94% VOC decomposition efficiency could be achieved by O 3 +UV/TiO 2 and UV/TiO 2 +O 3 techniques, respectively. The maximum decomposition efficiencies of VOCs decreased to 79% for using UV/TiO 2 +O 3 technique with adding water in the oil fume. Comparing the chromatographical species of VOCs in the oil fume before and after the decomposition of VOCs by using UV/TiO 2 +O 3 technique, we found that both TVOC and VOC species in the oil fume were effectively decomposed. Copyright © 2018 Elsevier Ltd. All rights reserved.
Rim, Donghyun; Wallace, Lance; Nabinger, Steven; Persily, Andrew
2012-08-15
Cooking stoves, both gas and electric, are one of the strongest and most common sources of ultrafine particles (UFP) in homes. UFP have been shown to be associated with adverse health effects such as DNA damage and respiratory and cardiovascular diseases. This study investigates the effectiveness of kitchen exhaust hoods in reducing indoor levels of UFP emitted from a gas stove and oven. Measurements in an unoccupied manufactured house monitored size-resolved UFP (2 nm to 100 nm) concentrations from the gas stove and oven while varying range hood flow rate and burner position. The air change rate in the building was measured continuously based on the decay of a tracer gas (sulfur hexafluoride, SF(6)). The results show that range hood flow rate and burner position (front vs. rear) can have strong effects on the reduction of indoor levels of UFP released from the stove and oven, subsequently reducing occupant exposure to UFP. Higher range hood flow rates are generally more effective for UFP reduction, though the reduction varies with particle diameter. The influence of the range hood exhaust is larger for the back burner than for the front burner. The number-weighted particle reductions for range hood flow rates varying between 100 m(3)/h and 680 m(3)/h range from 31% to 94% for the front burner, from 54% to 98% for the back burner, and from 39% to 96% for the oven. Copyright © 2012 Elsevier B.V. All rights reserved.
Energy-Conscious Design. Part 1.
ERIC Educational Resources Information Center
Lawrence, Jerry
1984-01-01
Practical energy-design elements adaptable for schools include building orientation and shape, inclusion of an energy-storage system, window placement, double or triple window glazing, air-curtain windows, and the use of earth berms and trees as wind breaks. (MLF)
40 CFR 60.2245 - What is an air curtain incinerator?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Industrial Solid Waste Incineration Units for Which Construction Is Commenced After November 30, 1999 or for....2260). (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent mixture of only wood...
40 CFR 60.56b - Standards for air curtain incinerators.
Code of Federal Regulations, 2010 CFR
2010-07-01
... fuel feed stream composed of 100 percent yard waste and no other municipal solid waste materials shall...-minute average) is permitted during startup periods during the first 30 minutes of operation of the unit...
Effects on the efficiency of activated carbon on exposure to welding fumes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghosh, D.
1995-02-01
It is the intention of this paper to document that certain types of welding fumes have little or no effect on the effectiveness of the carbon filter air filtration efficiency when directly exposed to a controlled amount of welding fumes for a short-term period. The welding processes studied were restricted to shielded metal arc welding (SMAW), flux cored arc welding (FCAW), gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) processes. Contrary to the SMAW and FCAW processes, the GTAW (or TIG) and the GMAW (or MIG) welding processes do not require the use of flux as partmore » of the overall process. Credit was taken for these processes occurring in inert gas environments and producing minimal amount of smoke. It was concluded that a study involving the SMAW process would also envelop the effects of the TIG and MIG welding processes. The quantity of welding fumes generated during the arc welding process is a function of the particular process, the size and type of electrode, welding machine amperage, and operator proficiency. For this study, the amount of welding for specific testing was equated to the amount of welding normally conducted during plant unit outages. Different welding electrodes were also evaluated, and the subsequent testing was limited to an E7018 electrode which was judged to be representative of all carbon and stainless steel electrodes commonly used at the site. The effect of welding fumes on activated charcoal was tested using a filtration unit complete with prefilters, upstream and downstream high efficiency particulate air (HEPA) filters, and a carbon adsorber section. The complete system was field tested in accordance with ANSI N510 standards prior to exposing the filters and the adsorber bed to welding fumes. The carbon samples were tested at an established laboratory using ASTM D3803-1989 standards.« less
[Determination of fumes and their elements from flux cored arc welding].
Matczak, Wanda; Przybylska-Stanisławska, Magdalena
2004-01-01
The aim of this work was to assay the concentration levels and composition of welding fumes, released during flux cored arc welding, to assess exposure of welders. Concentrations and welding fume components, such as iron, manganese, chromium (including the soluble and chromium VI), nickel, copper, calcium, aluminium, barium, and fluorides (including hydrogen fluoride) were determined in the air of six industrial plants (shipyards, mechanical engineering plants and a power station) at the breathing zones of the welders who used 10 types of wires during flux cored arc welding. The following determination methods were used: gravimetry (fumes), AAS (metals), and spectrophotometry (chromium VI, fluorides--including hydrogen fluoride). The results made it possible to determine the relationship between concentrations of welding fume and its elements, and to assess worker's exposure. Time weighted average concentrations of the welding fumes and its elements at the worker's breathing zone were: mg/m3: dust 0.2-24.3; Fe 0.2-6.7; Mn 0.01-1.8; Cr 0.004-0.5 (mainly Cr III); Ca 0.004-2.5; Ni < or = 0.004; Cu < 0.002-0.05; Al < 0.14-0.4; Ba < 0.14; F- 0.07-0.43. The welders using some types of flux cored welding wires worked in conditions harmful to their health owing to the considerably exceeded TLV value for fume and MAC values for manganese, and occasional slightly excessive MAC values for calcium and iron.
1993-12-01
Evaluation of Increased Payloads 6 3.2 Microencapsulation Scale-up of Pilot DNBM 10 4 SURFACE TREATMENT OF MICROCAPSULES 11 4.1 Fumed Silica Additions to... Microencapsulated DNBM b. Fumed-Silica Mixed Microcapsules C. Solvent-Extracted Silanized Microcapsules Fig. 8 SEM Photomicrographs of Pilot-DNBM... Microcapsules 18 NAWCADWAR-94128-60 Section 5 FORMULATION AND TEST OF 100% DNBM AND MICROENCAPSULATED DNBM IN EPOXY-POLYAMIDE PRIMER At the start of the
18. VIEW OF EAST SIDE INTERIOR OF MST AT STATIONS ...
18. VIEW OF EAST SIDE INTERIOR OF MST AT STATIONS 3 AND 12, FACING WEST. COMPRESSED AIR TANK AND GENERATOR AT STATION 3. CURTAIN FOR NORTH ENVIRONMENTAL DOOR VISIBLE ON LEFT SIDE OF PHOTOGRAPH; RAIL VISIBLE AT BOTTOM OF PHOTOGRAPH. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA
This report is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not present and should not be construted to represent any Agency determination or policy. M...
40 CFR 62.14107 - Emission limits for air curtain incinerators.
Code of Federal Regulations, 2010 CFR
2010-07-01
... and that combusts a fuel feed stream composed of 100 percent yard waste and no other municipal solid... level of up to 35 percent (6-minute average) is permitted during startup periods during the first 30...
NPF MECHANICAL CELL NaK DISPOSAL AND FUME ABATEMENT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rey, G.
Some of the fuels originally scheduled for processing in the nonproduction fuel (NPF) processing program incorporated sodium or sodium- potassium alloy (NaK) as the bonding material between stainless-steel cladding and the uranium or uranium-molybdenum alloy core. Because of the special hazards involved in handling NaK, studies were made to determine safe methods for processing NaK-containing fuels. An underwater NaK dispensing system was installed, and tests were made to determine the characteristics of the NaK-water reaction. The equipment consisted of a dispenser, reaction pan, and off-gas scrubber. After initinl studies, a prototype test was made wherein U-Mo canned slugs containing NaKmore » reservoirs were hack sawed underwater. The studies demonstrated that the NaK reservoirs can be safely deactivated by hack sawing under a submerged hood in a shallow water bath. (W.L.H.)« less
Kilogram-scale prexasertib monolactate monohydrate synthesis under continuous-flow CGMP conditions.
Cole, Kevin P; Groh, Jennifer McClary; Johnson, Martin D; Burcham, Christopher L; Campbell, Bradley M; Diseroad, William D; Heller, Michael R; Howell, John R; Kallman, Neil J; Koenig, Thomas M; May, Scott A; Miller, Richard D; Mitchell, David; Myers, David P; Myers, Steven S; Phillips, Joseph L; Polster, Christopher S; White, Timothy D; Cashman, Jim; Hurley, Declan; Moylan, Robert; Sheehan, Paul; Spencer, Richard D; Desmond, Kenneth; Desmond, Paul; Gowran, Olivia
2017-06-16
Advances in drug potency and tailored therapeutics are promoting pharmaceutical manufacturing to transition from a traditional batch paradigm to more flexible continuous processing. Here we report the development of a multistep continuous-flow CGMP (current good manufacturing practices) process that produced 24 kilograms of prexasertib monolactate monohydrate suitable for use in human clinical trials. Eight continuous unit operations were conducted to produce the target at roughly 3 kilograms per day using small continuous reactors, extractors, evaporators, crystallizers, and filters in laboratory fume hoods. Success was enabled by advances in chemistry, engineering, analytical science, process modeling, and equipment design. Substantial technical and business drivers were identified, which merited the continuous process. The continuous process afforded improved performance and safety relative to batch processes and also improved containment of a highly potent compound. Copyright © 2017, American Association for the Advancement of Science.
A Mass Spectrometer in Every Fume Hood
NASA Astrophysics Data System (ADS)
McBride, Ethan M.; Verbeck, Guido F.
2018-06-01
Since their inception, mass spectrometers have played a pivotal role in the direction and application of synthetic chemical research. The ability to develop new instrumentation to solve current analytical challenges in this area has always been at the heart of mass spectrometry, although progress has been slow at times. Herein, we briefly review the history of how mass spectrometry has been used to approach challenges in organic chemistry, how new developments in portable instrumentation and ambient ionization have been used to open novel areas of research, and how current techniques have the ability to expand on our knowledge of synthetic mechanisms and kinetics. Lastly, we discuss the relative paucity of work done in recent years to embrace the concept of improving benchtop synthetic chemistry with mass spectrometry, the disconnect between applications and fundamentals within these studies, and what hurdles still need to be overcome. [Figure not available: see fulltext.
NASA Astrophysics Data System (ADS)
Jiang, Zheng; Kong, Liang; Alenazey, Feraih Sh.; Qian, Yangdong; France, Liam; Xiao, Tiancun; Edwards, Peter P.
2013-05-01
A facile solvent evaporation induced self-assembly (SEISA) strategy was developed to synthesize mesoporous N-doped anatase TiO2 (SE-meso-TON) using a single organic complex precursor derived in situ from titanium butoxide and ethylenediamine in ethanol solution. After the evaporation of ethanol in a fume hood and subsequent calcinations at 450 °C, the obtained N-doped TiO2 (meso-TON) anatase was of finite crystallite size, developed porosity, large surface area (101 m2 g-1) and extended light absorption in the visible region. This SE-meso-TON also showed superior photocatalytic activity to the SG-meso-TON anatase prepared via sol-gel synthesis. On the basis of characterization results from XRD, XPS, N2 adsorption-desorption and ESR, the enhanced visible-light-responsive photocatalytic activity of SE-meso-TON was assigned to its developed mesoporosity and reduced oxygen vacancies.
