40 CFR 52.69 - Original identification of plan section.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Jefferson County Board of Health Air Pollution Control Rules and Regulations, which became effective June 14... Implementation Plan submitted on March 21, 1972, by the Alabama Air Pollution Control Commission. (2) Compliance schedules submitted on April 18, 1972, by the Alabama Air Pollution Control Commission. (3) Clarifying...

Ambient air quality programmes for health impact assessment in the WHO European region.

PubMed

Mücke, H G

2000-06-01

An important aim of air quality assessment is to provide information about population exposure and health impact assessment. Numerous epidemiological studies have already shown that exposure to excessive levels of ambient air pollutants are associated with either acute or chronic health effects. Until recently, the adequacy of monitoring population exposure in relation to quantitative assessment of health effects of air pollution was rarely considered in ambient air monitoring strategies. This made the formulation of health-related recommendations to risk management difficult and weakens preventive and other measures to reduce adverse health effects of air pollution. To improve local and national capacities for health impact assessment, the European Centre for Environment and Health of the World Health Organization has prepared methodology guidelines concerning selected aspects of air monitoring. The WHO Collaborating Centre for Air Quality Management and Air Pollution Control support efforts in line with international programmes on quality assurance and control for Europe.

A model for active control of helicopter air resonance in hover and forward flight

NASA Technical Reports Server (NTRS)

Takahashi, M. D.; Friedmann, P. P.

1988-01-01

A coupled rotor/fuselage helicopter analysis is presented. The accuracy of the model is verified by comparing it with the experimental data. The sensitivity of the open loop damping of the unstable air resonance mode to such modeling effects as blade torsional flexibility, unsteady aerodynamics, forward flight, periodic terms, and trim solution is illustrated by numerous examples. Subsequently, the model is used in conjunction with linear optimal control theory to stabilize the air resonance mode. The influence of the modeling effects mentioned before on active air resonance control is then investigated.

Air Pollution and Control Legislation in India

NASA Astrophysics Data System (ADS)

P Bhave, Prashant; Kulkarni, Nikhil

2015-09-01

Air pollution in urban areas arises from multiple sources, which may vary with location and developmental activities. Anthropogenic activities as rampant industrialization, exploitation and over consumption of natural resources, ever growing population size are major contributors of air pollution. The presented review is an effort to discuss various aspects of air pollution and control legislation in India emphasizing on the history, present scenario, international treaties, gaps and drawbacks. The review also presents legislative controls with judicial response to certain landmark judgments related to air pollution. The down sides related to enforcement mechanism for the effective implementation of environmental laws for air pollution control have been highlighted.

40 CFR 60.2977 - What definitions must I know?

Code of Federal Regulations, 2011 CFR

2011-07-01

... approved and effective State section 111(d)/129 plans, the Director of the State air pollution control..., an employee of the EPA, the Director of the State air pollution control agency, or employee of the State air pollution control agency to whom the authority has been delegated by the Administrator of the...

40 CFR 60.3078 - What definitions must I know?

Code of Federal Regulations, 2011 CFR

2011-07-01

... approved and effective State section 111(d)/129 plans, the Director of the State air pollution control..., an employee of the EPA, the Director of the State air pollution control agency, or employee of the State air pollution control agency to whom the authority has been delegated by the Administrator of the...

Biologic Effects of Atmospheric Pollutants: Asbestos - The Need For and Feasibility of Air Pollution Controls

EPA Pesticide Factsheets

This 1971 report sets forth in a well-organized fashion the currently available information on asbestos as an air pollutant, with special attention to sources health effects, measurements, and feasibility of control.

Causes of Indoor Air Quality Problems in Schools: Summary of Scientific Research. Revised Edition.

ERIC Educational Resources Information Center

Bayer, Charlene W.; Crow, Sidney A.; Fischer, John

Understanding the primary causes of indoor air quality (IAQ) problems and how controllable factors--proper heating, ventilation and air-conditioning (HVAC) system design, allocation of adequate outdoor air, proper filtration, effective humidity control, and routine maintenance--can avert problems may help all building owners, operators, and…

Assessment of long-term and large-scale even-odd license plate controlled plan effects on urban air quality and its implication

NASA Astrophysics Data System (ADS)

Zhao, Suping; Yu, Ye; Qin, Dahe; Yin, Daiying; He, Jianjun

2017-12-01

To solve traffic congestion and to improve urban air quality, long-lasting and large-scale even-odd license plate controlled plan was implemented by local government during 20 November to 26 December 2016 in urban Lanzhou, a semi-arid valley city of northwest China. The traffic control measures provided an invaluable opportunity to evaluate its effects on urban air quality in less developed cities of northwest China. Based on measured simultaneously air pollutants and meteorological parameters, the abatement of traffic-related pollutants induced by the implemented control measures such as CO, PM2.5 and PM10 (the particulate matter with diameter less than 2.5 μm and 10 μm) concentrations were firstly quantified by comparing the air quality data in urban areas with those in rural areas (uncontrolled zones). The concentrations of CO, NO2 from motor vehicles and fine particulate matter (PM2.5) were shown to have significant decreases of 15%-23% during traffic control period from those measured before control period with hourly maximum CO, PM2.5, and NO2/SO2 reduction of 43%, 35% and 141.4%, respectively. The influence of the control measures on AQI (air quality index) and ozone was less as compared to its effect on other air pollutants. Therefore, to alleviate serious winter haze pollution in China and to protect human health, the stringent long-term and large-scale even-odd license plate controlled plan should be implemented aperiodically in urban areas, especially for the periods with poor diffusion conditions.

Automation in future air traffic management: effects of decision aid reliability on controller performance and mental workload.

PubMed

Metzger, Ulla; Parasuraman, Raja

2005-01-01

Future air traffic management concepts envisage shared decision-making responsibilities between controllers and pilots, necessitating that controllers be supported by automated decision aids. Even as automation tools are being introduced, however, their impact on the air traffic controller is not well understood. The present experiments examined the effects of an aircraft-to-aircraft conflict decision aid on performance and mental workload of experienced, full-performance level controllers in a simulated Free Flight environment. Performance was examined with both reliable (Experiment 1) and inaccurate automation (Experiment 2). The aid improved controller performance and reduced mental workload when it functioned reliably. However, detection of a particular conflict was better under manual conditions than under automated conditions when the automation was imperfect. Potential or actual applications of the results include the design of automation and procedures for future air traffic control systems.

Evaluating Information Assurance Control Effectiveness on an Air Force Supervisory Control and Data Acquisition (SCADA) System

DTIC Science & Technology

2011-03-01

Byres, E. J., Lowe, J. (2004). The Myths and facts behind cyber security risks for industrial control systems . Berlin, Germany: VDE 2004 Congress...ACQUISITION (SCADA) SYSTEM THESIS Jason R. Nielsen, Major, USAF AFIT/GCO/ENG/11-10 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE...DATA ACQUISITION (SCADA) SYSTEM THESIS Presented to the Faculty Department of Electrical and Computer Engineering Graduate School of

Decision support automation research in the en route air traffic control environment

DOT National Transportation Integrated Search

2002-01-01

This study examined the effect of automated decision support on Certified Professional Controller (CPC) behavior. : Sixteen CPCs from Air Route Traffic Control Centers participated in human-in-the-loop simulations. CPCs controlled : two levels of tra...

Stress in air traffic controllers : effects of ARTS-III

DOT National Transportation Integrated Search

1976-11-01

Physiological, biochemical, and psychological assessments of stress in air traffic controllers were made at Los Angeles (LAX) and Oakland (OAK) Terminal Radar Approach Control (TRACON) facilities before and after installation of Automated Radar Termi...

Problems in air traffic management. I., Longitudinal prediction of effectiveness of air traffic controllers.

DOT National Transportation Integrated Search

1961-12-01

Current (1961) job performance evaluations and medical history data were obtained for 149 of 197 men trained in air traffic control work in 1956. Evaluations of psychological test and biographical data collected at the time they went through training...

Caging, but not air deprivation, slows tadpole growth and development in the amphibian Xenopus laevis.

PubMed

Rose, Christopher S

2014-08-01

Xenopus laevis tadpoles raised in submerged cages in normoxic water develop more slowly than tadpoles raised with access to air. This study distinguishes between the effects of being caged and being deprived access to air on development and growth. Tadpoles were raised in high and low density control tanks and in cages in the same tank that were either completely submerged or with the top exposed to air. Experiments were repeated with the cages in different positions relative to the air stones and with and without the water flow from air stones supplemented with a pump. Whereas caging tadpoles has a large effect on their development and growth, additionally depriving them of air has a small effect and this effect can be removed by optimizing water flow through the cage. The effect of caging, though significant in this study, is small compared to the variation in growth and developmental rates that is commonly encountered within and among controls in lab studies. Caging effects can also be diminished by optimizing rearing conditions and/or having exceptionally vigorous tadpoles. The effects of air deprivation and caging thus pose less of a problem for experimenting on air-deprived (AD) and air-restored Xenopus tadpoles than their inherent variability in growth and developmental rates and their susceptibility to growth and developmental arrest. Further, the effect of air deprivation in this air-breathing amphibian does not pose a conflict with evolutionary hypotheses for lung loss involving lengthening of the larval period and delay in the onset of air breathing. © 2014 Wiley Periodicals, Inc.

Implications of alternative assumptions regarding future air pollution control in scenarios similar to the Representative Concentration Pathways

NASA Astrophysics Data System (ADS)

Chuwah, Clifford; van Noije, Twan; van Vuuren, Detlef P.; Hazeleger, Wilco; Strunk, Achim; Deetman, Sebastiaan; Beltran, Angelica Mendoza; van Vliet, Jasper

2013-11-01

The uncertain, future development of emissions of short-lived trace gases and aerosols forms a key factor for future air quality and climate forcing. The Representative Concentration Pathways (RCPs) only explore part of this range as they all assume that worldwide ambitious air pollution control policies will be implemented. In this study, we explore how different assumptions on future air pollution policy and climate policy lead to different concentrations of air pollutants for a set of RCP-like scenarios developed using the IMAGE model. These scenarios combine low and high air pollution variants of the scenarios with radiative forcing targets in 2100 of 2.6 W m-2 and 6.0 W m-2. Simulations using the global atmospheric chemistry and transport model TM5 for the present-day climate show that both climate mitigation and air pollution control policies have large-scale effects on pollutant concentrations, often of similar magnitude. If no further air pollution policies would be implemented, pollution levels could be considerably higher than in the RCPs, especially in Asia. Air pollution control measures could significantly reduce the warming by tropospheric ozone and black carbon and the cooling by sulphate by 2020, and in the longer term contribute to enhanced warming by methane. These effects tend to cancel each other on a global scale. According to our estimates the effect of the worldwide implementation of air pollution control measures on the total global mean direct radiative forcing in 2050 is +0.09 W m-2 in the 6.0 W m-2 scenario and -0.16 W m-2 in the 2.6 W m-2 scenario.

Study on the relationship between the opening of environmental tax and the prevention and control of air pollution in China

NASA Astrophysics Data System (ADS)

Gao, Guilin; Wang, Tianyi

2018-03-01

This article systematically expounds the status quo and sources of air pollution, the experience of foreign environmental tax policy, the advantages and disadvantages of environmental taxes levied in our country through literature research, historical analysis and comparative analysis and put forward recommendations on tax policy of prevention and control of air pollution by combining with the specific national conditions in our country. As one of the basic means of national macro-control, the tax policy is the major countermeasure that cannot be ignored in the prevention and control of air pollution. Studying the tax policy of prevention and control of air pollution will help to effectively control air pollution, develop a green economy and recycle economy and achieve the goal of improving environmental quality.

Effectiveness of in-room air filtration and dilution ventilation for tuberculosis infection control.

PubMed

Miller-Leiden, S; Lobascio, C; Nazaroff, W W; Macher, J M

1996-09-01

Tuberculosis (TB) is a public health problem that may pose substantial risks to health care workers and others. TB infection occurs by inhalation of airborne bacteria emitted by persons with active disease. We experimentally evaluated the effectiveness of in-room air filtration systems, specifically portable air filters (PAFs) and ceiling-mounted air filters (CMAFs), in conjunction with dilution ventilation, for controlling TB exposure in high-risk settings. For each experiment, a test aerosol was continuously generated and released into a full-sized room. With the in-room air filter and room ventilation system operating, time-averaged airborne particle concentrations were measured at several points. The effectiveness of in-room air filtration plus ventilation was determined by comparing particle concentrations with and without device operation. The four PAFs and three CMAFs we evaluated reduced room-average particle concentrations, typically by 30% to 90%, relative to a baseline scenario with two air-changes per hour of ventilation (outside air) only. Increasing the rate of air flow recirculating through the filter and/or air flow from the ventilation did not always increase effectiveness. Concentrations were generally higher near the emission source than elsewhere in the room. Both the air flow configuration of the filter and its placement within the room were important, influencing room air flow patterns and the spatial distribution of concentrations. Air filters containing efficient, but non-high efficiency particulate air (HEPA) filter media were as effective as air filters containing HEPA filter media.

Effectiveness of In-Room Air Filtration and Dilution Ventilation for Tuberculosis Infection Control.

PubMed

Miller-Leiden, S; Lohascio, C; Nazaroff, W W; Macher, J M

1996-09-01

Tuberculosis (TB) is a public health problem that may pose substantial risks to health care workers and others. TB infection occurs by inhalation of airborne bacteria emitted by persons with active disease. We experimentally evaluated the effectiveness of in-room air filtration systems, specifically portable air filters (PAFs) and ceiling-mounted air filters (CMAFs), in conjunction with dilution ventilation, for controlling TB exposure in high-risk settings. For each experiment, a test aerosol was continuously generated and released into a full-sized room. With the in-room air filter and room ventilation system operating, time-averaged airborne particle concentrations were measured at several points. The effectiveness of in-room air filtration plus ventilation was determined by comparing particle concentrations with and without device operation. The four PAFs and three CMAFs we evaluated reduced room-average particle concentrations, typically by 30% to 90%, relative to a baseline scenario with two air-changes per hour of ventilation (outside air) only. Increasing the rate of air flow recirculating through the filter and/or air flow from the ventilation did not always increase effectiveness. Concentrations were generally higher near the emission source than elsewhere in the room. Both the air flow configuration of the filter and its placement within the room were important, influencing room air flow patterns and the spatial distribution of concentrations. Air filters containing efficient, but non-high efficiency particulate air (HEPA) filter media were as effective as air filters containing HEPA filter media.

Incubator temperature control: effects on the very low birthweight infant.

PubMed Central

Ducker, D A; Lyon, A J; Ross Russell, R; Bass, C A; McIntosh, N

1985-01-01

We studied temperature stability in 22 infants of birthweight less than 1500 g in the first four days of life. Infants were nursed in incubators using either air mode control or skin temperature servo control. Data were collected continuously using a computer linked monitoring system. Skin temperature control resulted in a less stable thermal environment than air mode control. Increased thermal stability in the incubator on air mode control may well be beneficial, particularly to sick, very low birthweight infants. PMID:4062342

Effects of air vessel on water hammer in high-head pumping station

NASA Astrophysics Data System (ADS)

Wang, L.; Wang, F. J.; Zou, Z. C.; Li, X. N.; Zhang, J. C.

2013-12-01

Effects of air vessel on water hammer process in a pumping station with high-head were analyzed by using the characteristics method. The results show that the air vessel volume is the key parameter that determines the protective effect on water hammer pressure. The maximum pressure in the system declines with increasing air vessel volume. For a fixed volume of air vessel, the shape of air vessel and mounting style, such as horizontal or vertical mounting, have little effect on the water hammer. In order to obtain good protection effects, the position of air vessel should be close to the outlet of the pump. Generally, once the volume of air vessel is guaranteed, the water hammer of a entire pipeline is effectively controlled.

How do Air Traffic Controllers Use Automation and Tools Differently During High Demand Situations?

NASA Technical Reports Server (NTRS)

Kraut, Joshua M.; Mercer, Joey; Morey, Susan; Homola, Jeffrey; Gomez, Ashley; Prevot, Thomas

2013-01-01

In a human-in-the-loop simulation, two air traffic controllers managed identical airspace while burdened with higher than average workload, and while using advanced tools and automation designed to assist with scheduling aircraft on multiple arrival flows to a single meter fix. This paper compares the strategies employed by each controller, and investigates how the controllers' strategies change while managing their airspace under more normal workload conditions and a higher workload condition. Each controller engaged in different methods of maneuvering aircraft to arrive on schedule, and adapted their strategies to cope with the increased workload in different ways. Based on the conclusions three suggestions are made: that quickly providing air traffic controllers with recommendations and information to assist with maneuvering and scheduling aircraft when burdened with increased workload will improve the air traffic controller's effectiveness, that the tools should adapt to the strategy currently employed by a controller, and that training should emphasize which traffic management strategies are most effective given specific airspace demands.

A simulation study of the effects of communication delay on air traffic control

DOT National Transportation Integrated Search

1990-09-01

This study was conducted to examine the impacts of voice communications delays : characteristic of Voice Switching and Control System (VSCS) and satellite : communications systems on air traffic system performance, controller stress : and workload, a...

Verification of Energy Reduction Effect through Control Optimization of Supply Air Temperature in VRF-OAP System

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

Lee, Je; Yoon, Hyun; Im, Piljae

This paper developed an algorithm that controls the supply air temperature in the variable refrigerant flow (VRF), outdoor air processing unit (OAP) system, according to indoor and outdoor temperature and humidity, and verified the effects after applying the algorithm to real buildings. The VRF-OAP system refers to a heating, ventilation, and air conditioning (HVAC) system to complement a ventilation function, which is not provided in the VRF system. It is a system that supplies air indoors by heat treatment of outdoor air through the OAP, as a number of indoor units and OAPs are connected to the outdoor unit inmore » the VRF system simultaneously. This paper conducted experiments with regard to changes in efficiency and the cooling capabilities of each unit and system according to supply air temperature in the OAP using a multicalorimeter. Based on these results, an algorithm that controlled the temperature of the supply air in the OAP was developed considering indoor and outdoor temperatures and humidity. The algorithm was applied in the test building to verify the effects of energy reduction and the effects on indoor temperature and humidity. Loads were then changed by adjusting the number of conditioned rooms to verify the effect of the algorithm according to various load conditions. In the field test results, the energy reduction effect was approximately 15–17% at a 100% load, and 4–20% at a 75% load. However, no significant effects were shown at a 50% load. The indoor temperature and humidity reached a comfortable level.« less

Verification of Energy Reduction Effect through Control Optimization of Supply Air Temperature in VRF-OAP System

DOE PAGES

Lee, Je; Yoon, Hyun; Im, Piljae; ...

2017-12-27

This paper developed an algorithm that controls the supply air temperature in the variable refrigerant flow (VRF), outdoor air processing unit (OAP) system, according to indoor and outdoor temperature and humidity, and verified the effects after applying the algorithm to real buildings. The VRF-OAP system refers to a heating, ventilation, and air conditioning (HVAC) system to complement a ventilation function, which is not provided in the VRF system. It is a system that supplies air indoors by heat treatment of outdoor air through the OAP, as a number of indoor units and OAPs are connected to the outdoor unit inmore » the VRF system simultaneously. This paper conducted experiments with regard to changes in efficiency and the cooling capabilities of each unit and system according to supply air temperature in the OAP using a multicalorimeter. Based on these results, an algorithm that controlled the temperature of the supply air in the OAP was developed considering indoor and outdoor temperatures and humidity. The algorithm was applied in the test building to verify the effects of energy reduction and the effects on indoor temperature and humidity. Loads were then changed by adjusting the number of conditioned rooms to verify the effect of the algorithm according to various load conditions. In the field test results, the energy reduction effect was approximately 15–17% at a 100% load, and 4–20% at a 75% load. However, no significant effects were shown at a 50% load. The indoor temperature and humidity reached a comfortable level.« less

Stress, anxiety, and the air traffic control specialist : some conclusions from a decade of research.

DOT National Transportation Integrated Search

1980-09-01

This paper summarizes a decade of research evaluating possible stress effects of work on Air Traffic Control Specialists (ATCSs).Studies were conducted at a variety of large and small air traffic facilities. A visit of several days to each facility w...

HVAC SYSTEMS AS A TOOL IN CONTROLLING INDOOR AIR QUALITY: A LITERATURE REVIEW

EPA Science Inventory

The report gives results of a review of literature on the use of heating, ventilating, and air-conditioning (HVAC) systems to control indoor air quality (IAQ). Although significant progress has been made in reducing the energy consumption of HVAC systems, their effect on indoor a...

OZONE AMBIENT AIR QUALITY STANDARD HAS BENEFICIAL EFFECT ON PONDEROSA PINE IN CALIFORNIA

EPA Science Inventory

Ambient air quality standards and control strategies are implemented to protect humans and vegetation from adverse effects. However, to date there has not been a simple and objective method to determine if the standards and resultant control strategies have reduced O3 impacts on ...

Effect of evaporation of solvents from one-step, self-etching adhesives.

PubMed

Furuse, Adilson Yoshio; Peutzfeldt, Anne; Asmussen, Erik

2008-02-01

To investigate whether and to what extent the bonding capacity of one-step, self-etching adhesives is influenced by the degree to which solvent is evaporated. Seven one-step, self-etching adhesives were tested (Adper Prompt L-Pop, Clearfil S3 Bond, Futurabond NR, G-Bond, Hybrid Bond, iBond, Xeno III). The variation in degree of evaporation was obtained by varying the duration of the air-blowing step. The duration required to immobilize the adhesive layer, as established in a pilot study, was used as control. Two experimental air-blowing durations, shorter (half the control duration) and longer (double the control duration) than the control duration, were chosen. The resin composite Herculite XRV was bonded to flat human dentin surfaces treated with one of the adhesives following manufacturer's instructions, except for the air-blowing duration after application. After being stored in water at 37 degrees C for 1 week, the bonded specimens were broken in shear. Failure modes were evaluated under stereomicroscope. Air-blowing duration and brand of adhesive both had an effect on shear bond strength. An interaction was found between adhesive and air-blowing duration. Some adhesives were insensitive to variations in air-drying duration, but in general, air-blowing durations shorter than the control duration produced lower shear bond strengths. Significant effects of adhesive and air-blowing duration were also detected in relation to failure mode. More adhesive failures were observed with shorter air-blowing durations. A significant negative correlation between number of adhesive failures and bond strength was found. On the basis of this in vitro study, it may be concluded that the one-step, self-etching adhesives evaluated were sensitive to degree of evaporation of the solvents.

Modeling validation and control analysis for controlled temperature and humidity of air conditioning system.

PubMed

Lee, Jing-Nang; Lin, Tsung-Min; Chen, Chien-Chih

2014-01-01

This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14 °C, 0006 kg(w)/kg(da) in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System

PubMed Central

Lee, Jing-Nang; Lin, Tsung-Min

2014-01-01

This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14°C, 0006 kgw/kgda in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system. PMID:25250390

Human factors for air traffic control specialists : a user's manual for your brain

DOT National Transportation Integrated Search

1999-11-01

This document presents the findings of human factors research and other information useful to air traffic control specialists in a succinct and easy-to-read format. Topics include: controller-pilot voice communications, memory, fatigue and the effect...

Thermal comfort, perceived air quality, and cognitive performance when personally controlled air movement is used by tropically acclimatized persons.

PubMed

Schiavon, S; Yang, B; Donner, Y; Chang, V W-C; Nazaroff, W W

2017-05-01

In a warm and humid climate, increasing the temperature set point offers considerable energy benefits with low first costs. Elevated air movement generated by a personally controlled fan can compensate for the negative effects caused by an increased temperature set point. Fifty-six tropically acclimatized persons in common Singaporean office attire (0.7 clo) were exposed for 90 minutes to each of five conditions: 23, 26, and 29°C and in the latter two cases with and without occupant-controlled air movement. Relative humidity was maintained at 60%. We tested thermal comfort, perceived air quality, sick building syndrome symptoms, and cognitive performance. We found that thermal comfort, perceived air quality, and sick building syndrome symptoms are equal or better at 26°C and 29°C than at the common set point of 23°C if a personally controlled fan is available for use. The best cognitive performance (as indicated by task speed) was obtained at 26°C; at 29°C, the availability of an occupant-controlled fan partially mitigated the negative effect of the elevated temperature. The typical Singaporean indoor air temperature set point of 23°C yielded the lowest cognitive performance. An elevated set point in air-conditioned buildings augmented with personally controlled fans might yield benefits for reduced energy use and improved indoor environmental quality in tropical climates. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of public health interventions on industrial emissions and ambient air in Cartagena, Spain.

PubMed

Cirera, Lluís; Rodríguez, Miguel; Giménez, Joaquín; Jiménez, Enrique; Saez, Marc; Guillén, José-Jesús; Medrano, José; Martínez-Victoria, María-Aurelia; Ballester, Ferran; Moreno-Grau, Stella; Navarro, Carmen

2009-03-01

Ten years of public health interventions on industrial emissions to clean air were monitored for the Mediterranean city of Cartagena. During the 1960s, a number of large chemical and non-ferrous metallurgical factories were established that significantly deteriorated the city's air quality. By the 1970s, the average annual air concentration of sulfur dioxide (SO2) ranged from 200 to 300 microg/m3 (standard conditions units). In 1979, the Spanish government implemented an industrial intervention plan to improve the performance of factories and industrial air pollution surveillance. Unplanned urban development led to residential housing being located adjacent to three major factories. Factory A produced lead, factory B processed zinc from ore concentrates, and factory C produced sulfuric acid and phosphates. This, in combination with the particular abrupt topography and frequent atmospheric thermal inversions, resulted in the worsening of air quality and heightening concern for public health. In 1990, the City Council authorized the immediate intervention at these factories to reduce or shut down production if ambient levels of SO2 or total suspended particles (TSP) exceeded a time-emission threshold in pre-established meteorological contexts. The aim of this research was to assess the appropriateness and effectiveness of the intervention plan implemented from 1992 to 2001 to abate industrial air pollution. The maximum daily 1-h ambient air level of SO2, NO2, and TSP pollutants was selected from one of the three urban automatic stations, designed to monitor ambient air quality around industrial emissions sources. The day on which an intervention took place to reduce and/or interrupt industrial production by factory and pollutant was defined as a control day, and the day after an intervention as a post-control day. To assess the short-term intervention effect on air quality, an ecological time series design was applied, using regression analysis in generalized additive models, focusing on day-to-day variations of ambient air pollutants levels. Two indicators were estimated: (a) appropriateness, the ratio between mean levels of the pollutant for control days versus the other days, and (b) effectiveness, the ratio between mean levels of the pollutant for post-control days versus the other days. Ratios in regression analyses were adjusted for trend, seasonality, temperature, humidity and atmospheric pressure, calendar day, and special events as well as the other pollutants. A total of 702 control days were made on the factories' industrial production during the 10-year period. Fifteen reductions and five shutdown control days took place at factory A for ambient air SO2. At factory B, more controls were carried out for the SO2 pollutant in the years 1992-1993 and 1997. At factory C, the control days for SO2 decreased from 59 reductions and 14 shutdowns to a minimum from 1995 onwards, whereas the controls on TSP were more frequent, reaching a maximum of 99 reductions and 47 shutdowns in the last year. SO2 ambient air mean levels ranged from 456 to 699 microg/m(3) among factories on reduction control days and between 624 and 1,010 microg/m(3) on shutdown days. The TSP ambient air mean levels were 428 and 506 microg/m(3) on reduction and shutdown days, respectively. For all types of control days and factories, a mean ratio of 104% (95% confidence interval [CI] 88 to 121) in SO(2) levels was obtained and a mean ratio of 67% (95% CI 59 to 75) in TSP levels. Post-control days at all factories showed a mean ratio of -16% (95% CI -7 to -24) in SO(2) levels and a mean ratio of -13% (95% CI -7 to -19) in TSP levels. Interventions on industrial production based on the urban SO(2) and TSP ambient air levels were justified by the high concentrations detected. The best assessment of the interventions' effectiveness would have been to utilize the ambient air pollutant concentration readings from the entire time of the production shutdowns or reductions; however, the daily hourly maximum turned out to be a useful indicator because of meteorological factors influencing the diurnal concentration profile. A substantial number of interventions were carried out from 1 to 3 AM: , when vehicular traffic was minimum. On the other hand, atmospheric stability undergoes diurnal cycling in the autumn-winter period due to thermal inversion, which reaches maximum levels around daybreak. Therefore, this increases the ambient air levels and justified the interventions carried out at daybreak in spite of the traffic influence. All the interventions for SO(2) and TSP were carried out when the measured ambient air levels of pollutants were exceeded, which shows the appropriateness of the intervention program. This excess was greater when intervening on SO(2) than on the TSP levels. For both ambient air levels of SO(2) and TSP, significant drops in air pollution were achieved from all three factories following activity reductions. The production shutdown controls were very effective, because they returned excess levels, higher than in the reduction controls, to everyday mean values. The Cartagena City observational system of intermittent control has proven to effectively reduce industrial emissions' impact on ambient air quality. This experienced model approach could serve well in highly polluted industrial settings. From a public health perspective, studies are needed to assess that the industrial interventions to control air pollution were related to healthier human populations. Legislation was needed to allow the public administration to take direct actions upon the polluting industries.

The advantages and disadvantages of centralized control of air power at operational level

NASA Astrophysics Data System (ADS)

Arisoy, Uǧur

2014-05-01

People do not want to see and hear a war. In today's world, if war is inevitable, the use of air power is seen as the preferable means of conducting operations instead of financially burdensome land battles which are more likely to cause heavy loss of life. The use of Air Power has gained importance in NATO operations in the Post-Cold War era. For example, air power has undertaken a decisive role from the beginning to the end of the operation in Libya. From this point of view, the most important issue to consider is how to direct air power more effectively at operational level. NATO's Core JFAC (Joint Force Air Command) was established in 2012 to control joint air power at operational level from a single center. US had experienced JFAC aproach in the Operation Desert Storm in 1991. UK, France, Germany, Italy and Spain are also directing their air power from their JFAC structures. Joint air power can be directed from a single center at operational level by means of JFAC. JFAC aproach provides complex planning progress of Air Power to be controled faster in a single center. An Air Power with a large number of aircrafts, long range missiles of cutting-edge technology may have difficulties in achieving results unless directed effectively. In this article, directing air power more effectively at operational level has been studied in the framework of directing air power from a single center carried out by SWOT analysis technique. "Directing Air Power at operational level from a single center similar to JFAC-like structure" is compared with "Directing Air Power at operational level from two centers similar to AC (Air Command) + CAOC (Combined Air Operations Center) structure" As a result of this study, it is assessed that directing air power at operational level from a single center would bring effectiveness to the air campaign. The study examines directing air power at operational level. Developments at political, strategic and tactical levels have been ignored.

Machine & electrical double control air dryer for vehicle air braking system

NASA Astrophysics Data System (ADS)

Zhang, Xuan; Yang, Liu; Wang, Xian Yan; Tan, Xiao Yan; Wang, Wei

2017-09-01

As is known to all, a vehicle air brake system, in which usually contains moisture. To solve the problem, it is common to use air dryer to dry compressed air effectively and completely remove the moisture and oil of braking system. However, the existing air dryer is not suitable for all commercial vehicles. According to the operational status of the new energy vehicles in the initial operating period, the structure design principle of the machine & electric control air dryer is expounded from the aspects of the structure and operating principle, research & development process.

Effect of increased groundwater viscosity on the remedial performance of surfactant-enhanced air sparging

NASA Astrophysics Data System (ADS)

Choi, Jae-Kyeong; Kim, Heonki; Kwon, Hobin; Annable, Michael D.