Histological Study of the Toxic Effects of Solder Fumes on Spermatogenesis in Rats
Arab, Mohammad Reza; Heidari, Mohammad Hossein; Mashhadi, Rezvaneh; Mirzaei, Ramazan; Jahantigh, Mehdi
2011-01-01
Objective: Toxic fumes generated during the soldering process contain various contaminants released at sufficient rates to cause both short- and long-term health problems. Studies have shown that these fumes change the quality and quantity of semen fluid in exposed workers. The aim of the present study was to determine the potentially toxic effects of solder fumes on spermatogenesis in seminiferous tubules of rats as an experimental model, with conditioned media in an exposed chamber. Materials and Methods: A total number of 48 male Sprague Dawley adult rats were randomly divided into experimental (n=30) and control (n=18) groups. Based on exposure time, each group was further subdivided into two, four and six subgroups. Rats in the experimental groups were exposed to solder fumes in an exposure chamber for one hour/ day. The concentrations of fumes [formaldehyde, stanum (Sn) and lead (Pb)] were measured by a standard method via atomic absorption and spectrophotometry. According to a timetable, under deep anesthesia, the rats of both experimental and control subgroups were killed. After fixation of testes, specimens were weighed and routinely processed. Paraffin sections were stained by hematoxylin and eosin. Spermiogenesis index was calculated and data analyzed by Mann Whitney NPAR test. Results: Analysis of air samples in the exposure chamber showed the following fume concentrations: 0.193 mg/m3 for formaldehyde, 0.35 mg/m3 for Sn and 3 mg/m3 for Pb. Although there was no significant difference in testes weight between control and experimental subgroups, there was only a significant difference in spermiogenesis index between the six week experimental and control subgroups (p<0.02). Conclusion: The results of this study showed that solder fumes can change the spermiogenesis index in experimental groups in a time dependent manner. PMID:23671821
40. VIEW LOOKING IN TANK JUST OUTSIDE DOOR TO AIR ...
40. VIEW LOOKING IN TANK JUST OUTSIDE DOOR TO AIR LOCK. HIGH HOOKS IS POSITIONING THE STEINKE HOOD ON THE TRAINEE, WHILE LOW HOOKS HOLDS HIM IN PLACE No date - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT
Butler, Owen; Musgrove, Darren; Stacey, Peter
2014-01-01
Workers can be exposed to fume, arising from welding activities, which contain toxic metals and metalloids. Occupational hygienists need to assess and ultimately minimize such exposure risks. The monitoring of the concentration of particles in workplace air is one assessment approach whereby fume, from representative welding activities, is sampled onto a filter and returned to a laboratory for analysis. Inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry are generally employed as instrumental techniques of choice for the analysis of such filter samples. An inherent difficulty, however, with inductively coupled plasma-based analytical techniques is that they typically require a sample to be presented for analysis in the form of a solution. The efficiency of the required dissolution step relies heavily upon the skill and experience of the analyst involved. A useful tool in assessing the efficacy of this dissolution step would be the availability and subsequent analysis of welding fume reference materials with stated elemental concentrations and matrices that match as closely as possible the matrix composition of welding fume samples submitted to laboratories for analysis. This article describes work undertaken at the Health and Safety Laboratory to prepare and certify two new bulk welding fume reference materials that can be routinely used by analysts to assess the performance of the digestion procedures they employ in their laboratories. PMID:24499055
Butler, Owen; Musgrove, Darren; Stacey, Peter
2014-01-01
Workers can be exposed to fume, arising from welding activities, which contain toxic metals and metalloids. Occupational hygienists need to assess and ultimately minimize such exposure risks. The monitoring of the concentration of particles in workplace air is one assessment approach whereby fume, from representative welding activities, is sampled onto a filter and returned to a laboratory for analysis. Inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry are generally employed as instrumental techniques of choice for the analysis of such filter samples. An inherent difficulty, however, with inductively coupled plasma-based analytical techniques is that they typically require a sample to be presented for analysis in the form of a solution. The efficiency of the required dissolution step relies heavily upon the skill and experience of the analyst involved. A useful tool in assessing the efficacy of this dissolution step would be the availability and subsequent analysis of welding fume reference materials with stated elemental concentrations and matrices that match as closely as possible the matrix composition of welding fume samples submitted to laboratories for analysis. This article describes work undertaken at the Health and Safety Laboratory to prepare and certify two new bulk welding fume reference materials that can be routinely used by analysts to assess the performance of the digestion procedures they employ in their laboratories.
40 CFR 721.10575 - 1-Propanone, 1,1'-(oxydi-4,1-phenylene)bis[2-hydroxy-2-methyl-.
Code of Federal Regulations, 2013 CFR
2013-07-01
...), R100, or P100 filters. (B) NIOSH-certified air-purifying, tight-fitting full-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters...
40 CFR 721.10575 - 1-Propanone, 1,1'-(oxydi-4,1-phenylene)bis[2-hydroxy-2-methyl-.
Code of Federal Regulations, 2014 CFR
2014-07-01
...), R100, or P100 filters. (B) NIOSH-certified air-purifying, tight-fitting full-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters...
Ma, Jane Y C; Rengasamy, Apavoo; Frazer, Dave; Barger, Mark W; Hubbs, Ann F; Battelli, Lori; Tomblyn, Seith; Stone, Samuel; Castranova, Vince
2003-01-01
Asphalt fumes are complex mixtures of various organic compounds, including polycyclic aromatic hydrocarbons (PAHs). PAHs require bioactivation by the cytochrome P-450 monooxygenase system to exert toxic/carcinogenic effects. The present study was carried out to characterize the acute pulmonary inflammatory responses and the alterations of pulmonary xenobiotic pathways in rats exposed to asphalt fumes by inhalation. Rats were exposed at various doses and time periods to air or to asphalt fumes generated at paving temperatures. To assess the acute damage and inflammatory responses, differential cell counts, acellular lactate dehydrogenase (LDH) activity, and protein content of bronchoalveolar lavage fluid were determined. Alveolar macrophage (AM) function was assessed by monitoring generation of chemiluminescence and production of tumor necrosis factor-alpha and interleukin-1. Alteration of pulmonary xenobiotic pathways was determined by monitoring the protein levels and activities of P-450 isozymes (CYP1A1 and CYP2B1), glutathioneS-transferase (GST), and NADPH:quinone oxidoreductase (QR). The results show that acute asphalt fume exposure did not cause neutrophil infiltration, alter LDH activity or protein content, or affect AM function, suggesting that short-term asphalt fume exposure did not induce acute lung damage or inflammation. However, acute asphalt fume exposure significantly increased the activity and protein level of CYP1A1 whereas it markedly reduced the activity and protein level of CYP2B1 in the lung. The induction of CYP1A1 was localized in nonciliated bronchiolar epithelial (Clara) cells, alveolar septa, and endothelial cells by immunofluorescence microscopy. Cytosolic QR activity was significantly elevated after asphalt fume exposure, whereas GST activity was not affected by the exposure. This induction of CYP1A1 and QR with the concomitant down-regulation of CYP2B1 after asphalt fume exposure could alter PAH metabolism and may lead to potential toxic effects in the lung. PMID:12842776
Chen, Jia-Kun; Huang, Rong Fung; Peng, Kuan-Lin
2012-01-01
The effects of draft on the flow and spillage characteristics of wall-mounted and jet-isolated range hoods were investigated. A specially designed draft generator that could supply low-swirl air current was used to provide "cross draft" from three directions, lateral (θ = 0(o)), oblique (θ = 45(o)), and front (θ = 90(o)), with respect to the center point of the range hoods. Flow characteristics of oil mist were inspected through visualization of smoke flows with light scattering (laser light sheet-assisted visualization of smoke flow). The leakage mechanisms, which were closely related to the flow features, were studied by examining both movies and still pictures showing smoke-flow evolution. The sulfur hexafluoride tracer gas concentration detection method was employed to measure the capture indices. The results showed that the lateral draft pushed the pollutants generated under the hood in the opposite direction and induced serious spillage. The oblique draft pushed the pollutants toward both the rear wall and opposite side and induced more serious spillage than did the lateral draft. The frontal draft forced the pollutants to bifurcate into streams moving toward the left and the right, and induced the most serious pollutant spillage among the three tested drafts. Pollutant spillage became critically significant as the cross draft velocity was increased to greater than 0.2 m/sec. Spillage of pollutants increased as the velocity of the cross draft was increased. Increasing the suction flow rate of the range hood may increase resistance to the draft, but the benefits were limited at draft velocities greater than 0.2 m/sec. Both range hoods had a similarly low capture index under the influence of the lateral draft. For the oblique and frontal drafts, the jet-isolated range hood demonstrated a higher capture index than did the wall-mounted range hood.
40 CFR 60.2830 - When must I submit the notifications of achievement of increments of progress?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Commenced Construction On or Before November 30, 1999 Model Rule-Air Curtain Incinerators § 60.2830 When... increments of progress must be postmarked no later than 10 business days after the compliance date for the...
2014 Texas Military Value Task Force: Preparing for the Future
2014-01-01
Mayor Bob Bruggeman, City of Texarkana 4. Naval Air Station Fort Worth Joint Reserve Base, City of Fort Worth 5. Dyess Air Force Base, Mayor Norm...Ellington Field): Composite – 98.2 Killeen (Fort Hood): Composite – 85.0 San Antonio (JBSA): Composite – 92.5 Texarkana (RRAD): Composite – 94.6 Wichita
Evaluation of occupational exposure to toxic metals released in the process of aluminum welding.
Matczak, Wanda; Gromiec, Jan
2002-04-01
The objective of this study was to evaluate occupational exposure to welding fumes and its elements on aluminum welders in Polish industry. The study included 52 MIG/Al fume samples and 18 TIG/Al samples in 3 plants. Air samples were collected in the breathing zone of welders (total and respirable dust). Dust concentration was determined gravimetrically, and the elements in the collected dust were determined by AAS. Mean time-weighted average (TWA) concentrations of the welding dusts/fumes and their components in the breathing zone obtained for different welding processes were, in mg/m3: MIG/Al fumes mean 6.0 (0.8-17.8), Al 2.1 (0.1-7.7), Mg 0.2 (< 0.1-0.9), Mn 0.014 (0.002-0.049), Cu 0.011 (0.002-0.092), Zn 0.016 (0.002-0.14), Pb 0.009 (0.005-0.025), Cr 0.003 (0.002-0.007), and TIG/Al fumes 0.7 (0.3-1.4), Al 0.17 (0.07-0.50). A correlation has been found between the concentration of the main components and the fume/dust concentrations in MIG/Al and TIG/Al fumes. Mean percentages of the individual components in MIG/Al fumes/dusts were Al: 30 (9-56) percent; Mg: 3 (1-5.6) percent; Mn: 0.2 (0.1-0.3) percent; Cu: 0.2 (< 0.1-1.8) percent; Zn: 0.2 (< 0.1-0.8) percent; Pb: 0.2 (< 0.1-1) percent; Cr: < 0.1 percent. The proportion of the respirable fraction in the fumes and their constituents varied between 10 percent and 100 percent. The results showed that MIG/Al fumes concentration was 1.2 times higher than the American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit value (TLV), and the index of the combined exposure to the determined agents was 2.3 (0.4-8.0), mostly because of high Al2O3 contribution. The background concentrations of the components (ca. 5-10 times lower than those in the breathing zone of the welders) did not exceed the Polish MAC value. The elemental composition of total and respirable fume/dust may differ considerably depending on welding methods, the nature of welding-related operations, and work environment conditions.
... bronchial tubes produce a lot of mucus. This leads to coughing and difficulty breathing. Cigarette smoking is the most common cause. Breathing in air pollution, fumes, or dust over a long period of ...
Ellingsen, Dag G; Dubeikovskaya, Larisa; Dahl, Kari; Chashchin, Maxim; Chashchin, Valery; Zibarev, Evgeny; Thomassen, Yngvar
2006-10-01
In a cross-sectional study, 96 welders were compared with 96 control subjects. Also 27 former welders, all diagnosed as having manganism, were examined. Exposure to welding fumes was determined in the 96 welders, while the concentration of elements in whole blood and urine was determined in all subjects. The geometric mean (GM) concentrations of manganese (Mn) and iron in the workroom air were 97 microg m(-3) (range 3-4620 microg m(-3); n=188) and 894 microg m(-3) (range 106-20 300 microg m(-3); n=188), respectively. Thus the Mn concentration in the workroom air was on average 10.6% (GM) of that of the Fe concentration. No substantial difference was observed in the air Mn concentrations when welding mild steel as compared to welding stainless steel. The arithmetic mean (AM) concentration of Mn in whole blood (B-Mn) was about 25% higher in the welders compared to the controls (8.6 vs. 6.9 microg l(-1); p < 0.001), while the difference in the urinary Mn concentrations did not attain statistical significance. A Pearson's correlation coefficient of 0.31 (p < 0.01) was calculated between B-Mn and Mn in the workroom air that was collected the day before blood sampling. Although the exposure to welding fumes in the patients had ceased on average 5.8 years prior to the study (range 4 years-7 years), their AM B-Mn concentration was still higher than in referents of similar age (8.7 microg l(-1) vs. 7.0 microg l(-1)). However, their urinary concentrations of cobolt, iron and Mn were all statistically significantly lower.
Disinsection: evolution of the air curtain in the last year
USDA-ARS?s Scientific Manuscript database
Certain countries require disinsection of commercial aircraft from overseas flights before passengers and crews disembark. Currently acceptable method: spray aircraft interior with pesticides. One of the problems with this is that passengers and crew are exposed to pesticides. There are pesticide se...
40 CFR 60.2835 - What if I do not meet an increment of progress?
Code of Federal Regulations, 2010 CFR
2010-07-01
... or Before November 30, 1999 Model Rule-Air Curtain Incinerators § 60.2835 What if I do not meet an... Administrator postmarked within 10 business days after the date for that increment of progress in table 1 of...
Medical Experts and Agnotology in the Fumes Controversy of the Huelva Copper Mines (1888–1890)
Guillem-Llobat, Ximo
2017-01-01
Huelva’s copper mines (Spain) have been active for centuries but in the second half of the nineteenth century extractive activities in Riotinto, Tharsis, and other mines in the region were intensified in order to reach world leadership. The method used in these mines for copper extraction from low grade ores generated continuous emissions of fumes that were extremely controversial. The inhabitants had complained about the fumes for decades but as activity intensified so did complaints. The killing of anti-fumes demonstrators in 1888 led to the passing of a Royal Decree banning the open-air roasting of ore and to the drafting of numerous reports on the hazards of the fumes. Major state and provincial medical institutions, as well as renowned hygienists and engineers, took part in the assessment, contributing to a scientific controversy especially rich in content. In my paper I will analyse the production and circulation of knowledge and ignorance about the impact of fumes on public health, as well as the role of medical experts and expertise in the controversy. The analysis will focus on the reports drafted between the 1888 ban and its 1890 repeal, and will show the changing nature of the expert assessment and the numerous paths followed by experts in producing ignorance. The paper will conclude by considering other stakeholders, who may shed some light on the reasons behind the performance of the medical experts. PMID:28604295
Removal of Fluorides and Chlorides from Zinc Oxide Fumes by Microwave Sulfating Roasting
NASA Astrophysics Data System (ADS)
Li, Zhiqiang; Zhang, Libo; Chen, Guo; Peng, Jinhui; Zhou, Liexing; Yin, Shaohua; Liu, Chenhui
2015-10-01
Dechlorination and defluorination from zinc oxide dust by microwave sulfating roasting was investigated in this study. According to proposed reactions in the process, detailed experiments were systematically conducted to study the effect of roasting temperature, holding time, air and steam flow rates on the efficiency of the removal of F and Cl. The results show that 92.3% of F and 90.5% of Cl in the fume could be purified when the condition of the roasting temperature of 650 °C, holding time at 60 min, air flow of 300 L/h and steam flow of 8 ml/min was optimized. Our investigation indicates that microwave sulfating roasting could be a promising new way for the dechlorination and defluorination from zinc oxide dust.
Design and validation of a passive deposition sampler.
Einstein, Stephanie A; Yu, Chang-Ho; Mainelis, Gediminas; Chen, Lung Chi; Weisel, Clifford P; Lioy, Paul J
2012-09-01
A new, passive particle deposition air sampler, called the Einstein-Lioy Deposition Sampler (ELDS), has been developed to fill a gap in passive sampling for near-field particle emissions. The sampler can be configured in several ways: with a protective hood for outdoor sampling, without a protective hood, and as a dust plate. In addition, there is an XRF-ready option that allows for direct sampling onto a filter-mounted XRF cartridge which can be used in conjunction with all configurations. A wind tunnel was designed and constructed to test the performance of different sampler configurations using a test dust with a known particle size distribution. The sampler configurations were also tested versus each other to evaluate whether or not the protective hood would affect the collected particle size distribution. A field study was conducted to test the sampler under actual environmental conditions and to evaluate its ability to collect samples for chemical analysis. Individual experiments for each configuration demonstrated precision of the sampler. The field experiment demonstrated the ability of the sampler to both collect mass and allow for the measurement of an environmental contaminant i.e. Cr(6+). The ELDS was demonstrated to be statistically not different for Hooded and Non-Hooded models, compared to each other and the test dust; thus, it can be used indoors and outdoors in a variety of configurations to suit the user's needs.
Numerical investigation of turbulence in reshocked Richtmyer-Meshkov unstable curtain of dense gas
NASA Astrophysics Data System (ADS)
Shankar, S. K.; Lele, S. K.
2014-01-01
Moderate-resolution numerical simulations of the impulsive acceleration of a dense gas curtain in air by a Mach 1.21 planar shock are carried out by solving the 3D compressible multi-species Navier-Stokes equations coupled with localized artificial diffusivity method to capture discontinuities in the flow field. The simulations account for the presence of three species in the flow field: air, and acetone (used as a tracer species in the experiments). Simulations at different concentration levels of the species are conducted and the temporal evolution of the curtain width is compared with the measured data from the experimental studies by Balakumar et al. (Phys Fluids 20:124103-124113, 2008). The instantaneous density and velocity fields at two different times (prior and after the reshock) are compared with experimental data and show good qualitative agreement. The reshock process is studied by re-impacting the evolving curtain with the reflected shock wave. Reshock causes enhanced mixing and destroys the ordered velocity field causing a chaotic flow. The unsteady flow field is characterized by computing statistics of certain flow variables using two different definitions of the mean flow. The average profiles conditioned on the heavy gas (comprising and acetone) and the corresponding fluctuating fields provide metrics which are more suitable to comparing with experimentally measured data. Mean profiles (conditioned on the heavy gas) of stream-wise velocity, variance of stream-wise velocity, and turbulent kinetic energy and PDF (probability distribution function) of fluctuating velocity components are computed at two different times along the flow evolution and are seen to show trend towards grid convergence. The spectra of turbulent kinetic energy and scalar energy (of mass fraction of heavy gas) show the existence of more than half decade of inertial sub-range at late times following reshock. The Reynolds stresses in the domain are reported while identifying the term that is dominant in its contribution to the Reynolds stresses.
Simultaneous density-field visualization and PIV of the Richtmyer-Meshkov instability
NASA Astrophysics Data System (ADS)
Prestridge, Katherine; Rightley, Paul; Benjamin, Robert; Kurnit, Norman; Boxx, Isaac; Vorobieff, Peter
1999-11-01
We describe a highly-detailed experimental characterization of the Richtmyer-Meshkov instability. A vertical curtain of heavy gas (SF_6) flows into the test section of an air-filled, horizontal shock tube, and the instability evolves after the passage of a Mach 1.2 shock past the curtain. The evolution of the curtain is visualized by seeding the SF6 with small (d ≈ 0.5 μm) glycol/water droplets using a modified theatrical fog generator. Because the event lasts only 1 ms and the initial conditions vary from test to test, rapid and high-resolution (both spatial and temporal) data acquisition is required in order to characterize the initial and dynamic conditions for each experimental event. A customized, frequency-doubled, burst mode Nd:YAG laser and a commercial single-pulse laser are used for the implementation of simultaneous density-field imaging and PIV diagnostics. We have provided data about flow scaling and mixing through image analysis, and PIV data gives us further quantitative physical insight into the evolution of the Richtmyer-Meshkov instability.
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2014 CFR
2014-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2012 CFR
2012-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2013 CFR
2013-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2010 CFR
2010-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
40 CFR 63.11409 - What are the standards?
Code of Federal Regulations, 2011 CFR
2011-07-01
...) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium... capture system that collects the gases and fumes released during the operation of each emissions source...
DNA strand breakage and lipid peroxidation after exposure to welding fumes in vivo.
Chuang, Cheng-Hung; Huang, Chong-En; Chen, Hsiu-Ling
2010-01-01
A remarkable number of complex aerosols are generated from welding processes. The objective of this study was to compare DNA damage and lipid peroxidation in plasma and in lung and in liver tissue of rats exposed to welding fumes in an exposure chamber with those of control animals. Three air samples from the chamber were also collected to assess the exposure dose for each exposure (total samplings = 18). Eight male Sprague-Dawley rats were exposed to welding fumes at a concentration of 1540.76 mg/m(3) for 10 min/day six times on day 1, day 3, day 7, day 15, day 30 and day 40. Lung, liver and kidney injury was measured following exposure, as well as in unexposed control rats (n = 4 at the beginning of the study). DNA strand breakage [tail moment (TMOM)] in exposed animals showed significant differences at day 1, day 4, day 7 and day 15 relative to the levels in control animals. Malondialdehyde (MDA, a lipid peroxidation product) levels increased gradually post-welding to 0.4 microM at 7 days. MDA and TMOM both reached maximum levels 7 days after the first exposure. At the start, an increasing trend in DNA strand breakage was more obvious than increases in MDA levels; MDA seemed to reflect long-term effects of exposure to welding fumes since it increased after 7 days and was sustained to 40 days in vivo. Significant differences in both MDA levels and DNA strand breakage were seen in lung, liver and kidney 40 days after the first fume inhalation. We conclude that acute exposure of rats to welding fumes causes noticeable oxidative damage and lipid peroxidation effects and that DNA damage may recover after long and repeat exposure. More chronic inhalation and low-dose studies are needed in order to further assess the effects of inhalation of welding fumes on DNA and to elucidate the possible causal mechanisms associated with the biologically damaging effects of welding fumes.
Stanisławska, Magdalena; Janasik, Beata; Trzcinka-Ochocka, Małgorzata
2011-01-01
Occupational exposure to welding fumes is a known health hazard. The aim of this study was to determine concentrations of welding fumes components such as: iron, manganese, nickel and chromium (including chromium speciation) to assess exposure of stainless steel welders. The survey covered 14 workers of two metallurgic plants engaged in welding stainless steel (18% Cr and 8% Ni) by different techniques: manual metal arc (MMA), metal inert gas (MIG) and tungsten inert gas (TIG). Personal air samples were collected in the welders' breathing zone over a period of about 6-7 h (dust was collected on a membrane and glass filter) to determine time weighted average (TWA) concentration of welding fumes and its components. The concentrations of welding fumes (total particulate) were determined with use of the gravimetric method. Concentrations and welding fume components, such as: iron, manganese, nickel and chromium were determined by ICP-MS technique. The total hexavalent chromium was analyzed by applying the spectrophotometry method according to NIOSH. The water-soluble chromium species were analyzed by HPLC-ICP-MS. Time weighted average concentrations of the welding fumes and its components at the worker's breathing zone were (mg/m3): dust, 0.14-10.7; iron, 0.004-2.9; manganese, 0.001-1.12; nickel, < 0.001-0.2; and chromium <0.002-0.85 (mainly Cr(III) and insoluble Cr(VI)). The maximum admissible limits for workplace pollutants (TLV-TWA) were exceeded for manganese and for insoluble chromium Cr (VI). For Cr (III) the limit was exceeded in individual cases. The assessment of the workers' occupational exposure, based on the determined time weighted average (TWA) of fumes and their components, shows that the stainless steel welders worked in conditions harmful to their health owing to the significantly exceeded maximum admissible limits for manganese and the exceeded TLV value for insoluble chromium (VI).
Development testing of large volume water sprays for warm fog dispersal
NASA Technical Reports Server (NTRS)
Keller, V. W.; Anderson, B. J.; Burns, R. A.; Lala, G. G.; Meyer, M. B.; Beard, K. V.
1986-01-01
A new brute-force method of warm fog dispersal is described. The method uses large volume recycled water sprays to create curtains of falling drops through which the fog is processed by the ambient wind and spray induced air flow. Fog droplets are removed by coalescence/rainout. The efficiency of the technique depends upon the drop size spectra in the spray, the height to which the spray can be projected, the efficiency with which fog laden air is processed through the curtain of spray, and the rate at which new fog may be formed due to temperature differences between the air and spray water. Results of a field test program, implemented to develop the data base necessary to assess the proposed method, are presented. Analytical calculations based upon the field test results indicate that this proposed method of warm fog dispersal is feasible. Even more convincingly, the technique was successfully demonstrated in the one natural fog event which occurred during the test program. Energy requirements for this technique are an order of magnitude less than those to operate a thermokinetic system. An important side benefit is the considerable emergency fire extinguishing capability it provides along the runway.