2018-03-01

The effect of groundwater viscosity control on the performance of surfactant-enhanced air sparging (SEAS) was investigated using 1- and 2-dimensional (1-D and 2-D) bench-scale physical models. The viscosity of groundwater was controlled by a thickener, sodium carboxymethylcellulose (SCMC), while an anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), was used to control the surface tension of groundwater. When resident DI water was displaced with a SCMC solution (500 mg/L), a SDBS solution (200 mg/L), and a solution with both SCMC (500 mg/L) and SDBS (200 mg/L), the air saturation for sand-packed columns achieved by air sparging increased by 9.5%, 128%, and 154%, respectively, (compared to that of the DI water-saturated column). When the resident water contained SCMC, the minimum air pressure necessary for air sparging processes increased, which is considered to be responsible for the increased air saturation. The extent of the sparging influence zone achieved during the air sparging process using the 2-D model was also affected by viscosity control. Larger sparging influence zones (de-saturated zone due to air injection) were observed for the air sparging processes using the 2-D model initially saturated with high-viscosity solutions, than those without a thickener in the aqueous solution. The enhanced air saturations using SCMC for the 1-D air sparging experiment improved the degradative performance of gaseous oxidation agent (ozone) during air sparging, as measured by the disappearance of fluorescence (fluorescein sodium salt). Based on the experimental evidence generated in this study, the addition of a thickener in the aqueous solution prior to air sparging increased the degree of air saturation and the sparging influence zone, and enhanced the remedial potential of SEAS for contaminated aquifers.

Clean Air Technology Center

EPA Pesticide Factsheets

The Clean Air Technology Center provides resources for emerging and existing air pollution prevention and control technologies and provides public access to data and information on their use, effectiveness and cost.

The Effect of Shared Information on Pilot/Controller Situation Awareness and Re-Route Negotiation

NASA Technical Reports Server (NTRS)

Farley, Todd C.; Hansman, R. John; Endsley, Mica R.; Amonlirdviman, Keith; Vigeant-Langlois, Laurence

1998-01-01

The effect of shared information is assessed in terms of pilot/controller negotiation and shared situation awareness. Pilot goals and situation awareness requirements are developed and compared against those of air traffic controllers to identify areas of common and competing interest. A part-task simulator experiment is described which probes pilot/controller interaction in areas where common information has the potential to lead to contention, as identified in the comparative analysis. Preliminary results are presented which suggest that shared information can effect more collaborative interaction between pilots and air traffic controllers.

Effect of air humidification on the sick building syndrome and perceived indoor air quality in hospitals: a four month longitudinal study.

PubMed Central

Nordström, K; Norbäck, D; Akselsson, R

1994-01-01

The sensation of dryness and irritation is essential in the sick building syndrome (SBS), and such symptoms are common in both office and hospital employees. In Scandinavia, the indoor relative humidity in well ventilated buildings is usually in the range 10-35% in winter. The aim of this study was to evaluate the effect of steam air humidification on SBS and perceived air quality during the heating season. The study base consisted of a dynamic population of 104 hospital employees, working in four new and well ventilated geriatric hospital units in southern Sweden. Air humidification raised the relative air humidity to 40-45% in two units during a four months period, whereas the other two units served as controls with relative humidity from 25-35%. Symptoms and perceived indoor air quality were measured before and after the study period by a standardised self administered questionnaire. The technical measurements comprised room temperature, air humidity, static electricity, exhaust air flow, aerosols, microorganisms, and volatile organic compounds in the air. The most pronounced effect of the humidification was a significant decrease of the sensation of air dryness, static electricity, and airway symptoms. After four months of air humidification during the heating season, 24% reported a weekly sensation of dryness in humidified units, compared with 73% in controls. No significant changes in symptoms of SBS or perceived air quality over time were found in the control group. The room temperature in all units was between 21-23 degrees C, and no significant effect of air humidification on the air concentration of aerosols or volatile organic compounds was found. No growth of microorganisms was found in the supply air ducts, and no legionella bacteria were found in the supply water of the humidifier. Air humidification, however, significantly reduced the measured personal exposure to static electricity. It is concluded that air humidification during the heating season in colder climates can decrease symptoms of SBS and perception of dry air. PMID:8000493

Quantifying the effect of air quality control measures during the 2010 Commonwealth Games at Delhi, India

NASA Astrophysics Data System (ADS)

Beig, Gufran; Chate, Dilip M.; Ghude, Sachin. D.; Mahajan, A. S.; Srinivas, R.; Ali, K.; Sahu, S. K.; Parkhi, N.; Surendran, D.; Trimbake, H. R.

2013-12-01

In 2010, the XIX Commonwealth Games (CWG-2010) were held in India for the first time at Delhi and involved 71 commonwealth nations and dependencies with more than 6000 athletes participating in 272 events. This was the largest international multi-sport event to be staged in India and strict emission controls were imposed during the games in order to ensure improved air quality for the participating athletes as a significant portion of the population in Delhi is regularly exposed to elevated levels of pollution. The air quality control measures ranged from vehicular and traffic controls to relocation of factories and reduction of power plant emissions. In order to understand the effects of these policy induced control measures, a network of air quality and weather monitoring stations was set-up across different areas in Delhi under the Government of India's System of Air quality Forecasting And Research (SAFAR) project. Simultaneous measurements of aerosols, reactive trace gases (e.g. NOx, O3, CO) and meteorological parameters were made before, during and after CWG-2010. Contrary to expectations, the emission controls implemented were not sufficient to reduce the pollutants, instead in some cases, causing an increase. The measured pollutants regularly exceeded the National Ambient Air Quality limits over the games period. The reasons for this increase are attributed to an underestimation of the required control measures, which resulted in inadequate planning. The results indicate that any future air quality control measures need to be well planned and strictly imposed in order to improve the air quality in Delhi, which affects a large population and is deteriorating rapidly. Thus, the presence of systematic high resolution data and realistic emission inventories through networks such as SAFAR will be directly useful for the future.

An Integrated WRF-CAMx Modeling Approach for Impact Analysis of Implementing the Emergency PM2.5 Control Measures during Red Alerts in Beijing in December 2015

NASA Astrophysics Data System (ADS)

Jia, J.; Cheng, S.; Lei, L.; Lang, J.

2017-12-01

In December 2015, the Beijing-Tianjin-Hebei (BTH) region experienced several episodes of heavy air pollution. Beijing municipal government therefore issued 2 red alerts on December 7 and 19, respectively, and also implemented emergency control measures to alleviate the negative effects of pollution. It is estimated that the heavy pollutions in 2 red alert periods in Beijing were due mainly to the accumulation of air pollutants from local emission sources and the transboundary transport of pollutants from surrounding areas. The collected meteorological and PM2.5 data indicate that the severity of air pollutions were enlarged by the poor meteorological conditions along with lower mixing layer height. In this study, the WRF-CAMx modeling system was utilized not only for analyzing the contributions of PM2.5 from different sources, but also for quantitatively assessing the effects of implementing various emergency control measures on PM2.5 pollution control during the red alert periods. The modeling results show that local emissions were the most dominant contributors (64.8%-83.5%) among all emission sources, while the main external contributions came from the city of Baoding (3.4%-9.3%). In addition, among 5 different emission source categories, coal and traffic were the two dominant contributors to PM2.5 concentration in urban area of Beijing. Then four pollution control scenarios were designed particularly to investigate the effectiveness of the emergency control measures, and the results show that, generally these emergency control measures have positive effects on air pollution reduction. In particular, restrictive measures of traffic volume control and industrial activity shutdown/suspension have been found as the most effective measures in comparison to other emergency control measures. It is recommended that such effective measures should be considered to implement when next time similar heavy air pollutions occur in the city of Beijing.

Clean Air Technology Center Products

EPA Pesticide Factsheets

The Clean Air Technology Center provides resources for emerging and existing air pollution prevention and control technologies and provides public access to data and information on their use, effectiveness and cost.

Multi-stage versus single-stage inflation and deflation cycle for alternating low pressure air mattresses to prevent pressure ulcers in hospitalised patients: a randomised-controlled clinical trial.

PubMed

Demarré, L; Beeckman, D; Vanderwee, K; Defloor, T; Grypdonck, M; Verhaeghe, S

2012-04-01

The duration and the amount of pressure and shear must be reduced in order to minimize the risk of pressure ulcer development. Alternating low pressure air mattresses with multi-stage inflation and deflation cycle of the air cells have been developed to relieve pressure by sequentially inflating and deflating the air cells. Evidence about the effectiveness of this type of mattress in clinical practice is lacking. This study aimed to compare the effectiveness of an alternating low pressure air mattress that has a standard single-stage inflation and deflation cycle of the air cells with an alternating low pressure air mattress with multi-stage inflation and deflation cycle of the air cells. A randomised controlled trial was performed in a convenience sample of 25 wards in five hospitals in Belgium. In total, 610 patients were included and randomly assigned to the experimental group (n=298) or the control group (n=312). In the experimental group, patients were allocated to an alternating low pressure air mattress with multi-stage inflation and deflation cycle of the air cells. In the control group, patients were allocated to an alternating low pressure air mattress with a standard single-stage inflation and deflation cycle of the air cells. The outcome was defined as cumulative pressure ulcer incidence (Grade II-IV). An intention-to-treat analysis was performed. There was no significant difference in cumulative pressure ulcer incidence (Grade II-IV) between both groups (Exp.=5.7%, Contr.=5.8%, p=0.97). When patients developed a pressure ulcer, the median time was 5.0 days in the experimental group (IQR=3.0-8.5) and 8.0 days in the control group (IQR=3.0-8.5) (Mann-Whitney U-test=113, p=0.182). The probability to remain pressure ulcer free during the observation period in this trial did not differ significantly between the experimental group and the control group (log-rank χ(2)=0.013, df=1, p=0.911). An alternating low pressure air mattress with multi-stage inflation and deflation of the air cells does not result in a significantly lower pressure ulcer incidence compared to an alternating low pressure air mattress with a standard single-stage inflation and deflation cycle of the air cells. Both alternating mattress types are equally effective to prevent pressure ulcer development. © 2011 Elsevier Ltd. All rights reserved.

Assessment of Co-benefits of vehicle emission reduction measures for 2015-2020 in the Pearl River Delta region, China.

PubMed

Liu, Yong-Hong; Liao, Wen-Yuan; Lin, Xiao-Fang; Li, Li; Zeng, Xue-Lan

2017-04-01

Vehicle emissions have become one of the key factors affecting the urban air quality and climate change in the Pearl River Delta (PRD) region, so it is important to design policies of emission reduction based on quantitative Co-benefits for air pollutants and greenhouse gas (GHG). Emissions of air pollutants and GHG by 2020 was predicted firstly based on the no-control scenario, and five vehicle emissions reduction scenarios were designed in view of the economy, technology and policy, whose emissions reduction were calculated. Then Co-benefits between air pollutants and GHG were quantitatively analyzed by the methods of coordinate system and cross-elasticity. Results show that the emissions reduction effects and the Co-benefits of different measures vary greatly in 2015-2020. If no control scheme was applied, most air pollutants and GHG would increase substantially by 20-64% by 2020, with the exception of CO, VOC and PM 2.5 . Different control measures had different reduction effects for single air pollutant and GHG. The worst reduction measure was Eliminating Motorcycles with average reducing rate 0.09% for air pollutants and GHG, while the rate from Updated Emission Standard was 41.74%. Eliminating Yellow-label Vehicle scenario had an obvious reduction effect for every single pollutant in the earlier years, but Co-benefits would descent to zero in later by 2020. From the perspective of emission reductions and co-control effect, Updated Emission Standard scenario was best for reducing air pollutants and GHG substantially (tanα=1.43 and Els=1.77). Copyright © 2016 Elsevier Ltd. All rights reserved.

Implications of alternative assumptions regarding future air pollution control in RCP-like scenarios

NASA Astrophysics Data System (ADS)

Chuwah, Clifford; van Noije, Twan; van Vuuren, Detlef; Hazeleger, Wilco; Strunk, Achim; Deetman, Sebastiaan; Mendoza Beltran, Angelica; van Vliet, Jasper

2013-04-01

Estimation of future emissions of short-lived trace gases and aerosols from human activities is a main source of uncertainty in projections of future air quality and climate forcing. The Representative Concentration Pathways (RCPs), however, all assume that worldwide ambitious air pollution control policies will be implemented in the coming decades. In this study, we therefore explore the consequences of four alternative emission scenarios generated using the IMAGE integrated assessment model following the methods used to generate the RCPs. These scenarios combine low and high air pollution variants of the scenarios with radiative forcing targets in 2100 of 2.6 W/m2 and 6.0 W/m2 (the high air pollution variants assume no improvement in emission factors, representing a hypothetical upper end of emission levels). Analysis using the global atmospheric chemistry and transport model TM5 shows that climate mitigation and air pollution control policy variants studied here have similar large-scale effects on the concentrations of ozone and black carbon; the impact of climate policy, however, has a stronger impact on sulphate concentrations. Air pollution control measures could significantly reduce the warming by tropospheric ozone and black carbon and the cooling by sulphate already in 2020, and on the longer term contribute to enhanced warming by methane. These effects tend to cancel each other at the global scale. According to our estimates the effect of the worldwide implementation of air pollution control measures on the total global mean direct radiative forcing in 2050 is +0.09 W/m2 in the 6.0 W/m2 scenario and -0.16 W/m2 in the 2.6 W/m2 scenario.

About the Clean Air Technology Center

EPA Pesticide Factsheets

The Clean Air Technology Center provides resources for emerging and existing air pollution prevention and control technologies and provides public access to data and information on their use, effectiveness and cost.

The role of meteorological conditions and pollution control strategies in reducing air pollution in Beijing during APEC 2014 and Victory Parade 2015

NASA Astrophysics Data System (ADS)

Liang, Pengfei; Zhu, Tong; Fang, Yanhua; Li, Yingruo; Han, Yiqun; Wu, Yusheng; Hu, Min; Wang, Junxia

2017-11-01

To control severe air pollution in China, comprehensive pollution control strategies have been implemented throughout the country in recent years. To evaluate the effectiveness of these strategies, the influence of meteorological conditions on levels of air pollution needs to be determined. Using the intensive air pollution control strategies implemented during the Asia-Pacific Economic Cooperation Forum in 2014 (APEC 2014) and the 2015 China Victory Day Parade (Victory Parade 2015) as examples, we estimated the role of meteorological conditions and pollution control strategies in reducing air pollution levels in Beijing. Atmospheric particulate matter of aerodynamic diameter ≤ 2.5 µm (PM2.5) samples were collected and gaseous pollutants (SO2, NO, NOx, and O3) were measured online at a site in Peking University (PKU). To determine the influence of meteorological conditions on the levels of air pollution, we first compared the air pollutant concentrations during days with stable meteorological conditions. However, there were few days with stable meteorological conditions during the Victory Parade. As such, we were unable to estimate the level of emission reduction efforts during this period. Finally, a generalized linear regression model (GLM) based only on meteorological parameters was built to predict air pollutant concentrations, which could explain more than 70 % of the variation in air pollutant concentration levels, after incorporating the nonlinear relationships between certain meteorological parameters and the concentrations of air pollutants. Evaluation of the GLM performance revealed that the GLM, even based only on meteorological parameters, could be satisfactory to estimate the contribution of meteorological conditions in reducing air pollution and, hence, the contribution of control strategies in reducing air pollution. Using the GLM, we found that the meteorological conditions and pollution control strategies contributed 30 and 28 % to the reduction of the PM2.5 concentration during APEC and 38 and 25 % during the Victory Parade, respectively, based on the assumption that the concentrations of air pollutants are only determined by meteorological conditions and emission intensities. We also estimated the contribution of meteorological conditions and control strategies in reducing the concentrations of gaseous pollutants and PM2.5 components with the GLMs, revealing the effective control of anthropogenic emissions.

Impact of air pollution control costs on the cost and spatial arrangement of cellulosic biofuel production in the U.S.

PubMed

Murphy, Colin W; Parker, Nathan C

2014-02-18

Air pollution emissions regulation can affect the location, size, and technology choice of potential biofuel production facilities. Difficulty in obtaining air pollutant emission permits and the cost of air pollution control devices have been cited by some fuel producers as barriers to development. This paper expands on the Geospatial Bioenergy Systems Model (GBSM) to evaluate the effect of air pollution control costs on the availability, cost, and distribution of U.S. biofuel production by subjecting potential facility locations within U.S. Clean Air Act nonattainment areas, which exceed thresholds for healthy air quality, to additional costs. This paper compares three scenarios: one with air quality costs included, one without air quality costs, and one in which conversion facilities were prohibited in Clean Air Act nonattainment areas. While air quality regulation may substantially affect local decisions regarding siting or technology choices, their effect on the system as a whole is small. Most biofuel facilities are expected to be sited near to feedstock supplies, which are seldom in nonattainment areas. The average cost per unit of produced energy is less than 1% higher in the scenarios with air quality compliance costs than in scenarios without such costs. When facility construction is prohibited in nonattainment areas, the costs increase by slightly over 1%, due to increases in the distance feedstock is transported to facilities in attainment areas.

[Does ultraclean air in the operating room provide greater safety?].

PubMed

van Tiel, Frank H; Buiting, Anton G; Meessen, Nico E L; Voss, Andreas; Vos, Margreet C

2010-01-01

The Dutch quality control plan for climatisation of the operating room (OR), which was published in 2005, describes the management and maintenance of the air conditioning system. This management plan proposes a standard for air quality in class 1 ORs. This has been adopted by the Dutch Orthopaedic Society, but not by other surgical societies. The British study which underlies the proposed norm for air quality in class 1 ORs, a study on the infection preventive effect of ultraclean air, dates from 1982 and is inadequately controlled for prophylactic use of antibiotics. Antibiotic prophylaxis in itself already reduces the number of surgical site infections.-More recent studies fail to show an infection preventive effect of ultraclean air in the OR. The Dutch Working Party for Infection Prevention (WIP) ought to take the initiative, together with the medical Scientific Societies and the Society of Infection Prevention and Control in the health care setting (VHIG), to establish enforceable norms for microbiological air quality and to set criteria as to which types of operations are allowed to be performed in which class of OR.

EFFECT OF AIR-POLLUTION CONTROL ON DEATH RATES IN DUBLIN, IRELAND: AN INTERVENTION STUDY. (R827353C006)

EPA Science Inventory

Background Particulate air pollution episodes have been associated with increased daily death. However, there is little direct evidence that diminished particulate air pollution concentrations would lead to reductions in death rates. We assessed the effect of ...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 1 Device categories Characteristics adversely affected Fuel-Air System Carburetors and fuel injection systems All. Air-fuel ratio modifiers (e.g., air bleeds) All. Atomization devices (acoustic and mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 1 Device categories Characteristics adversely affected Fuel-Air System Carburetors and fuel injection systems All. Air-fuel ratio modifiers (e.g., air bleeds) All. Atomization devices (acoustic and mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

Study on the stability of waterpower-speed control system for hydropower station with air cushion surge chamber

NASA Astrophysics Data System (ADS)

Guo, W. C.; Yang, J. D.; Chen, J. P.; Teng, Y.

2014-03-01

According to the fact that the effects of penstock, unit and governor on stability of water level fluctuation for hydropower station with air cushion surge chamber are neglected in previous researches, in this paper, Thoma assumption is broken through, the complete mathematical model of waterpower-speed control system for hydropower station with air cushion surge chamber is established, and the comprehensive transfer function and linear homogeneous differential equation that characterize the dynamic characteristics of system are derived. The stability domain that characterizes the good or bad of stability quantitatively is drawn by using the stability conditions. The effects of the fluid inertia in water diversion system, the air cushion surge chamber parameters, hydraulic turbine characteristics, generator characteristics, and regulation modes of governor on the stability of waterpower-speed control system are analyzed through stability domain. The main conclusions are as follows: The fluid inertia in water diversion system and hydraulic turbine characteristics have unfavorable effects on the system while generator characteristics have favorable effect. The stability keeps getting better with the increase of chamber height and basal area and the decrease of air pressure and air polytropic exponent. The stability of power regulation mode is obviously better than that of frequency regulation mode.

Air Traffic Control: Weak Computer Security Practices Jeopardize Flight Safety

DOT National Transportation Integrated Search

1998-05-01

Given the paramount importance of computer security of Air Traffic Control (ATC) systems, Congress asked the General Accounting Office to determine (1) whether the Fedcral Aviation Administration (FAA) is effectively managing physical security at ATC...

Surveying air traffic control specialist perception of scheduling regulations

NASA Astrophysics Data System (ADS)

Thompson, Darrius E.

While there have been several studies conducted on air traffic controller fatigue, there is a lack of research on the subject since the scheduling policy changes that took place in 2012. The effectiveness of these changes has yet to be measured. The goal of this study was to investigate air traffic control specialist views towards the number of hours scheduled between shifts, changes in perception since 2012 regulation changes, and external factors that impact fatigue. A total of 54 FAA air traffic control specialist completed an online questionnaire. The results from the survey showed that the majority of respondents felt the 2012 regulation changes were not sufficient to address fatigue issues, and work with some amount sleep deprivation. The factors that appeared to have the most significant effect on fatigue included facility level, age group, availability of recuperative breaks, and children under 18 in the home.

Air Pollution. Part A: Analysis.

ERIC Educational Resources Information Center

Ledbetter, Joe O.

Two facets of the engineering control of air pollution (the analysis of possible problems and the application of effective controls) are covered in this two-volume text. Part A covers Analysis, and Part B, Prevention and Control. (This review is concerned with Part A only.) This volume deals with the terminology, methodology, and symptomatology…

Influence of Air Humidity and Water Particles on Dust Control Using Ultrasonic Atomization

NASA Astrophysics Data System (ADS)

Okawa, Hirokazu; Nishi, Kentaro; Shindo, Dai; Kawamura, Youhei

2012-07-01

The influence of air humidity and water particles on dust control was examined using ultrasonic atomization at 2.4 MHz, an acrylic box (61 L), and four types of ore dust samples: green tuff (4 µm), green tuff (6 µm), kaolin, and silica. It was clearly demonstrated that ultrasonic atomization was effective in raising humidity rapidly. However, at high relative air humidity, the water particles remained stable in the box without changing to water vapor. Ultrasonic atomization was applied to suppress dust dispersion and 40-95% dust reduction was achieved at 83% relative air humidity. Dust dispersion was more effective with ultrasonic atomization than without.

Critical loads as a policy tool for protecting ecosystems from the effects of air pollutants

Treesearch

Douglas A. Burns; Tamara Blett; Richard Haeuber; Linda H. Pardo

2008-01-01

Framing the effects of air pollutants on ecosystems in terms of a "critical load" provides a meaningful approach for research scientists to communicate policy-relevant science to air-quality policy makers and natural resource managers. A critical-loads approach has been widely used to shape air-pollutant control policy in Europe since the 1980s, yet has only...

The effectiveness of air bags.

PubMed

Barry, S; Ginpil, S; O'Neill, T J

1999-11-01

Previous research has shown that the installation of air bags in vehicles significantly reduces crash related deaths, but these analyses have used statistical techniques which have not been capable of controlling for other major determinants of crash survival. This study analysed data from the US FARS database of fatal crashes using conditional logistic regression which is simultaneously able to estimate occupant protection effects for a range of variables. Results of the analysis provided a comparative quantification of both the effect of the air bag as well as other well known determinants of occupant crash survival (age, seat belt use, and gender). When potentially confounding variables were controlled, both the driver and passenger side air bag devices were shown to significantly reduce the probability of death in direct frontal collisions, but the effect size calculated was small compared to the effect of the seat belt. The effect size may also be very small in absolute terms depending on the severity of the crash involved. Given the limited benefit of the air bag, efforts to promote air bags seem particularly difficult to justify in countries such as the United States where the vastly superior occupant protection of the seat belt is under-utilised.

Air gun wounding and current UK laws controlling air weapons.

PubMed

Bruce-Chwatt, Robert Michael

2010-04-01

Air weapons whether rifles or pistols are, potentially, lethal weapons. The UK legislation is complex and yet little known to the public. Hunting with air weapons and the laws controlling those animals that are permitted to be shot with air weapons is even more labyrinthine due to the legal power limitations on the possession of air weapons. Still relatively freely available by mail order or on the Internet, an increasing number of deaths have been reported from the misuse of air weapons or accidental discharges. Ammunition for air weapons has become increasingly sophisticated, effective and therefore increasingly dangerous if misused, though freely available being a mere projectile without a concomitant cartridge containing a propellant and an initiator.

A case study of the relative effects of power plant nitrogen oxides and sulfur dioxide emission reductions on atmospheric nitrogen deposition.

PubMed

Vijayaraghavan, Krish; Seigneur, Christian; Bronson, Rochelle; Chen, Shu-Yun; Karamchandani, Prakash; Walters, Justin T; Jansen, John J; Brandmeyer, Jo Ellen; Knipping, Eladio M

2010-03-01

The contrasting effects of point source nitrogen oxides (NOx) and sulfur dioxide (SO2) air emission reductions on regional atmospheric nitrogen deposition are analyzed for the case study of a coal-fired power plant in the southeastern United States. The effect of potential emission reductions at the plant on nitrogen deposition to Escambia Bay and its watershed on the Florida-Alabama border is simulated using the three-dimensional Eulerian Community Multiscale Air Quality (CMAQ) model. A method to quantify the relative and individual effects of NOx versus SO2 controls on nitrogen deposition using air quality modeling results obtained from the simultaneous application of NOx and SO2 emission controls is presented and discussed using the results from CMAQ simulations conducted with NOx-only and SO2-only emission reductions; the method applies only to cases in which ambient inorganic nitrate is present mostly in the gas phase; that is, in the form of gaseous nitric acid (HNO3). In such instances, the individual effects of NOx and SO2 controls on nitrogen deposition can be approximated by the effects of combined NOx + SO2 controls on the deposition of NOy, (the sum of oxidized nitrogen species) and reduced nitrogen species (NHx), respectively. The benefit of controls at the plant in terms of the decrease in nitrogen deposition to Escambia Bay and watershed is less than 6% of the overall benefit due to regional Clean Air Interstate Rule (CAIR) controls.

Interactive short-term effects of equivalent temperature and air pollution on human mortality in Berlin and Lisbon.

PubMed

Burkart, Katrin; Canário, Paulo; Breitner, Susanne; Schneider, Alexandra; Scherber, Katharina; Andrade, Henrique; Alcoforado, Maria João; Endlicher, Wilfried

2013-12-01

There is substantial evidence that both temperature and air pollution are predictors of mortality. Thus far, few studies have focused on the potential interactive effects between the thermal environment and different measures of air pollution. Such interactions, however, are biologically plausible, as (extreme) temperature or increased air pollution might make individuals more susceptible to the effects of each respective predictor. This study investigated the interactive effects between equivalent temperature and air pollution (ozone and particulate matter) in Berlin (Germany) and Lisbon (Portugal) using different types of Poisson regression models. The findings suggest that interactive effects exist between air pollutants and equivalent temperature. Bivariate response surface models and generalised additive models (GAMs) including interaction terms showed an increased risk of mortality during periods of elevated equivalent temperatures and air pollution. Cold effects were mostly unaffected by air pollution. The study underscores the importance of air pollution control in mitigating heat effects. Copyright © 2013 Elsevier Ltd. All rights reserved.

Design of an air traffic computer simulation system to support investigation of civil tiltrotor aircraft operations

NASA Technical Reports Server (NTRS)

Rogers, Ralph V.

1992-01-01

This research project addresses the need to provide an efficient and safe mechanism to investigate the effects and requirements of the tiltrotor aircraft's commercial operations on air transportation infrastructures, particularly air traffic control. The mechanism of choice is computer simulation. Unfortunately, the fundamental paradigms of the current air traffic control simulation models do not directly support the broad range of operational options and environments necessary to study tiltrotor operations. Modification of current air traffic simulation models to meet these requirements does not appear viable given the range and complexity of issues needing resolution. As a result, the investigation of systemic, infrastructure issues surrounding the effects of tiltrotor commercial operations requires new approaches to simulation modeling. These models should be based on perspectives and ideas closer to those associated with tiltrotor air traffic operations.

Pronunciation and Comprehension in English as a Lingua Franca Communication: Effect of L1 Influence in International Aviation Communication

ERIC Educational Resources Information Center

Kim, Hyejeong; Billington, Rosey

2018-01-01

This article explores the issues of pronunciation and comprehension in the English as a lingua franca (ELF) context of pilot--air traffic controller radiotelephony communication, and how these are handled in the proficiency rating scale globally used to assess pilots and air traffic controllers engaging in international flight and air traffic…

Airborne asphyxia: an international problem

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

Friedlander, G.D.

1965-10-01

An overview is presented of air pollution which has become a real problem that affects virtually every major industrial city in the United States and Europe. Air pollution presents one of the most serious threats to the coal industry which produces about 55% of the electric power in the USA. There are meteorological and climatological factors that influence the action of air borne pollutants. The effects of SO/sub 2/ and N/sub 2/O on human health are discussed. Methods of reducing SO/sub 2/ emissions are presented. The results of studies by TVA in SO/sub 2/ monitoring and control have been appliedmore » in planning subsequent plants. There are an estimated 88 million motor vehicles on the nation's highways that contribute to air pollution. Control devices for cars can effectively reduce the amount of air contaminants released from motor vehicle exhausts. From numerous surveys, it is obvious that the sources of air pollution are numerous and complex. Total and effective remedial action must be undertaken to correct the situation.« less

“Air pollution in Delhi: Its Magnitude and Effects on Health”

PubMed Central

Rizwan, SA; Nongkynrih, Baridalyne; Gupta, Sanjeev Kumar

2013-01-01

Air pollution is responsible for many health problems in the urban areas. Of late, the air pollution status in Delhi has undergone many changes in terms of the levels of pollutants and the control measures taken to reduce them. This paper provides an evidence-based insight into the status of air pollution in Delhi and its effects on health and control measures instituted. The urban air database released by the World Health Organization in September 2011 reported that Delhi has exceeded the maximum PM10 limit by almost 10-times at 198 μg/m3. Vehicular emissions and industrial activities were found to be associated with indoor as well as outdoor air pollution in Delhi. Studies on air pollution and mortality from Delhi found that all-natural-cause mortality and morbidity increased with increased air pollution. Delhi has taken several steps to reduce the level of air pollution in the city during the last 10 years. However, more still needs to be done to further reduce the levels of air pollution. PMID:23559696

Managing Air Quality - Program Implementation

EPA Pesticide Factsheets

Describes elements for the set of activities to ensure that control strategies are put into effect and that air quality goals and standards are fulfilled, permitting programs, and additional resources related to implementation under the Clean Air Act.

Guidelines for Controlling Indoor Air Quality Problems Associated with Kilns, Copiers, and Welding in Schools. Technical Bulletin.

ERIC Educational Resources Information Center

Turner, Ronald W.; And Others

Guidelines for controlling indoor air quality problems associated with kilns, copiers, and welding in schools are provided in this document. Individual sections on kilns, duplicating equipment, and welding operations contain information on the following: sources of contaminants; health effects; methods of control; ventilation strategies; and…

The U.S. Air Force Academy Lacked Effective Controls Over Heritage Assets and Guest House Inventories, and Inappropriately Solicited and Accepted Monetary Gifts

DTIC Science & Technology

2013-09-23

during that time frame. Finding B 10 │ DODIG-2013-138 Finding B USAFA Heritage Program Lacked Adequate Controls USAFA officials did not have effective ...E M B E R 2 3 , 2 0 1 3 Report No. DODIG-2013-138 The U.S. Air Force Academy Lacked Effective Controls Over Heritage Assets and Guest House...for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data

Multi-load Groups Coordinated Load Control Strategy Considering Power Network Constraints

NASA Astrophysics Data System (ADS)

Liu, Meng; Zhao, Binchao; Wang, Jun; Zhang, Guohui; Wang, Xin

2017-05-01

Loads with energy storage property can actively participate in power balance for power systems, this paper takes air conditioner as a controllable load example, proposing a multi-load groups coordinated load control strategy considering power network constraints. Firstly, two load control modes considering recovery of load diversity are designed, blocking power oscillation of aggregated air conditioners. As the same time, air conditioner temperature setpoint recovery control strategy is presented to avoid power recovery peak. Considering inherent characteristics of two load control modes, an coordinated load control mode is designed by combining the both. Basing on this, a multi-load groups coordinated load control strategy is proposed. During the implementing of load control, power network constraints should be satisfied. An indice which can reflect the security of power system operating is defined. By minimizing its value through optimization, the change of air conditioning loads’ aggregated power on each load bus can be calculated. Simulations are conducted on an air conditioners group and New England 10-generator 39-bus system, verifying the effectiveness of the proposed multi-load groups coordinated load control strategy considering power network constraints.

Patient warming excess heat: the effects on orthopedic operating room ventilation performance.

PubMed

Belani, Kumar G; Albrecht, Mark; McGovern, Paul D; Reed, Mike; Nachtsheim, Christopher

2013-08-01

Patient warming has become a standard of care for the prevention of unintentional hypothermia based on benefits established in general surgery. However, these benefits may not fully translate to contamination-sensitive surgery (i.e., implants), because patient warming devices release excess heat that may disrupt the intended ceiling-to-floor ventilation airflows and expose the surgical site to added contamination. Therefore, we studied the effects of 2 popular patient warming technologies, forced air and conductive fabric, versus control conditions on ventilation performance in an orthopedic operating room with a mannequin draped for total knee replacement. Ventilation performance was assessed by releasing neutrally buoyant detergent bubbles ("bubbles") into the nonsterile region under the head-side of the anesthesia drape. We then tracked whether the excess heat from upper body patient warming mobilized the "bubbles" into the surgical site. Formally, a randomized replicated design assessed the effect of device (forced air, conductive fabric, control) and anesthesia drape height (low-drape, high-drape) on the number of bubbles photographed over the surgical site. The direct mass-flow exhaust from forced air warming generated hot air convection currents that mobilized bubbles over the anesthesia drape and into the surgical site, resulting in a significant increase in bubble counts for the factor of patient warming device (P < 0.001). Forced air had an average count of 132.5 versus 0.48 for conductive fabric (P = 0.003) and 0.01 for control conditions (P = 0.008) across both drape heights. Differences in average bubble counts across both drape heights were insignificant between conductive fabric and control conditions (P = 0.87). The factor of drape height had no significant effect (P = 0.94) on bubble counts. Excess heat from forced air warming resulted in the disruption of ventilation airflows over the surgical site, whereas conductive patient warming devices had no noticeable effect on ventilation airflows. These findings warrant future research into the effects of forced air warming excess heat on clinical outcomes during contamination-sensitive surgery.

School Environmental Intervention to Reduce Particulate Pollutant Exposures for Children with Asthma

PubMed Central

Jhun, Iny; Gaffin, Jonathan M.; Coull, Brent A.; Huffaker, Michelle F.; Petty, Carter R.; Sheehan, William J.; Baxi, Sachin N.; Lai, Peggy S.; Kang, Choong-Min; Wolfson, Jack M.; Gold, Diane R.; Koutrakis, Petros; Phipatanakul, Wanda

2016-01-01

Background Home-based interventions to improve indoor air quality have demonstrated benefits for asthma morbidity, yet little is known about the effect of environmental interventions in the school setting. Objective We piloted the feasibility and effectiveness of a classroom-based air cleaner intervention to reduce particulate pollutants in classrooms of children with asthma. Methods In this pilot randomized controlled trial, we assessed the effect of air cleaners on indoor air particulate pollutant concentrations in 18 classrooms (9 control, 9 intervention) in 3 urban elementary schools. We enrolled 25 asthmatic children (13 control, 12 intervention) aged 6–10 years old. Classroom air pollutant measurements and spirometry were completed once prior to and twice after randomization. Asthma symptoms were surveyed every 3 months. Results Baseline classroom levels of fine particulate matter (PM2.5) and black carbon (BC) were 6.3 μg/m3 and 0.41 μg/m3, respectively. When comparing the intervention to the control group, classroom PM2.5 levels were reduced by 49% and 42%, and BC levels were reduced by 58% and 55% in the first and second follow-up periods, respectively (p < 0.05 for all comparisons). When comparing the children randomized to intervention and control classrooms, there was a modest improvement in peak flow, but no significant changes in forced expiratory volume in 1 second (FEV1) and asthma symptoms. Conclusion In this pilot study, a classroom-based air cleaner intervention led to significant reductions in PM2.5 and BC. Future large-scale studies should comprehensively evaluate the effect of school-based environmental interventions on pediatric asthma morbidity. PMID:27641483

School Environmental Intervention to Reduce Particulate Pollutant Exposures for Children with Asthma.

PubMed

Jhun, Iny; Gaffin, Jonathan M; Coull, Brent A; Huffaker, Michelle F; Petty, Carter R; Sheehan, William J; Baxi, Sachin N; Lai, Peggy S; Kang, Choong-Min; Wolfson, Jack M; Gold, Diane R; Koutrakis, Petros; Phipatanakul, Wanda

Home-based interventions to improve indoor air quality have demonstrated benefits for asthma morbidity, yet little is known about the effect of environmental interventions in the school setting. We piloted the feasibility and effectiveness of a classroom-based air cleaner intervention to reduce particulate pollutants in classrooms of children with asthma. In this pilot randomized controlled trial, we assessed the effect of air cleaners on indoor air particulate pollutant concentrations in 18 classrooms (9 control, 9 intervention) in 3 urban elementary schools. We enrolled 25 children with asthma (13 control, 12 intervention) aged 6 to 10 years. Classroom air pollutant measurements and spirometry were completed once before and twice after randomization. Asthma symptoms were surveyed every 3 months. Baseline classroom levels of fine particulate matter (particulate matter with diameter of <2.5 μm [PM 2.5 ]) and black carbon (BC) were 6.3 and 0.41 μg/m 3 , respectively. When comparing the intervention to the control group, classroom PM 2.5 levels were reduced by 49% and 42% and BC levels were reduced by 58% and 55% in the first and second follow-up periods, respectively (P < .05 for all comparisons). When comparing the children randomized to intervention and control classrooms, there was a modest improvement in peak flow, but no significant changes in forced expiratory volume in 1 second (FEV 1 ) and asthma symptoms. In this pilot study, a classroom-based air cleaner intervention led to significant reductions in PM 2.5 and BC. Future large-scale studies should comprehensively evaluate the effect of school-based environmental interventions on pediatric asthma morbidity. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

EFFECTS OF ACTIVATED CHARCOAL FILTRATION AND OZONATION ON HYDROCARBON AND CARBONYL LEVELS OF AMBIENT AIR USED IN CONTROLLED-EXPOSURE CHAMBER STUDIES OF AIR POLLUTANT HUMAN HEALTH EFFECTS

EPA Science Inventory

Air sampling experiments were done in 1985, 1987, and 1993 at the human-exposure chamber facility of the U.S. EPA Health Effects Research Laboratory in Chapel Hill, NC. easurements of VOC's by GC-FID and aldehyde measurements by the DNPH silica gel cartridge method were made, com...

Controlling air pollution from passenger ferries: cost-effectiveness of seven technological options.

PubMed

Farrell, Alexander E; Corbett, James J; Winebrake, James J

2002-12-01

Continued interest in improving air quality in the United States along with renewed interest in the expansion of urban passenger ferry service has created concern about air pollution from ferry vessels. This paper presents a methodology for estimating the air pollution emissions from passenger ferries and the costs of emissions control strategies. The methodology is used to estimate the emissions and costs of retrofitting or re-powering ferries with seven technological options (combinations of propulsion and emission control systems) onto three vessels currently in service in San Francisco Bay. The technologies include improved engine design, cleaner fuels (including natural gas), and exhaust gas cleanup devices. The three vessels span a range of ages and technologies, from a 25-year-old monohull to a modern, high-speed catamaran built only four years ago. By looking at a range of technologies, vessel designs, and service conditions, a sense of the broader implications of controlling emissions from passenger ferries across a range of vessels and service profiles is provided. Tier 2-certified engines are the most cost-effective choice, but all options are cost-effective relative to other emission control strategies already in place in the transportation system.

Cost-effective retrofit technology for reducing peak power demand in small and medium commercial buildings

DOE PAGES

Nutaro, James J.; Fugate, David L.; Kuruganti, Teja; ...

2015-05-27

We describe a cost-effective retrofit technology that uses collective control of multiple rooftop air conditioning units to reduce the peak power consumption of small and medium commercial buildings. The proposed control uses a model of the building and air conditioning units to select an operating schedule for the air conditioning units that maintains a temperature set point subject to a constraint on the number of units that may operate simultaneously. A prototype of this new control system was built and deployed in a large gymnasium to coordinate four rooftop air conditioning units. Based on data collected while operating this prototype,more » we estimate that the cost savings achieved by reducing peak power consumption is sufficient to repay the cost of the prototype within a year.« less

Workload and Performance in Air Traffic Control: Exploring the Influence of Levels of Automation and Variation in Task Demand

NASA Technical Reports Server (NTRS)

Edwards, Tamsyn El; Martin, Lynne; Bienert, Nancy; Mercer, Joey

2017-01-01

In air traffic control, task demand and workload have important implications for the safety and efficiency of air traffic. Task demand is dynamic, however, research on demand transitions and associated controller perception and performance is limited. In addition, there is a comparatively restricted understanding of the influence of task demand transitions on workload and performance, in association with automation. This study used an air traffic control simulation to investigate the influence of task demand transitions and two conditions of varying automation, on workload and efficiency-related performance. Findings showed that a both the direction of the task demand variation, and the amount of automation, influenced the relationship between workload and performance. Further research is needed to enhance understanding of demand transition and workload history effects on operator experience and performance, in both air traffic control and other safety-critical domains.

Yaw rate control of an air bearing vehicle

NASA Technical Reports Server (NTRS)

Walcott, Bruce L.

1989-01-01

The results of a 6 week project which focused on the problem of controlling the yaw (rotational) rate the air bearing vehicle used on NASA's flat floor facility are summarized. Contained within is a listing of the equipment available for task completion and an evaluation of the suitability of this equipment. The identification (modeling) process of the air bearing vehicle is detailed as well as the subsequent closed-loop control strategy. The effectiveness of the solution is discussed and further recommendations are included.

Effect of increased groundwater viscosity on the remedial performance of surfactant-enhanced air sparging.

PubMed

Choi, Jae-Kyeong; Kim, Heonki; Kwon, Hobin; Annable, Michael D

2018-03-01

The effect of groundwater viscosity control on the performance of surfactant-enhanced air sparging (SEAS) was investigated using 1- and 2-dimensional (1-D and 2-D) bench-scale physical models. The viscosity of groundwater was controlled by a thickener, sodium carboxymethylcellulose (SCMC), while an anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), was used to control the surface tension of groundwater. When resident DI water was displaced with a SCMC solution (500 mg/L), a SDBS solution (200 mg/L), and a solution with both SCMC (500 mg/L) and SDBS (200 mg/L), the air saturation for sand-packed columns achieved by air sparging increased by 9.5%, 128%, and 154%, respectively, (compared to that of the DI water-saturated column). When the resident water contained SCMC, the minimum air pressure necessary for air sparging processes increased, which is considered to be responsible for the increased air saturation. The extent of the sparging influence zone achieved during the air sparging process using the 2-D model was also affected by viscosity control. Larger sparging influence zones (de-saturated zone due to air injection) were observed for the air sparging processes using the 2-D model initially saturated with high-viscosity solutions, than those without a thickener in the aqueous solution. The enhanced air saturations using SCMC for the 1-D air sparging experiment improved the degradative performance of gaseous oxidation agent (ozone) during air sparging, as measured by the disappearance of fluorescence (fluorescein sodium salt). Based on the experimental evidence generated in this study, the addition of a thickener in the aqueous solution prior to air sparging increased the degree of air saturation and the sparging influence zone, and enhanced the remedial potential of SEAS for contaminated aquifers. Copyright © 2018 Elsevier B.V. All rights reserved.

Water reuse systems: A review of the principal components

USGS Publications Warehouse

Lucchetti, G.; Gray, G.A.

1988-01-01

Principal components of water reuse systems include ammonia removal, disease control, temperature control, aeration, and particulate filtration. Effective ammonia removal techniques include air stripping, ion exchange, and biofiltration. Selection of a particular technique largely depends on site-specific requirements (e.g., space, existing water quality, and fish densities). Disease control, although often overlooked, is a major problem in reuse systems. Pathogens can be controlled most effectively with ultraviolet radiation, ozone, or chlorine. Simple and inexpensive methods are available to increase oxygen concentration and eliminate gas supersaturation, these include commercial aerators, air injectors, and packed columns. Temperature control is a major advantage of reuse systems, but the equipment required can be expensive, particularly if water temperature must be rigidly controlled and ambient air temperature fluctuates. Filtration can be readily accomplished with a hydrocyclone or sand filter that increases overall system efficiency. Based on criteria of adaptability, efficiency, and reasonable cost, we recommend components for a small water reuse system.

INTERDEPENDENCIES OF MULTI-POLLUTANT CONTROL SIMULATIONS IN AN AIR QUALITY MODEL

EPA Science Inventory

In this work, we use the Community Multi-Scale Air Quality (CMAQ) modeling system to examine the effect of several control strategies on simultaneous concentrations of ozone, PM_2.5, and three important HAPs: formaldehyde, acetaldehyde and benzene.

Air pollution from hot mix plants.

DOT National Transportation Integrated Search

1970-10-01

The Louisiana Air Control Commission adopted Regulation II, effective 1969, which sets stringent limits on suspended particulates. Because of the lack of knowledge concerning air pollution caused by hot mix plants within the Stake and because of the ...

Experimental characterization of the effects of pneumatic tubing on unsteady pressure measurements

NASA Technical Reports Server (NTRS)

Whitmore, Stephen A.; Lindsey, William T.; Curry, Robert E.; Gilyard, Glenn B.

1990-01-01

Advances in aircraft control system designs have, with increasing frequency, required that air data be used as flight control feedback. This condition requires that these data be measured with accuracy and high fidelity. Most air data information is provided by pneumatic pressure measuring sensors. Typically unsteady pressure data provided by pneumatic sensing systems are distorted at high frequencies. The distortion is a result of the pressure being transmitted to the pressure sensor through a length of connective tubing. The pressure is distorted by frictional damping and wave reflection. As a result, air data provided all-flush, pneumatically sensed air data systems may not meet the frequency response requirements necessary for flight control augmentation. Both lab and flight test were performed at NASA-Ames to investigate the effects of this high frequency distortion in remotely located pressure measurement systems. Good qualitative agreement between lab and flight data are demonstrated. Results from these tests are used to describe the effects of pneumatic distortion in terms of a simple parametric model.

Clean Air for Anchorage and Fairbanks: Curriculum for Grades 1-6.

ERIC Educational Resources Information Center

South East Regional Resource Center, Juneau, AK.

Through the 10 lessons in this guide, elementary school students can be introduced to the characteristics of air, methods of air pollution control, air movement, and the health effects of polluted air. A directory of field trip sites and a list of teacher resources is included. Contained in each lesson plan are a materials list, general…

Geographic Region, Weather, Pilot Age and Air Carrier Crashes: a Case-Control Study

PubMed Central

Li, Guohua; Pressley, Joyce C.; Qiang, Yandong; Grabowski, Jurek G.; Baker, Susan P.; Rebok, George W.

2009-01-01

Background Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis and commuter air carriers. Methods A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (n=373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus, recorded in the National Transportation Safety Board’s aviation crash database during 1983 through 2002, and controls (n=746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration’s aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. Results With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions [adjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35 – 7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15 – 4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.57, 95% CI 0.40 – 0.87). Neither pilot age nor total flight time was significantly associated with the risk of air carrier crashes. Conclusions The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety. PMID:19378910

Geographic region, weather, pilot age, and air carrier crashes: a case-control study.

PubMed

Li, Guohua; Pressley, Joyce C; Qiang, Yandong; Grabowski, Jurek G; Baker, Susan P; Rebok, George W

2009-04-01

Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis, and commuter air carriers. A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (N = 373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus recorded in the National Transportation Safety Board's aviation crash database during 1983 through 2002, and controls (N = 746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration's aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions ladjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35-7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15-4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.60, 95% CI 0.37-0.96). Neither pilot age nor total flight time were significantly associated with the risk of air carrier crashes. The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety.

EFFECTS OF CHANGING COALS ON THE EMISSIONS OF METAL HAZARDOUS AIR POLLUTANTS FROM THE COMBUSTION OF PULVERIZED COAL

EPA Science Inventory

The report discusses tests conducted at EPA's Air Pollution Prevention and Control Division to evaluate the effects of changing coals on emissions of metal hazardous air pollutants from coal-fired boilers. Six coals were burned in a 29 kW (100,000 Btu/hr) down-fired combustor und...

Modeled Effectiveness of Ventilation with Contaminant Control Devices on Indoor Air Quality in a Swine Farrowing Facility

PubMed Central

Anthony, T. Renée; Altmaier, Ralph; Park, Jae Hong; Peters, Thomas M.

2016-01-01

Because adverse health effects experienced by swine farm workers in concentrated animal feeding operations (CAFOs) have been associated with exposure to dust and gases, efforts to reduce exposures are warranted, particularly in winter seasons when exposures increase due to decreased ventilation. Simulation of air quality and operating costs for ventilating swine CAFO, including treating and recirculating air through a farrowing room, was performed using mass and energy balance equations over a 90-day winter season. System operation required controlling heater operation to achieve room temperatures optimal to ensure animal health (20 to 22.5°C). Five air pollution control devices, four room ventilation rates, and five recirculation patterns were examined. Inhalable dust concentrations were easily reduced using standard industrial air pollution control devices, including a cyclone, filtration, and electrostatic precipitator. Operating ventilation systems at 0.94 m3 s−1 (2000 cfm) with 75 to 100% recirculation of treated air from cyclone, electrostatic precipitator, and shaker dust filtration system achieves adequate particle control with operating costs under $1.00 per pig produced ($0.22 to 0.54), although carbon dioxide (CO2) concentrations approach 2000 ppm using in-room ventilated gas fired heaters. In no simulation were CO2 concentrations below industry recommended concentrations (1540 ppm), but alternative heating devices could reduce CO2 to acceptable concentrations. While this investigation does not represent all production swine farrowing barns, which differ in characteristics including room dimensions and swine occupancy, the simulation model and ventilation optimization methods can be applied to other production sites. This work shows that ventilation may be a cost-effective control option in the swine industry to reduce exposures. PMID:24433305

Modeled effectiveness of ventilation with contaminant control devices on indoor air quality in a swine farrowing facility.

PubMed

Anthony, T Renée; Altmaier, Ralph; Park, Jae Hong; Peters, Thomas M

2014-01-01

Because adverse health effects experienced by swine farm workers in concentrated animal feeding operations (CAFOs) have been associated with exposure to dust and gases, efforts to reduce exposures are warranted, particularly in winter seasons when exposures increase due to decreased ventilation. Simulation of air quality and operating costs for ventilating swine CAFO, including treating and recirculating air through a farrowing room, was performed using mass and energy balance equations over a 90-day winter season. System operation required controlling heater operation to achieve room temperatures optimal to ensure animal health (20 to 22.5 °C). Five air pollution control devices, four room ventilation rates, and five recirculation patterns were examined. Inhalable dust concentrations were easily reduced using standard industrial air pollution control devices, including a cyclone, filtration, and electrostatic precipitator. Operating ventilation systems at 0.94 m3 s(-1) (2000 cfm) with 75 to 100% recirculation of treated air from cyclone, electrostatic precipitator, and shaker dust filtration system achieves adequate particle control with operating costs under $1.00 per pig produced ($0.22 to 0.54), although carbon dioxide (CO2) concentrations approach 2000 ppm using in-room ventilated gas fired heaters. In no simulation were CO2 concentrations below industry recommended concentrations (1540 ppm), but alternative heating devices could reduce CO2 to acceptable concentrations. While this investigation does not represent all production swine farrowing barns, which differ in characteristics including room dimensions and swine occupancy, the simulation model and ventilation optimization methods can be applied to other production sites. This work shows that ventilation may be a cost-effective control option in the swine industry to reduce exposures.

Air-Abrasive Disinfection of Implant Surfaces in a Simulated Model of Periimplantitis.

PubMed

Quintero, David George; Taylor, Robert Bonnie; Miller, Matthew Braden; Merchant, Keith Roshanali; Pasieta, Scott Anthony

2017-06-01

This in vitro study aimed to evaluate the ability of air-powder abrasion to decontaminate dental implants. Twenty-six implants were inoculated with a Streptococcus sanguinis biofilm media in a novel periimplantitis defect model. Six implants served as controls, and 20 implants were disinfected with either the Cavitron JET Plus or the AIR-FLOW PERIO air-powder abrasion units. Residual bacteria were cultured, and colony forming units (CFUs) were totaled at 24 hours. As expected, negative control implant cultures showed no evidence of viable bacteria. Bacterial growth was observed on all positive control cultures, whereas only 15% of the experimental cultures displayed evidence of viable bacteria. The average CFU per streak for the positive control was 104 compared with a maximum of 10 and 4 CFUs for the Cavitron JET Plus and AIR-FLOW PERIO, respectively. There was a 99.9% reduction in bacteria for both air-powder abrasion instruments. Air-powder abrasion is an effective technique for the decontamination of dental implants, and the Cavitron JET Plus and AIR-FLOW PERIO are equally successful at eliminating viable bacteria from implant surfaces.

A Review of Air Pollutant Damage to Materials

EPA Science Inventory

Report prepared as U.S. contribution to Panel 3 of NATO Committee on Challenges of Modern Society Pilot Study on Air Pollution Control Strategies and Impact Modeling. Panel 3 focuses on air pollutant impact and will publish 4 reports on air pollutants effects; this is the first i...

Effectiveness of national air pollution control policies on the air quality in metropolitan areas of China.

PubMed

Wang, Shuxiao; Xing, Jia; Zhao, Bin; Jang, Carey; Hao, Jiming

2014-01-01

Understanding the effectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the effectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide (SO2) control policy during the 11th Five Year Plan period (2006-2010) had succeeded in reducing the national SO2 emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2 and sulfate (SO4(2-)) concentrations by 13%-15% and 8%-10% respectively over east China. The nitrogen oxides (NO(x)) control policy during the 12th Five Year Plan period (2011-2015) targets the reduction of the national NO(x) emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NO(x) emission will reduce the ambient nitrogen dioxide (NO2), nitrate (NO3(-)), 1-hr maxima ozone (O3) concentrations and total nitrogen deposition by 8%, 3%-14%, 2% and 2%-4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3(-), 1-hr maxima O(3 concentrations and total nitrogen deposition by 2%-4%, 1%-6%, 0-2% and 1%-2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.

Handle With Care: An Air Pollution Module for Sixth, Seventh, and Eighth Grade Teachers of Health Education, Science, and Other Subject Areas.

ERIC Educational Resources Information Center

Guerin, Dolores

Presented is a module on air pollution for sixth through eighth graders. Six subsections address the many aspects of air and air pollution: (1) sensory awareness, (2) the nature of the atmosphere, (3) air pollution's effects on health and property, (4) values conflicts, (5) air quality control, and (6) individual responsibility. Learning…

Waveform-controlled terahertz radiation from the air filament produced by few-cycle laser pulses.

PubMed

Bai, Ya; Song, Liwei; Xu, Rongjie; Li, Chuang; Liu, Peng; Zeng, Zhinan; Zhang, Zongxin; Lu, Haihe; Li, Ruxin; Xu, Zhizhan

2012-06-22

Waveform-controlled terahertz (THz) radiation is of great importance due to its potential application in THz sensing and coherent control of quantum systems. We demonstrated a novel scheme to generate waveform-controlled THz radiation from air plasma produced when carrier-envelope-phase (CEP) stabilized few-cycle laser pulses undergo filamentation in ambient air. We launched CEP-stabilized 10 fs-long (~1.7 optical cycles) laser pulses at 1.8 μm into air and found that the generated THz waveform can be controlled by varying the filament length and the CEP of driving laser pulses. Calculations using the photocurrent model and including the propagation effects well reproduce the experimental results, and the origins of various phase shifts in the filament are elucidated.

76 FR 10249 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Revisions To Control...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-24

... Container rule as an ozone control strategy from the Texas SIP for the Control of Ozone Air Pollution. In the submittal, Texas demonstrates that Federal portable fuel container standards promulgated by EPA in... Portable Fuel Container Regulations IV. What is the effect of this action? V. Final Action VI. Statutory...

High reduction of ozone and particulate matter during the 2016 G-20 summit in Hangzhou by forced emission controls of industry and traffic

EPA Science Inventory

Many regions in China experience air pollution episodes because of the rapid urbanization and industrialization over the past decades. Here we analyzed the effect of emission controls implemented during the G-20 2016 Hangzhou summit on air quality. Emission controls included a fo...

CAPSULE REPORT: SOURCES AND AIR EMISSION CONTROL TECHNOLOGIES AT WASTE MANAGEMENT FACILITIES

EPA Science Inventory

The chemicals processed during waste management operations can volatilize into the atmosphere and cause carcinogenic or other toxic effects or contribute to ozone formation. Regulations have been developed to control air emissions from these operations. The EPA has promulgated st...

Will joint regional air pollution control be more cost-effective? An empirical study of China's Beijing-Tianjin-Hebei region.

PubMed

Wu, Dan; Xu, Yuan; Zhang, Shiqiu

2015-02-01

By following an empirical approach, this study proves that joint regional air pollution control (JRAPC) in the Beijing-Tianjin-Hebei region will save the expense on air pollution control compared with a locally-based pollution control strategy. The evidences below were found. (A) Local pollutant concentration in some of the cities is significantly affected by emissions from their surrounding areas. (B) There is heterogeneity in the marginal pollutant concentration reduction cost among various districts as a result of the cities' varying contribution of unit emission reduction to the pollutant concentration reduction, and their diverse unit cost of emission reduction brought about by their different industry composition. The results imply that the cost-efficiency of air pollution control will be improved in China if the conventional locally based regime of air pollution control can shift to a regionally based one. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Controlling a hurricane by altering its internal climate

NASA Astrophysics Data System (ADS)

Mardhekar, D.

2010-09-01

Atmospheric hazards, like the fury of a hurricane, can be controlled by altering its internal climate. The hurricane controlling technique suggested is eco-friendly, compatible with hurricane size, has a sound scientific base and is practically possible. The key factor is a large scale dilution of the hurricane fuel, vapour, in the eye wall and spiral rain bands where condensation causing vapor volume reduction (a new concept which can be explained by Avogadro's law) and latent heat release drive the storm. This can be achieved by installing multiple storage tanks containing dry liquefied air on the onshore and offshore coastal regions and islands, preferably underground, in the usual path of a hurricane. Each storage tank is designed to hold and release dry liquefied air of around 100,000 tons. Satellite tracking of hurricanes can locate the eye wall and the spiral rain bands. The installed storage tanks coming under these areas will rapidly inject dry air in huge quantities thereby diluting the vapour content of the vapour-rich air in the eye wall and in the spiral rain bands. This will result in reduced natural input of vapour-rich air, reduced release of latent heat, reduced formation of the low pressure zone due to condensation and volume reduction of the vapor, expansion of the artificially introduced dry air as it goes up occupying a larger space with the diluted fuel, absorption of energy from the system by low temperature of the artificially introduced air. It will effect considerable condensation of the vapor near the sea surface thus further starving the hurricane of its fuel in its engine. Seeding materials, or microscopic dust as suggested by Dr. Daniel Rosenfeld in large quantities may also be introduced via the flow of the injected dry air in order to enhance the hurricane controlling ability. All the above factors are in favour of retarding the hurricane's wind speed and power. The sudden weakening of hurricane Lili was found to be partially caused by the natural input of drier air. We are artificially introducing completely dry air in large quantities (perhaps the dry air release is from 100,000 tons X 50 tanks or 100 tanks or even more tanks, whatever comes under the defined areas) and that too along with seeding materials if required. Importantly, these mega introductions are directly into the proper areas of a hurricane. Optionally, the dry air introduction may be done anywhere in the core of a hurricane. We can even tame a hurricane in a controlled manner by controlling the volumes of the release of the dry gas, the seeding materials and the locations of the release so that fresh water in the form of rains can come on land simultaneously limiting the destruction. Most importantly the dissipation of the hurricanes hitting the coastal regions can be effectively accelerated to control the destruction by introducing the dry air from the coastal region tanks. Here the land effect and simultaneous introduction of the dry air will give a synergic effect.

Ambient Air Pollution and Biomarkers of Health Effect.

PubMed

Yang, Di; Yang, Xuan; Deng, Furong; Guo, Xinbiao

2017-01-01

Recently, the air pollution situation of our country is very serious along with the development of urbanization and industrialization. Studies indicate that the exposure of air pollution can cause a rise of incidence and mortality of many diseases, such as chronic obstructive pulmonary disease (COPD), asthma, myocardial infarction, and so on. However, there is now growing evidence showing that significant air pollution exposures are associated with early biomarkers in various systems of the body. In order to better prevent and control the damage effect of air pollution, this article summarizes comprehensively epidemiological studies about the bad effects on the biomarkers of respiratory system, cardiovascular system, and genetic and epigenetic system exposure to ambient air pollution.

Servo-control for maintaining abdominal skin temperature at 36C in low birth weight infants.

PubMed

Sinclair, J C

2000-01-01

Randomized trials have shown that the neonatal mortality rate of low birth-weight babies can be reduced by keeping them warm. For low birth-weight babies nursed in incubators, warm conditions may be achieved either by heating the air to a desired temperature, or by servo-controlling the baby's body temperature at a desired set-point. In low birth weight infants, to determine the effect on death and other important clinical outcomes of targeting body temperature rather than air temperature as the end-point of control of incubator heating. Standard search strategy of the Cochrane Neonatal Collaborative Review Group. Randomized or quasi-randomized trials which test the effects of having the heat output of the incubator servo-controlled from body temperature compared with setting a constant incubator air temperature. Trial methodologic quality was systematically assessed. Outcome measures included death, timing of death, cause of death, and other clinical outcomes. Categorical outcomes were analyzed using relative risk and risk difference. Meta-analysis assumed a fixed effect model. Compared to setting a constant incubator air temperature of 31.8C, servo-control of abdominal skin temperature at 36C reduces the neonatal death rate among low birth weight infants: relative risk 0.72 (95% CI 0.54, 0.97); risk difference -12.7% (95% CI -1.6, -23.9). This effect is even greater among VLBW infants. During at least the first week after birth, low birth weight babies should be provided with a carefully regulated thermal environment that is near the thermoneutral point. For LBW babies in incubators, this can be achieved by adjusting incubator temperature to maintain an anterior abdominal skin temperature of at least 36C, using either servo-control or frequent manual adjustment of incubator air temperature.

40 CFR 52.1528 - Control strategy: Carbon monoxide.

Code of Federal Regulations, 2012 CFR

2012-07-01

... effect through the year 2020, as required by the Clean Air Act. If the area records a violation of the... that the maintenance plan will remain in effect through the year 2020, as required by the Clean Air Act...

40 CFR 52.1528 - Control strategy: Carbon monoxide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... effect through the year 2020, as required by the Clean Air Act. If the area records a violation of the... that the maintenance plan will remain in effect through the year 2020, as required by the Clean Air Act...

Impacts of the Convention on Long-range Transboundary Air Pollution on air quality in Europe.