73. LIQUID NITROGEN PUMPING STATION ON WEST SIDE OF MST; ...
73. LIQUID NITROGEN PUMPING STATION ON WEST SIDE OF MST; NITROGEN EXCHANGERS ON RIGHT. SOUTHWEST CORNER OF MST VISIBLE; ENVIRONMENTAL CURTAIN SWING AND PLATFORM EXTENDED. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA
17. VIEW OF INTERIOR, EAST SIDE, DECK LEVEL OF MST. ...
17. VIEW OF INTERIOR, EAST SIDE, DECK LEVEL OF MST. NOTE CANVAS CURTAIN (RIGHT) USED TO COVER SOUTH SIDE OF MST BELOW LOWEST ENVIRONMENTAL DOORS. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA
40 CFR 721.10583 - Benzenamine, 4,4′-[1,3-phenylenebis(1-methylethylidene)]bis-.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., tight-fitting half-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters... aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters. (D) NIOSH...
40 CFR 721.10583 - Benzenamine, 4,4′-[1,3-phenylenebis(1-methylethylidene)]bis-.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., tight-fitting half-face respirator equipped with N100 (if oil aerosols absent), R100, or P100 filters... aerosols absent), R100, or P100 filters. (C) NIOSH-certified powered air-purifying respirator equipped with a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters. (D) NIOSH...
New approach to reducing water consumption in commercial kitchen hood
NASA Astrophysics Data System (ADS)
Asmuin, N.; Pairan, M. R.
2017-09-01
Water mist sprays are used in wide range of application. However it is depend to the spray characteristic to suit the particular application. The modern commercial kitchen hood ventilation system was adopted with the water mist nozzle technology as an additional tool to increase the filtration efficiency. However, low level of filtration effectiveness and high water consumption were the major problems among the Commercial Kitchen Ventilation expert. Therefore, this study aims to develop a new mist spray technology to replacing the conventional KSJB nozzle (KSJB is a nozzle’s name). At the same time, an appropriate recommended location to install the nozzle in kitchen hood system was suggested. An extensive simulation works were carried out to observe the spray characteristics, ANSYS (FLUENT) was used for simulation wise. In the case of nozzle studies, nozzles were tested at 1 bar pressure of water and air. In comparison with conventional nozzles configuration, this new approach suggested nozzle configuration was reduce up to 50% of water consumption, which by adopted 3 numbers of nozzles instead of 6 numbers of nozzles in the commercial kitchen hood system. Therefore, this nozzle will be used in industry for their benefits of water consumption, filtration efficiency and reduced the safety limitations.
Waste Minimization Program. Air Force Plant 4.
1986-02-01
incinerator equipped with a secondary combustion chamber and venturi scrubber could serve AFP 4’s needs. As the wastes listed in Table 3-6 contain negligible... scrubber water treatment in the AFP 4eatment. waste treatment system. 2.3 ECONOMICS -Table 2-3 summarizes the projected economics of the recommendations for...control devices. These paint booths are equipped with water curtain air scrubbers which remove solids from the booth exhaust by providing - intimate
Bertram, Jens; Brand, Peter; Hartmann, Laura; Schettgen, Thomas; Kossack, Veronika; Lenz, Klaus; Purrio, Ellwyn; Reisgen, Uwe; Kraus, Thomas
2015-10-01
Several existing field studies evaluate aluminium welding works but no thoroughly controlled exposure scenario for welding fume has been described yet. This study provides information about the uptake and elimination of aluminium from welding fumes under controlled conditions. In the Aachen Workplace Simulation Laboratory, we are able to generate welding fumes of a defined particle mass concentration. We exposed 12, until then occupationally unexposed participants with aluminium-containing welding fumes of a metal inert gas (MIG) welding process of a total dust mass concentration of 2.5 mg/m(3) for 6 h. Room air filter samples were collected, and the aluminium concentration in air derived. Urine and plasma samples were collected directly before and after the 6-h lasting exposure, as well as after 1 and 7 days. Human biomonitoring methods were used to determine the aluminium content of the samples with high-resolution continuum source atomic absorption spectrometry. Urinary aluminium concentrations showed significant changes after exposure compared to preexposure levels (mean t(1) (0 h) 13.5 µg/L; mean t(2) (6 h) 23.5 µg/L). Plasma results showed the same pattern but pre-post comparison did not reach significance. We were able to detect a significant increase of the internal aluminium burden of a single MIG aluminium welding process in urine, while plasma failed significance. Biphasic elimination kinetic can be observed. The German BAT of 60 µg/g creatinine was not exceeded, and urinary aluminium returned nearly to baseline concentrations after 7 days.
NASA Technical Reports Server (NTRS)
Nguyen, Myngoc T.; Lapointe, Stephen; Jennings, Brittney; Zoumplis, Angela
2011-01-01
On April 20, 2010, an oil platform belonging to BP exploded and leaked a huge volume of oil into the Gulf of Mexico. In an effort to control the spread of the oil, BP applied dispersants such as Corexit and conducted in-situ burnings of the oil. This catastrophe created a complex chain of events that affected not only the fragile water and land ecosystems, but the humans who breathe the air every day. Thousands of people were exposed to fumes associated with oil vapors from the spill, burning of the oil, and the toxic mixture of dispersants. While aiding in clean-up efforts, local fishermen were directly exposure to fumes when working on the Gulf. A notable amount of Gulf Coast residents were also exposed to the oil fumes as seasonal southeasterly winds blew vapors toward land. The Volatile Organic Compounds (VOC) found in oil vapors include: benzene, toluene, ethyl benzene, xylene, naphthalene, hydrogen sulfide and particulate matter (PM). Increases in water temperature and sunlight due to the summer season allow for these VOCs and PM to evaporate into the air more rapidly. Aside from the VOCs found in oil vapors, the dispersant being used to break up the oil is highly toxic and is thought to be even more toxic than the oil itself (EPA website, 2010). To protect human health, the environment, and to make informed policy decisions relevant to the spill, the EPA Region 6 has continuously monitored the affected areas carefully for levels of pollutants in the outdoor air that are associated with petroleum products and the burning of oil along the coast. In an effort to prevent, prepare for, and respond to future oil spills that occur in and around inland waters of the United States, the EPA has been working with local, state, and federal response partners. Air quality measurements were collected by the EPA at five active monitoring systems stationed along the coast.
40 CFR 62.14770 - When must I achieve final compliance?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14770 When must I achieve final compliance? If you plan to continue...
40 CFR 62.14770 - When must I achieve final compliance?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14770 When must I achieve final compliance? If you plan to continue...
40 CFR 62.14770 - When must I achieve final compliance?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14770 When must I achieve final compliance? If you plan to continue...
40 CFR 62.14770 - When must I achieve final compliance?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14770 When must I achieve final compliance? If you plan to continue...
40 CFR 62.14770 - When must I achieve final compliance?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14770 When must I achieve final compliance? If you plan to continue...
Characterization of Tungsten Inert Gas (TIG) Welding Fume Generated by Apprentice Welders
Graczyk, Halshka; Lewinski, Nastassja; Zhao, Jiayuan; Concha-Lozano, Nicolas; Riediker, Michael
2016-01-01
Tungsten inert gas welding (TIG) represents one of the most widely used metal joining processes in industry. Its propensity to generate a greater portion of welding fume particles at the nanoscale poses a potential occupational health hazard for workers. However, current literature lacks comprehensive characterization of TIG welding fume particles. Even less is known about welding fumes generated by welding apprentices with little experience in welding. We characterized TIG welding fume generated by apprentice welders (N = 20) in a ventilated exposure cabin. Exposure assessment was conducted for each apprentice welder at the breathing zone (BZ) inside of the welding helmet and at a near-field (NF) location, 60cm away from the welding task. We characterized particulate matter (PM4), particle number concentration and particle size, particle morphology, chemical composition, reactive oxygen species (ROS) production potential, and gaseous components. The mean particle number concentration at the BZ was 1.69E+06 particles cm−3, with a mean geometric mean diameter of 45nm. On average across all subjects, 92% of the particle counts at the BZ were below 100nm. We observed elevated concentrations of tungsten, which was most likely due to electrode consumption. Mean ROS production potential of TIG welding fumes at the BZ exceeded average concentrations previously found in traffic-polluted air. Furthermore, ROS production potential was significantly higher for apprentices that burned their metal during their welding task. We recommend that future exposure assessments take into consideration welding performance as a potential exposure modifier for apprentice welders or welders with minimal training. PMID:26464505
40 CFR 721.10279 - Multi-walled carbon nanotubes (generic) (P-10-246).
Code of Federal Regulations, 2014 CFR
2014-07-01
... a loose-fitting hood or helmet and high efficiency particulate air (HEPA) filters; or (C) NIOSH... in § 721.80(f), (k) (conductivity additive to resins, rubber, and to battery electrodes), and (q...
Fayerweather, William E; Trumbore, David C; Johnson, Kathleen A; Niebo, Ronald W; Maxim, L Daniel
2011-09-01
This paper summarizes available data on worker exposures to asphalt fume (soluble fraction), total particulate matter, and respirable crystalline silica (quartz) [hereinafter RCS] over a 30-year period in Owens Corning's asphalt production and roofing manufacturing plants. For the period 1977 through 2006, the air-monitoring database contains more than 1,400 personal samples for asphalt fume (soluble fraction), 2,400 personal samples for total particulate, and 1,300 personal samples for RCS. Unique process-job categories were identified for the asphalt production and roofing shingle manufacturing plants. Quantitative exposures were tabulated by agent, process-job, and calendar period to form an exposure matrix for use in subsequent epidemiologic studies of the respiratory health of these workers. Analysis of time trends in exposure data shows substantial and statistically significant exposure reductions for asphalt fume (soluble fraction), total particulate matter, and respirable crystalline silica at Owens Corning plants. Cumulative distribution plots for the most recent sampling period (2001-2006) show that 95% of the asphalt fume (soluble fraction) measurements were less than 0.25 mg/m3; 95% of the total particulate measurements were less than 2.2 mg/m3; and 95% of the RCS measurements were less than 0.05 mg/m3. Several recommendations are offered to improve the design of future monitoring efforts.
Exposure to Inhalable, Respirable, and Ultrafine Particles in Welding Fume
Pesch, Beate
2012-01-01
This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m−3 for inhalable and 1.29 mg m−3 for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m−3). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements
Exposure to inhalable, respirable, and ultrafine particles in welding fume.
Lehnert, Martin; Pesch, Beate; Lotz, Anne; Pelzer, Johannes; Kendzia, Benjamin; Gawrych, Katarzyna; Heinze, Evelyn; Van Gelder, Rainer; Punkenburg, Ewald; Weiss, Tobias; Mattenklott, Markus; Hahn, Jens-Uwe; Möhlmann, Carsten; Berges, Markus; Hartwig, Andrea; Brüning, Thomas
2012-07-01
This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m(-3) for inhalable and 1.29 mg m(-3) for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m(-3)). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements
Work environments and exposure to hazardous substances in korean tire manufacturing.
Lee, Naroo; Lee, Byung-Kyu; Jeong, Sijeong; Yi, Gwang Yong; Shin, Jungah
2012-06-01
The purpose of this study is to evaluate the tire manufacturing work environments extensively and to identify workers' exposure to hazardous substances in various work processes. Personal air sampling was conducted to measure polycyclic aromatic hydrocarbons, carbon disulfide, 1,3-butadiene, styrene, methyl isobutyl ketone, methylcyclohexane, formaldehyde, sulfur dioxide, and rubber fume in tire manufacturing plants using the National Institute for Occupational Safety Health Manual of Analytical Methods. Noise, carbon monoxide, and heat stress exposure were evaluated using direct reading instruments. Past concentrations of rubber fume were assessed using regression analysis of total particulate data from 2003 to 2007, after identifying the correlation between the concentration of total particulate and rubber fume. Workers were exposed to rubber fume that exceeded 0.6 mg/m(3), the maximum exposure limit of the UK, in curing and production management processes. Forty-seven percent of workers were exposed to noise levels exceeding 85 dBA. Workers in the production management process were exposed to 28.1℃ (wet bulb globe temperature value, WBGT value) even when the outdoor atmosphere was 2.7℃ (WBGT value). Exposures to other substances were below the limit of detection or under a tenth of the threshold limit values given by the American Conference of Governmental Industrial Hygienists. To better classify exposure groups and to improve work environments, examining closely at rubber fume components and temperature as risk indicators in tire manufacturing is recommended.