PubMed

Bull, Keith; Johansson, Matti; Krzyzanowski, Michal

2008-01-01

The Convention on Long-range Transboundary Air Pollution has been one of the main ways of protecting the environment in Europe from air pollution. This convention has successfully bridged different political systems even through times of political change, and is a prime example of what can be achieved through intergovernmental cooperation. Through creating an effective framework for controlling and reducing the damage to human health and the environment from transboundary air pollution, this convention has proved successful. This article considers the development of the convention and its work on adverse air pollution effects, in particular on activities related to quantifying effects on human health as carried out by the convention's joint (with WHO) Task Force on the Health Effects of Air Pollution (Task Force on Health), and concludes with some indications of the convention's future priorities.

Effect of Intake Air Filter Condition on Light-Duty Gasoline Vehicles

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

Thomas, John F; Huff, Shean P; West, Brian H

2012-01-01

Proper maintenance can help vehicles perform as designed, positively affecting fuel economy, emissions, and the overall drivability. This effort investigates the effect of one maintenance factor, intake air filter replacement, with primary focus on vehicle fuel economy, but also examining emissions and performance. Older studies, dealing with carbureted gasoline vehicles, have indicated that replacing a clogged or dirty air filter can improve vehicle fuel economy and conversely that a dirty air filter can be significantly detrimental to fuel economy. The effect of clogged air filters on the fuel economy, acceleration and emissions of five gasoline fueled vehicles is examined. Fourmore » of these were modern vehicles, featuring closed-loop control and ranging in model year from 2003 to 2007. Three vehicles were powered by naturally aspirated, port fuel injection (PFI) engines of differing size and cylinder configuration: an inline 4, a V6 and a V8. A turbocharged inline 4-cylinder gasoline direct injection (GDI) engine powered vehicle was the fourth modern gasoline vehicle tested. A vintage 1972 vehicle equipped with a carburetor (open-loop control) was also examined. Results reveal insignificant fuel economy and emissions sensitivity of modern vehicles to air filter condition, but measureable effects on the 1972 vehicle. All vehicles experienced a measured acceleration performance penalty with clogged intake air filters.« less

Long-term indoor air conditioner filtration and cardiovascular health: A randomized crossover intervention study.

PubMed

Chuang, Hsiao-Chi; Ho, Kin-Fai; Lin, Lian-Yu; Chang, Ta-Yuan; Hong, Gui-Bing; Ma, Chi-Ming; Liu, I-Jung; Chuang, Kai-Jen

2017-09-01

The association of short-term air pollution filtration with cardiovascular health has been documented. However, the effect of long-term indoor air conditioner filtration on the association between air pollution and cardiovascular health is still unclear. We recruited 200 homemakers from Taipei and randomly assigned 100 of them to air filtration or control intervention; six home visits were conducted per year from 2013 to 2014. The participants under air filtration intervention during 2013 were reassigned to control intervention in 2014. The air pollution measurements consisted of particulate matter less than or equal to 2.5μm in diameter (PM 2.5 ) and total volatile organic compounds (VOCs); blood pressure was monitored for each participant during each visit. The following morning, blood samples were collected after air pollution monitoring. The blood samples were used to analyze biological markers, including high sensitivity-C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG) and fibrinogen. Household information, including cleaning, cooking, and air conditioning, was collected by a questionnaire. Mixed-effects models were used to investigate the associations among air pollution measurements, blood pressure and biological markers. The results showed that increased levels of PM 2.5 and total VOCs were associated with increased hs-CRP, 8-OHdG and blood pressure. The health variables were higher among participants in the control intervention phase than among those in the air filtration intervention phase. We concluded that air pollution exposure was associated with systemic inflammation, oxidative stress and elevated blood pressure. The long-term filtration of air pollution with an air conditioner filter was associated with cardiovascular health of adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

DETERMINING INHALATION RISK -- TOOLS FOR ASSESSING HAZARD.

EPA Science Inventory

The Clean Air Act focuses on reduction of the potential for specific air pollutants to cause adverse health effects. Implementation of standards to control release of the 188 hazardous air pollutants (HAPs) requires the Environmental Protection Agency (EPA) to evaluate the healt...

76 FR 72626 - Approval and Promulgation of Air Quality Implementation Plans; Delaware; Amendments to the...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

.... (See section 307(b)(2).) List of Subjects in 40 CFR part 52 Environmental protection, Air pollution... Promulgation of Air Quality Implementation Plans; Delaware; Amendments to the Control of Volatile Organic... accordance with the requirements of the Clean Air Act (CAA). DATES: Effective Date: This final rule is...

Trade transport and environment linkages at the U.S.-Mexico border: which policies matter?

PubMed

Fernandez, Linda; Das, Monica

2011-03-01

We apply a fixed-effects model to examine the impact of trade and environmental policies on air quality at ports along the U.S.-Mexico border. We control for other factors influencing air quality, such as air quality of cities near the border, volume of traffic flows and congestion. Results show the air quality improved after 2004, when the diesel engine policy was applied. We see mixed results for the trade policy, whose implementation time varies across ports along the international border. Controlling for air quality in cities near the border is essential for assessing the policy contributions to air quality. Copyright © 2010. Published by Elsevier Ltd.

Effects of ceiling-mounted HEPA-UV air filters on airborne bacteria concentrations in an indoor therapy pool building.

PubMed

Kujundzic, Elmira; Zander, David A; Hernandez, Mark; Angenent, Largus T; Henderson, David E; Miller, Shelly L

2005-02-01

The purpose of this study was to assess the effectiveness of a new generation of high-volume, ceiling-mounted high-efficiency particulate air (HEPA)-ultraviolet (UV) air filters (HUVAFs) for their ability to remove or inactivate bacterial aerosol. In an environmentally controlled full-scale laboratory chamber (87 m3), and an indoor therapy pool building, the mitigation ability of air filters was assessed by comparing concentrations of total bacteria, culturable bacteria, and airborne endotoxin with and without the air filters operating under otherwise similar conditions. Controlled chamber tests with pure cultures of aerosolized Mycobacterium parafortuitum cells showed that the HUVAF unit tested provided an equivalent air-exchange rate of 11 hr(-1). Using this equivalent air-exchange rate as a design basis, three HUVAFs were installed in an indoor therapy pool building for bioaerosol mitigation, and their effectiveness was studied over a 2-year period. The HUVAFs reduced concentrations of culturable bacteria by 69 and 80% during monitoring periods executed in respective years. The HUVAFs reduced concentrations of total bacteria by 12 and 76% during the same monitoring period, respectively. Airborne endotoxin concentrations were not affected by the HUVAF operation.

Composting on Mars or the Moon: II. Temperature feedback control with top-wise introduction of waste material and air

NASA Technical Reports Server (NTRS)

Finstein, M. S.; Hogan, J. A.; Sager, J. C.; Cowan, R. M.; Strom, P. F.; Janes, H. W. (Principal Investigator)

1999-01-01

Whereas Earth-based composting reactors that effectively control the process are batch operations with bottom-to-top airflow, in extraterrestrial application both the fresh waste and the air need to be introduced from above. Stabilized compost and used air would exit below. This materials flow pattern permits the addition of waste whenever generated, obviating the need for multiple reactors, and the incorporation of a commode in the lid. Top loading in turn dictates top-down aeration, so that the most actively decomposing material (greatest need for heat removal and O2 replenishment) is first encountered. This novel material and aeration pattern was tested in conjunction with temperature feedback process control. Reactor characteristics were: working, volume, 0.15 m3; charge, 2 kg dry biomass per day (comparable to a 3-4 person self-sufficient bioregenerative habitat); retention time, 7 days. Judging from temperature profile, O2 level, air usage, pressure head loss, moisture, and odor, the system was effectively controlled over a 35-day period. Dry matter disappearance averaged 25% (10-42%). The compost product was substantially, though not completely, stabilized. This demonstrates the compatibility of top-wise introduction of waste and air with temperature feedback process control.

Composting on Mars or the Moon: II. Temperature feedback control with top-wise introduction of waste material and air.

PubMed

Finstein, M S; Hogan, J A; Sager, J C; Cowan, R M; Strom, P F

1999-01-01

Whereas Earth-based composting reactors that effectively control the process are batch operations with bottom-to-top airflow, in extraterrestrial application both the fresh waste and the air need to be introduced from above. Stabilized compost and used air would exit below. This materials flow pattern permits the addition of waste whenever generated, obviating the need for multiple reactors, and the incorporation of a commode in the lid. Top loading in turn dictates top-down aeration, so that the most actively decomposing material (greatest need for heat removal and O2 replenishment) is first encountered. This novel material and aeration pattern was tested in conjunction with temperature feedback process control. Reactor characteristics were: working, volume, 0.15 m3; charge, 2 kg dry biomass per day (comparable to a 3-4 person self-sufficient bioregenerative habitat); retention time, 7 days. Judging from temperature profile, O2 level, air usage, pressure head loss, moisture, and odor, the system was effectively controlled over a 35-day period. Dry matter disappearance averaged 25% (10-42%). The compost product was substantially, though not completely, stabilized. This demonstrates the compatibility of top-wise introduction of waste and air with temperature feedback process control.

Effects of air pollutants on lemons and naval oranges

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

Thompson, C.R.

1968-01-01

The effects of photochemical oxidant and fluoride air pollutants on lemon and orange trees were evaluated in a series of greenhouse experiments. Trees exposed to the pollutants show increased lead drop and decreased fruit yield in comparison to controls.

Air pollution control system research: An iterative approach to developing affordable systems

NASA Technical Reports Server (NTRS)

Watt, Lewis C.; Cannon, Fred S.; Heinsohn, Robert J.; Spaeder, Timothy A.

1995-01-01

This paper describes a Strategic Environmental Research and Development Program (SERDP) funded project led jointly by the Marine Corps Multi-Commodity Maintenance Centers, and the Air and Energy Engineering Research Laboratory (AEERL) of the USEPA. The research focuses on paint booth exhaust minimization using recirculation, and on volatile organic compound (VOC) oxidation by the modules of a hybrid air pollution control system. The research team is applying bench, pilot and full scale systems to accomplish the goals of reduced cost and improved effectiveness of air treatment systems for paint booth exhaust.

Relationship of oxygen dose to angiogenesis induction in irradiated tissue

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

Marx, R.E.; Ehler, W.J.; Tayapongsak, P.

1990-11-01

This study was accomplished in an irradiated rabbit model to assess the angiogenic properties of normobaric oxygen and hyperbaric oxygen as compared with air-breathing controls. Results indicated that normobaric oxygen had no angiogenic properties above normal revascularization of irradiated tissue than did air-breathing controls (p = 0.89). Hyperbaric oxygen demonstrated an eight- to ninefold increased vascular density over both normobaric oxygen and air-breathing controls (p = 0.001). Irradiated tissue develops a hypovascular-hypocellular-hypoxic tissue that does not revascularize spontaneously. Results failed to demonstrate an angiogenic effect of normobaric oxygen. It is suggested that oxygen in this sense is a drug requiringmore » hyperbaric pressures to generate therapeutic effects on chronically hypovascular irradiated tissue.« less

A Distributed Simulation Facility to Support Human Factors Research in Advanced Air Transportation Technology

NASA Technical Reports Server (NTRS)

Amonlirdviman, Keith; Farley, Todd C.; Hansman, R. John, Jr.; Ladik, John F.; Sherer, Dana Z.

1998-01-01

A distributed real-time simulation of the civil air traffic environment developed to support human factors research in advanced air transportation technology is presented. The distributed environment is based on a custom simulation architecture designed for simplicity and flexibility in human experiments. Standard Internet protocols are used to create the distributed environment, linking all advanced cockpit simulator, all Air Traffic Control simulator, and a pseudo-aircraft control and simulation management station. The pseudo-aircraft control station also functions as a scenario design tool for coordinating human factors experiments. This station incorporates a pseudo-pilot interface designed to reduce workload for human operators piloting multiple aircraft simultaneously in real time. The application of this distributed simulation facility to support a study of the effect of shared information (via air-ground datalink) on pilot/controller shared situation awareness and re-route negotiation is also presented.

Effects on well-being of investing in cleaner air in India.

PubMed

Sanderson, Warren; Striessnig, Erich; Schöpp, Wolfgang; Amann, Markus

2013-01-01

Over the past decade, India has experienced rapid economic growth along with increases in levels of air pollution. Our goal is to examine how alternative policies for air pollution abatement affect well-being there. In particular, we estimate the effects of policies to reduce the levels of ambient fine particulates (PM2.5), which are especially harmful to human health, on well-being, quantified using the United Nations' human development index (HDI). Two of the three dimensions of this index are based on gross domestic product (GDP) per capita and life expectancy. Our approach allows reductions in PM2.5 to affect both of them. In particular, economic growth is affected negatively through the costs of the additional pollution control measures and positively through the increased productivity of the population. We consider three scenarios of PM2.5 abatement, corresponding to no further control, current Indian legislation, and current European legislation. The overall effect in both control scenarios is that growth in GDP is virtually unaffected relative to the case of no further controls, life expectancy is higher, and well-being, as measured by the HDI, is improved. In India, air pollution abatement investments clearly improve well-being.

Research on the operation control strategy of the cooling ceiling combined with fresh air system

NASA Astrophysics Data System (ADS)

Huang, Tao; Li, Hao

2018-03-01

The cooling ceiling combined with independent fresh air system was built by TRNSYS. And the cooling effects of the air conditioning system of an office in Beijing in a summer typical day were simulated. Based on the “variable temperature” control strategy, the operation strategy of “variable air volume auxiliary adjustment” was put forward. The variation of the indoor temperature, the indoor humidity, the temperature of supplying water and the temperature of returning water were simulated under the two control strategies. The energy consumption of system during the whole summer was compared by utilizing the two control strategies, and the indoor thermal comfort was analyzed. The optimal control strategy was proposed under the condition that the condensation on the surface of the cooling ceiling is not occurred and the indoor thermal comfort is satisfied.

The selection of air traffic control specialists. I., History and review of contributions by the Civil Aeromedical Institute.

DOT National Transportation Integrated Search

1980-06-01

For two decades the FAA Civil Aeromedical Institute (CAMI) has engaged in active research programs exploring most aspects of the problems of effectively selecting air traffic control specialists (ATCSs) for the FAA. The results of those efforts have ...

Sweaty Palms! Virtual Reality Applied to Training.

ERIC Educational Resources Information Center

Treiber, Karin

A qualitative case study approach was used to identify the psychosocial effects of the high-fidelity, virtual reality simulation provided in the college-level air traffic control (ATC) training program offered at the Minnesota Air Traffic Control Training Center and to evaluate the applicability of virtual reality to academic/training situations.…

Challenges for the Baltic Sea Regional Stability

DTIC Science & Technology

2013-03-01

statements show that Russia still has ambitions to expand her influence and control over the Baltic Sea region. Reduction of U.S. military presence in Europe...combat support units during 2013-2015, such as A-10 squadron at Spangdahlem Air Base in Germany, the 603rd Air Control Squadron at Aviano Air Base in ...other hand, such continued cooperation in the period of defense austerity would be the main option for sharing and reaching cost effectiveness

Demand controlled ventilating systems: Sensor market survey. Energy conservation in buildings and community systems programme, annex 18, December 1991

NASA Astrophysics Data System (ADS)

Raatschen, W.; Sjoegren, M.

The subject of indoor and outdoor air quality has generated a great deal of attention in many countries. Areas of concern include outgassing of building materials as well as occupant-generated pollutants such as carbon dioxide, moisture, and odors. Progress has also been made towards addressing issues relating to the air tightness of the building envelope. Indoor air quality studies indicate that better control of supply flow rates as well as the air distribution pattern within buildings are necessary. One method of maintaining good indoor air quality without extensive energy consumption is to control the ventilation rate according to the needs and demands of the occupants, or to preserve the building envelope. This is accomplished through the use of demand controlled ventilating (DCV) systems. The specific objective of Annex 18 is to develop guidelines for demand controlled ventilating systems based on state of the art analyses, case studies on ventilation effectiveness, and proposed ventilation rates for different users in domestic, office, and school buildings.

Containing air pollution and traffic congestion: Transport policy and the environment in Singapore

NASA Astrophysics Data System (ADS)

Chin, Anthony T. H.

Land transportation remains one of the main contributors of noise and air pollution in urban areas. This is in addition to traffic congestion and accidents which result in the loss of productive activity. While there is a close relationship between traffic volumes and levels of noise and air pollution, transport authorities often assume that solving traffic congestion would reduce noise and air pollutant levels. Tight control over automobile ownership and use in Singapore has contributed in improving traffic flows, travel speeds and air quality. The adoption of internationally accepted standards on automobile emissions and gasoline have been effective in reducing air pollution from motor vehicles. Demand management measures have largely focused on controlling the source of traffic congestion, i.e. private automobile ownership and its use especially within the Central Business District during the day. This paper reviews and analyzes the effectiveness of two measures which are instrumental in controlling congestion and automobile ownership, i.e. road pricing and the vehicle quota scheme (VQS). While these measures have been successful in achieving desired objectives, it has also led to the spreading of traffic externalities to other roads in the network, loss in consumer welfare and rent seeking by automobile traders.

Source Apportionment of Final Particulate Matterin North China Plain based on Air Quality Modeling

NASA Astrophysics Data System (ADS)

Xing, J.; Wu, W.; Chang, X.; Wang, S.; Hao, J.

2016-12-01

Most Chinese cities in North China Plain are suffering from serious air pollution. To develop the regional air pollution control policies, we need to identify the major source contributions to such pollution and to design the control policy which is accurate, efficient and effective. This study used the air quality model with serval advanced technologies including ISAM and ERSM, to assess the source contributions from individual pollutants (incl. SO2, NOx, VOC, NH3, primary PM), sectors (incl. power plants, industry, transportation and domestic), and regions (Beijing, Hebei, Tianjing and surrounding provinces). The modeling period is two months in 2012 as January and July which represent winter and summer respectively. The non-linear relationship between air pollutant emissions and air quality will be addressed, and the integrated control of multi-pollutants and multi-regions in China will be suggested.

Combined comfort model of thermal comfort and air quality on buses in Hong Kong.

PubMed

Shek, Ka Wing; Chan, Wai Tin

2008-01-25

Air-conditioning settings are important factors in controlling the comfort of passengers on buses. The local bus operators control in-bus air quality and thermal environment by conforming to the prescribed levels stated in published standards. As a result, the settings are merely adjusted to fulfill the standards, rather than to satisfy the passengers' thermal comfort and air quality. Such "standard-oriented" practices are not appropriate; the passengers' preferences and satisfaction should be emphasized instead. Thus a "comfort-oriented" philosophy should be implemented to achieve a comfortable in-bus commuting environment. In this study, the achievement of a comfortable in-bus environment was examined with emphasis on thermal comfort and air quality. Both the measurement of physical parameters and subjective questionnaire surveys were conducted to collect practical in-bus thermal and air parameters data, as well as subjective satisfaction and sensation votes from the passengers. By analyzing the correlation between the objective and subjective data, a combined comfort models were developed. The models helped in evaluating the percentage of dissatisfaction under various combinations of passengers' sensation votes towards thermal comfort and air quality. An effective approach integrated the combined comfort model, hardware and software systems and the bus air-conditioning system could effectively control the transient in-bus environment. By processing and analyzing the data from the continuous monitoring system with the combined comfort model, air-conditioning setting adjustment commands could be determined and delivered to the hardware. This system adjusted air-conditioning settings depending on real-time commands along the bus journey. Therefore, a comfortable in-bus air quality and thermal environment could be achieved and efficiently maintained along the bus journey despite dynamic outdoor influences. Moreover, this model can help optimize air-conditioning control by striking a beneficial balance between energy conservation and passengers' satisfaction level.

Health Effects of Air Pollution: A Historical Review and Present Status.

PubMed

Shima, Masayuki

2017-01-01

During the 1960s, the concentrations of air pollutants, particularly that of sulfur dioxide (SO 2 ), were extremely high in many industrial cities in Japan, and the prevalence of bronchial asthma and chronic bronchitis increased among residents living in the cities. To evaluate the effects of air pollution on respiratory diseases, many epidemiological studies were conducted, and the findings played an important role in the regulatory control of air pollution. After 1970, the concentration of SO 2 has decreased markedly, and its adverse health effects have been minimized. On the other hand, the increasing automobile traffic in Japan has caused considerable increases in concentrations of air pollutants, such as nitrogen oxides (NOx) and particulate matter (PM). The large-scale epidemiological studies conducted in Japan showed that traffic-related air pollution was associated with the development of asthma in school children and the persistence of asthmatic symptoms in preschool children. In recent years, however, the concentrations of NOx and PM have gradually decreased, since control measures based on the Automobile NOx/PM law were enforced in 2001. At present, the adverse health effects of airborne fine particulate matter (PM 2.5 ) and photochemical oxidants have become a major concern. These air pollutants consist of not only emissions from primary sources but also secondary formations in air, and have spread worldwide. Both short- and long-term exposure to these air pollutants are reported to increase the risk of respiratory and cardiovascular diseases in the population. Therefore, global efforts are necessary to reduce the health risk of these air pollutants.

Controlling Indoor Air Pollution from Moxibustion

PubMed Central

Lu, Chung-Yen; Kang, Sy-Yuan; Liu, Shu-Hui; Mai, Cheng-Wei; Tseng, Chao-Heng

2016-01-01

Indoor air quality (IAQ) control of hospitals plays a critical role in protecting both hospital staffs and patients, particularly those who are highly susceptible to the adverse effects of indoor noxious hazards. However, moxibustion in outpatient departments (OPDs) of traditional Chinese medicine (TCM) may be a source of indoor air pollution in hospitals. Some studies have investigated indoor air pollution during moxibustion in Chinese medicine clinics (CMCs) and moxibustion rooms, demonstrating elevated air pollutants that pose a threat to the health of medical staff and patients. Our study investigated the indoor air pollutants of indoor carbon dioxide (CO2), carbon monoxide (CO), formaldehyde (HCHO), total volatile organic compounds (TVOCs), airborne particulate matter with a diameter of ≤10 µm (PM10) and ≤2.5 µm (PM2.5) during moxibustion in an acupuncture and moxibustion room of the OPD in a hospital in Taipei. To evaluate the different control strategies for indoor air pollution from moxibution, a comparison of air pollutants during moxibution among the methods of using alternative old moxa wools, local exhaust ventilation and an air cleaner was conducted. In this study, burning alternative old moxa wools for moxibustion obviously reduced all gaseous pollutants except for aerosols comparing burning fresh moxa wools. Using local exhaust ventilation reduced most of the aerosols after burning moxa. We also found that using an air cleaner was inefficient for controlling indoor air pollutants, particularly gaseous pollutants. Therefore, combining replacing alternative old moxa wools and local exhaust ventilation could be a suitable design for controlling indoor air pollution during moxibustion therapy. PMID:27331817

Controlling Indoor Air Pollution from Moxibustion.

PubMed

Lu, Chung-Yen; Kang, Sy-Yuan; Liu, Shu-Hui; Mai, Cheng-Wei; Tseng, Chao-Heng

2016-06-20

Indoor air quality (IAQ) control of hospitals plays a critical role in protecting both hospital staffs and patients, particularly those who are highly susceptible to the adverse effects of indoor noxious hazards. However, moxibustion in outpatient departments (OPDs) of traditional Chinese medicine (TCM) may be a source of indoor air pollution in hospitals. Some studies have investigated indoor air pollution during moxibustion in Chinese medicine clinics (CMCs) and moxibustion rooms, demonstrating elevated air pollutants that pose a threat to the health of medical staff and patients. Our study investigated the indoor air pollutants of indoor carbon dioxide (CO₂), carbon monoxide (CO), formaldehyde (HCHO), total volatile organic compounds (TVOCs), airborne particulate matter with a diameter of ≤10 µm (PM10) and ≤2.5 µm (PM2.5) during moxibustion in an acupuncture and moxibustion room of the OPD in a hospital in Taipei. To evaluate the different control strategies for indoor air pollution from moxibution, a comparison of air pollutants during moxibution among the methods of using alternative old moxa wools, local exhaust ventilation and an air cleaner was conducted. In this study, burning alternative old moxa wools for moxibustion obviously reduced all gaseous pollutants except for aerosols comparing burning fresh moxa wools. Using local exhaust ventilation reduced most of the aerosols after burning moxa. We also found that using an air cleaner was inefficient for controlling indoor air pollutants, particularly gaseous pollutants. Therefore, combining replacing alternative old moxa wools and local exhaust ventilation could be a suitable design for controlling indoor air pollution during moxibustion therapy.

The effects of RF plasma ashing on zinc orthotitanate/potassium silicate thermal control coatings

NASA Technical Reports Server (NTRS)

Dever, Joyce A.; Bruckner, Eric J.

1992-01-01

Samples of YB-71, a white thermal control coating composed of zinc orthotitanate pigment in a potassium silicate binder, were exposed in air plasma and in oxygen plasma to determine optical property and surface chemistry changes. Results show that YB-71 undergoes a significant reflectance decrease upon exposure to the simulated LEO atomic oxygen environment provided by an air plasma asher. YB-71 samples exposed to the same effective fluence in oxygen plasma, or in a UV screening Faraday cage in air or oxygen, do not undergo as severe reflectance decreases as the samples exposed in the air plasma asher environment. The UV and VUV radiation present in the plasma ashers affects the YB-71 degradation. It is noted that, when using plasma ashers to determine LEO degradation, it is necessary to take into account the sensitivity of the material to the synergistic effects of atomic oxygen and accelerated UV radiation.

UAS in the NAS Air Traffic Controller Acceptability Study-1: The Effects of Horizontal Miss Distances on Simulated UAS and Manned Aircraft Encounters

NASA Technical Reports Server (NTRS)

Ghatas, Rania W.; Comstock, James R., Jr.; Consiglio, Maria C.; Chamberlain, James P.; Hoffler, Keith D.

2015-01-01

This study examined air traffic controller acceptability ratings based on the effects of differing horizontal miss distances (HMDs) for encounters between UAS and manned aircraft. In a simulation of the Dallas/Fort Worth (DFW) East-side airspace, the CAS-1 experiment at NASA Langley Research Center enlisted fourteen recently retired DFW air traffic controllers to rate well-clear volumes based on differing HMDs that ranged from 0.5 NM to 3.0 NM. The controllers were tasked with rating these HMDs from "too small" to "too excessive" on a defined, 1-5, scale and whether these distances caused any disruptions to the controller and/or to the surrounding traffic flow. Results of the study indicated a clear favoring towards a particular HMD range. Controller workload was also measured. Data from this experiment and subsequent experiments will play a crucial role in the FAA's establishment of rules, regulations, and procedures to safely and efficiently integrate UAS into the NAS.

Developing regulatory programs for the control of acid precipitation

Treesearch

Michael A. Berry; John D. Bachmann

1976-01-01

The U.S. Clean Air Act provides mechanisms by which the public welfare may be protected from "any known or anticipated adverse effects associated with the presence of (an) air pollutant in the ambient air." The history of the U.S. Environment Protection Agency's (EPA) efforts to establish and defend a secondary ambient air quality standard for sulfur...

El Nino impacts on seasonal high ozone levels in the lower troposphere

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

Linse, E.W. Jr.

The purpose of this paper is to clarify one difficulty in evaluating the control strategies for ozone concentrations. El Nino years may be mistakenly interpreted as periods having improved air quality because of those control programs. In fact, the differences in atmospheric stability and mixing have made some years especially benign for air quality. Improvements or the effectiveness of control programs can only be effectively reviewed if the meteorological signature is removed. It may not be generally known how large the impacts of the El Nino conditions can be.

Active control of helicopter air resonance in hover and forward flight

NASA Technical Reports Server (NTRS)

Takahashi, M. D.; Friedman, P. P.

1988-01-01

A coupled rotor/fuselage helicopter analysis is presented. The accuracy of the model is illustrated by comparing it with experimental data. The sensitivity of the open loop damping of the unstable resonance mode to such modeling effects as blade torsional flexibility, unsteady aerodynamics, forward flight, periodic terms, and trim solution is illustrated by numerous examples. Subsequently, the model is used in conjunction with linear optimal control theory to stabilize the air resonance mode. The influence of the modeling effects mentioned before on active resonance control is then investigated.

Fabrication of Simple Indoor Air Haze Purifier using Domestic Discarded Substances and Its Haze Removal Performance

NASA Astrophysics Data System (ADS)

Wang, Zhou; Cao, Haoshu; Zhao, Shuang

2018-01-01

Based on the concept of circular economy, discarded plastic bottles stuffed with discarded cotton, clothing and sofa cushion were used as pre-filter to remove big particles (dust and coal dust) in air and 4 L tap water in discarded plastic bottle was worked as an absorbing medium to dissolve the water soluble ions in air (SO4 2-, NO3-, NH4+, Cl- and Ca2+). Moreover, the internet control design was used in this homemade indoor air haze purifier to achieve the performance of remote control and intelligent management. The experimental results showed that this indoor air haze purifier can effectively reduce the level of indoor air haze and the air quality after 20 minutes treatment is higher than that of two commercial well-known air haze purifier

Odors and Air Pollution: A Bibliography with Abstracts.

ERIC Educational Resources Information Center

Environmental Protection Agency, Research Triangle Park, NC. Office of Air Programs.

The annotated bibliography presents a compilation of abstracts which deal with odors as they relate to air pollution. The abstracts are arranged within the following categories: Emission sources; Control methods; Measurement methods; Air quality measurements; Atmospheric interaction; Basic science and technology; Effects-human health;…

Efficient control of air pollution through plants, a cost-effective alternative: studies on Dalbergia sissoo Roxb.

PubMed

Kapoor, C S; Bamniya, B R; Kapoor, K

2013-09-01

Plants can be used as both passive biomonitors and biomitigators in urban and industrial environments to indicate the environmental quality and to ameliorate pollution level in a locality. Many studies reveal that plants are negatively affected by the ambient levels of air pollutants. The present study was conducted to evaluate the impact of air pollution on comparative basis with reference to changes in photosynthetic pigments, plant height, leaves, as well as, biochemical parameters of plants of different sites around Udaipur city receiving varying levels of pollution load. The investigated tree species Dalbergia sissoo Roxb. (Family: Fabaceae) exhibited a reduction in various physiological and biochemical growth parameters that correspond with air pollution levels at different sites. The tree species growing in polluted and control areas were compared with respect to foliar dust load, leaf area, and chlorophyll and total carbohydrate and total protein concentration in the leaves. Our studies suggest that D. sissoo Roxb. can successfully be grown in an area for monitoring air pollution, where it is mild and droughts are common. It will prove as an ideal tree species to control pollution effectively beside acting as a shade tree and being a source of food for birds and animals. By plantation of D. sissoo Roxb., mitigative measure at the polluted sites to control generation of particulate matter and the air quality required can be ensured. Our results also confirm that industrial and vehicular air pollution level in Udaipur city is shifting beyond limits.

Tuberculosis Infection Control in Health-Care Facilities: Environmental Control and Personal Protection.

PubMed

Lee, Ji Yeon

2016-10-01

Transmission of tuberculosis (TB) is a recognized risk to patients and healthcare workers in healthcare settings. The literature review suggests that implementation of combination control measures reduces the risk of TB transmission. Guidelines suggest a three-level hierarchy of controls including administrative, environmental, and respiratory protection. Among environmental controls, installation of ventilation systems is a priority because ventilation reduces the number of infectious particles in the air. Natural ventilation is cost-effective but depends on climatic conditions. Supplemented intervention such as air-cleaning methods including high efficiency particulate air filtration and ultraviolet germicidal irradiation should be considered in areas where adequate ventilation is difficult to achieve. Personal protective equipment including particulate respirators provides additional benefit when administrative and environmental controls cannot assure protection.

Integrated Air and Missile Defense (IAMD)

DTIC Science & Technology

2015-12-01

equal to or greater than the effectiveness levels of fielded TBM and CM/ABT defense systems. Common Command and Control The Army IAMD SoS common C2...externally developed sensors and shooters to provide an effective IAMD capability. The IAMD program will allow transformation to a network-centric system of...systems capability, also referred to as "Plug and Fight", that integrates all Air and Missile Defense (AMD) sensors, weapons, and mission control

Overview of air biofiltration - basic technology, economics and integration with other control technologies for effective treatment of air toxics

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

Govind, R.; Bishop, D.F.

1996-12-31

This paper provides an overview of air biofiltration with experimental data on the performance of peat/compost, pelletized packed bed and structured media biofilters. It is shown that use of high surface area per unit volume structured media results in higher contaminant treatment rates per unit biofilter volume. Peat/compost biofilters exhibit lower removal efficiencies at high (> 100 ppmv) inlet contaminant concentrations and require control of media moisture content. Increase of temperature results in increasing biodegradation rates. It is shown that use of structured ceramic media allows effective control of biomass buildup by continuous removal of biomass from the biofilter mediamore » and that the biomass removal rate depends on nutrient flowrate. An experimental system is presented which enables biofilm kinetics to be determined and a simple biofilter model is developed in this paper. A group contribution approach has been developed to estimate biokinetic parameter which allows biofiltration effectiveness to be determined for a variety of volatile organic compounds (VOCs). Finally, a procedure is presented, illustrated by an example, which is used to develop an integrated process for effective treatment of air contaminants. 22 refs., 12 figs., 4 tabs.« less

Servo-control for maintaining abdominal skin temperature at 36C in low birth weight infants.

PubMed

Sinclair, J C

2002-01-01

Randomized trials have shown that the neonatal mortality rate of low birth-weight babies can be reduced by keeping them warm. For low birth-weight babies nursed in incubators, warm conditions may be achieved either by heating the air to a desired temperature, or by servo-controlling the baby's body temperature at a desired set-point. In low birth weight infants, to determine the effect on death and other important clinical outcomes of targeting body temperature rather than air temperature as the end-point of control of incubator heating. Standard search strategy of the Cochrane Neonatal Review Group. Searches were made of the Cochrane Controlled Trials Register (CCTR) (Cochrane Library, Issue 4, 2001) and MEDLINE, 1966 to November 2001. Randomized or quasi-randomized trials which test the effects of having the heat output of the incubator servo-controlled from body temperature compared with setting a constant incubator air temperature. Trial methodologic quality was systematically assessed. Outcome measures included death, timing of death, cause of death, and other clinical outcomes. Categorical outcomes were analyzed using relative risk and risk difference. Meta-analysis assumed a fixed effect model. Two eligible trials were found. In total, they included 283 babies and 112 deaths. Compared to setting a constant incubator air temperature of 31.8C, servo-control of abdominal skin temperature at 36C reduces the neonatal death rate among low birth weight infants: relative risk 0.72 (95% CI 0.54, 0.97); risk difference -12.7% (95% CI -1.6, -23.9). This effect is even greater among VLBW infants. During at least the first week after birth, low birth weight babies should be provided with a carefully regulated thermal environment that is near the thermoneutral point. For LBW babies in incubators, this can be achieved by adjusting incubator temperature to maintain an anterior abdominal skin temperature of at least 36C, using either servo-control or frequent manual adjustment of incubator air temperature.

Will the circle be unbroken: a history of the U.S. National Ambient Air Quality Standards.

PubMed

Bachmann, John

2007-06-01

In celebration of the 100th anniversary of the Air & Waste Management Association, this review examines the history of air quality management (AQM) in the United States over the last century, with an emphasis on the ambient standards programs established by the landmark 1970 Clean Air Act (CAA) Amendments. The current CAA system is a hybrid of several distinct air pollution control philosophies, including the recursive or circular system driven by ambient standards. Although this evolving system has resulted in tremendous improvements in air quality, it has been far from perfect in terms of timeliness and effectiveness. The paper looks at several periods in the history of the U.S. program, including: (1) 1900-1970, spanning the early smoke abatement and smog control programs, the first federal involvement, and the development of a hybrid AQM approach in the 1970 CAA; (2) 1971-1976, when the first National Ambient Air Quality Standards (NAAQS) were set and implemented; (3) 1977-1993, a period of the first revisions to the standards, new CAA Amendments, delays in implementation and decision-making, and key science/policy/legislative developments that would alter both the focus and scale of air pollution programs and how they are implemented; and (4) 1993-2006, the second and third wave of NAAQS revisions and their implementation in the context of the 1990 CAA. This discussion examines where NAAQS have helped drive implementation programs and how improvements in both effects and air quality/control sciences influenced policy and legislation to enhance the effectiveness of the system over time. The review concludes with a look toward the future of AQM, emphasizing challenges and ways to meet them. The most significant of these is the need to make more efficient progress toward air quality goals, while adjusting the system to address the growing intersections between air quality management and climate change.

A PRELIMINARY METHODOLOGY FOR EVALUATING THE COST-EFFECTIVENESS OF ALTERNATIVE INDOOR AIR QUALITY APPROACHES

EPA Science Inventory

The report defines a simplified methodology that can be used by indoor air quality (IAQ) diagnosticians, architects/engineers, building owners/operators, and the scientific community for preliminary comparison of the cost-effectiveness of alternative IAQ control measures for any ...

To what extent can China’s near-term air pollution control policy protect air quality and human health? A case study of the Pearl River Delta region

NASA Astrophysics Data System (ADS)

Jiang, Xujia; Hong, Chaopeng; Zheng, Yixuan; Zheng, Bo; Guan, Dabo; Gouldson, Andy; Zhang, Qiang; He, Kebin

2015-10-01

Following a series of extreme air pollution events, the Chinese government released the Air Pollution Prevention and Control Action Plan in 2013 (China’s State Council 2013). The Action Plan sets clear goals for key regions (i.e. cities above the prefecture level, Beijing-Tianjin-Hebei Province, the Yangtze River Delta and the Pearl River Delta) and establishes near-term control efforts for the next five years. However, the extent to which the Action Plan can direct local governments’ activities on air pollution control remains unknown. Here we seek to evaluate the air quality improvement and associated health benefits achievable under the Action Plan in the Pearl River Delta (PRD) area from 2012 to 2017. Measure-by-measure quantification results show that the Action Plan would promise effective emissions reductions of 34% of SO2, 28% of NOx, 26% of PM2.5 (particulate matter less than 2.5 μm in diameter), and 10% of VOCs (volatile organic compounds). These emissions abatements would lower the PM2.5 concentration by 17%, surpassing the 15% target established in the Action Plan, thereby avoiding more than 2900 deaths and 4300 hospital admissions annually. We expect the implementation of the Action Plan in the PRD would be productive; the anticipated impacts, however, fall short of the goal of protecting the health of local residents, as there are still more than 33 million people living in places where the annual mean ambient PM2.5 concentrations are greater than 35 μg m-3, the interim target-3 of the World Health Organization (WHO). We therefore propose the next steps for air pollution control that are important not only for the PRD but also for all other regions of China as they develop and implement effective air pollution control policies.

Effectiveness of air purifier on health outcomes and indoor particles in homes of children with allergic diseases in Fresno, California: A pilot study.

PubMed

Park, Hye-Kyung; Cheng, Kai-Chung; Tetteh, Afua O; Hildemann, Lynn M; Nadeau, Kari C

2017-05-01

Epidemiologic studies indicate that indoor air pollution is correlated with morbidity caused by allergic diseases. We evaluated the effectiveness of reducing the levels of indoor fine particulate matter <2.5 micrometer diameter (PM 2.5 ) in Fresno, California using air purifiers on health outcomes in children with asthma and/or allergic rhinitis. The active group (with air purifiers) and the control group consisted of eight houses each. Air purifiers were installed in the living rooms and bedrooms of the subjects in the active group during the entire 12-week study duration. Childhood asthma control test, peak flow rate monitoring, and nasal symptom scores were evaluated at weeks 0, 6, and 12. At 12 weeks, the active group showed a trend toward an improvement of childhood asthma control test scores and mean evening peak flow rates, whereas the control group showed deterioration in the same measures. Total and daytime nasal symptoms scores significantly reduced in the active group (p = 0.001 and p = 0.011, respectively). The average indoor PM 2.5 concentrations reduced by 43% (7.42 to 4.28 μg/m 3 ) in the active group (p = 0.001). Intervention with air purifiers reduces indoor PM 2.5 levels with significant improvements in nasal symptoms in children with allergic rhinitis in Fresno.

Comparison of performance on the Shipley Institute of Living Scale, air traffic control specialist selection test, and FAA Academy screen.

DOT National Transportation Integrated Search

1992-11-01

This study was conducted to establish norms for ATCS personnel on a group test of intellectual functioning, the Shipley Institute of Living Scale (SILS), to screen subjects for future research on the effects of Air Traffic Control Specialist (ATCS) r...

Some effects of 8- vs 10-hour work schedules on the test performance/alertness of air traffic control specialists.

DOT National Transportation Integrated Search

1995-12-01

A 10-hour, 4-day rotating shift schedule worked by some Air Traffic Control Specialists (ATCSs) was compared to the more traditional 8-hour, 2-2-1 rapidly rotating schedule. Measures of performance and alertness were obtained from a group of 52 ATCSs...

Investigation of air transportation technology at Princeton University, 1986

NASA Technical Reports Server (NTRS)

Stengel, Robert F.

1988-01-01

The Air Transportation Technology Program at Princeton proceeded along four avenues: Guidance and control strategies for penetration of microbursts and wind shear; Application of artificial intelligence in flight control systems; Computer aided control system design; and Effects of control saturation on closed loop stability and response of open loop unstable aircraft. Areas of investigation relate to guidance and control of commercial transports as well as general aviation aircraft. Interaction between the flight crew and automatic systems is a subject of prime concern.

Octafluoropropane Concentration Dynamics on Board the International Space Station

NASA Technical Reports Server (NTRS)

Perry, J. L.

2003-01-01

Since activating the International Space Station s (IS9 Service Module in November 2000, archival air quality samples have shown highly variable concentrations of octafluoropropane in the cabin. This variability has been directly linked to leakage from air conditioning systems on board the Service Module, Zvezda. While octafluoro- propane is not highly toxic, it presents a significant chal- lenge to the trace contaminant control systems. A discussion of octafluoropropane concentration dynamics is presented and the ability of on board trace contami- nant control systems to effectively remove octafluoropro- pane from the cabin atmosphere is assessed. Consideration is given to operational and logistics issues that may arise from octafluoropropane and other halo- carbon challenges to the contamination control systems as well as the potential for effecting cabin air quality.

JT9D-70/59 Improved High Pressure Turbine Active Clearance Control System. [for specific fuel consumption improvement

NASA Technical Reports Server (NTRS)

Gaffin, W. O.

1979-01-01

The JT9D-70/59 high pressure turbine active clearance control system was modified to provide reduction of blade tip clearance when the system is activated during cruise operation. The modification increased the flow capacity and air impingement effectiveness of the cooling air manifold to augment turbine case shrinkage capability, and increased responsiveness of the airseal clearance to case shrinkage. The simulated altitude engine testing indicated a significant improvement in specific fuel consumption with the modified system. A 1000 cycle engine endurance test showed no unusual wear or performance deterioration effects on the engine or the clearance control system. Rig tests indicated that the air impingement and seal support configurations used in the engine tests are near optimum.

Air Pollution Translations: A Bibliography with Abstracts - Volume 4.

ERIC Educational Resources Information Center

Environmental Protection Agency, Research Triangle Park, NC. Air Pollution Technical Information Center.

This volume is the fourth in a series of compilations presenting abstracts and indexes of translations of technical air pollution literature. The entries are grouped into 12 subject categories: Emission Sources, Control Methods, Measurement Methods, Air Quality Measurements, Atmospheric Interaction, Basic Science and Technology, Effects--Human…

Malondialdehyde-Deoxyguanosine Adduct Formation in Workers of Pathology Wards. The Role of Air Formaldehyde Exposure

PubMed Central

Romanazzi, Valeria; Munnia, Armelle; Piro, Sara; Allione, Alessandra; Ricceri, Fulvio; Guarrera, Simonetta; Pignata, Cristina; Matullo, Giuseppe; Wang, Poguang; Giese, Roger W.; Peluso, Marco

2010-01-01

Background Formaldehyde is a ubiquitous pollutant to which humans are exposed. Pathologists can experience high formaldehyde exposure levels. Formaldehyde – among other properties – induce oxidative stress and free radicals, which react with DNA and lipids, leading to oxidative damage and lipid peroxidation, respectively. We measured the levels of air-formaldehyde exposure in a group of Italian pathologists and controls. We analyzed the effect of formaldehyde exposure on leukocyte malondialdehyde-deoxyguanosine adducts (M1-dG), a biomarker of oxidative stress and lipid peroxidation. We studied the relationship between air-formaldehyde and M1-dG adducts. Methods Air-formaldehyde levels were measured by personal air samplers. M1-dG adducts were analyzed by 32P-postlabelling assay. Results Reduction rooms pathologists were significantly exposed to air-formaldehyde in respect to controls and to the pathologists working in other laboratory areas (p<0.001). A significant difference for M1-dG adducts between exposed pathologists and controls was found (p=0.045). The effect becomes stronger when the evaluation of air-formaldehyde exposure was based on personal samplers (p=0.018). Increased M1dG adduct levels were only found in individuals exposed to air-formaldehyde concentrations higher than 66 μg/m3. When the exposed workers and controls were subgrouped according to smoking, M1-dG tended to increase in all the subjects but a significant association between M1-dG and air-formaldehyde was only found in not smokers (p= 0.009). Air formaldehyde played a role positive but not significant (r = 0.355, p = 0.075, Pearson correlation) in the formation of M1-dG, only in not smokers. Conclusions Working in the reduction rooms and to be exposed to air-formaldehyde concentrations higher than 66 μg/m3 is associated with increased levels of M1-dG adducts. PMID:20707408

Air Pollution Prevention and Control Policy in China.

PubMed

Huang, Cunrui; Wang, Qiong; Wang, Suhan; Ren, Meng; Ma, Rui; He, Yiling

2017-01-01

With rapid urbanization and development of transport infrastructure, air pollution caused by multiple-pollutant emissions and vehicle exhaust has been aggravated year by year in China. In order to improve air quality, the Chinese authorities have taken a series of actions to control air pollution emission load within a permissible range. However, although China has made positive progress on tackling air pollution, these actions have not kept up with its economy growth and fossil-fuel use. The traditional single-pollutant approach is far from enough in China now, and in the near future, air pollution control strategies should move in the direction of the multiple-pollutant approach. In addition, undesirable air quality is usually linked with the combination of high emissions and adverse weather conditions. However, few studies have been done on the influence of climate change on atmospheric chemistry in the global perspective. Available evidence suggested that climate change is likely to exacerbate certain kinds of air pollutants including ozone and smoke from wildfires. This has become a major public health problem because the interactions of global climate change, urban heat islands, and air pollution have adverse effects on human health. In this chapter, we first review the past and current circumstances of China's responses to air pollution. Then we discuss the control challenges and future options for a better air quality in China. Finally, we begin to unravel links between air pollution and climate change, providing new opportunities for integrated research and actions in China.

Tracking Emissions Using New Fenceline Monitoring Technology

EPA Pesticide Factsheets

New cost-effective approaches to measuring air pollutants at the fenceline or in communities near industrial facilities can help identify and control air pollution that may drift across property lines.

Use of antimicrobial biodegradable packaging to control Listeria monocytogenes during storage of cooked ham.

PubMed

Marcos, Begonya; Aymerich, Teresa; Monfort, Josep M; Garriga, Margarita

2007-11-30

The antimicrobial effect against L. monocytogenes of biodegradable films (alginate, zein and polyvinyl alcohol) containing enterocins was investigated. Survival of the pathogen was studied by means of challenge tests performed at 6 degrees C during 8 and 29 days, for air-packed and vacuum-packed sliced cooked ham, respectively. Air packaging was tested with two concentrations of enterocins (200 and 2000 AU/cm2). Control air-packed cooked ham showed an increase of L. monocytogenes from 10(4) to 10(7) CFU/g after 8 days. By contrast, packaging with antimicrobial films effectively slowed down the pathogen's growth, leading to final counts lower than in control lots. Air-packaging with alginate films containing 2000 AU/cm2 of enterocins effectively controlled L. monocytogenes for 8 days. An increase of only 1 log unit was observed in zein and polyvinyl alcohol lots at the same enterocin concentration. Vacuum packaging with films containing enterocins (2000 AU/cm2) also delayed the growth of the pathogen. No increase from inoculated levels was observed during 15 days in antimicrobial alginate films. After 29 days of storage, the lowest counts were obtained in samples packed with zein and alginate films containing enterocins, as well as with zein control films. The most effective treatment for controlling L. monocytogenes during 6 degrees C storage was vacuum-packaging of sliced cooked ham with alginate films containing 2000 AU/cm2 of enterocins. From the results obtained it can concluded that antimicrobial packaging can improve the safety of sliced cooked ham by delaying and reducing the growth of L. monocytogenes.

[Thermal energy utilization analysis and energy conservation measures of fluidized bed dryer].

PubMed

Xing, Liming; Zhao, Zhengsheng

2012-07-01

To propose measures for enhancing thermal energy utilization by analyzing drying process and operation principle of fluidized bed dryers,in order to guide optimization and upgrade of fluidized bed drying equipment. Through a systematic analysis on drying process and operation principle of fluidized beds,the energy conservation law was adopted to calculate thermal energy of dryers. The thermal energy of fluidized bed dryers is mainly used to make up for thermal consumption of water evaporation (Qw), hot air from outlet equipment (Qe), thermal consumption for heating and drying wet materials (Qm) and heat dissipation to surroundings through hot air pipelines and cyclone separators. Effective measures and major approaches to enhance thermal energy utilization of fluidized bed dryers were to reduce exhaust gas out by the loss of heat Qe, recycle dryer export air quantity of heat, preserve heat for dry towers, hot air pipes and cyclone separators, dehumidify clean air in inlets and reasonably control drying time and air temperature. Such technical parameters such air supply rate, air inlet temperature and humidity, material temperature and outlet temperature and humidity are set and controlled to effectively save energy during the drying process and reduce the production cost.

Air Ground Integration Study

NASA Technical Reports Server (NTRS)

Lozito, Sandy; Mackintosh, Margaret-Anne; DiMeo, Karen; Kopardekar, Parimal

2002-01-01

A simulation was conducted to examine the effect of shared air/ground authority when each is equipped with enhanced traffic- and conflict-alerting systems. The potential benefits of an advanced air traffic management (ATM) concept referred to as "free flight" include improved safety through enhanced conflict detection and resolution capabilities, increased flight-operations management, and better decision-making tools for air traffic controllers and flight crews. One element of the free-flight concept suggests shifting aircraft separation responsibility from air traffic controllers to flight crews, thereby creating an environment with "shared-separation" authority. During FY00. NASA, the Federal Aviation Administration (FAA), and the Volpe National Transportation Systems Center completed the first integrated, high-fidelity, real-time, human-in-the-loop simulation.

Installation of a flow control device in an inclined air-curtain fume hood to control wake-induced exposure.

PubMed

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.

Transparent air filter for high-efficiency PM2.5 capture.

PubMed

Liu, Chong; Hsu, Po-Chun; Lee, Hyun-Wook; Ye, Meng; Zheng, Guangyuan; Liu, Nian; Li, Weiyang; Cui, Yi

2015-02-16

Particulate matter (PM) pollution has raised serious concerns for public health. Although outdoor individual protection could be achieved by facial masks, indoor air usually relies on expensive and energy-intensive air-filtering devices. Here, we introduce a transparent air filter for indoor air protection through windows that uses natural passive ventilation to effectively protect the indoor air quality. By controlling the surface chemistry to enable strong PM adhesion and also the microstructure of the air filters to increase the capture possibilities, we achieve transparent, high air flow and highly effective air filters of ~90% transparency with >95.00% removal of PM2.5 under extreme hazardous air-quality conditions (PM2.5 mass concentration >250 μg m(-3)). A field test in Beijing shows that the polyacrylonitrile transparent air filter has the best PM2.5 removal efficiency of 98.69% at high transmittance of ~77% during haze occurrence.

Transparent air filter for high-efficiency PM2.5 capture

NASA Astrophysics Data System (ADS)

Liu, Chong; Hsu, Po-Chun; Lee, Hyun-Wook; Ye, Meng; Zheng, Guangyuan; Liu, Nian; Li, Weiyang; Cui, Yi

2015-02-01

Particulate matter (PM) pollution has raised serious concerns for public health. Although outdoor individual protection could be achieved by facial masks, indoor air usually relies on expensive and energy-intensive air-filtering devices. Here, we introduce a transparent air filter for indoor air protection through windows that uses natural passive ventilation to effectively protect the indoor air quality. By controlling the surface chemistry to enable strong PM adhesion and also the microstructure of the air filters to increase the capture possibilities, we achieve transparent, high air flow and highly effective air filters of ~90% transparency with >95.00% removal of PM2.5 under extreme hazardous air-quality conditions (PM2.5 mass concentration >250 μg m-3). A field test in Beijing shows that the polyacrylonitrile transparent air filter has the best PM2.5 removal efficiency of 98.69% at high transmittance of ~77% during haze occurrence.

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

PubMed

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

2011-01-01

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

Integration of Fire Control, Flight Control and Propulsion Control Systems.

DTIC Science & Technology

1983-08-01

process of preparation to a degree imocmpatible with fast moving technology. Undoubtedly something can be done to see that US authors produce papers...PDU provide a true "Up Front" system controller. Fast selection of Air to Air Mode is provided by 2 pushbuttons on the throttle. Pushing one or both...nature of the load snd its effect on the generation system. This calculation will include Load Power, Reactance, Nature - continuous or intermittent

The 14th Annual Conference on Manual Control. [digital simulation of human operator dynamics

NASA Technical Reports Server (NTRS)

1978-01-01

Human operator dynamics during actual manual control or while monitoring the automatic control systems involved in air-to-air tracking, automobile driving, the operator of undersea vehicles, and remote handling are examined. Optimal control models and the use of mathematical theory in representing man behavior in complex man machine system tasks are discussed with emphasis on eye/head tracking and scanning; perception and attention allocation; decision making; and motion simulation and effects.

Comparative study between cold air analgesia and supraorbital and supratrochlear nerve block for the management of pain during photodynamic therapy for actinic keratoses of the frontotemporal zone.

PubMed

Serra-Guillen, C; Hueso, L; Nagore, E; Vila, M; Llombart, B; Requena Caballero, C; Botella-Estrada, R; Sanmartin, O; Alfaro-Rubio, A; Guillen, C

2009-08-01

Photodynamic therapy (PDT) is an effective treatment for actinic keratoses, Bowen's disease and basal cell carcinoma. The main drawback of PDT is pain during application. To compare the efficacy of supratrochlear and supraorbital nerve block with cold air analgesia to control the pain experienced during PDT. A controlled open clinical trial was conducted in 34 patients having multiple actinic keratoses in the frontal region treated with PDT. On one side of the frontal region the supratrochlear and supraorbital nerves were blocked, while on the other side cold air was used as the method of analgesia. Pain was recorded on a visual analogue scale after treatment. Thirty-one of 34 patients reported less pain in the zone treated with nerve block. This difference was statistically significant. Nerve block is superior to cold air and is an easy, safe, effective means of controlling the pain associated with PDT.

Linear kinematic air bearing

NASA Technical Reports Server (NTRS)

Mayall, S. D.

1974-01-01

Bearing provides continuous, smooth movement of the cat's-eye mirror, eliminating wear and deterioration of bearing surface and resulting oscillation effects in servo system. Design features self-aligning configuration; single-point, pivotal pad mounting, having air passage through it; and design of pads that allows for precise control of discharge path of air from pads.

Co-control of urban air pollutants and greenhouse gases in Mexico City.

PubMed

West, J Jason; Osnaya, Patricia; Laguna, Israel; Martínez, Julia; Fernández, Adrián

2004-07-01

This study addresses the synergies of mitigation measures to control urban air pollutant and greenhouse gas (GHG) emissions, in developing integrated "co-control" strategies for Mexico City. First, existing studies of emissions reduction measures--PROAIRE (the air quality plan for Mexico City) and separate GHG studies--are used to construct a harmonized database of options. Second, linear programming (LP) is developed and applied as a decision-support tool to analyze least-cost strategies for meeting co-control targets for multiple pollutants. We estimate that implementing PROAIRE measures as planned will reduce 3.1% of the 2010 metropolitan CO2 emissions, in addition to substantial local air pollutant reductions. Applying the LP, PROAIRE emissions reductions can be met at a 20% lower cost, using only the PROAIRE measures, by adjusting investments toward the more cost-effective measures; lower net costs are possible by including cost-saving GHG mitigation measures, but with increased investment. When CO2 emission reduction targets are added to PROAIRE targets, the most cost-effective solutions use PROAIRE measures for the majority of local pollutant reductions, and GHG measures for additional CO2 control. Because of synergies, the integrated planning of urban-global co-control can be beneficial, but we estimate that for Mexico City these benefits are often small.

The introduction of local air quality management in the United Kingdom: A review and theoretical framework

NASA Astrophysics Data System (ADS)

Longhurst, J. W. S.; Lindley, S. J.; Watson, A. F. R.; Conlan, D. E.

In the light of recent episodes of poor air quality in many of the U.K.'s major urban areas, concern has been expressed regarding the apparent inability of existing air quality control procedures to effectively tackle contemporary scenarios. As a result of this, a new philosophy for air quality control has been sought which can provide a solid basis for the preservation and future improvement of air quality. It is proposed that a suitable mechanism for this would be found through the adoption of an integrated and holistic local air quality management approach. This paper will present and discuss a theoretical framework for the application of local air quality management in the U.K. and investigate the potential of the Environment Act (1995) to provide such a framework.

A piloted simulation of helicopter air combat to investigate effects of variations in selected performance and control response characteristics

NASA Technical Reports Server (NTRS)

Lewis, Michael S.; Mansur, M. Hossein; Chen, Robert T. N.

1987-01-01

A piloted simulation study investigating handling qualities and flight characteristics required for helicopter air to air combat is presented. The Helicopter Air Combat system was used to investigate this role for Army rotorcraft. Experimental variables were the maneuver envelope size (load factor and sideslip), directional axis handling qualities, and pitch and roll control-response type. Over 450 simulated, low altitude, one-on-one engagements were conducted. Results from the experiment indicate that a well damped directional response, low sideforce caused by sideslip, and some effective dihedral are all desirable for weapon system performance, good handling qualities, and low pilot workload. An angular rate command system was favored over the attitude type pitch and roll response for most applications, and an enhanced maneuver envelope size over that of current generation aircraft was found to be advantageous. Pilot technique, background, and experience are additional factors which had a significant effect on performance in the air combat tasks investigated. The implication of these results on design requirements for future helicopters is presented.

Development of risk-based air quality management strategies under impacts of climate change.

PubMed

Liao, Kuo-Jen; Amar, Praveen; Tagaris, Efthimios; Russell, Armistead G

2012-05-01

Climate change is forecast to adversely affect air quality through perturbations in meteorological conditions, photochemical reactions, and precursor emissions. To protect the environment and human health from air pollution, there is an increasing recognition of the necessity of developing effective air quality management strategies under the impacts of climate change. This paper presents a framework for developing risk-based air quality management strategies that can help policy makers improve their decision-making processes in response to current and future climate change about 30-50 years from now. Development of air quality management strategies under the impacts of climate change is fundamentally a risk assessment and risk management process involving four steps: (1) assessment of the impacts of climate change and associated uncertainties; (2) determination of air quality targets; (3) selections of potential air quality management options; and (4) identification of preferred air quality management strategies that minimize control costs, maximize benefits, or limit the adverse effects of climate change on air quality when considering the scarcity of resources. The main challenge relates to the level of uncertainties associated with climate change forecasts and advancements in future control measures, since they will significantly affect the risk assessment results and development of effective air quality management plans. The concept presented in this paper can help decision makers make appropriate responses to climate change, since it provides an integrated approach for climate risk assessment and management when developing air quality management strategies. Development of climate-responsive air quality management strategies is fundamentally a risk assessment and risk management process. The risk assessment process includes quantification of climate change impacts on air quality and associated uncertainties. Risk management for air quality under the impacts of climate change includes determination of air quality targets, selections of potential management options, and identification of effective air quality management strategies through decision-making models. The risk-based decision-making framework can also be applied to develop climate-responsive management strategies for the other environmental dimensions and assess costs and benefits of future environmental management policies.

Investigation of induced recirculation during planned ventilation system maintenance

PubMed Central

Pritchard, C.J.; Scott, D.F.; Noll, J.D.; Voss, B.; Leonis, D.

2015-01-01

The Office of Mine Safety and Health Research (OMSHR) investigated ways to increase mine airflow to underground metal/nonmetal (M/NM) mine working areas to improve miners’ health and safety. One of those areas is controlled recirculation. Because the quantity of mine air often cannot be increased, reusing part of the ventilating air can be an effective alternative, if implemented properly, until the capacity of the present system is improved. The additional airflow can be used to provide effective dilution of contaminants and higher flow velocities in the underground mine environment. Most applications of controlled recirculation involve taking a portion of the return air and passing it back into the intake to increase the air volume delivered to the desired work areas. OMSHR investigated a Nevada gold mine where shaft rehabilitation was in progress and one of the two main fans was shut down to allow reduced air velocity for safe shaft work. Underground booster fan operating pressures were kept constant to maintain airflow to work areas, inducing controlled recirculation in one work zone. Investigation into system behavior and the effects of recirculation on the working area during times of reduced primary ventilation system airflow would provide additional information on implementation of controlled recirculation into the system and how these events affect M/NM ventilation systems. The National Institute for Occupational Safety and Health monitored the ventilation district when both main fans were operating and another scenario with one of the units turned off for maintenance. Airflow and contaminants were measured to determine the exposure effects of induced recirculation on miner health. Surveys showed that 19% controlled recirculation created no change in the overall district airflow distribution and a small reduction in district fresh air intake. Total dust levels increased only modestly and respirable dust levels were also low. Diesel particulate matter (DPM) levels showed a high increase in district intake mass flow, but minor increases in exposure levels related to the recirculation percentage. Utilization of DPM mass flow rates allows input into ventilation modeling programs to better understand and plan for ventilation changes and district recirculation effects on miners’ health. PMID:26190862

[Protective effect of hydrogen against hyperoxia-induced type II alveolar epithelial cell injury].

PubMed

Yao, Lan; Xu, Feng; Luo, Chong; Yu, Pan; Dong, Xinxin; Sun, Xuejun; Liu, Chengjun

2013-02-01

To investigate the protective effect of hydrogen against hyperoxia-induced oxidative stress injury in premature rat type II alveolar epithelial cells (AECs). The type II AECs isolated from premature rats were randomly divided into air (21% oxygen) control group, hyperoxia (95% oxygen) control group, air + hydrogen group, and hyperoxia+ hydrogen group. The cells with hydrogen treatment were cultured in the presence of rich hydrogen. After the corresponding exposure for 24 h, the cell morphology was observed microscopically. MTT assay was used to evaluated the cell proliferation ability, and JC-1 fluorescence probe was used to detect the mitochondrial membrane potential (δφ) changes of the type II AECs. The concentration of maleic dialdehyde (MDA) and superoxide dismutase (SOD) activity in the cell supernatant were detected using colorimetric method. No significant differences were found in cell growth or measurements between air control and air + hydrogen groups. Compared with air control group, the cells exposed to hyperoxia showed significantly suppressed proliferation, reduced mitochondrial membrane potential, increased MDA content, and decreased SOD activity. Intervention with hydrogen resulted in significantly increased cell proliferation and SOD activity and lowered MDA content, and restored the mitochondrial membrane potential in the cells with hyperoxia exposure (P<0.05). Hydrogen can significantly reduce hyperoxia-induced oxidative stress injury in premature rat type II AECs, improve the cellular antioxidant capacity, stabilize the mitochondrial membrane potential, and reduce the inhibitory effect of hyperoxia on cell proliferation.