An effective system to produce smoke solutions from dried plant tissue for seed germination studies1
Coons, Janice; Coutant, Nancy; Lawrence, Barbara; Finn, Daniel; Finn, Stephanie
2014-01-01
• Premise of the study: An efficient and inexpensive system was developed to produce smoke solutions from plant material to research the influence of water-soluble compounds from smoke on seed germination. • Methods and Results: Smoke solutions (300 mL per batch) were produced by burning small quantities (100–200 g) of dried plant material from a range of species in a bee smoker attached by a heater hose to a side-arm flask. The flask was attached to a vacuum water aspirator, to pull the smoke through the water. The entire apparatus was operated in a laboratory fume hood. • Conclusions: Compared with other smoke solution preparation systems, the system described is easy to assemble and operate, inexpensive to build, and effective at producing smoke solutions from desired species in a small indoor space. Quantitative measurements can be made when using this system, allowing for replication of the process. PMID:25202613
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Ying, E-mail: liu.ying.48r@st.kyoto-u.ac.jp; Imashuku, Susumu; Sasaki, Nobuharu
In this study, a portable total reflection x-ray fluorescence (TXRF) spectrometer was used to analyze unknown laboratory hazards that precipitated on exterior surfaces of cooling pipes and fume hood pipes in chemical laboratories. With the aim to examine the accuracy of TXRF analysis for the determination of elemental composition, analytical results were compared with those of wavelength-dispersive x-ray fluorescence spectrometry, scanning electron microscope and energy-dispersive x-ray spectrometry, energy-dispersive x-ray fluorescence spectrometry, inductively coupled plasma atomic emission spectrometry, x-ray diffraction spectrometry (XRD), and x-ray photoelectron spectroscopy (XPS). Detailed comparison of data confirmed that the TXRF method itself was not sufficient tomore » determine all the elements (Z > 11) contained in the samples. In addition, results suggest that XRD should be combined with XPS in order to accurately determine compound composition. This study demonstrates that at least two analytical methods should be used in order to analyze the composition of unknown real samples.« less
Oxidative aliphatic C-H fluorination with manganese catalysts and fluoride ion
Liu, Wei; Huang, Xiongyi; Groves, John T
2014-01-01
Fluorination is a reaction that is useful in improving the chemical stability and changing the binding affinity of biologically active compounds. The protocol described here can be used to replace aliphatic, C(sp3)-H hydrogen in small molecules with fluorine. Notably, isolated methylene groups and unactivated benzylic sites are accessible. The method uses readily available manganese porphyrin and manganese salen catalysts and various fluoride ion reagents, including silver fluoride (AgF), tetrabutylammonium fluoride and triethylamine trihydrofluoride (TREAT·HF), as the source of fluorine. Typically, the reactions afford 50–70% yield of mono-fluorinated products in one step. Two representative examples, the fragrance component celestolide and the nonsteroidal anti-inflammatory drug ibuprofen, are described; they produced useful isolated quantities (250–300 mg, ~50% yield) of fluorinated material over periods of 1–8 h. The procedures are performed in a typical fume hood using ordinary laboratory glassware. No special precautions to rigorously exclude water are required. PMID:24177292
Safety in the SEM laboratory--1981 update
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bance, G.N.; Barber, V.C.; Sholdice, J.A.
1981-01-01
The article reviews recent information on hazards as they relate to safety in SEM laboratories. The first section lists the safety equipment that should be available in a SEM laboratory. Flammable and combustible liquids are discussed, and particular warnings are given concerning the fire and explosion risks associated with diethyl ether and diisopropyl ether. The possible hazards associated with electrical equipment, and the risk of X-ray emissions from EM's are briefly outlined. The hazards associated with acute and chronic toxicity of chemicals used in the EM laboratory are discussed. The need to reduce exposure to a growing list of recognizablemore » hazardous chemicals is emphasized. This reduction can be accomplished by more extensive use of functioning fume hoods, and the use of more appropriate and effective protective gloves. Allergies and the hazards of dangerous pathogens in the SEM laboratory are discussed. The explosion and other hazards associated with cryogens, vacuum evaporators, critical point dryers, and compressed gas cylinders are emphasized.« less
Verifying mixing in dilution tunnels How to ensure cookstove emissions samples are unbiased
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, Daniel L.; Rapp, Vi H.; Caubel, Julien J.
A well-mixed diluted sample is essential for unbiased measurement of cookstove emissions. Most cookstove testing labs employ a dilution tunnel, also referred to as a “duct,” to mix clean dilution air with cookstove emissions before sampling. It is important that the emissions be well-mixed and unbiased at the sampling port so that instruments can take representative samples of the emission plume. Some groups have employed mixing baffles to ensure the gaseous and aerosol emissions from cookstoves are well-mixed before reaching the sampling location [2, 4]. The goal of these baffles is to to dilute and mix the emissions stream withmore » the room air entering the fume hood by creating a local zone of high turbulence. However, potential drawbacks of mixing baffles include increased flow resistance (larger blowers needed for the same exhaust flow), nuisance cleaning of baffles as soot collects, and, importantly, the potential for loss of PM2.5 particles on the baffles themselves, thus biasing results. A cookstove emission monitoring system with baffles will collect particles faster than the duct’s walls alone. This is mostly driven by the available surface area for deposition by processes of Brownian diffusion (through the boundary layer) and turbophoresis (i.e. impaction). The greater the surface area available for diffusive and advection-driven deposition to occur, the greater the particle loss will be at the sampling port. As a layer of larger particle “fuzz” builds on the mixing baffles, even greater PM2.5 loss could occur. The micro structure of the deposited aerosol will lead to increased rates of particle loss by interception and a tendency for smaller particles to deposit due to impaction on small features of the micro structure. If the flow stream could be well-mixed without the need for baffles, these drawbacks could be avoided and the cookstove emissions sampling system would be more robust.« less
... on unwashed hands). Being exposed to tobacco smoke, air pollution, dusts, vapors, and fumes can also cause acute bronchitis. Less often, bacteria can also cause acute bronchitis. To diagnose acute bronchitis, your health care provider will ask about your symptoms and ...
35. OFFICE OF THE QUARTERMASTER GENERAL; CONSTRUCTION DIVISION; PLAN NUMBER ...
35. OFFICE OF THE QUARTERMASTER GENERAL; CONSTRUCTION DIVISION; PLAN NUMBER 800-196. MOBILIZATION BUILDINGS; STANDARD HEATING DETAILS; WARM AIR HEATING; SMOKE PIPES & VENT HOODS FOR RANGES. - Fort McCoy, Building T-1129, Sparta, Monroe County, WI
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilcox, Brian; May, Doug; Howlett, Don
2013-07-01
Whiteshell Laboratories (WL) is a nuclear research establishment owned by the Canadian government and operated by Atomic Energy of Canada Limited (AECL) since the early 1960's. WL is currently under a decommissioning license and the mandate is to remediate the nuclear legacy liabilities in a safe and cost effective manner. The WL Project is the first major nuclear decommissioning project in Canada. A major initiative underway is to decommission and demolish the main R and D Laboratory complex. The Building 300 R and D complex was constructed to accommodate laboratories and offices which were mainly used for research and developmentmore » associated with organic-cooled reactors, nuclear fuel waste management, reactor safety, advanced fuel cycles and other applications of nuclear energy. Building 300 is a three storey structure of approximately 16,000 m{sup 2}. In order to proceed with building demolition, the contaminated systems inside the building have to be characterized, removed, and the waste managed. There is a significant focus on volume reduction of radioactive waste for the WL project. The active ventilation system is one of the significant contaminated systems in Building 300 that requires decommissioning and removal. The active ventilation system was designed to manage hazardous fumes and radioactivity from ventilation devices (e.g., fume hoods, snorkels and glove boxes) and to prevent the escape of airborne hazardous material outside of the laboratory boundary in the event of an upset condition. The system includes over 200 ventilation devices and 32 active exhaust fan units and high efficiency particulate air (HEPA) filters. The strategy to remove the ventilation system was to work from the laboratory end back to the fan/filter system. Each ventilation duct was radiologically characterized. Fogging was used to minimize loose contamination. Sections of the duct were removed by various cutting methods and bagged for temporary storage prior to disposition. Maintenance of building heating, ventilation and air conditioning (HVAC) balancing was critical to ensure proper airflow and worker safety. Approximately 103 m{sup 3} of equipment and materials were recovered or generated by the project. Low level waste accounted for approximately 37.4 m{sup 3}. Where possible, ducting was free released for metal recycling. Contaminated ducts were compacted into B-1000 containers and stored in a Shielded Modular Above-Ground Storage Facility (SMAGS) on the WL site awaiting final disposition. The project is divided into three significant phases, with Phases 1 and 2 completed. Lessons learned during the execution of Phases 1 and 2 have been incorporated into the current ventilation removal. (authors)« less
Workplace Exposure to Titanium Dioxide Nanopowder Released from a Bag Filter System
Ji, Jun Ho; Kim, Jong Bum; Lee, Gwangjae; Noh, Jung-Hun; Yook, Se-Jin; Cho, So-Hye; Bae, Gwi-Nam
2015-01-01
Many researchers who use laboratory-scale synthesis systems to manufacture nanomaterials could be easily exposed to airborne nanomaterials during the research and development stage. This study used various real-time aerosol detectors to investigate the presence of nanoaerosols in a laboratory used to manufacture titanium dioxide (TiO2). The TiO2 nanopowders were produced via flame synthesis and collected by a bag filter system for subsequent harvesting. Highly concentrated nanopowders were released from the outlet of the bag filter system into the laboratory. The fractional particle collection efficiency of the bag filter system was only 20% at particle diameter of 100 nm, which is much lower than the performance of a high-efficiency particulate air (HEPA) filter. Furthermore, the laboratory hood system was inadequate to fully exhaust the air discharged from the bag filter system. Unbalanced air flow rates between bag filter and laboratory hood systems could result in high exposure to nanopowder in laboratory settings. Finally, we simulated behavior of nanopowders released in the laboratory using computational fluid dynamics (CFD). PMID:26125024
Use of electric and bubble barriers to limit the movement of Eurasian ruffe (Gymnocephalus cernuus)
Dawson, Heather A.; Reinhardt, Ulrich G.; Savino, Jacqueline F.
2006-01-01
Eurasian ruffe (Gymnocephalus cernuus) is an aquatic invasive species accidentally introduced via ballast water to the Great Lakes in the mid-1980s. Fish barrier technology is being studied to stop the spread of invasive fish species such as ruffe. Electrical barriers have been constructed, most notably in the Chicago Sanitary and Ship Canal, to prevent non-indigenous species such as ruffe from spreading into areas where they are currently absent. Information on the response of an invasive fish to barriers can help managers determine strategies to prevent the spread of these species via artificial waterways. In this laboratory study electrical barriers were set up to determine effectiveness of four electrical settings for repelling Eurasian ruffe measuring 10 cm or more in length. In separate tests, airbubble curtains with two bubble sizes and densities were created to test this type of barrier in blocking movement of ruffe less than 10 cm in length. The most effective electrical settings found (5 ms, 6 Hz) repelled only about half of the attempted passes. When ruffe were offered food or shelter on the opposite side of the electrical barrier, neither food-starved nor shelter-deprived ruffe made significantly more attempts to cross the barrier. Ruffe were significantly repelled by all air-bubble curtains, but a large proportion of passes (4.5 passes per fish on average in the treatments) were still observed. Electrical barrier settings and air-bubble curtains used in this study were found ineffective at completely blocking the movement, but somewhat effective at inhibiting the passage of ruffe.
Chemical warfare protection for the cockpit of future aircraft
NASA Technical Reports Server (NTRS)
Pickl, William C.
1988-01-01
Currently systems are being developed which will filter chemical and biological contaminants from crew station air. In order to maximize the benefits of these systems, a method of keeping the cockpit contaminant free during pilot ingress and egress is needed. One solution is to use a rectangular plastic curtain to seal the four edges of the canopy frame to the canopy sill. The curtain is stored in a tray which is recessed into the canopy sill and unfolds in accordion fashion as the canopy is raised. A two way zipper developed by Calspan could be used as an airlock between the pilot's oversuit and the cockpit. This system eliminates the pilot's need for heavy and restrictive CB gear because he would never be exposed to the chemical warfare environment.