Estimation of economic costs of particulate air pollution from road transport in China

NASA Astrophysics Data System (ADS)

Guo, X. R.; Cheng, S. Y.; Chen, D. S.; Zhou, Y.; Wang, H. Y.

2010-09-01

Valuation of health effects of air pollution is becoming a critical component of the performance of cost-benefit analysis of pollution control measures, which provides a basis for setting priorities for action. Beijing has focused on control of transport emission as vehicular emissions have recently become an important source of air pollution, particularly during Olympic games and Post-games. In this paper, we conducted an estimation of health effects and economic cost caused by road transport-related air pollution using an integrated assessment approach which utilizes air quality model, engineering, epidemiology, and economics. The results show that the total economic cost of health impacts due to air pollution contributed from transport in Beijing during 2004-2008 was 272, 297, 310, 323, 298 million US (mean value), respectively. The economic costs of road transport accounted for 0.52, 0.57, 0.60, 0.62, and 0.58% of annual Beijing GDP from 2004 to 2008. Average cost per vehicle and per ton of PM 10 emission from road transport can also be estimated as 106 US /number and 3584 US $ t -1, respectively. These findings illustrate that the impact of road transport contributed particulate air pollution on human health could be substantial in Beijing, whether in physical and economic terms. Therefore, some control measures to reduce transport emissions could lead to considerable economic benefit.

Short-term airing by natural ventilation - implication on IAQ and thermal comfort.

PubMed

Heiselberg, P; Perino, M

2010-04-01

The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. Among the available ventilation strategies that are currently available, buoyancy driven, single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and Indoor Air Quality (IAQ) control. However, to promote a wider distribution of these systems an improvement in the knowledge of their working principles is necessary. The present study analyses and presents the results of an experimental evaluation of airing performance in terms of ventilation characteristics, IAQ and thermal comfort. It includes investigations of the consequences of opening time, opening frequency, opening area and expected airflow rate, ventilation efficiency, thermal comfort and dynamic temperature conditions. A suitable laboratory test rig was developed to perform extensive experimental analyses of the phenomenon under controlled and repeatable conditions. The results showed that short-term window airing is very effective and can provide both acceptable IAQ and thermal comfort conditions in buildings. Practical Implications This study gives the necessary background and in-depth knowledge of the performance of window airing by single-sided natural ventilation necessary for the development of control strategies for window airing (length of opening period and opening frequency) for optimum IAQ and thermal comfort in naturally ventilated buildings.

Situational Leadership in Air Traffic Control

NASA Technical Reports Server (NTRS)

Arvidsson, Marcus; Johansson, Curt R.; Ek, Asa; Akselsson, Roland

2007-01-01

In high-risk environments such as air traffic control, leadership on different levels plays a certain role in establishing, promoting, and maintaining a good safety culture. The current study aimed to investigate how leadership styles, leadership style adaptability, and over and under task leadership behavior differed across situations, operative conditions, leadership structures, and working tasks in an air traffic control setting. Study locations were two air traffic control centers in Sweden with different operational conditions and leadership structures, and an administrative air traffic management unit. Leadership was measured with a questionnaire based on Leader Effectiveness and Adaptability Description (LEAD; Blanchard, Zigarmi & Zigarmi, 2003; Hersey & Blanchard, 1988). The results showed that the situation had strong impact on the leadership in which the leadership behavior was more relationship oriented in Success and Group situations than in Hardship and Individual situations. The leadership adaptability was further superior in Success and Individual situations compared with Hardship and Group situations. Operational conditions, leadership structures and working tasks were, on the other hand, not associated with leadership behavior.

Effects of an alternating work shift on air traffic controllers and the relationship with excessive daytime sleepiness and stress.

PubMed

Freitas, Ângela M; Portuguez, Mirna Wetters; Russomano, Thaís; Freitas, Marcos de; Silvello, Silvio Luis da Silva; Costa, Jaderson Costa da

2017-10-01

To evaluate symptoms of stress and excessive daytime sleepiness (EDS) in air traffic control (ATC) officers in Brazil. Fifty-two ATC officers participated, based at three air traffic control units, identified as A, B and C. Stress symptoms were assessed using the Lipp Inventory of Stress Symptoms for Adults, and EDS by the Epworth Sleepiness Scale. The sample mean age was 37 years, 76.9% of whom were male. Excessive daytime sleepiness was identified in 25% of the ATC officers, with 84.6% of these based at air traffic control unit A, which has greater air traffic flow, operating a 24-hour alternating work shift schedule. A total of 16% of the ATC officers had stress symptoms, and of these, 62% showed a predominance of physical symptoms. The high percentage of ATC officers with EDS identified in group A may be related to chronodisruption due to night work and alternating shifts.

Air Pollution Translations: A Bibliography with Abstracts - Volume 2.

ERIC Educational Resources Information Center

National Air Pollution Control Administration (DHEW), Raleigh, NC.

This volume is the second in a series of compilations presenting abstracts and indexes of translations of technical air pollution literature. The 444 entries are grouped into 12 subject categories: General; Emission Sources; Atmospheric Interaction; Measurement Methods; Control Methods; Effects--Human Health; Effects--Plants and Livestock;…

Effective Technology for Recycling Metal. Proceedings of Two Special Workshops.

ERIC Educational Resources Information Center

National Association of Secondary Material Industries, Inc., New York, NY.

The National Association of Secondary Material Industries (NASMI) and the Bureau of Mines have cooperated to sponsor two technically-oriented workshops related to the role of metals recycling and air pollution control technology. The proceedings of these workshops, "Effective Technology and Research for Scrap Metal Recycling" and "Air Pollution…

CO-DEPENDENCIES OF REACTIVE AIR TOXIC AND CRITERIA POLLUTANTS ON EMISSION REDUCTIONS

EPA Science Inventory

It is important to understand the effect of emission controls on the concentrations of ozone, PM_2.5, and hazardous air pollutants simultaneously, in order to evaluate the full range of both health related and economic effects. Until recently, the capability of simultan...

Air pollution and health in Sri Lanka: a review of epidemiologic studies.

PubMed

Nandasena, Yatagama Lokuge S; Wickremasinghe, Ananda R; Sathiakumar, Nalini

2010-06-02

Air pollution is increasingly documented as a threat to public health in most developing countries. Evaluation of current air quality levels, regulatory standards and scientific literature on outdoor and indoor air pollution, and health effects are important to identify the burden, develop and implement interventions and to fill knowledge gaps in Sri Lanka. PUBMED and Medline databases, local journals and conference proceedings were searched for epidemiologic studies pertaining to air pollution and health effects in Sri Lanka. All the studies pertaining to air pollution and health effects were considered. Sixteen studies investigated the association between exposure to ambient or indoor air pollution (IAP) and various health outcomes ranging from respiratory symptoms, low birth weight and lung cancers. Of the sixteen, three used a case control design. Half of the studies collected exposure data only through questionnaires. There were positive associations between air pollution and adverse health effects in all studies. Methodological limitations in most of the studies resulted in poor quantification of risk estimates. A limited number of epidemiological studies in Sri Lanka have investigated the health effects of air pollution. Based on findings of studies and reported air quality levels, air pollution may be considered a neglected public health problem in Sri Lanka.

Are tobacco control policies effective in reducing young adult smoking?

PubMed

Farrelly, Matthew C; Loomis, Brett R; Kuiper, Nicole; Han, Beth; Gfroerer, Joseph; Caraballo, Ralph S; Pechacek, Terry F; Couzens, G Lance

2014-04-01

We examined the influence of tobacco control program funding, smoke-free air laws, and cigarette prices on young adult smoking outcomes. We use a natural experimental design approach that uses the variation in tobacco control policies across states and over time to understand their influence on tobacco outcomes. We combine individual outcome data with annual state-level policy data to conduct multivariable logistic regression models, controlling for an extensive set of sociodemographic factors. The participants are 18- to 25-year-olds from the 2002-2009 National Surveys on Drug Use and Health. The three main outcomes are past-year smoking initiation, and current and established smoking. A current smoker was one who had smoked on at least 1 day in the past 30 days. An established smoker was one who had smoked 1 or more cigarettes in the past 30 days and smoked at least 100 cigarettes in his or her lifetime. Higher levels of tobacco control program funding and greater smoke-free-air law coverage were both associated with declines in current and established smoking (p < .01). Greater coverage of smoke-free air laws was associated with lower past year initiation with marginal significance (p = .058). Higher cigarette prices were not associated with smoking outcomes. Had smoke-free-air law coverage and cumulative tobacco control funding remained at 2002 levels, current and established smoking would have been 5%-7% higher in 2009. Smoke-free air laws and state tobacco control programs are effective strategies for curbing young adult smoking. Copyright © 2014 Society for Adolescent Health and Medicine. All rights reserved.

Are Tobacco Control Policies Effective in Reducing Young Adult Smoking?

PubMed Central

Farrelly, Matthew C.; Loomis, Brett R.; Kuiper, Nicole; Han, Beth; Gfroerer, Joseph; Caraballo, Ralph S.; Pechacek, Terry F.; Couzens, G. Lance

2015-01-01

Purpose We examined the influence of tobacco control program funding, smoke-free air laws, and cigarette prices on young adult smoking outcomes. Methods We use a natural experimental design approach that uses the variation in tobacco control policies across states and over time to understand their influence on tobacco outcomes. We combine individual outcome data with annual state-level policy data to conduct multivariable logistic regression models, controlling for an extensive set of sociodemographic factors. The participants are 18- to 25-year-olds from the 2002–2009 National Surveys on Drug Use and Health. The three main outcomes are past-year smoking initiation, and current and established smoking. A current smoker was one who had smoked on at least 1 day in the past 30 days. An established smoker was one who had smoked 1 or more cigarettes in the past 30 days and smoked at least 100 cigarettes in his or her lifetime. Results Higher levels of tobacco control program funding and greater smoke-free-air law coverage were both associated with declines in current and established smoking (p < .01). Greater coverage of smoke-free air laws was associated with lower past year initiation with marginal significance (p = .058). Higher cigarette prices were not associated with smoking outcomes. Had smoke-free-air law coverage and cumulative tobacco control funding remained at 2002 levels, current and established smoking would have been 5%–7% higher in 2009. Conclusions Smoke-free air laws and state tobacco control programs are effective strategies for curbing young adult smoking. PMID:24268360

Finding of No Significant Impact: Replacement of Chemical Cleaning Line Tinker Air Force Base Oklahoma City, Oklahoma

DTIC Science & Technology

2012-05-01

indoor air quality from installation of a new, improved cleaning line ventilation system. Cultural Resources No adverse effect on cultural...EA) has been prepared to assess the potential effects on the human and natural environment of replacing the chemical cleaning line at Tinker Air...providing improved system monitors and controls, reducing the overall energy consumption of the system, and enabling the system to accommodate larger

Adaptive fuzzy controller for thermal comfort inside the air-conditioned automobile chamber

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

Tong, L.; Yu, B.; Chen, Z.

1999-07-01

In order to meet the passengers' demand for thermal comfort, the adaptive fuzzy logic control design methodology is applied for the automobile airconditioner system. In accordance with the theory of air flow and heat transfer, the air temperature field inside the airconditioned automobile chamber is simulated by a set of simplified half-empirical formula. Then, instead of PMV (Predicted Mean Vote) criterion, RIV (Real Individual Vote) criterion is adopted as the base of the control for passengers' thermal comfort. The proposed controller is applied to the air temperature regulation at the individual passenger position. The control procedure is based on partitioningmore » the state space of the system into cell-groups and fuzzily quantificating the state space into these cells. When the system model has some parameter perturbation, the controller can also adjust its control parameters to compensate for the perturbation and maintain the good performance. The learning procedure shows its ideal effect in both computer simulation and experiments. The final results demonstrate the ideal performance of this adaptive fuzzy controller.« less

Interaction between air pollution exposure and genes in relation to levels of inflammatory markers and risk of myocardial infarction

PubMed Central

Panasevich, Sviatlana; Leander, Karin; Ljungman, Petter; Bellander, Tom; de Faire, Ulf; Pershagen, Göran; Nyberg, Fredrik

2013-01-01

Objectives Air pollution exposure induces cardiovascular effects, possibly via systemic inflammation and coagulation misbalance. Genetic variation may determine individual susceptibility. Our aim was to investigate effect modification by inflammation (Interleukin6 (IL6), tumour necrosis factor-α (TNF-α)) and coagulation (fibrinogen Bβ, plasminogen activator inhibitor-1 (PAI-1)) gene variants on the effect of long-term or short-term air pollution exposure on both blood marker levels and non-fatal myocardial infarction (MI) risk. Design Population-based case–control study with a nested case-crossover study. Gene-environment interactions for short-term and long-term air pollution on blood marker levels were studied in population controls, for long-term exposure on MI risk using case–control design, and for short-term exposure on MI onset using case-crossover design. Setting The Stockholm Heart Epidemiology Programme (SHEEP) conducted in 1992–1994 in Stockholm, Sweden. Spatial modelling was used to assess long-term (up to 30 years retrospectively) air pollution exposure to traffic-NO2 and heating-SO2 emissions at home addresses. Urban background NO2, SO2, PM10 and O3 measurements were used to estimate short-term (up to 5 days) air pollution exposure. Participants 1192 MI cases and 1506 population controls aged 45–70 years. Outcomes The levels of blood markers of inflammation (IL-6, TNF-α) and coagulation (fibrinogen, PAI-1) and MI risk. Results We observed gene–environment interaction for several IL6 and TNF SNPs in relation to inflammation blood marker levels. One-year traffic-NO2 exposure was associated with higher IL-6 levels with each additional IL6-174C allele, and 1-year heating-SO2 exposure with higher levels of TNF-α in TNF-308AA homozygotes versus −308G carriers. Short-term air pollution exposure also interacted with IL6 and TNF in relation to marker levels. The risk of MI followed the effect on blood markers in each genotype group. Conclusions Genetic variants in IL6 and TNF may modify effects of long-term and short-term air pollution exposure on inflammatory marker levels and MI risk. PMID:24056475

The effect of autoimmune retinopathy on retinal vessel oxygen saturation.

PubMed

Waizel, Maria; Türksever, Cengiz; Todorova, Margarita G

2018-05-22

To study the retinal vessel oxygen saturation alterations in patients with autoimmune retinopathy (AIR) and patients with autoimmune retinopathy associated with retinitis pigmentosa (AIR-RP) in comparison with healthy controls and patients with isolated retinitis pigmentosa (RP). Prospective, cross-sectional, and non-interventional study. Retinal vessel oximetry (RO) was performed on a total of 139 eyes: six eyes suffering from AIR and four eyes with AIR-RP were compared to 59 healthy control eyes and to 70 eyes with RP. A computer-based program of the retinal vessel analyser unit (IMEDOS Systems UG, Jena, Germany) was used to evaluate retinal vessel oxygen saturation. The mean oxygen saturation in the first and second branch retinal arterioles (A-SO 2 ) and venules (V-SO 2 ) were measured and their difference (A-V SO 2 ) was calculated. In addition, we measured the diameter of the retinal arterioles (D-A) and venules (D-V). Oxygen metabolism is altered in patients with isolated AIR and AIR-RP. Both, AIR and AIR-RP groups, differed from healthy controls showing significantly higher V-SO 2 values and significantly lower A-V SO 2 values (p < 0.025). In addition, the AIR-RP group could be differentiated from eyes suffering from isolated RP by means of significantly higher V-SO 2 values. Comparing retinal vessel diameters, both, the AIR and AIR-RP groups, presented with significant arterial (p = 0.05) and venular (p < 0.03) vessel attenuation than the healthy control group. Based on our results, in analogy to patients suffering from RP, oxygen metabolism seems to be altered in AIR patients.

The Human Performance Envelope: Past Research, Present Activities and Future Directions

NASA Technical Reports Server (NTRS)

Edwards, Tamsyn

2017-01-01

Air traffic controllers (ATCOs) must maintain a consistently high level of human performance in order to maintain flight safety and efficiency. In current control environments, performance-influencing factors such as workload, fatigue and situation awareness can co-occur, and interact, to effect performance. However, multifactor influences and the association with performance are under-researched. This study utilized a high fidelity human in the loop enroute air traffic control simulation to investigate the relationship between workload, situation awareness and ATCO performance. The study aimed to replicate and extend Edwards, Sharples, Wilson and Kirwans (2012) previous study and confirm multifactor interactions with a participant sample of ex-controllers. The study also aimed to extend Edwards et als previous research by comparing multifactor relationships across 4 automation conditions. Results suggest that workload and SA may interact to produce a cumulative impact on controller performance, although the effect of the interaction on performance may be dependent on the context and amount of automation present. Findings have implications for human-automation teaming in air traffic control, and the potential prediction and support of ATCO performance.

Automated Air Traffic Control Operations with Weather and Time-Constraints: A First Look at (Simulated) Far-Term Control Room Operations

NASA Technical Reports Server (NTRS)

Prevot, Thomas; Homola, Jeffrey R.; Martin, Lynne H.; Mercer, Joey S.; Cabrall, Christopher C.

2011-01-01

In this paper we discuss results from a recent high fidelity simulation of air traffic control operations with automated separation assurance in the presence of weather and time-constraints. We report findings from a human-in-the-loop study conducted in the Airspace Operations Laboratory (AOL) at the NASA Ames Research Center. During four afternoons in early 2010, fifteen active and recently retired air traffic controllers and supervisors controlled high levels of traffic in a highly automated environment during three-hour long scenarios, For each scenario, twelve air traffic controllers operated eight sector positions in two air traffic control areas and were supervised by three front line managers, Controllers worked one-hour shifts, were relieved by other controllers, took a 3D-minute break, and worked another one-hour shift. On average, twice today's traffic density was simulated with more than 2200 aircraft per traffic scenario. The scenarios were designed to create peaks and valleys in traffic density, growing and decaying convective weather areas, and expose controllers to heavy and light metering conditions. This design enabled an initial look at a broad spectrum of workload, challenge, boredom, and fatigue in an otherwise uncharted territory of future operations. In this paper we report human/system integration aspects, safety and efficiency results as well as airspace throughput, workload, and operational acceptability. We conclude that, with further refinements. air traffic control operations with ground-based automated separation assurance can be an effective and acceptable means to routinely provide very high traffic throughput in the en route airspace.

Effects of genetic strain on stress-induced weight and body fat loss in rats: Application to air pollution research

EPA Science Inventory

Exposure to some air pollutants is suspected of contributing to obesity. Hazelton chambers are commonly used in air pollution studies but we found unexpected reductions in body weight and body fat of rats housed in Hazelton chambers under control conditions. We suspect that stres...

76 FR 70656 - Approval and Promulgation of Implementation Plans and Designations of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-15

... taking? II. What is the effect of this action? III. What is EPA's response to comments? IV. What is EPA's... comments. In this action, EPA is responding to those adverse comments. II. What is the effect of this... no effect on control measures, or air quality, in the area. For example, contrary to Commenter's...

Air pollution management and control in Latin America and the Caribbean: implications for climate change.

PubMed

Riojas-Rodríguez, Horacio; da Silva, Agnes Soares; Texcalac-Sangrador, José Luis; Moreno-Banda, Grea Litai

2016-09-01

To assess the status of the legal framework for air quality control in all countries of Latin America and Caribbean (LAC); to determine the current distribution of air monitoring stations and mean levels of air pollutants in all capital and large cities (more than 100 000 inhabitants); and to discuss the implications for climate change and public policymaking. From January 2015-February 2016, searches were conducted of online databases for legislation, regulations, policies, and air pollution programs, as well as for the distribution of monitoring stations and the mean annual levels of air pollution in all LAC countries. Only 117 cities distributed among 17 of 33 LAC countries had official information on ground level air pollutants, covering approximately 146 million inhabitants. The annual mean of inhalable particles concentration in most of the cities were over the World Health Organization Air Quality Guidelines; notably, only Bolivia, Peru, and Guatemala have actually adopted the guidelines. Most of the cities did not have information on particulate matter of 2.5 microns or less, and only a few measured black carbon. The air quality regulatory framework should be updated to reflect current knowledge on health effects. Monitoring and control of ground level pollutants should be extended and strengthened to increase awareness and protect public health. Using the co-benefits of air pollution control for health and climate as a framework for policy and decision-making in LAC is recommended.

Active control of continuous air jet with bifurcated synthetic jets

NASA Astrophysics Data System (ADS)

Dančová, Petra; Vít, Tomáš; Jašíková, Darina; Novosád, Jan

The synthetic jets (SJs) have many significant applications and the number of applications is increasing all the time. In this research the main focus is on the primary flow control which can be used effectively for the heat transfer increasing. This paper deals with the experimental research of the effect of two SJs worked in the bifurcated mode used for control of an axisymmetric air jet. First, the control synthetic jets were measured alone. After an adjustment, the primary axisymmetric jet was added in to the system. For comparison, the primary flow without synthetic jets control was also measured. All experiments were performed using PIV method whereby the synchronization between synthetic jets and PIV system was necessary to do.

Joint Effects of Ambient Air Pollutants on Pediatric Asthma ...

EPA Pesticide Factsheets

Background: Because ambient air pollution exposure occurs in the form of mixtures, consideration of joint effects of multiple pollutants may advance our understanding of air pollution health effects. Methods: We assessed the joint effect of selected ambient air pollutant combinations (groups of oxidant, secondary, traffic, power plant, and criteria pollutants constructed using combinations of criteria gases, fine particulate matter (PM2.5) and PM2.5 components) on warm season pediatric asthma emergency department (ED) visits in Atlanta during 1998-2004. Joint effects were assessed using multi-pollutant Poisson generalized linear models controlling for time trends, meteorology and daily non-asthma respiratory ED visit counts. Rate ratios (RR) were calculated for the combined effect of an interquartile-range increment in the concentration of each pollutant. Results: Increases in all of the selected pollutant combinations were associated with increases in pediatric asthma ED visits [e.g., joint effect rate ratio=1.13 (95% confidence interval 1.06-1.21) for criteria pollutants (including ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and PM2.5)]. Joint effect estimates were smaller than estimates calculated based on summing results from single-pollutant models, due to control for confounding. Compared with models without interactions, joint effect estimates from models including first-order pollutant interactions were similar for oxidant a

The Effects of Shared Information on Pilot-Controller Situation Awareness And Re-Route Negotiation

NASA Technical Reports Server (NTRS)

Farley, Todd C.; Hansman, R. John; Endsley, Mica R.; Amonlirdviman, Keith

1999-01-01

The effect of shared information is assessed in terms of pilot-controller negotiating behavior and shared situation awareness. Pilot goals and situation awareness requirements are developed and compared against those of air traffic controllers to identify areas of common and competing interest. An exploratory, part-task simulator experiment is described which evaluates the extent to which shared information may lead pilots and controllers to cooperate or compete when negotiating route amendments. Results are presented which indicate that shared information enhances situation awareness and can engender more collaborative interaction between pilots and air traffic controllers. Furthermore, the value of providing controllers with a good-quality weather overlay on their plan view displays is demonstrated. Observed improvements in situation awareness and separation assurance are discussed.

Mental Effort and Performance as Determinants for the Dynamic Selection of Learning Tasks in Air Traffic Control Training

ERIC Educational Resources Information Center

Salden, Ron J.C.M.; Paas, Fred; Broers, Nick J.; van Merrienboer, Jeroen J. G.

2004-01-01

The differential effects of four task selection methods on training efficiency and transfer in computer-based training for Air Traffic Control were investigated. A non-dynamic condition, in which the learning tasks were presented to the participants in a fixed, predetermined sequence, was compared to three dynamic conditions, in which learning…

Impacts of air pollution wave on years of life lost: A crucial way to communicate the health risks of air pollution to the public.

PubMed

Huang, Jing; Pan, Xiaochuan; Guo, Xinbiao; Li, Guoxing

2018-04-01

Limited studies have explored the impacts of exposure to sustained high levels of air pollution (air pollution wave) on mortality. Given that the frequency, intensity and duration of air pollution wave has been increasing in highly polluted regions recently, understanding the impacts of air pollution wave is crucial. In this study, air pollution wave was defined as 2 or more consecutive days with air pollution index (API) > 100. The impacts of air pollution wave on years of life lost (YLL) due to non-accidental, cardiovascular and respiratory deaths were evaluated by considering both consecutive days with high levels of air pollution and daily air pollution levels in Tianjin, China, from 2006 to 2011. The results showed the durational effect of consecutive days with high levels of air pollution was substantial in addition to the effect of daily air pollution. For instance, the durational effect was related to an increase in YLL of 116.6 (95% CI: 4.8, 228.5) years from non-accidental deaths when the air pollution wave was sustained for 4 days, while the corresponding daily air pollution's effect was 121.2 (95% CI: 55.2, 187.1) years. A better interpretation of the health risks of air pollution wave is crucial for air pollution control policy making and public health interventions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Factors Influencing the Decisions and Actions of Pilots and Air Traffic Controllers in Three Plausible NextGen Environments

NASA Technical Reports Server (NTRS)

Vu, Kim-Phuong L.; Strybel, Thomas Z.; Battiste, Vernol; Johnson, Walter

2011-01-01

In the current air traffic management (ATM) system, pilots and air traffic controllers have well-established roles and responsibilities: pilots fly aircraft and are concerned with energy management, fuel efficiency, and passenger comfort; controllers separate aircraft and are concerned with safety and management of traffic flows. Despite having different goals and obligations, both groups must be able to effectively communicate and interact with each other for the ATM system to work. This interaction will become even more challenging as traffic volume increases dramatically in the near future. To accommodate this increase, by 2025 the national air transportation system in the U.S. will go through a transformation that will modernize the ATM system and make it safer, more effective, and more efficient. This new system, NextGen, will change how pilots and controllers perform their tasks by incorporating advanced technologies and employing new procedures. It will also distribute responsibility between pilots, controllers and automation over such tasks as maintaining aircraft separation. The present chapter describes three plausible concepts of operations that allocate different ATM responsibilities to these groups. We describe how each concept changes the role of each operator and the types of decisions and actions performed by them.

The effectiveness of an air cleaner in controlling droplet/aerosol particle dispersion emitted from a patient's mouth in the indoor environment of dental clinics.

PubMed

Chen, Chun; Zhao, Bin; Cui, Weilin; Dong, Lei; An, Na; Ouyang, Xiangying

2010-07-06

Dental healthcare workers (DHCWs) are at high risk of occupational exposure to droplets and aerosol particles emitted from patients' mouths during treatment. We evaluated the effectiveness of an air cleaner in reducing droplet and aerosol contamination by positioning the device in four different locations in an actual dental clinic. We applied computational fluid dynamics (CFD) methods to solve the governing equations of airflow, energy and dispersion of different-sized airborne droplets/aerosol particles. In a dental clinic, we measured the supply air velocity and temperature of the ventilation system, the airflow rate and the particle removal efficiency of the air cleaner to determine the boundary conditions for the CFD simulations. Our results indicate that use of an air cleaner in a dental clinic may be an effective method for reducing DHCWs' exposure to airborne droplets and aerosol particles. Further, we found that the probability of droplet/aerosol particle removal and the direction of airflow from the cleaner are both important control measures for droplet and aerosol contamination in a dental clinic. Thus, the distance between the air cleaner and droplet/aerosol particle source as well as the relative location of the air cleaner to both the source and the DHCW are important considerations for reducing DHCWs' exposure to droplets/aerosol particles emitted from the patient's mouth during treatments.

The effectiveness of an air cleaner in controlling droplet/aerosol particle dispersion emitted from a patient's mouth in the indoor environment of dental clinics

PubMed Central

Chen, Chun; Zhao, Bin; Cui, Weilin; Dong, Lei; An, Na; Ouyang, Xiangying

2010-01-01

Dental healthcare workers (DHCWs) are at high risk of occupational exposure to droplets and aerosol particles emitted from patients' mouths during treatment. We evaluated the effectiveness of an air cleaner in reducing droplet and aerosol contamination by positioning the device in four different locations in an actual dental clinic. We applied computational fluid dynamics (CFD) methods to solve the governing equations of airflow, energy and dispersion of different-sized airborne droplets/aerosol particles. In a dental clinic, we measured the supply air velocity and temperature of the ventilation system, the airflow rate and the particle removal efficiency of the air cleaner to determine the boundary conditions for the CFD simulations. Our results indicate that use of an air cleaner in a dental clinic may be an effective method for reducing DHCWs' exposure to airborne droplets and aerosol particles. Further, we found that the probability of droplet/aerosol particle removal and the direction of airflow from the cleaner are both important control measures for droplet and aerosol contamination in a dental clinic. Thus, the distance between the air cleaner and droplet/aerosol particle source as well as the relative location of the air cleaner to both the source and the DHCW are important considerations for reducing DHCWs' exposure to droplets/aerosol particles emitted from the patient's mouth during treatments. PMID:20031985

Chronic effects of air pollution on respiratory health in Southern California children: findings from the Southern California Children's Health Study.

PubMed

Chen, Zhanghua; Salam, Muhammad T; Eckel, Sandrah P; Breton, Carrie V; Gilliland, Frank D

2015-01-01

Outdoor air pollution is one of the leading contributors to adverse respiratory health outcomes in urban areas around the world. Children are highly sensitive to the adverse effects of air pollution due to their rapidly growing lungs, incomplete immune and metabolic functions, patterns of ventilation and high levels of outdoor activity. The Children's Health Study (CHS) is a continuing series of longitudinal studies that first began in 1993 and has focused on demonstrating the chronic impacts of air pollution on respiratory illnesses from early childhood through adolescence. A large body of evidence from the CHS has documented that exposures to both regional ambient air and traffic-related pollutants are associated with increased asthma prevalence, new-onset asthma, risk of bronchitis and wheezing, deficits of lung function growth, and airway inflammation. These associations may be modulated by key genes involved in oxidative-nitrosative stress pathways via gene-environment interactions. Despite successful efforts to reduce pollution over the past 40 years, air pollution at the current levels still brings many challenges to public health. To further ameliorate adverse health effects attributable to air pollution, many more toxic pollutants may require regulation and control of motor vehicle emissions and other combustion sources may need to be strengthened. Individual interventions based on personal susceptibility may be needed to protect children's health while control measures are being implemented.

Investigation of air transportation technology at Princeton University, 1985

NASA Technical Reports Server (NTRS)

Stengel, Robert F.

1987-01-01

The program proceeded along five avenues during 1985. Guidance and control strategies for penetration of microbursts and wind shear, application of artificial intelligence in flight control and air traffic control systems, the use of voice recognition in the cockpit, the effects of control saturation on closed-loop stability and response of open-loop unstable aircraft, and computer aided control system design are among the topics briefly considered. Areas of investigation relate to guidance and control of commercial transports as well as general aviation aircraft. Interaction between the flight crew and automatic systems is the subject of principal concern.

Air cleaning technologies: an evidence-based analysis.

PubMed

2005-01-01

This health technology policy assessment will answer the following questions: When should in-room air cleaners be used?How effective are in-room air cleaners?Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone?What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan?The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario's capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry's Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering, and personal protection methods. Engineering methods that are usually carried out by the building's heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system's effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes zoster, whereas close contact is required for the direct transmission of infectious diseases transmitted by droplets, such as influenza (the flu) and SARS. In-room air cleaners are supplied as portable or fixed devices. Fixed devices can be attached to either a wall or ceiling and are preferred over portable units because they have a greater degree of reliability (if installed properly) for achieving adequate room air mixing and airflow patterns, which are important for optimal effectiveness. Through a method of air recirculation, an in-room air cleaner can be used to increase room ventilation rates and if used to exhaust air out of the room it can create a negative-pressure room for airborne infection isolation (AII) when the building's HVAC system cannot do so. A negative-pressure room is one where clean air flows into the room but contaminated air does not flow out of it. Contaminated room air is pulled into the in-room air cleaner and cleaned by passing through a series of filters, which remove the airborne infectious pathogens. The cleaned air is either recirculated into the room or exhausted outside the building. By filtering contaminated room air and then recirculating the cleaned air into the room, an in-room air cleaner can improve the room's ventilation. By exhausting the filtered air to the outside the unit can create a negative-pressure room. There are many types of in-room air cleaners. They vary widely in the airflow rates through the unit, the type of air cleaning technology used, and the technical design. Crucial to maximizing the efficiency of any in-room air cleaner is its strategic placement and set-up within a room, which should be done in consultation with ventilation engineers, infection control experts, and/or industrial hygienists. A poorly positioned air cleaner may disrupt airflow patterns within the room and through the air cleaner, thereby compromising its air cleaning efficiency. The effectiveness of an in-room air cleaner to remove airborne pathogens from room air depends on several factors, including the airflow rate through the unit's filter and the airflow patterns in the room. Tested under a variety of conditions, in-room air cleaners, including portable or ceiling mounted units with either a HEPA or a non-HEPA filter, portable units with UVGI lights only, or ceiling mounted units with combined HEPA filtration and UVGI lights, have been estimated to be between 30% and 90%, 99% and 12% and 80% effective, respectively. However, and although their effectiveness is variable, the United States Centers for Disease Control and Prevention has acknowledged in-room air cleaners as alternative technology for increasing room ventilation when this cannot be achieved by the building's HVAC system with preference given to fixed recirculating systems over portable ones. Importantly, the use of an in-room air cleaner does not preclude either the need for health care workers and visitors to use personal protective equipment (N95 mask or equivalent) when entering AII rooms or health care facilities from meeting current regulatory requirements for airflow rates (ventilation rates) in buildings and airflow differentials for effective negative-pressure rooms. The Plasmacluster ion technology, developed in 2000, is an air purification technology. Its manufacturer, Sharp Electronics Corporation, says that it can disable airborne microorganisms through the generation of both positive and negative ions. (1) The functional unit is the hydroxyl, which is a molecule comprised of one oxygen molecule and one hydrogen atom. Plasmacluster ion air purifier uses a multilayer filter system composed of a prefilter, a carbon filter, an antibacterial filter, and a HEPA filter, combined with an ion generator to purify the air. The ion generator uses an alternating plasma discharge to split water molecules into positively and negatively charged ions. When these ions are emitted into the air, they are surrounded by water molecules and form cluster ions which are attracted to airborne particles. The cluster ion surrounds the airborne particle, and the positive and negative ions react to form hydroxyls. These hydroxyls steal the airborne particle's hydrogen atom, which creates a hole in the particle's outer protein membrane, thereby rendering it inactive. Because influenza is primarily acquired by large droplets and direct and indirect contact with an infectious person, any in-room air cleaner will have little benefit in controlling and preventing its spread. Therefore, there is no role for the Plasmacluster ion air purifier or any other in-room air cleaner in the control of the spread of influenza. Accordingly, for purposes of this review, the Medical Advisory Secretariat presents no further analysis of the Plasmacluster. The objective of the systematic review was to determine the effectiveness of in-room air cleaners with built in UVGI lights and HEPA filtration compared with those using HEPA filtration only. The Medical Advisory Secretariat searched the databases of MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, INAHATA (International Network of Agencies for Health Technology Assessment), Biosis Previews, Bacteriology Abstracts, Web of Science, Dissertation Abstracts, and NIOSHTIC 2. A meta-analysis was conducted if adequate data was available from 2 or more studies and where statistical and clinical heterogeneity among studies was not an issue. Otherwise, a qualitative review was completed. The GRADE system was used to summarize the quality of the body of evidence comprised of 1 or more studies. There were no existing health technology assessments on air cleaning technology located during the literature review. The literature search yielded 59 citations of which none were retained. (ABSTRACT TRUNCATED)

A Multicity Analysis of the Short-Term Effects of Air Pollution on the Chronic Obstructive Pulmonary Disease Hospital Admissions in Shandong, China.

PubMed

Liu, Yi; Sun, Jingjie; Gou, Yannong; Sun, Xiubin; Li, Xiujun; Yuan, Zhongshang; Kong, Lizhi; Xue, Fuzhong

2018-04-17

Although there is growing evidence linking chronic obstructive pulmonary disease (COPD) hospital admissions to the exposure to ambient air pollution, the effect can vary depending on the local geography, pollution type, and pollution level. The number of large-scale multicity studies remains limited in China. This study aims to assess the short-term effects of ambient air pollution (PM 2.5 , PM 10 , SO₂, NO₂) on chronic obstructive pulmonary disease hospital admissions from 2015 to 2016, with a total of 216,159 records collected from 207 hospitals in 17 cities all over the Shandong province, east China. Generalized additive models and penalized splines were applied to study the data whilst controlling for confounding meteorological factors and long-term trends. The air pollution was analyzed with 0–6 day lag effects and the percentage change of hospital admissions was assessed for a 10-μg/m³ increase in the air pollution levels. We also examined the percentage changes for different age groups and gender, respectively. The results showed that air pollution was significantly associated with adverse health outcomes and stronger effects were observed for females. The air pollution health effects were also impacted by geographical factors such that the air pollution had weaker health effects in coastal cities.

Air Force Science & Technology Issues & Opportunities Regarding High Performance Embedded Computing

DTIC Science & Technology

2009-09-23

Challenges by Domain * Air: Persistent air dominance is at risk * Increasingly effective air defenses * Proliferation of 5th generation fighters, cheap cruise missiles, and UASs * Light-speed war possibilities are terrifying * Space: Now a contested domain * Increasingly important * Increasingly vulnerable * Cyber: Cyber warfare has begun * We don’t control the battlespace * We rely on it more and more * We can’t find the enemy.

[Study on emission standard system of air pollutants].

PubMed

Jiang, Mei; Zhang, Guo-Ning; Zhang, Ming-Hui; Zou, Lan; Wei, Yu-Xia; Ren, Chun

2012-12-01

Scientific and reasonable emission standard system of air pollutants helps to systematically control air pollution, enhance the protection of the atmospheric environment effect and improve the overall atmospheric environment quality. Based on the study of development, situation and characteristics of national air pollutants emission standard system, the deficiencies of system were pointed out, which were not supportive, harmonious and perfect, and the improvement measures of emission standard system were suggested.

Information needs related to extension service and community outreach.

PubMed

Bottcher, Robert W

2003-06-01

Air quality affects everyone. Some people are affected by air quality impacts, regulations, and technological developments in several ways. Stakeholders include the medical community, ecologists, government regulators, industries, technology providers, academic professionals, concerned citizens, the news media, and elected officials. Each of these groups may perceive problems and opportunities differently, but all need access to information as it is developed. The diversity and complexity of air quality problems contribute to the challenges faced by extension and outreach professionals who must communicate with stakeholders having diverse backgrounds. Gases, particulates, biological aerosols, pathogens, and odors all require expensive and relatively complex technology to measure and control. Economic constraints affect the ability of regulators and others to measure air quality, and industry and others to control it. To address these challenges, while communicating air quality research results and concepts to stakeholders, three areas of information needs are evident. (1) A basic understanding of the fundamental concepts regarding air pollutants and their measurement and control is needed by all stakeholders; the Extension Specialist, to be effective, must help people move some distance up the learning curve. (2) Each problem or set of problems must be reasonably well defined since comprehensive solution of all problems simultaneously may not be feasible; for instance, the solution of an odor problem associated with animal production may not address atmospheric effects due to ammonia emissions. (3) The integrity of the communication process must be preserved by avoiding prejudice and protectionism; although stakeholders may seek to modify information to enhance their interests, extension and outreach professionals must be willing to present unwelcome information or admit to a lack of information. A solid grounding in fundamental concepts, careful and fair problem definition, and a resolute commitment to integrity and credibility will enable effective communication of air quality information to and among diverse stakeholders.

Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners

PubMed Central

Batterman, S.; Du, L.; Mentz, G.; Mukherjee, B.; Parker, E.; Godwin, C.; Chin, J.-Y.; O'Toole, A.; Robins, T.; Rowe, Z.; Lewis, T.

2014-01-01

This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84 ± 27%, but dropped to 63 ± 33% in subsequent seasons. In months when households were not visited, use averaged only 34 ± 30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. PMID:22145709

Procedural errors in air traffic control: effects of traffic density, expertise, and automation.

PubMed

Di Nocera, Francesco; Fabrizi, Roberto; Terenzi, Michela; Ferlazzo, Fabio

2006-06-01

Air traffic management requires operators to frequently shift between multiple tasks and/or goals with different levels of accomplishment. Procedural errors can occur when a controller accomplishes one of the tasks before the entire operation has been completed. The present study had two goals: first, to verify the occurrence of post-completion errors in air traffic control (ATC) tasks; and second, to assess effects on performance of medium term conflict detection (MTCD) tools. There were 18 military controllers who performed a simulated ATC task with and without automation support (MTCD vs. manual) in high and low air traffic density conditions. During the task, which consisted of managing several simulated flights in an enroute ATC scenario, a trace suddenly disappeared "after" the operator took the aircraft in charge, "during" the management of the trace, or "before" the pilot's first contact. In the manual condition, only the fault type "during" was found to be significantly different from the other two. On the contrary, when in the MTCD condition, the fault type "after" generated significantly less errors than the fault type "before." Additionally, automation was found to affect performance of junior controllers, whereas seniors' performance was not affected. Procedural errors can happen in ATC, but automation can mitigate this effect. Lack of benefits for the "before" fault type may be due to the fact that operators extend their reliance to a part of the task that is unsupported by the automated system.

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2012 CFR

2012-07-01

... device's category will be based on: (1) Engineering principles governing operation of the device; (2... mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2014 CFR

2014-07-01

... device's category will be based on: (1) Engineering principles governing operation of the device; (2... mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

40 CFR 610.21 - Device functional category and vehicle system effects.

Code of Federal Regulations, 2013 CFR

2013-07-01

... device's category will be based on: (1) Engineering principles governing operation of the device; (2... mechanical) All. Vapor Injectors All. Choke controls 1, 2, and 4. Air filters 1, 2, and 4. Fuel-air...

Relationship between air pollution and pre-eclampsia in pregnant women: a case-control study.

PubMed

Nahidi, F; Gholami, R; Rashidi, Y; Majd, H Alavi

2014-01-09

Pre-eclampsia is the main cause of maternal and fetal death and disability worldwide. Its incidence in the Islamic Republic of Iran is 5%-12%. Air pollution has been reported to be one of the causative factors, and this case-control study determined its effect on pre-eclampsia in 195 pregnant women (65 with pre-eclampsia and 130 without) admitted to hospitals in Tehran. Women were divided into high and low exposure groups according to the mean density of exposure to pollutants during pregnancy. There was no statistically significant relationship between exposure to air pollutants including CO, particulate matter, SO2, NO2 and O3 and pre-eclampsia. The combined effect was also not significant. Air pollution is one of the problems of modern society and its avoidance is almost impossible for pregnant women. This study should reduce concern about pregnant women living in polluted cities.

Setting limits: Using air pollution thresholds to protect and restore US ecosystems

USGS Publications Warehouse

Fenn, Mark E.; Lambert, Kathleen F.; Blett, Tamara F.; Burns, Douglas A.; Pardo, Linda H.; Lovett, Gary M.; Haeuber, Richard A.; Evers, David C.; Driscoll, Charles T.; Jeffries, Dean S.

2011-01-01

More than four decades of research provide unequivocal evidence that sulfur, nitrogen, and mercury pollution have altered, and will continue to alter, our nation's lands and waters. The emission and deposition of air pollutants harm native plants and animals, degrade water quality, affect forest productivity, and are damaging to human health. Many air quality policies limit emissions at the source but these control measures do not always consider ecosystem impacts. Air pollution thresholds at which ecological effects are observed, such as critical loads, are effective tools for assessing the impacts of air pollution on essential ecosystem services and for informing public policy. U.S. ecosystems can be more effectively protected and restored by using a combination of emissions-based approaches and science-based thresholds of ecosystem damage.

Cleansing orthodontic brackets with air-powder polishing: effects on frictional force and degree of debris.

PubMed

Leite, Brisa Dos Santos; Fagundes, Nathalia Carolina Fernandes; Aragón, Mônica Lídia Castro; Dias, Carmen Gilda Barroso Tavares; Normando, David

2016-01-01

Debris buildup on the bracket-wire interface can influence friction. Cleansing brackets with air-powder polishing can affect this process. The aim of this study was to evaluate the frictional force and amount of debris remaining on orthodontic brackets subjected to prophylaxis with air-powder polishing. Frictional force and debris buildup on the surface of 28 premolar brackets were evaluated after orthodontic treatment. In one hemiarch, each bracket was subjected to air-powder polishing (n = 14) for five seconds, while the contralateral hemiarch (n = 14) served as control. Mechanical friction tests were performed and images of the polished bracket surfaces and control surfaces were examined. Wilcoxon test was applied for comparative analysis between hemiarches at p < 0.05. Brackets that had been cleaned with air-powder polishing showed lower friction (median = 1.27 N) when compared to the control surfaces (median = 4.52 N) (p < 0.01). Image analysis showed that the control group exhibited greater debris buildup (median = 2.0) compared with the group that received prophylaxis with air-powder polishing (median = 0.5) (p < 0.05). Cleansing orthodontic brackets with air-powder polishing significantly reduces debris buildup on the bracket surface while decreasing friction levels observed during sliding mechanics.

Design and application of an inertial impactor in combination with an ATP bioluminescence detector for in situ rapid estimation of the efficacies of air controlling devices on removal of bioaerosols.

PubMed

Yoon, Ki Young; Park, Chul Woo; Byeon, Jeong Hoon; Hwang, Jungho

2010-03-01

We proposed a rapid method to estimate the efficacies of air controlling devices in situ using ATP bioluminescence in combination with an inertial impactor. The inertial impactor was designed to have 1 mum of cutoff diameter, and its performance was estimated analytically, numerically, and experimentally. The proposed method was characterized using Staphylococcus epidermidis, which was aerosolized with a nebulizer. The bioaerosol concentrations were estimated within 25 min using the proposed method without a culturing process, which requires several days for colony formation. A linear relationship was obtained between the results of the proposed ATP method (RLU/m(3)) and the conventional culture-based method (CFU/m(3)), with R(2) 0.9283. The proposed method was applied to estimate the concentration of indoor bioaerosols, which were identified as a mixture of various microbial species including bacteria, fungi, and actinomycetes, in an occupational indoor environment, controlled by mechanical ventilation and an air cleaner. Consequently, the proposed method showed a linearity with the culture-based method for indoor bioaerosols with R(2) 0.8189, even though various kinds of microorganisms existed in the indoor air. The proposed method may be effective in monitoring the changes of relative concentration of indoor bioaerosols and estimating the effectiveness of air control devices in indoor environments.

A Quasi-Experimental Analysis of Elementary School Absences and Fine Particulate Air Pollution

PubMed Central

Hales, Nicholas M.; Barton, Caleb C.; Ransom, Michael R.; Allen, Ryan T.; Pope, C. Arden

2016-01-01

Abstract Fine particulate air pollution (PM2.5) has been associated with many adverse health outcomes including school absences. Specifically, a previous study in the Utah Valley area, conducted during a time with relatively high air pollution exposure, found significant positive correlations between school absences and air pollution. We examined the hypothesis that ambient PM2.5 exposures are associated with elementary school absences using a quasi-natural experiment to help control for observed and unobserved structural factors that influence school absences. The Alpine, Provo, and Salt Lake City school districts are located in valleys subject to daily mean PM2.5 concentrations almost twice as high as those in the Park City School District. We used seminonparametric generalized additive Poisson regression models to evaluate associations between absences and daily PM2.5 levels in the 3 districts that were exposed to the most pollution while using Park City absences as a quasi-control. The study covered 3 school years (2011/12-2013/14). School absences were most strongly associated with observed structural factors such as seasonal trends across school years, day-of-week effects, holiday effects, weather, etc. However, after controlling for these structural factors directly and using a control district, a 10 μg/m3 increase in PM2.5 was associated with an approximately 1.7% increase in daily elementary school absences. Exposure to ambient air pollution can contribute to elementary school absences, although this effect is difficult to disentangle from various other factors. PMID:26945391

Cabin air filtration: helping to protect occupants from infectious diseases.

PubMed

Bull, Karen

2008-05-01

Presentation made at the Aviation Health Conference, London, November 2006. In modern aircraft, the air in the cabin is provided by the environmental control system (ECS) and consists of approximately 50% outside air (engine 'bleed air') mixed with approximately 50% filtered, recirculated air. This paper describes how modern aircraft cabin air filters are effective at removing airborne particulate contamination (such as bacteria and viruses) from the recirculated air system. It also describes one of the technological solutions that is currently available to treat any odours or volatile organic compounds (VOCs) that may be present in the aircraft ECS.

Evaluating the Effects of Emission Reductions on Multiple Pollutants Simultaneously

EPA Science Inventory

Modeling studies over the Philadelphia metropolitan area have examined how emission control strategies might affect several types of air pollutants simultaneously. This study supports considering effects of multiple pollutants in determining optimum pollution control strategies. ...

Economic Impacts from PM2.5 Pollution-Related Health Effects: A Case Study in Shanghai.

PubMed

Wu, Rui; Dai, Hancheng; Geng, Yong; Xie, Yang; Masui, Toshihiko; Liu, Zhiqing; Qian, Yiying

2017-05-02

PM 2.5 pollution-related diseases cause additional medical expenses and work time loss, leading to macroeconomic impact in high PM 2.5 concentration areas. Previous economic impact assessments of air pollution focused on benefits from environmental regulations while ignoring climate policies. In this study, we examine the health and economic impacts from PM 2.5 pollution under various air pollution control strategies and climate policies scenarios in the megacity of Shanghai. The estimation adopts an integrated model combining a Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model, exposure-response functions (ERFs), and a computable general equilibrium (CGE) model. The results show that without control measures, Shanghai's mortality caused by PM 2.5 pollution are estimated to be 192 400 cases in 2030 and the work time loss to be 72.1 h/cap annually. The corresponding GDP values and welfare losses would be approximately 2.26% and 3.14%, respectively. With an estimated control cost of 0.76% of local GDP, Shanghai would gain approximately 1.01% of local GDP through local air pollution control measures and climate policies. Furthermore, the application of multiregional integrated control strategies in neighboring provinces would be the most effective in reducing PM 2.5 concentration in Shanghai, leading to only 0.34% of GDP loss. At the sectoral level, labor-intensive sectors suffer more output loss from PM 2.5 pollution. Sectors with the highest control costs include power generation, iron and steel, and transport. The results indicate that the combination of multiregional integrated air pollution control strategies and climate policies would be cost-beneficial for Shanghai.

[Research and production of air cleaner for traveller train carriage].

PubMed

Bi, Z

1998-07-01

After the traveller train carriage is closed, the air pollution would be serious in the carriage. In order to control the air pollution, the air cleaning technology must be studied and the air cleaner for the carriage must be designed. The authors discussed. 1. Working out a technology scheme and main technology parameter for the air cleaner, and the structure design of the air cleaner. 2. Texting the function and performance of the air cleaner. 3. Investigating the effectiveness of the cleaner in same train sections. Thereby it will be confirmed that the air cleaner can improve the air environment in the carriage, and give convincingly security to the health of attendants and travellers.

A modeling study of coarse particulate matter pollution in Beijing: regional source contributions and control implications for the 2008 summer Olympics

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

Litao Wang; Jiming Hao; Kebin He

In the last 10 yr, Beijing has made a great effort to improve its air quality. However, it is still suffering from regional coarse particulate matter (PM10) pollution that could be a challenge to the promise of clean air during the 2008 Olympics. To provide scientific guidance on regional air pollution control, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality Model (CMAQ) air quality modeling system was used to investigate the contributions of emission sources outside the Beijing area to pollution levels in Beijing. The contributions to the PM10 concentrations in Beijing were assessed formore » the following sources: power plants, industry, domestic sources, transportation, agriculture, and biomass open burning. In January, it is estimated that on average 22% of the PM10 concentrations can be attributed to outside sources, of which domestic and industrial sources contributed 37 and 31%, respectively. In August, as much as 40% of the PM10 concentrations came from regional sources, of which approximately 41% came from industry and 31% from power plants. However, the synchronous analysis of the hourly concentrations, regional contributions, and wind vectors indicates that in the heaviest pollution periods the local emission sources play a more important role. The implications are that long-term control strategies should be based on regional-scale collaborations, and that emission abatement of local sources may be more effective in lowering the PM10 concentration levels on the heavy pollution days. Better air quality can be attained during the Olympics by placing effective emission controls on the local sources in Beijing and by controlling emissions from industry and power plants in the surrounding regions. 44 refs., 6 figs., 3 tabs.« less

A cooperative reduction model for regional air pollution control in China that considers adverse health effects and pollutant reduction costs.

PubMed

Xie, Yujing; Zhao, Laijun; Xue, Jian; Hu, Qingmi; Xu, Xiang; Wang, Hongbo

2016-12-15

How to effectively control severe regional air pollution has become a focus of global concern recently. The non-cooperative reduction model (NCRM) is still the main air pollution control pattern in China, but it is both ineffective and costly, because each province must independently fight air pollution. Thus, we proposed a cooperative reduction model (CRM), with the goal of maximizing the reduction in adverse health effects (AHEs) at the lowest cost by encouraging neighboring areas to jointly control air pollution. CRM has two parts: a model of optimal pollutant removal rates using two optimization objectives (maximizing the reduction in AHEs and minimizing pollutant reduction cost) while meeting the regional pollution control targets set by the central government, and a model that allocates the cooperation benefits (i.e., health improvement and cost reduction) among the participants according to their contributions using the Shapley value method. We applied CRM to the case of sulfur dioxide (SO 2 ) reduction in Yangtze River Delta region. Based on data from 2003 to 2013, and using mortality due to respiratory and cardiovascular diseases as the health endpoints, CRM saves 437 more lives than NCRM, amounting to 12.1% of the reduction under NCRM. CRM also reduced costs by US $65.8×10 6 compared with NCRM, which is 5.2% of the total cost of NCRM. Thus, CRM performs significantly better than NCRM. Each province obtains significant benefits from cooperation, which can motivate them to actively cooperate in the long term. A sensitivity analysis was performed to quantify the effects of parameter values on the cooperation benefits. Results shown that the CRM is not sensitive to the changes in each province's pollutant carrying capacity and the minimum pollutant removal capacity, but sensitive to the maximum pollutant reduction capacity. Moreover, higher cooperation benefits will be generated when a province's maximum pollutant reduction capacity increases. Copyright © 2016 Elsevier B.V. All rights reserved.

A longitudinal study of mortality and air pollution for São Paulo, Brazil.

PubMed

Botter, Denise A; Jørgensen, Bent; Peres, Antonieta A Q

2002-09-01

We study the effects of various air-pollution variables on the daily death counts for people over 65 years in São Paulo, Brazil, from 1991 to 1993, controlling for meteorological variables. We use a state space model where the air-pollution variables enter via the latent process, and the meteorological variables via the observation equation. The latent process represents the potential mortality due to air pollution, and is estimated by Kalman filter techniques. The effect of air pollution on mortality is found to be a function of the variation in the sulphur dioxide level for the previous 3 days, whereas the other air-pollution variables (total suspended particulates, nitrogen dioxide, carbon monoxide, ozone) are not significant when sulphur dioxide is in the equation. There are significant effects of humidity and up to lag 3 of temperature, and a significant seasonal variation.

Polluted Morality: Air Pollution Predicts Criminal Activity and Unethical Behavior.

PubMed

Lu, Jackson G; Lee, Julia J; Gino, Francesca; Galinsky, Adam D

2018-03-01

Air pollution is a serious problem that affects billions of people globally. Although the environmental and health costs of air pollution are well known, the present research investigates its ethical costs. We propose that air pollution can increase criminal and unethical behavior by increasing anxiety. Analyses of a 9-year panel of 9,360 U.S. cities found that air pollution predicted six major categories of crime; these analyses accounted for a comprehensive set of control variables (e.g., city and year fixed effects, population, law enforcement) and survived various robustness checks (e.g., balanced panel, nonparametric bootstrapped standard errors). Three subsequent experiments involving American and Indian participants established the causal effect of psychologically experiencing a polluted (vs. clean) environment on unethical behavior. Consistent with our theoretical perspective, results revealed that anxiety mediated this effect. Air pollution not only corrupts people's health, but also can contaminate their morality.

Flight Simulator Platform Motion and Air Transport Pilot Training

NASA Technical Reports Server (NTRS)

Lee, Alfred T.; Bussolari, Steven R.

1989-01-01

The influence of flight simulator platform motion on pilot training and performance was examined In two studies utilizing a B-727-200 aircraft simulator. The simulator, located at Ames Research Center, Is certified by the FAA for upgrade and transition training in air carrier operations. Subjective ratings and objective performance of experienced B-727 pilots did not reveal any reliable effects of wide variations In platform motion de- sign. Motion platform variations did, however, affect the acquisition of control skill by pilots with no prior heavy aircraft flying experience. The effect was limited to pitch attitude control inputs during the early phase of landing training. Implications for the definition of platform motion requirements in air transport pilot training are discussed.

Control of asthma triggers in indoor air with air cleaners: a modeling analysis.

PubMed

Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; Macintosh, David L

2008-08-06

Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30-55% lower cat allergen levels, 90-99% lower risk of respiratory infection through the inhalation route of exposure, 90-98% lower environmental tobacco smoke (ETS) levels, and 50-75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice.

Control of asthma triggers in indoor air with air cleaners: a modeling analysis

PubMed Central

Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; MacIntosh, David L

2008-01-01

Background Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. Methods We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Results Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30–55% lower cat allergen levels, 90–99% lower risk of respiratory infection through the inhalation route of exposure, 90–98% lower environmental tobacco smoke (ETS) levels, and 50–75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. Conclusion These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice. PMID:18684328

Effects-Based Operations: Air Power as the Sole Military Instrument of Power, Has it Matured Enough?

DTIC Science & Technology

2006-04-01

use the current term, but they all tend to favor control of the enemy through EBO rather than physical destruction for its own sake. Operation Allied...would not approve of any attacks against Belgrade’s electrical power grid that would physically destroy it.56 By focusing on the desired effect, US...perspectives on how to orchestrate the air campaign in OEF. CENTCOM had an attrition-based approach and wanted air power to physically destroy all

The effect of relative humidity of inhaled air on acoustic parameters of voice in normal subjects.

PubMed

Hemler, R J; Wieneke, G H; Dejonckere, P H

1997-09-01

The hypothesis that relative humidity (RH) of air exerts an effect on voice has been widely accepted. The aim of this study has been to assess whether this can be demonstrated. Eight healthy subjects inhaled during ten minutes three different air conditions: dry, standard room, and humidified air. After inhalation, the subjects produced repeatedly a sustained /a/ of controlled pitch and loudness, which was analyzed for perturbation and noise-to-harmonic parameters. Perturbation measures increased after inhalation of dry air. No significant differences existed between standard and humidified air. No significant difference in the noise-to-harmonic ratio was found among the three conditions. We conclude that the human voice is very sensitive to decreases in RH of inhaled air, because even after a short provocation with dry air, a significant increase in perturbation measures was found.

Air pollution, avoidance behaviour and children's respiratory health: evidence from England.

PubMed

Janke, Katharina

2014-12-01

Despite progress in air pollution control, concerns remain over the health impact of poor air quality. Governments increasingly issue air quality information to enable vulnerable groups to avoid exposure. Avoidance behaviour potentially biases estimates of the health effects of air pollutants. But avoidance behaviour imposes a cost on individuals and therefore may not be taken in all circumstances. This paper exploits panel data at the English local authority level to estimate the relationship between children's daily hospital emergency admissions for respiratory diseases and common air pollutants, while allowing for avoidance behaviour in response to air pollution warnings. A 1% increase in nitrogen dioxide or ozone concentrations increases hospital admissions by 0.1%. For the subset of asthma admissions - where avoidance is less costly - there is evidence of avoidance behaviour. Ignoring avoidance behaviour, however, does not result in statistically significant underestimation of the health effect of air pollution. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of Automation Types on Air Traffic Controller Situation Awareness and Performance

NASA Technical Reports Server (NTRS)

Sethumadhavan, A.

2009-01-01

The Joint Planning and Development Office has proposed the introduction of automated systems to help air traffic controllers handle the increasing volume of air traffic in the next two decades (JPDO, 2007). Because fully automated systems leave operators out of the decision-making loop (e.g., Billings, 1991), it is important to determine the right level and type of automation that will keep air traffic controllers in the loop. This study examined the differences in the situation awareness (SA) and collision detection performance of individuals when they worked with information acquisition, information analysis, decision and action selection and action implementation automation to control air traffic (Parasuraman, Sheridan, & Wickens, 2000). When the automation was unreliable, the time taken to detect an upcoming collision was significantly longer for all the automation types compared with the information acquisition automation. This poor performance following automation failure was mediated by SA, with lower SA yielding poor performance. Thus, the costs associated with automation failure are greater when automation is applied to higher order stages of information processing. Results have practical implications for automation design and development of SA training programs.

Complex Adaptive Systems: The Theater Air Control System in Desert Storm

DTIC Science & Technology

2014-05-22

insight into leverage points of effective and ineffective adaptation of the TACS. Successful adaptation indicates that increased variety or diversity of...encourages innovation and diversity of ideas. 15. SUBJECT TERMS Theater Air Control System, TACS, Complex Adaptive Systems, Adaptation, Desert Storm...increased variety or diversity of agents and purposeful behaviors are beneficial to overcoming complexity. Leaders play a key role in creating an

Spectral tuning of optical coupling between air-mode nanobeam cavities and individual carbon nanotubes

NASA Astrophysics Data System (ADS)

Machiya, H.; Uda, T.; Ishii, A.; Kato, Y. K.

2018-01-01

We demonstrate control over optical coupling between air-suspended carbon nanotubes and air-mode nanobeam cavities by spectral tuning. Taking advantage of the large dielectric screening effects caused by adsorbed molecules, laser heating is used to blueshift the nanotube photoluminescence. A significant increase in the cavity peak is observed when the nanotube emission is brought into resonance, and the spontaneous emission enhancement is estimated from the photoluminescence spectra. We find that the enhancement shows good correlation with the spectral overlap of the nanotube emission and the cavity peak. Our technique offers a convenient method for controlling the optical coupling of air-suspended nanotubes to photonic structures.

Modeling the effects of high-G stress on pilots in a tracking task

NASA Technical Reports Server (NTRS)

Korn, J.; Kleinman, D. L.

1978-01-01

Air-to-air tracking experiments were conducted at the Aerospace Medical Research Laboratories using both fixed and moving base dynamic environment simulators. The obtained data, which includes longitudinal error of a simulated air-to-air tracking task as well as other auxiliary variables, was analyzed using an ensemble averaging method. In conjunction with these experiments, the optimal control model is applied to model a human operator under high-G stress.