40 CFR 60.2260 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2012 CFR
2012-07-01
... SOURCES Standards of Performance for Commercial and Industrial Solid Waste Incineration Units for Which... initial and annual opacity tests onsite in either paper copy or electronic format, unless the... as electronic or paper copy on or before the applicable submittal date. (f) Keep a copy of the...
40 CFR 60.2260 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2010 CFR
2010-07-01
... SOURCES Standards of Performance for Commercial and Industrial Solid Waste Incineration Units for Which... initial and annual opacity tests onsite in either paper copy or electronic format, unless the... as electronic or paper copy on or before the applicable submittal date. (f) Keep a copy of the...
40 CFR 60.2870 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2011 CFR
2011-07-01
... SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration... records of results of all initial and annual opacity tests onsite in either paper copy or electronic... annual opacity test reports as electronic or paper copy on or before the applicable submittal date and...
40 CFR 60.2260 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2011 CFR
2011-07-01
... SOURCES Standards of Performance for Commercial and Industrial Solid Waste Incineration Units for Which... initial and annual opacity tests onsite in either paper copy or electronic format, unless the... as electronic or paper copy on or before the applicable submittal date. (f) Keep a copy of the...
40 CFR 60.2870 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2012 CFR
2012-07-01
... SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration... onsite in either paper copy or electronic format, unless the Administrator approves another format, for... the previous report. (e) Submit initial and annual opacity test reports as electronic or paper copy on...
40 CFR 60.2870 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2010 CFR
2010-07-01
... SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration... records of results of all initial and annual opacity tests onsite in either paper copy or electronic... annual opacity test reports as electronic or paper copy on or before the applicable submittal date and...
40 CFR 60.2870 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2013 CFR
2013-07-01
... SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration... onsite in either paper copy or electronic format, unless the Administrator approves another format, for... report. (e) Submit initial and annual opacity test reports as electronic or paper copy on or before the...
40 CFR 60.2870 - What are the recordkeeping and reporting requirements for air curtain incinerators?
Code of Federal Regulations, 2014 CFR
2014-07-01
... SOURCES Emissions Guidelines and Compliance Times for Commercial and Industrial Solid Waste Incineration... onsite in either paper copy or electronic format, unless the Administrator approves another format, for... report. (e) Submit initial and annual opacity test reports as electronic or paper copy on or before the...
40 CFR 60.2994 - Are air curtain incinerators regulated under this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... and Compliance Times for Other Solid Waste Incineration Units That Commenced Construction On or Before... percent wood waste. (2) 100 percent clean lumber. (3) 100 percent yard waste. (4) 100 percent mixture of only wood waste, clean lumber, and/or yard waste. Model Rule—Use of Model Rule ...
40 CFR 60.2888 - Are air curtain incinerators regulated under this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Performance for Other Solid Waste Incineration Units for Which Construction is Commenced After December 9... other requirements of this subpart. (1) 100 percent wood waste. (2) 100 percent clean lumber. (3) 100 percent yard waste. (4) 100 percent mixture of only wood waste, clean lumber, and/or yard waste. ...
40 CFR 1033.525 - Smoke testing.
Code of Federal Regulations, 2010 CFR
2010-07-01
... rectangular duct), you may align the beam to have a different path length and correct it to be equivalent to a... that maximum response below 430 nanometers and above 680 nanometers). (4) Attach a collimating tube to... light. (6) You may use an air curtain across the light source and detector window assemblies to minimize...
40 CFR 62.14795 - How do I achieve final compliance?
Code of Federal Regulations, 2010 CFR
2010-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14795 How do I achieve final compliance? For the final compliance, you must...
40 CFR 62.14795 - How do I achieve final compliance?
Code of Federal Regulations, 2011 CFR
2011-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14795 How do I achieve final compliance? For the final compliance, you must...
40 CFR 62.14795 - How do I achieve final compliance?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14795 How do I achieve final compliance? For the final compliance, you must...
40 CFR 62.14795 - How do I achieve final compliance?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14795 How do I achieve final compliance? For the final compliance, you must...
40 CFR 60.56b - Standards for air curtain incinerators.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Municipal Waste Combustors for Which Construction is Commenced After September 20, 1994 or for Which... the capacity to combust greater than 250 tons per day of municipal solid waste and that combusts a fuel feed stream composed of 100 percent yard waste and no other municipal solid waste materials shall...
40 CFR 62.14795 - How do I achieve final compliance?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Air Curtain Incinerators That Burn 100 Percent Wood Wastes, Clean Lumber And/or Yard Waste § 62.14795 How do I achieve final compliance? For the final compliance, you must...
Scharrer, E; Hessel, H; Kronseder, A; Guth, W; Rolinski, B; Jörres, R A; Radon, K; Schierl, R; Angerer, P; Nowak, D
2007-02-01
The present study aimed to investigate, whether short-term experimental exposure to high levels of welding fumes would be capable of exerting acute effects in healthy subjects. Specifically, we assessed cardiovascular function in terms of heart rate variability (HRV) as well as the concentrations of inflammatory mediators and hemostatic proteins in blood as outcome measures. Twenty subjects without a history of airway and cardiovascular diseases were exposed to either control air or welding fume for 1 h on 2 separate days under standardized conditions. The median concentration of the alveolar particle fraction during welding was 3.5 mg/m(3 )(quartiles: 1.4-6.3 mg/m(3); range 1.0-25.3 mg/m(3)). Five hours later a panel of clinical assessments was performed, including HRV measurement and drawing of blood samples. There were no changes in symptom ratings or lung function after welding fume exposure. Exposures did also not differ regarding effects on time- and frequency-domain parameters of HRV. Similarly, blood leukocyte numbers, cell differentials and the blood levels of fibrinogen, C-reactive protein, antithrombin III, factor VIII, von Willebrand factor, ristocetin cofactor, sICAM-1, tumor necrosis factor alpha, interleukin 6, interleukin 8 and epithelial neutrophil activating peptide 78 were not altered by welding fume inhalation. However, there was a significant fall in the level of endothelin-1 (P < 0.01). In conclusion, the data did not indicate effects of clinical significance of a short-term high-level exposure to welding fumes on HRV or a set of blood hemostatic and acute inflammatory parameters in healthy subjects. The small but statistically significant effect on endothelin levels demonstrated that measurable effects could be elicited even in these individuals. Overall, welding fumes are not likely to exert acute cardiovascular effects in healthy individuals.
Niemelä, R; Koskela, H; Engström, K
2001-08-01
The purpose of the study was to investigate the performance of displacement ventilation in a large factory hall where large components of stainless steel for paper, pulp and chemical industries were manufactured. The performance of displacement ventilation was evaluated in terms of concentration distributions of welding fumes and grinding particles, flow field of the supply air and temperature distributions. Large differences in vertical stratification patterns between hexavalent chromium (Cr(VI)) and other particulate contaminants were observed. The concentration of Cr(VI) was notably lower in the zone of occupancy than in the upper part of the factory hall, whereas the concentrations of total airborne particles and trivalent chromium (Cr(III)) were higher in the occupied zone than in the upper zone. The stratification of Cr(VI) had the same tendency as the air temperature stratification caused by the displacement flow field.
Hood River Passive House, Hood River, Oregon (Fact Sheet)
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
2014-02-01
The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to "reduce home energy use by 30%-50%" (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift Housemore » and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.« less
Volcano hazards in the Mount Hood region, Oregon
Scott, W.E.; Pierson, T.C.; Schilling, S.P.; Costa, J.E.; Gardner, C.A.; Vallance, J.W.; Major, J.J.
1997-01-01
Mount Hood is a potentially active volcano close to rapidly growing communities and recreation areas. The most likely widespread and hazardous consequence of a future eruption will be for lahars (rapidly moving mudflows) to sweep down the entire length of the Sandy (including the Zigzag) and White River valleys. Lahars can be generated by hot volcanic flows that melt snow and ice or by landslides from the steep upper flanks of the volcano. Structures close to river channels are at greatest risk of being destroyed. The degree of hazard decreases as height above a channel increases, but large lahars can affect areas more than 30 vertical meters (100 vertical feet) above river beds. The probability of eruption-generated lahars affecting the Sandy and White River valleys is 1-in-15 to l-in-30 during the next 30 years, whereas the probability of extensive areas in the Hood River Valley being affected by lahars is about ten times less. The accompanying volcano-hazard-zonation map outlines areas potentially at risk and shows that some areas may be too close for a reasonable chance of escape or survival during an eruption. Future eruptions of Mount Hood could seriously disrupt transportation (air, river, and highway), some municipal water supplies, and hydroelectric power generation and transmission in northwest Oregon and southwest Washington.
Total fume and metal concentrations during welding in selected factories in Jeddah, Saudi Arabia.
Balkhyour, Mansour Ahmed; Goknil, Mohammad Khalid
2010-07-01
Welding is a major industrial process used for joining metals. Occupational exposure to welding fumes is a serious occupational health problem all over the world. The degree of risk to welder's health from fumes depends on composition, concentration, and the length of exposure. The aim of this study was to investigate workers' welding fume exposure levels in some industries in Jeddah, Saudi Arabia. In each factory, the air in the breathing zone within 0.5 m from welders was sampled during 8-hour shifts. Total particulates, manganese, copper, and molybdenum concentrations of welding fumes were determined. Mean values of eight-hour average particulate concentrations measured during welding at the welders breathing zone were 6.3 mg/m(3) (Factory 1), 5.3 mg/m(3) (Factory 2), 11.3 mg/m(3) (Factory 3), 6.8 mg/m(3) (Factory 4), 4.7 mg/m(3) (Factory 5), and 3.0 mg/m(3) (Factory 6). Mean values of airborne manganese, copper, and molybdenum levels measured during welding were in the range of 0.010 mg/m(3)-0.477 mg/m(3), 0.001 mg/m(3)-0.080 mg/m(3) and 0.001 mg/m(3)-0.058 mg/m(3) respectively. Mean values of calculated equivalent exposure values were: 1.50 (Factory 1), 1.56 (Factory 2), 5.14 (Factory 3), 2.21 (Factory 4), 2.89 (Factory 5), and 1.20 (Factory 6). The welders in factories 1, 2, 3, and 4 were exposed to welding fume concentration above the SASO limit value, which may increase the risk of respiratory health problems.
Wei, Yongyue; Wang, Zhaoxi; Chang, Chiung-yu; Fan, Tianteng; Su, Li; Chen, Feng; Christiani, David C
2013-01-01
Welding-associated air pollutants negatively affect the health of exposed workers; however, their molecular mechanisms in causing disease remain largely unclear. Few studies have systematically investigated the systemic toxic effects of welding fumes on humans. To explore the effects of welding fumes on the plasma metabolome, and to identify biomarkers for risk assessment of welding fume exposure. The two-stage, self-controlled exploratory study included 11 boilermakers from a 2011 discovery panel and 8 boilermakers from a 2012 validation panel. Plasma samples were collected pre- and post-welding fume exposure and analyzed by chromatography/mass spectrometry. Eicosapentaenoic or docosapentaenoic acid metabolic changes post-welding were significantly associated with particulate (PM2.5) exposure (p<0.05). The combined analysis by linear mixed-effects model showed that exposure was associated with a statistically significant decline in metabolite change of eicosapentaenoic acid [β(95% CI) = -0.013(-0.022 ≈ -0.004); p = 0.005], docosapentaenoic acid n3 [β(95% CI) = -0.010(-0.018 ≈ -0.002); p = 0.017], and docosapentaenoic acid n6 [β(95% CI) = -0.007(-0.013 ≈ -0.001); p = 0.021]. Pathway analysis identified an association of the unsaturated fatty acid pathway with exposure (p Study-2011 = 0.025; p Study-2012 = 0.021; p Combined = 0.009). The functional network built by these fatty acids and their interactive genes contained significant enrichment of genes associated with various diseases, including neoplasms, cardiovascular diseases, and lipid metabolism disorders. High-dose exposure of metal welding fumes decreases unsaturated fatty acids with an exposure-response relationship. This alteration in fatty acids is a potential biological mediator and biomarker for exposure-related health disorders.
Zeidler-Erdely, Patti C; Battelli, Lori A; Stone, Sam; Chen, Bean T; Frazer, David G; Young, Shih-Houng; Erdely, Aaron; Kashon, Michael L; Andrews, Ronnee; Antonini, James M
2011-02-01
Debate exists as to whether welding fume is carcinogenic, but epidemiological evidence suggests that welders are an at-risk population for development of lung cancer. Our objective was to expose, by inhalation, lung tumor susceptible (A/J) and resistant C57BL/6J (B6) mice to stainless steel (SS) welding fume containing carcinogenic metals and characterize the lung-inflammatory and tumorigenic response. Male mice were exposed to air or gas metal arc (GMA)-SS welding fume at 40 mg/m(3)×3 h/day for 6 and 10 days. At 1, 4, 7, 10, 14, and 28 days after 10 days of exposure, bronchoalveolar lavage (BAL) was done. Lung cytotoxicity, permeability, inflammatory cytokines, and cell differentials were analyzed. For the lung tumor study, gross tumor counts and histopathological changes were assessed in A/J mice at 78 weeks after 6 and 10 days of exposure. Inhalation of GMA-SS fume caused an early, sustained macrophage and lymphocyte response followed by a gradual neutrophil influx and the magnitudes of these differed between the mouse strains. Monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-2 (MIP-2), and tumor necrosis factor-α (TNF-α) were increased in both strains while the B6 also had increased interleukin-6 (IL-6) protein. BAL measures of cytotoxicity and damage were similar between the strains and significantly increased at all time points. Histopathology and tumorigenesis were unremarkable at 78 weeks. In conclusion, GMA-SS welding fume induced a significant and sustained inflammatory response in both mouse strains with no recovery by 28 days. Under our exposure conditions, GMA-SS exposure resulted in no significant tumor development in A/J mice.
Gube, Monika; Brand, Peter; Schettgen, Thomas; Bertram, Jens; Gerards, Kerstin; Reisgen, Uwe; Kraus, Thomas
2013-01-01
The objective of this study was to investigate whether there is a relationship between the external exposure dose of chromium and nickel caused by a metal active gas welding process with a solid high-alloyed steel welding wire and inner exposure of subjects. In order to perform welding fume exposure under controlled and standardized conditions, the investigations were conducted in the "Aachen Workplace Simulation Laboratory". To perform biological monitoring of chromium and nickel, blood and urine samples of 12 healthy male non-smokers who never worked as welders were collected before and after a 6-h exposure to ambient air (0 mg/m(3)) and to welding fumes of a metal active gas welding process once with a concentration of the welding fume of 1 mg/m(3) and once with a concentration of 2.5 mg/m(3). Although the internal exposure to chromium and nickel in this study was comparatively low, the subjects showed significantly increased concentrations of these metals in urine after exposure to welding fume compared to the values at baseline. Moreover, the observed increase was significantly dose dependent for both of the substances. For the biological monitoring of chromium and nickel in urine of subjects exposed to welding fumes, a dependency on exposure dose was seen under standardized conditions after a single exposure over a period of 6 h. Thus, this study contributes to a better understanding of the relationship between ambient and biological exposures from welding fumes and provides a good basis for evaluating future biological threshold values for these metals in welding occupation.
Characterization of Tungsten Inert Gas (TIG) Welding Fume Generated by Apprentice Welders.
Graczyk, Halshka; Lewinski, Nastassja; Zhao, Jiayuan; Concha-Lozano, Nicolas; Riediker, Michael
2016-03-01
Tungsten inert gas welding (TIG) represents one of the most widely used metal joining processes in industry. Its propensity to generate a greater portion of welding fume particles at the nanoscale poses a potential occupational health hazard for workers. However, current literature lacks comprehensive characterization of TIG welding fume particles. Even less is known about welding fumes generated by welding apprentices with little experience in welding. We characterized TIG welding fume generated by apprentice welders (N = 20) in a ventilated exposure cabin. Exposure assessment was conducted for each apprentice welder at the breathing zone (BZ) inside of the welding helmet and at a near-field (NF) location, 60cm away from the welding task. We characterized particulate matter (PM4), particle number concentration and particle size, particle morphology, chemical composition, reactive oxygen species (ROS) production potential, and gaseous components. The mean particle number concentration at the BZ was 1.69E+06 particles cm(-3), with a mean geometric mean diameter of 45nm. On average across all subjects, 92% of the particle counts at the BZ were below 100nm. We observed elevated concentrations of tungsten, which was most likely due to electrode consumption. Mean ROS production potential of TIG welding fumes at the BZ exceeded average concentrations previously found in traffic-polluted air. Furthermore, ROS production potential was significantly higher for apprentices that burned their metal during their welding task. We recommend that future exposure assessments take into consideration welding performance as a potential exposure modifier for apprentice welders or welders with minimal training. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Exposure to Cooking Fumes and Acute Reversible Decrement in Lung Functional Capacity.
Neghab, Masoud; Delikhoon, Mahdieh; Norouzian Baghani, Abbas; Hassanzadeh, Jafar
2017-10-01
Being exposed to cooking fumes, kitchen workers are occupationally at risk of multiple respiratory hazards. No conclusive evidence exists as to whether occupational exposure to these fumes is associated with acute and chronic pulmonary effects and symptoms of respiratory diseases. To quantify the exposure levels and evaluate possible chronic and acute pulmonary effects associated with exposure to cooking fumes. In this cross-sectional study, 60 kitchen workers exposed to cooking fumes and 60 unexposed employees were investigated. The prevalence of respiratory symptoms among these groups was determined through completion of a standard questionnaire. Pulmonary function parameters were also measured before and after participants' work shift. Moreover, air samples were collected and analyzed to quantify their aldehyde, particle, and volatile organic contents. The mean airborne concentrations of formaldehyde, acetaldehyde, and acrolein was 0.45 (SD 0.41), 0.13 (0.1), and 1.56 (0.41) mg/m 3 , respectively. The mean atmospheric concentrations of PM 1 , PM 2.5 , PM 7 , PM 10 , and total volatile organic compounds (TVOCs) was 3.31 (2.6), 12.21 (5.9), 44.16 (16.6), 57 (21.55) μg/m 3 , and 1.31 (1.11) mg/m 3 , respectively. All respiratory symptoms were significantly (p<0.05) more prevalent in exposed group. No significant difference was noted between the pre-shift mean of spirometry parameters of exposed and unexposed group. However, exposed workers showed cross-shift decrease in most spirometry parameters, significantly lower than the pre-shift values and those of the comparison group. Exposure to cooking fumes is associated with a significant increase in the prevalence of respiratory symptoms as well as acute reversible decrease in lung functional capacity.
Determination of the internal exposure hazard from plutonium work in an open front hood
NASA Astrophysics Data System (ADS)
Olson, Cheryl Lynn
Work with hazardous substances, such as radioactive material, can be done safely when engineered controls are used to maintain the worker effective dose below the International Commission on Radiological Protection ICRP 60 recommendation of 0.02 Sv/year and reduce the worker exposure to material to as low as reasonably achievable (ALARA). A primary engineered control used at a Los Alamos National Laboratory facility is the open-front hood. An open-front hood, also known as an open-front box, is a laboratory containment box that is fully enclosed except for a 15-cm opening along the front of the box. This research involved collection of the aerosol escaping an open-front hood while PuO2 sample digestion was simulated. Sodium chloride was used as a surrogate to mimic the behavior of PuO2. The NaCl aerosol was binned as a function of median aerodynamic diameter using a Micro-orifice Uniform Deposit Impactor (MOUDI, MSP Corporation, Shoreview, MN) cascade impactor. Using neutron activation analysis (NAA) to measure the mass of material in each of the nine bins of the MOUDI, the mass median diameter of the escaping aerosol was determined. Using the mass median diameter and the total mass of the particle distribution, dose was calculated using ICRP 60 methodology. Experimental conditions mimicked a stationary worker and a worker moving her hands in and out of the open front hood. Measurements were also done in the hood for comparison. The effect of the hands moving in and out of the box was modeled. Information necessary for Computational Fluid Dynamics (CFD) modeling is given, such as volumetric flow rates out of the open front hood and into the experimental room, detailed sketches of the experimental set-up, and energy provided by the hot plate and worker. This research is unique as it measures particle size distribution from routine working conditions. Current research uses tracer gases or describes non-routine conditions. It is important to have results that mimic routine conditions to allow for quantitative measurement of worker exposure and determination of the adequacy of the open front hood for this type of work. This work is important as it quantifies the effectiveness of the open front hood for controlling inhalation hazards. This information is crucial for managing the risk to workers. The mass median diameter of particles escaping the hood when a stationary worker sits in front of the hood is 0.54 +/- 3.7 mum. The mass median diameter of particles escaping the hood when a worker performs work in the hood is 0.35 +/- 5.1 mum. These particle sizes are in the range of those seen in the published liturature. (Raabe, et al., 1978; Dorrian and Bailey, 1995; and Cheng, et al., 2004) The effective dose from digestion of PuO2 in an open-front hood while a worker is moving her hands in and out of the hood was estimated to be 5 mSv. Based on the experimental error, this value could be low by a factor of 4. There was little difference between the dose calculated for a worker in motion and a stationary worker. The calculated dose while work was being performed is 5% higher. Comparison of these results to measured worker doses and continuous air monitoring results showed the experimental results may be somewhat higher. The lower limit of detection for urine bioassay is 0.002 Sv (Inkret, et al., 1999). Workers performing the activity mimicked in this experiment are routinely monitored and do not have measurable internal doses. The most likely reason for the high experimental results is the placement of the sample digestion apparatus. For this experiment, the material was placed 10 cm from the hood opening. In practice, the material is typically further back in the hood; placing the material further back in the hood likely decreases the amount of material escaping the hood. The cost-benefit analysis showed the use of the open-front hood as a reasonable protective measure. Although worker exposure may approach the ICRP limit, the cost of previously observed ergonomic injuries caused by work in a glove box is five thousand times greater than the dose received by the worker. Protective measures such as respiratory protection should be evaluated on a case by case basis to keep worker exposure as low as reasonably achievable.
Berlinger, B; Náray, M; Sajó, I; Záray, G
2009-06-01
In this work, welding fume samples were collected in a welding plant, where corrosion-resistant steel and unalloyed structural steel were welded by gas metal arc welding (GMAW) and manual metal arc welding (MMAW) techniques. The welding fumes were sampled with a fixed-point sampling strategy applying Higgins-Dewell cyclones. The following solutions were used to dissolve the different species of Ni and Mn: ammonium citrate solution [1.7% (m/v) diammonium hydrogen citrate and 0.5% (m/v) citric acid monohydrate] for 'soluble' Ni, 50:1 methanol-bromine solution for metallic Ni, 0.01 M ammonium acetate for soluble Mn, 25% acetic acid for Mn(0) and Mn(2+) and 0.5% hydroxylammonium chloride in 25% acetic acid for Mn(3+) and Mn(4+). 'Insoluble' Ni and Mn contents of the samples were determined after microwave-assisted digestion with the mixture of concentrated (cc). HNO(3), cc. HCl and cc. HF. The sample solutions were analysed by inductively coupled plasma quadrupole mass spectrometry and inductively coupled plasma atomic emission spectrometry. The levels of total Ni and Mn measured in the workplace air were different because of significant differences of the fume generation rates and the distributions of the components in the welding fumes between the welding processes. For quality control of the leaching process, dissolution of the pure stoichiometric Mn and Ni compounds and their mixtures weighing was investigated using the optimized leaching conditions. The results showed the adequacy of the procedure for the pure metal compounds. Based on the extraction procedures, the predominant oxidation states of Ni and Mn proved to be very different depending on the welding techniques and type of the welded steels. The largest amount of Mn in GMAW fumes were found as insoluble Mn (46 and 35% in case of corrosion-resistant steel and unalloyed structural steel, respectively), while MMAW fumes contain mainly soluble Mn, Mn(0) and Mn(2+) (78%) and Mn(3+) and Mn(4+) (54%) in case of corrosion-resistant steel and unalloyed structural steel, respectively. According to the results of the leaching procedures, GMAW fumes are rich in oxidic Ni (79%), while Ni compounds in welding fumes generated during MMAW are mainly in easily soluble form (44%). The crystalline phases were identified in each welding fume by X-ray powder diffraction (XRPD) technique as well. From the XRPD spectra, it is clear that GMAW fumes contain predominantly magnetite (FeFe(2)O(4)). In case of structural steel welding, there was a little amount of ferrite (alpha-Fe) also found. Welding fume generated during MMAW of structural steel contained a complex alkali-alkali earth fluoride phase (KCaF(3)-CaF(2)) and some magnetite and jakobsite (MnFe(2)O(4)). The XRPD results did not fully confirm the ones obtained from the extraction experiments. However, some results, for example the rate of soluble Ni and Mn compounds compared to the total, can be useful for further investigations of welding fumes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeMauro, Edward Paisley; Wagner, Justin L.; Beresh, Steven J.
High-speed, time-resolved particle image velocimetry with a pulse-burst laser was used to measure the gas-phase velocity upstream and downstream of a shock wave–particle curtain interaction at three shock Mach numbers (1.22, 1.40, and 1.45) at a repetition rate of 37.5 kHz. The particle curtain was formed from free-falling soda-lime particles resulting in volume fractions of 9% or 23% at mid-height, depending on particle diameter (106–125 and 300–355 μm, respectively). Following impingement by a shock wave, a pressure difference was created between the upstream and downstream sides of the curtain, which accelerated flow through the curtain. Jetting of flow through themore » curtain was observed downstream once deformation of the curtain began, demonstrating a long-term unsteady effect. Using a control volume approach, the unsteady drag on the curtain was estimated from velocity and pressure data. The drag imposed on the curtain has a strong volume fraction dependence with a prolonged unsteadiness following initial shock impingement. Additionally, the data suggest that the resulting pressure difference following the propagation of the reflected and transmitted shock waves is the primary component to curtain drag.« less
The silver lining of disposable sporicidal privacy curtains in an intensive care unit.
Kotsanas, Despina; Wijesooriya, W R P L I; Sloane, Tracy; Stuart, Rhonda L; Gillespie, Elizabeth E
2014-04-01
The environment is a well-known source of health care-acquired infection. Because of the known risk of contamination, patient privacy curtains require frequent changes to decrease the risk of spread from patients to curtain and visa versa. Fourteen disposable sporicidal privacy curtains were tested from December 2012 to June 2013 while hanging in a busy intensive care unit. Significant bacterial pathogens were identified and total bacteria enumerated as colony-forming units. Antimicrobial activity of curtain swatches was also tested against a range of bacteria in the laboratory. Measurements were recorded as zone of inhibition and contact inhibition. A cost analysis to replace standard curtains with disposable sporicidal curtains was also undertaken. Cultures grew low numbers of skin and environmental microorganisms with no methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, or Clostridium difficile detected. Vancomycin-resistant enterococci were recovered in very low numbers from 2 curtains where vancomycin-resistant enterococci-infected patients had been located. Privacy curtains demonstrated antimicrobial activity against C difficile and 13 additional bacterial pathogens. We conclude that disposable sporicidal privacy curtains are cost-effective and best replaced at 6 months in a high-risk area such as an intensive care unit. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.
DeMauro, Edward Paisley; Wagner, Justin L.; Beresh, Steven J.; ...
2017-06-08
High-speed, time-resolved particle image velocimetry with a pulse-burst laser was used to measure the gas-phase velocity upstream and downstream of a shock wave–particle curtain interaction at three shock Mach numbers (1.22, 1.40, and 1.45) at a repetition rate of 37.5 kHz. The particle curtain was formed from free-falling soda-lime particles resulting in volume fractions of 9% or 23% at mid-height, depending on particle diameter (106–125 and 300–355 μm, respectively). Following impingement by a shock wave, a pressure difference was created between the upstream and downstream sides of the curtain, which accelerated flow through the curtain. Jetting of flow through themore » curtain was observed downstream once deformation of the curtain began, demonstrating a long-term unsteady effect. Using a control volume approach, the unsteady drag on the curtain was estimated from velocity and pressure data. The drag imposed on the curtain has a strong volume fraction dependence with a prolonged unsteadiness following initial shock impingement. Additionally, the data suggest that the resulting pressure difference following the propagation of the reflected and transmitted shock waves is the primary component to curtain drag.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-18
... sound waves emanating from the pile, thereby reducing the sound energy. A confined bubble curtain... physically block sound waves and they prevent air bubbles from migrating away from the pile. The literature... acoustic pressure wave propagates out from a source, was estimated as so-called ``practical spreading loss...
25. Photocopy of engineering drawing. LC17B LONG TANK DELTA UPBUILD: ...
25. Photocopy of engineering drawing. LC-17B LONG TANK DELTA UPBUILD: MOBILE SERVICE TOWER, WEATHER CURTAINS SECTION 1 AND PLANS LEVELS 4 & 4A, 3, 2X, & 1A-ARCHITECTURAL, APRIL 1969. - Cape Canaveral Air Station, Launch Complex 17, Facility 28417, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL
USDA-ARS?s Scientific Manuscript database
The wine cellar mold, Zasmidium cellare, produces thick curtains of mycelia in cellars with high humidity, and its ability to metabolize volatile organic compounds is thought to improve air quality. Whether these abilities have affected its mitochondrial genome is not known. To fill this gap, its mi...
Hard metal exposures. Part 1: Observed performance of three local exhaust ventilation systems.
Guffey, S E; Simcox, N; Booth, D W; Hibbard, R; Stebbins, A
2000-04-01
Not every ventilation system performs as intended; much can be learned when they do not. The purpose of this study was to compare observed initial performance to expected levels for three saw-reconditioning shop ventilation systems and to characterize the changes in performance of the systems over a one-year period. These three local exhaust ventilation systems were intended to control worker exposures to cobalt, cadmium, and chromium during wet grinding, dry grinding, and welding/brazing activities. Prior to installation the authors provided some design guidance based on Industrial Ventilation, a Manual of Recommended Practice. However, the authors had limited influence on the actual installation and operation and no line authority for the systems. In apparent efforts to cut costs and to respond to other perceived needs, the installed systems deviated from the specifications used in pressure calculations in many important aspects, including adding branch ducts, use of flexible ducts, the choice of fans, and the construction of some hoods. After installation of the three systems, ventilation measurements were taken to determine if the systems met design specifications, and worker exposures were measured to determine effectiveness. The results of the latter will be published as a companion article. The deviations from design and maintenance failures may have adversely affected performance. From the beginning to the end of the study period the distribution of air flow never matched the design specifications for the systems. The observed air flows measured within the first month of installation did not match the predicated design air flows for any of the systems, probably because of the differences between the design and the installed system. Over the first year of operation, hood air flow variability was high due to inadequate cleaning of the sticky process materials which rapidly accumulated in the branch ducts. Poor distribution of air flows among branch ducts frequently produced individual hood air flows that were far below specified design levels even when the total air flow through that system was more than adequate. To experienced practitioners, it is not surprising that deviations from design recommendations and poor maintenance would be associated with poor system performance. Although commonplace, such experiences have not been documented in peer-reviewed publications to date. This publication is a first step in providing that documentation.
Exposure to cyclic anhydrides in welding: a new allergen-chlorendic anhydride.
Pfäffli, Pirkko; Hämeilä, Mervi; Keskinen, Helena; Wirmoila, Ritva
2002-11-01
Respiratory effects associated with welding fumes have been manifested in welders as occupational asthma. Previous studies have concerned mainly the effects of metal fume exposure, although it has also been suggested that asthma may develop as a result of exposure to contaminants generated from painted metals. To determine whether welding fumes contain irritating and sensitizing anhydrides, air samples were collected during the repair welding of forest harvesters, which were painted with chlorinated polyester paint. Samples were collected with an assembly of a spiral glass trap inserted between a filter holder with a Teflon filter and a Tenax sampling tube. Sample analyses were with GC-MS and GC-ECD. Sensitizing anhydrides released from the paint into the air were primarily chlorendic anhydride (<2-44 microg/m(3)) and phthalic anhydride (11-21 microg/m(3)). Hydrogen chloride (HCl) and hexachlorocyclopentadiene were also found. Airborne HCl was measured with Dräger tubes. Since paint films are electrical insulators, the film around the welding seam was removed before arc welding. Removal of paint with an abrasive wheel caused the least exposure to HCl (<0.5 ppm) in contrast to burning with a gas fuel torch, (HCl approximately 5 ppm). HCl exposure was the highest (<0.5-20 ppm) during welding. It is recommended that dry paint coating be removed from an area around the seam with an abrasive wheel, not by burning, before welding.
Dumouchelle, Denise H.
2006-01-01
Many home sewage-treatment systems (HSTS) in Ohio use curtain or perimeter drains to depress the level of the subsurface water in and around the systems. These drains could possibly intercept partially untreated wastewater and release potential pathogens to ground-water and surface-water bodies. The quality of water in curtain drains from two different HSTS designs in Medina County, Ohio, was investigated using several methods. Six evaporation-transpiration-absorption (ETA) and five leach-line (LL) systems were investigated by determining nutrient concentrations, chloride/bromide ratios (Cl/Br), Escherichia coli (E. coli ) concentrations, coliphage genotyping, and genetic fingerprinting of E. coli. Water samples were collected at 11 sites and included samples from curtain drains, septic tanks, and residential water wells. Nitrate concentrations in the curtain drains ranged from 0.03 to 3.53 mg/L (milligrams per liter), as N. Concentrations of chloride in 10 of the 11 curtain drains ranged from 5.5 to 21 mg/L; the chloride concentration in the eleventh curtain drain was 340 mg/L. Bromide concentrations in 11 curtain drains ranged from 0.01 to 0.22 mg/L. Cl/Br ratios ranged from 86 to 2,000. F-specific coliphage were not found in any curtain-drain samples. Concentrations of E. coli in the curtain drains ranged from 1 to 760 colonies per 100 milliliters. The curtain-drain water-quality data were evaluated to determine whether HSTS-derived water was present in the curtain drains. Nutrient concentrations were too low to be of use in the determination. The Cl/Br ratios appear promising. Coliphage was not detected in the curtain drains, so genotyping could not be attempted. E. coli concentrations in the curtain drains were all less than those from the corresponding HSTS; only one sample exceeded the Ohio secondary-contact water-quality standard. The genetic fingerprinting data were inconclusive because multiple links between unrelated sites were found. Although the curtain-drain samples from the ETA systems showed somewhat more evidence of the presence of HSTS water than did the LL systems, most of the approaches were inconclusive by themselves. The best evidence of HSTS water, from the Cl/Br ratios, indicates that the water in 10 of the 11 curtain drains, at both HSTS types, was a mixture of dilute ground water and HSTS-derived water; the 11th drain also show some effects of the HSTS, although road salt-affected water may be present. Therefore, it appears that there is no difference between the ETA and LL systems with respect to the water quality in curtain drains.
Baek, Yoon Jeong; Jung, Dahee; Son, Su-Young; Lee, Joo-Young
2018-03-01
The purpose of this study was to evaluate physiological and subjective responses while wearing the Shikoro-type helmet for firefighters when compared to typical helmets. Eight firefighters conducted a 30-min exercise at a 5 km h -1 in three helmet conditions at an air temperature of 32 °C with 70%RH. The results showed that no significant differences in rectal, mean skin temperature and physiological strain index among the three conditions were found during exercise and recovery. Skin temperatures on the cheek, ear and neck during exercise were significantly lower for the Shikoro-type condition (p < 0.05), but forehead temperature was greater for the Shikoro-type helmet when compared to the other conditions (p < 0.05). Statistical differences in thermal sensation and thermal comfort for overall and local body regions were not found among the three conditions. These results imply that the Shikoro-type helmet had local advantages in reducing skin temperatures on the face and neck. Practitioner Summary: Firefighters wear their helmet with its hood to protect the head and neck but a Shikoro type helmet has no fire protective hood. This study aimed to evaluate the comfort function of Shikoro helmet along with typical helmets. The results demonstrated thermal benefits of the Shikoro helmet on the head.
Carbon Dioxide Blast/Vacuum Demilitarization
1992-08-01
through a venturi at the opening of the nozzle. The nozzle accelerates the pellets up to supersonic speeds. CONCEPT ORIGINATION: The concept for a...sent td the treatment plant. The kettle also requires a hood to capture the vapor rising from it, which uses a sophisticated air scrubber to remove