Simulating Human Cognition in the Domain of Air Traffic Control

NASA Technical Reports Server (NTRS)

Freed, Michael; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

1995-01-01

Experiments intended to assess performance in human-machine interactions are often prohibitively expensive, unethical or otherwise impractical to run. Approximations of experimental results can be obtained, in principle, by simulating the behavior of subjects using computer models of human mental behavior. Computer simulation technology has been developed for this purpose. Our goal is to produce a cognitive model suitable to guide the simulation machinery and enable it to closely approximate a human subject's performance in experimental conditions. The described model is designed to simulate a variety of cognitive behaviors involved in routine air traffic control. As the model is elaborated, our ability to predict the effects of novel circumstances on controller error rates and other performance characteristics should increase. This will enable the system to project the impact of proposed changes to air traffic control procedures and equipment on controller performance.

76 FR 39357 - Revisions to the California State Implementation Plan, Imperial County Air Pollution Control...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

... the California State Implementation Plan, Imperial County Air Pollution Control District, Kern County Air Pollution Control District, and Ventura County Air Pollution Control District AGENCY... the Imperial County Air Pollution Control District (ICAPCD), Kern County Air Pollution Control...

Interactions Between Dyspnea and the Brain Processing of Nociceptive Stimuli: Experimental Air Hunger Attenuates Laser-Evoked Brain Potentials in Humans.

PubMed

Dangers, Laurence; Laviolette, Louis; Similowski, Thomas; Morélot-Panzini, Capucine

2015-01-01

Dyspnea and pain share several characteristics and certain neural networks and interact with each other. Dyspnea-pain counter-irritation consists of attenuation of preexisting pain by intercurrent dyspnea and has been shown to have neurophysiological correlates in the form of inhibition of the nociceptive spinal reflex RIII and laser-evoked potentials (LEPs). Experimentally induced exertional dyspnea inhibits RIII and LEPs, while "air hunger" dyspnea does not inhibit RIII despite its documented analgesic effects. We hypothesized that air hunger may act centrally and inhibit LEPs. LEPs were obtained in 12 healthy volunteers (age: 21-29) during spontaneous breathing (FB), ventilator-controlled breathing (VC) tailored to FB, after inducing air hunger by increasing the inspired fraction of carbon dioxide -FiCO2- (VCCO2), and during ventilator-controlled breathing recovery (VCR). VCCO2 induced intense dyspnea (visual analog scale = 63% ± 6% of full scale, p < 0.001 vs. VC), predominantly of the air hunger type. VC alone reduced the amplitude of the N2-P2 component of LEPs (Δ = 24.0% ± 21.1%, p < 0.05, effect-size = 0.74) predominantly through a reduction in P2, and the amplitude of this inhibition was further reduced by inducting air hunger (Δ = 22.6% ± 17.9%, p < 0.05, effect-size = 0.53), predominantly through a reduction in N2. Somatosensory-evoked potentials (SEPs) were not affected by VC or VCCO2, suggesting that the observed effects are specific to pain transmission. We conclude that air hunger interferes with the cortical mechanisms responsible for the cortical response to painful laser skin stimulation, which provides a neurophysiological substrate to the central nature of its otherwise documented analgesic effects.

Traffic-Related Air Pollution and Parkinson’s Disease in Denmark: A Case–Control Study

PubMed Central

Ritz, Beate; Lee, Pei-Chen; Hansen, Johnni; Lassen, Christina Funch; Ketzel, Matthias; Sørensen, Mette; Raaschou-Nielsen, Ole

2015-01-01

Background Very little is currently known about air pollutants’ adverse effects on neurodegenerative diseases even though recent studies have linked particulate exposures to brain pathologies associated with Parkinson’s and Alzheimer’s disease. Objective In the present study, we investigated long-term exposure to traffic-related air pollution and Parkinson’s disease. Methods In a case–control study of 1,696 Parkinson’s disease (PD) patients identified from Danish hospital registries and diagnosed 1996–2009 and 1,800 population controls matched by sex and year of birth, we assessed long-term traffic-related air pollutant exposures (represented by nitrogen dioxide; NO2) from a dispersion model, using residential addresses from 1971 to the date of diagnosis or first cardinal symptom for cases and the corresponding index date for their matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated with logistic regression, adjusting for matching factors and potential confounders. Results We found ambient air pollution from traffic sources to be associated with risk of PD, with a 9% higher risk (95% CI: 3, 16.0%) per interquartile range increase (2.97 μg/m3) in modeled NO2. For participants living for ≥ 20 years in the capital city, ORs were larger (OR = 1.21; 95% CI: 1.11, 1.31) than in provincial towns (OR = 1.10; 95% CI: 0.97, 1.26), whereas there was no association among rural residents. Conclusions Our findings raise concerns about potential effects of air pollution from traffic and other sources on the risk of PD, particularly in populations with high or increasing exposures. Citation Ritz B, Lee PC, Hansen J, Funch Lassen C, Ketzel M, Sørensen M, Raaschou-Nielsen O. 2016. Traffic-related air pollution and Parkinson’s disease in Denmark: a case–control study. Environ Health Perspect 124:351–356; http://dx.doi.org/10.1289/ehp.1409313 PMID:26151951

Air quality assessment in Delhi: before and after CNG as fuel.

PubMed

Chelani, Asha B; Devotta, Sukumar

2007-02-01

A number of policy measures have been activated in India in order to control the levels of air pollutants such as particulate matter, sulphur dioxide (SO(2)) and nitrogen dioxide (NO(2)). Delhi, which is one of the most polluted cities in the world, is also going through the implementation phase of the control policies. Ambient air quality data monitored during 2000 to 2003, at 10 sites in Delhi, were analyzed to assess the impact of implementation of these measures, specifically fuel change in vehicles. This paper presents the impact of policy measures on ambient air quality levels and also the source apportionment. CO and NO(2) concentration levels in ambient air are found to be associated with the mobile sources. The temporal variation of air quality data shows the significant effect of shift to CNG (Compressed Natural Gas) in vehicles.

Prediction of Traffic Complexity and Controller Workload in Mixed Equipage NextGen Environments

NASA Technical Reports Server (NTRS)

Lee, Paul U.; Prevot, Thomas

2012-01-01

Controller workload is a key factor in limiting en route air traffic capacity. Past efforts to quantify and predict workload have resulted in identifying objective metrics that correlate well with subjective workload ratings during current air traffic control operations. Although these metrics provide a reasonable statistical fit to existing data, they do not provide a good mechanism for estimating controller workload for future air traffic concepts and environments that make different assumptions about automation, enabling technologies, and controller tasks. One such future environment is characterized by en route airspace with a mixture of aircraft equipped with and without Data Communications (Data Comm). In this environment, aircraft with Data Comm will impact controller workload less than aircraft requiring voice communication, altering the close correlation between aircraft count and controller workload that exists in current air traffic operations. This paper outlines a new trajectory-based complexity (TBX) calculation that was presented to controllers during a human-in-the-loop simulation. The results showed that TBX accurately estimated the workload in a mixed Data Comm equipage environment and the resulting complexity values were understood and readily interpreted by the controllers. The complexity was represented as a "modified aircraft account" that weighted different complexity factors and summed them in such a way that the controllers could effectively treat them as aircraft count. The factors were also relatively easy to tune without an extensive data set. The results showed that the TBX approach is well suited for presenting traffic complexity in future air traffic environments.

Upper-Room Ultraviolet Light and Negative Air Ionization to Prevent Tuberculosis Transmission

PubMed Central

Escombe, A. Roderick; Moore, David A. J; Gilman, Robert H; Navincopa, Marcos; Ticona, Eduardo; Mitchell, Bailey; Noakes, Catherine; Martínez, Carlos; Sheen, Patricia; Ramirez, Rocio; Quino, Willi; Gonzalez, Armando; Friedland, Jon S; Evans, Carlton A

2009-01-01

Background Institutional tuberculosis (TB) transmission is an important public health problem highlighted by the HIV/AIDS pandemic and the emergence of multidrug- and extensively drug-resistant TB. Effective TB infection control measures are urgently needed. We evaluated the efficacy of upper-room ultraviolet (UV) lights and negative air ionization for preventing airborne TB transmission using a guinea pig air-sampling model to measure the TB infectiousness of ward air. Methods and Findings For 535 consecutive days, exhaust air from an HIV-TB ward in Lima, Perú, was passed through three guinea pig air-sampling enclosures each housing approximately 150 guinea pigs, using a 2-d cycle. On UV-off days, ward air passed in parallel through a control animal enclosure and a similar enclosure containing negative ionizers. On UV-on days, UV lights and mixing fans were turned on in the ward, and a third animal enclosure alone received ward air. TB infection in guinea pigs was defined by monthly tuberculin skin tests. All guinea pigs underwent autopsy to test for TB disease, defined by characteristic autopsy changes or by the culture of Mycobacterium tuberculosis from organs. 35% (106/304) of guinea pigs in the control group developed TB infection, and this was reduced to 14% (43/303) by ionizers, and to 9.5% (29/307) by UV lights (both p < 0.0001 compared with the control group). TB disease was confirmed in 8.6% (26/304) of control group animals, and this was reduced to 4.3% (13/303) by ionizers, and to 3.6% (11/307) by UV lights (both p < 0.03 compared with the control group). Time-to-event analysis demonstrated that TB infection was prevented by ionizers (log-rank 27; p < 0.0001) and by UV lights (log-rank 46; p < 0.0001). Time-to-event analysis also demonstrated that TB disease was prevented by ionizers (log-rank 3.7; p = 0.055) and by UV lights (log-rank 5.4; p = 0.02). An alternative analysis using an airborne infection model demonstrated that ionizers prevented 60% of TB infection and 51% of TB disease, and that UV lights prevented 70% of TB infection and 54% of TB disease. In all analysis strategies, UV lights tended to be more protective than ionizers. Conclusions Upper-room UV lights and negative air ionization each prevented most airborne TB transmission detectable by guinea pig air sampling. Provided there is adequate mixing of room air, upper-room UV light is an effective, low-cost intervention for use in TB infection control in high-risk clinical settings. PMID:19296717

[Time-series analysis on effect of air pollution on stroke mortality in Tianjin, China].

PubMed

Wang, De-zheng; Gu, Qing; Jiang, Guo-hong; Yang, De-yi; Zhang, Hui; Song, Gui-de; Zhang, Ying

2012-12-01

To investigate the effect of air pollution on stroke mortality in Tianjin, China, and to provide basis for stroke control and prevention. Total data of mortality surveillance were collected by Tianjin Centers for Disease Control and Prevention. Meteorological data and atmospheric pollution data were from Tianjin Meteorological Bureau and Tianjin Environmental Monitoring Center, respectively. Generalized additive Poisson regression model was used in time-series analysis on the relationship between air pollution and stroke mortality in Tianjin. Single-pollutant analysis and multi-pollutant analysis were performed after adjustment for confounding factors such as meteorological factors, long-term trend of death, "days of the week" effect and population. The crude death rates of stroke in Tianjin were from 136.67 in 2001 to 160.01/100000 in 2009, with an escalating trend (P = 0.000), while the standardized mortality ratios of stroke in Tianjin were from 138.36 to 99.14/100000, with a declining trend (P = 0.000). An increase of 10 µg/m³ in daily average concentrations of atmospheric SO₂, NO₂ and PM₁₀ led to 1.0105 (95%CI: 1.0060 ∼ 1.0153), 1.0197 (95%CI: 1.0149 ∼ 1.0246) and 1.0064 (95%CI: 1.0052 ∼ 1.0077), respectively, in relative risks of stroke mortality. SO₂ effect peaked after 1-day exposure, while NO₂ and PM₁₀ effects did within 1 day. Air pollution in Tianjin may increase the risk of stroke mortality in the population and induce acute onset of stroke. It is necessary to carry out air pollution control and allocate health resources rationally to reduce the hazard of stroke mortality.

Air-insufflated high-definition dacryoendoscopy yields significantly better image quality than conventional dacryoendoscopy.

PubMed

Sasaki, Tsugihisa; Sounou, Tsutomu; Tsuji, Hideki; Sugiyama, Kazuhisa

2017-01-01

To facilitate the analysis of lacrimal conditions, we utilized high-definition dacryoendoscopy (HDD) and undertook observations with a pressure-controlled air-insufflation system. We report the safety and performance of HDD. In this retrospective, non-randomized clinical trial, 46 patients (14 males and 32 females; age range 39-91 years; mean age ± SD 70.3±12.0 years) who had lacrimal disorders were examined with HDD and conventional dacryoendoscopy (CD). The high-definition dacryoendoscope had 15,000 picture element image fibers and an advanced objective lens. Its outer diameter was 0.9-1.2 mm. Air insufflation was controlled at 0-20 kPa with a digital manometer-based pressure-controlled air-insufflation system to evaluate the quality of the image. The HDD had an air/saline irrigation channel between the outer sheath (outer diameter =1.2 mm) and the metal inner sheath of the endoscope. We used it and the CD in air, saline, and diluted milk saline with and without manual irrigation to quantitatively evaluate the effect of air pressure and saline irrigation on image quality. In vivo, the most significant improvement in image quality was demonstrated with air-insufflated (5-15 kPa) HDD, as compared with saline-irrigated HDD and saline-irrigated CD. No emphysema or damage was noted under observation with HDD. In vitro, no significant difference was demonstrated between air-insufflated HDD and saline-irrigated HDD. In vitro, the image quality of air-insufflated HDD was significantly improved as compared with that of saline-irrigated CD. Pressure-controlled (5-15 kPa) air-insufflated HDD is safe, and yields significantly better image quality than CD and saline-irrigated HDD.

Bayesian Analysis of a Reduced-Form Air Quality Model

EPA Science Inventory

Numerical air quality models are being used for assessing emission control strategies for improving ambient pollution levels across the globe. This paper applies probabilistic modeling to evaluate the effectiveness of emission reduction scenarios aimed at lowering ground-level oz...

Human health effects of air pollution.

PubMed Central

Folinsbee, L J

1993-01-01

Over the past three or four decades, there have been important advances in the understanding of the actions, exposure-response characteristics, and mechanisms of action of many common air pollutants. A multidisciplinary approach using epidemiology, animal toxicology, and controlled human exposure studies has contributed to the database. This review will emphasize studies of humans but will also draw on findings from the other disciplines. Air pollutants have been shown to cause responses ranging from reversible changes in respiratory symptoms and lung function, changes in airway reactivity and inflammation, structural remodeling of pulmonary airways, and impairment of pulmonary host defenses, to increased respiratory morbidity and mortality. Quantitative and qualitative understanding of the effects of a small group of air pollutants has advanced considerably, but the understanding is by no means complete, and the breadth of effects of all air pollutants is only partially understood. PMID:8354181

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

ERIC Educational Resources Information Center

Mullins, Cecil J.; And Others

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

Air pollution impacts on forests in changing climate

Treesearch

M. Lorenz; N. Clarke; E. Paoletti; A. Bytnerowicz; N. Grulke; N. Lukina; H. Sase; J. Staelens

2010-01-01

Growing awareness of air pollution effects on forests has, from the early 1980s on, led to intensive forest damage research and monitoring. This has fostered air pollution control, especially in Europe and North America, and to a smaller extent also in other parts of the world. At several forest sites in these regions, there are first indications of a recovery of...

Methodology for Examining Effects of Arms Control Reduction on Tactical Air Forces. An Example from Conventional Forces in Europe (CFE) Treaty Analysis

DTIC Science & Technology

1993-01-01

H. Wegner for developing the tactical air and ground force databases and producing the campaign results. Thanks are also due to Group Captain Michael ... Jackson , RAF, for developing the evaluation criteria for NATO’s tactical air force reductions during his stay at RAND. -xi. CONTENTS PREFACE

The effect of sodium hyaluronate-carboxymethyl cellulose membrane in the prevention of parenchymal air leaks: an experimental and manometric study in rats.

PubMed

Büyükkale, Songül; Çıtak, Necati; İşgörücü, Özgür; Sayar, Adnan

2017-12-01

We aimed to examine effectiveness of sodium hyaluronate-carboxymethly cellulose (NaH/CMC) for sealing pulmonary air leaks during postoperative period. The study was conducted in 16 male Sprague-Dawley rats. A linear insicion (length= 0.2 cm, depth= 0.1 cm) to the lung parenchyma on the inflated by a cutter was made. The animals were randomly divided; the control group (n= 8) and NaH/CMC-treated group (the study group, n= 8). Control group was left for physiologic healing while a NaH/CMC membrane was applied over the the incisional area in the study group. Then the pressure point where the air leakage observed was noted. No polymorphonucleer leucocytes (PMNL) infiltration was detected in control group, whereas PMNL infiltration was 0.38 ± 0.5 cell per 100 high field in study group (p= 0.234). The degree of macrophage, lymphocyte infiltration and the mean fibroblast count were found to be higher in study group compared with control group (p= 0.007, p= 0.02, p= 0.05, respectively). The mean pressure value for air leak to occur in the control group was 43.50 ± 9.55 mmHg whereas it was 73.75 ± 16.68 mmHg in the study group (p< 0.001). The data revealed that bioabsorbable NaH/CMC membrane accelerates healing with preserving the expansile character of lung parenchyma even in high ventilation pressures. However, further studies are required to assess the prevent impact of the pulmonary air-leak for NaH/CMC membrane.

Positioning and Microvibration Control by Electromagnets of an Air Spring Vibration Isolation System

NASA Technical Reports Server (NTRS)

Watanabe, Katsuhide; Cui, Weimin; Haga, Takahide; Kanemitsu, Yoichi; Yano, Kenichi

1996-01-01

Active positioning and microvibration control has been attempted by electromagnets equipped in a bellows-type, air-spring vibration isolation system. Performance tests have been carried out to study the effects. The main components of the system's isolation table were four electromagnetic actuators and controllers. The vibration isolation table was also equipped with six acceleration sensors for detecting microvibration of the table. The electromagnetic actuators were equipped with bellows-type air springs for passive support of the weight of the item placed on the table, with electromagnets for active positioning, as well as for microvibration control, and relative displacement sensors. The controller constituted a relative feedback system for positioning control and an absolute feedback system for vibration isolation control. In the performance test, a 1,490 kg load (net weight of 1,820 kg) was placed on the vibration isolation table, and both the positioning and microvibration control were carried out electromagnetically. Test results revealed that the vibration transmission was reduced by 95%.

Chronic effects of air pollution on respiratory health in Southern California children: findings from the Southern California Children’s Health Study

PubMed Central

Chen, Zhanghua; Salam, Muhammad T.; Eckel, Sandrah P.; Breton, Carrie V.

2015-01-01

Outdoor air pollution is one of the leading contributors to adverse respiratory health outcomes in urban areas around the world. Children are highly sensitive to the adverse effects of air pollution due to their rapidly growing lungs, incomplete immune and metabolic functions, patterns of ventilation and high levels of outdoor activity. The Children’s Health Study (CHS) is a continuing series of longitudinal studies that first began in 1993 and has focused on demonstrating the chronic impacts of air pollution on respiratory illnesses from early childhood through adolescence. A large body of evidence from the CHS has documented that exposures to both regional ambient air and traffic-related pollutants are associated with increased asthma prevalence, new-onset asthma, risk of bronchitis and wheezing, deficits of lung function growth, and airway inflammation. These associations may be modulated by key genes involved in oxidative-nitrosative stress pathways via gene-environment interactions. Despite successful efforts to reduce pollution over the past 40 years, air pollution at the current levels still brings many challenges to public health. To further ameliorate adverse health effects attributable to air pollution, many more toxic pollutants may require regulation and control of motor vehicle emissions and other combustion sources may need to be strengthened. Individual interventions based on personal susceptibility may be needed to protect children’s health while control measures are being implemented. PMID:25694817

Institutional Tuberculosis Transmission. Controlled Trial of Upper Room Ultraviolet Air Disinfection: A Basis for New Dosing Guidelines.

PubMed

Mphaphlele, Matsie; Dharmadhikari, Ashwin S; Jensen, Paul A; Rudnick, Stephen N; van Reenen, Tobias H; Pagano, Marcello A; Leuschner, Wilhelm; Sears, Tim A; Milonova, Sonya P; van der Walt, Martie; Stoltz, Anton C; Weyer, Karin; Nardell, Edward A

2015-08-15

Transmission is driving the global tuberculosis epidemic, especially in congregate settings. Worldwide, natural ventilation is the most common means of air disinfection, but it is inherently unreliable and of limited use in cold climates. Upper room germicidal ultraviolet (UV) air disinfection with air mixing has been shown to be highly effective, but improved evidence-based dosing guidelines are needed. To test the efficacy of upper room germicidal air disinfection with air mixing to reduce tuberculosis transmission under real hospital conditions, and to define the application parameters responsible as a basis for proposed new dosing guidelines. Over an exposure period of 7 months, 90 guinea pigs breathed only untreated exhaust ward air, and another 90 guinea pigs breathed only air from the same six-bed tuberculosis ward on alternate days when upper room germicidal air disinfection was turned on throughout the ward. The tuberculin skin test conversion rates (>6 mm) of the two chambers were compared. The hazard ratio for guinea pigs in the control chamber converting their skin test to positive was 4.9 (95% confidence interval, 2.8-8.6), with an efficacy of approximately 80%. Upper room germicidal UV air disinfection with air mixing was highly effective in reducing tuberculosis transmission under hospital conditions. These data support using either a total fixture output (rather than electrical or UV lamp wattage) of 15-20 mW/m(3) total room volume, or an average whole-room UV irradiance (fluence rate) of 5-7 μW/cm(2), calculated by a lighting computer-assisted design program modified for UV use.

Application of local exhaust ventilation system and integrated collectors for control of air pollutants in mining company.

PubMed

Ghorbani Shahna, Farshid; Bahrami, Abdulrahman; Farasati, Farhad

2012-01-01

Local exhaust ventilation (LEV) systems and integrated collectors were designed and implemented in a mining company in order to control emitted air pollutant from furnaces. The LEV was designed for capture and transition of air pollutants emitted from furnaces to the integrated collectors. The integrated collectors including four high efficiency Stairmand model cyclones for control of particulate matter, a venturi scrubber for control of the fine particles, SO(2) and a part of H(2)S to follow them, and a packed scrubber for treatment of the residual H(2)S and SO(2) were designed. Pollutants concentration were measured to determine system effectiveness. The results showed that the effectiveness of LEV for reducing workplace pollution is 91.83%, 96.32% and 83.67% for dust, SO(2) and H(2)S, respectively. Average removal efficiency of particles by combination of cyclone and venturi scrubber was 98.72%. Average removal efficiency of SO(2) and H(2)S were 95.85% and 47.13% for the venturi scrubber and 68.45% and 92.7% for the packed bed scrubber. The average removal efficiency of SO(2) and H(2)S were increased to 99.1% and 95.95% by the combination of venturi and packed bed scrubbers. According to the results, integrated collectors are a good air pollution control option for industries with economic constraints and ancient technologies.

Environmental control implications of generating electric power from coal. 1977 technology status report. Appendix D. Assessment of NO/sub x/ control technology for coal fired utility boilers. [Low-excess-air, staged combustion, flu gas recirculation and burner design

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

Not Available

1977-12-01

An NOx control technology assessment study was conducted to examine the effectiveness of low-excess-air firing, staged combustion, flue gas recirculation, and current burner/boiler designs as applied to coal-fired utility boilers. Significant variations in NOx emissions exist with boiler type, firing method, and coal type, but a relative comparison of emissions control performance, cost, and operational considerations is presented for each method. The study emphasized the numerous operational factors that are of major importance to the user in selecting and implementing a combustion modification technique. Staged combustion and low-excess-air operation were identified as the most cost-effective methods for existing units. Closemore » control of local air/fuel ratios and rigorous combustion equipment maintenance are essential to the success of both methods. Flue gas recirculation is relatively ineffective and has the added concern of tube erosion. More research is needed to resolve potential corrosion concerns with low-NOx operating modes. Low-NOx burners in conjunction with a compartmentalized windbox are capable of meeting a 0.6-lb/million Btu emission level on new units. Advanced burner designs are being developed to meet research emission goals of approximately 0.25 lb/MBtu.« less

The Effects of Energy Drinks on Cognitive Ability

NASA Astrophysics Data System (ADS)

Lucas, Marlon R.

Fatigue problems have been widespread in the air traffic control industry; in past years a common practice among air traffic controllers has been to consume highly caffeinated beverages to maintain awareness and thwart sleep deprivation. This study sought to examine what impact the consumption of an energy drink had on Air Traffic Control Collegiate Training Initiative students at Middle Tennessee State University to solve Air Traffic Selection and Training Battery Applied Math type test problems. Participants consumed a Red Bull energy drink or a placebo and then were asked to complete speed, time, distance, and rate of climb and descent rates questions in addition to answering questions regarding their perception of energy drinks. An appropriate statistical analysis was applied to compare scores of participants. The experimental group which received the energy drink averaged slightly lower (M=77.27, SD=19.79) than the control group, which consumed the placebo beverage (M=81.5, SD=19.01), but this difference was not statistically significant.

Effects of water-contaminated air on blowoff limits of opposed jet hydrogen-air diffusion flames

NASA Technical Reports Server (NTRS)

Pellett, Gerald L.; Jentzen, Marilyn E.; Wilson, Lloyd G.; Northam, G. Burton

1988-01-01

The effects of water-contaminated air on the extinction and flame restoration of the central portion of N2-diluted H2 versus air counterflow diffusion flames are investigated using a coaxial tubular opposed jet burner. The results show that the replacement of N2 contaminant in air by water on a mole for mole basis decreases the maximum sustainable H2 mass flow, just prior to extinction, of the flame. This result contrasts strongly with the analogous substitution of water for N2 in a relatively hot premixed H2-O2-N2 flame, which was shown by Koroll and Mulpuru (1986) to lead to a significant, kinetically controlled increase in laminar burning velocity.

Department of Defense Air Traffic Control and Airspace Systems Interface with the National Airspace System

DTIC Science & Technology

1990-03-30

systems on the DoD in terms of safety and operational- effectiveness and probable impacts on specific Air Force mission requirements. The report does... Systems ................................. 2-21 2.1.3 Flight Service and Weather Systems .......................... 2-22 2.1.3.1 Flight Service Automation...2-41 2.2.2 Terminal Control and Landing Systems .. ....................... 2-44 2.2.3 Flight Information and Weather Systems

Influence of harvest residues and vegetation on microsite soil and air temperatures in a young conifer plantation.

Treesearch

W.D. Devine; C.A. Harrington

2007-01-01

This study examines the effects of bole-only harvesting with and without vegetation control (BO+VC; BO-VC) and total-tree harvesting plus removal of legacy woody debris with vegetation control (TTP+VC) on microsite soil and air temperatures in a young Douglas-fir plantation. Mean soil temperature and the diurnal range in soil temperature during the growing season...

Co-control of local air pollutants and CO2 in the Chinese iron and steel industry.

PubMed

Mao, Xianqiang; Zeng, An; Hu, Tao; Zhou, Ji; Xing, Youkai; Liu, Shengqiang

2013-01-01

The present study proposes an integrated multipollutant cocontrol strategy framework in the context of the Chinese iron and steel industry. The unit cost of pollutant reduction (UCPR) was used to examine the cost-effectiveness of each emission reduction measure. The marginal abatement cost (MAC) curves for SO2, NOx, PM2.5, and CO2 were drawn based on the UCPR and the abatement potential. Air pollutant equivalence (APeq) captures the nature of the damage value-weights of various air pollutants and acts as uniformization multiple air pollutants index. Single pollutant abatement routes designed in accordance with the corresponding reduction targets revealed that the cocontrol strategy has promising potential. Moreover, with the same reduction cost limitations as the single pollutant abatement routes, the multipollutant cocontrol routes are able to obtain more desirable pollution reduction and health benefits. Co-control strategy generally shows cost-effective advantage over single-pollutant abatement strategy. The results are robust to changing parameters according to sensitivity analysis. Co-control strategy would be an important step to achieve energy/carbon intensity targets and pollution control targets in China. Though cocontrol strategy has got some traction in policy debates, there are barriers to integrate it into policy making in the near future in China.

Genotoxic effects following exposure to air pollution in street vendors from a high-traffic urban area.

PubMed

Domingues, Érica Prado; Silva, Guilherme Gomes; Oliveira, Andrei Barbassa; Mota, Lorrany Marins; Santos, Vanessa Santana Vieira; de Campos, Edimar Olegário; Pereira, Boscolli Barbosa

2018-03-14

Workers in several occupational environments are exposed to pollutants. Street vendors, for example, typically work in a high-traffic urban environment and are exposed to numerous air pollutants, including genotoxic substances emitted by motor vehicles. This study examined the genotoxic effects of exposure to air pollution. We conducted cytological analyses to assess frequencies of micronucleated (MN) and binucleated (BN) cells in a sample of exfoliated oral mucosa cells. We compared street vendors and control subjects in the city of Uberlândia, Minas Gerais, Brazil, and also collected quantitative information on exposure conditions of all test subjects, including concentrations of particulate matter. We found street vendors to exhibit higher frequencies of MN cells compared to the control group. We evaluated the effects of possible confounding variables on MN frequencies, namely the body mass index (BMI), age, as well as smoking and alcohol habits. Multiple linear regression analysis found no significant effects of any of those variables. Our results suggest that continued exposure to air pollution from traffic represents a major source of genotoxicity and raises concerns regarding disease prevention not only in street vendors but also other groups of people working in urban environments.

76 FR 39303 - Revisions to the California State Implementation Plan, Imperial County Air Pollution Control...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

... the California State Implementation Plan, Imperial County Air Pollution Control District, Kern County Air Pollution Control District, and Ventura County Air Pollution Control District AGENCY... approve revisions to the Imperial County Air Pollution Control District (ICAPCD), Kern County Air...

Control of gill ventilation and air-breathing in the bowfin amia calva

PubMed

Hedrick; Jones

1999-01-01

The purpose of this study was to investigate the roles of branchial and gas bladder reflex pathways in the control of gill ventilation and air-breathing in the bowfin Amia calva. We have previously determined that bowfin use two distinct air-breathing mechanisms to ventilate the gas bladder: type I air breaths are characterized by exhalation followed by inhalation, are stimulated by aquatic or aerial hypoxia and appear to regulate O2 gas exchange; type II air breaths are characterized by inhalation alone and possibly regulate gas bladder volume and buoyancy. In the present study, we test the hypotheses (1) that gill ventilation and type I air breaths are controlled by O2-sensitive chemoreceptors located in the branchial region, and (2) that type II air breaths are controlled by gas bladder mechanosensitive stretch receptors. Hypothesis 1 was tested by examining the effects of partial or complete branchial denervation of cranial nerves IX and X to the gill arches on gill ventilation frequency (fg) and the proportion of type I air breaths during normoxia and hypoxia; hypothesis II was tested by gas bladder inflation and deflation. Following complete bilateral branchial denervation, fg did not differ from that of sham-operated control fish; in addition, fg was not significantly affected by aquatic hypoxia in sham-operated or denervated fish. In sham-operated fish, aquatic hypoxia significantly increased overall air-breathing frequency (fab) and the percentage of type I breaths. In fish with complete IX-X branchial denervation, fab was also significantly increased during aquatic hypoxia, but there were equal percentages of type I and type II air breaths. Branchial denervation did not affect the frequency of type I air breaths during aquatic hypoxia. Gas bladder deflation via an indwelling catheter resulted in type II breaths almost exclusively; furthermore, fab was significantly correlated with the volume removed from the gas bladder, suggesting a volume-regulating function for type II air breaths. These results indicate that chronic (3-4 weeks) branchial denervation does not significantly affect fg or type I air-breathing responses to aquatic hypoxia. Because type I air-breathing responses to aquatic hypoxia persist after IX-X cranial nerve denervation, O2-sensitive chemoreceptors that regulate air-breathing may be carried in other afferent pathways, such as the pseudobranch. Gas bladder deflation reflexly stimulates type II breaths, suggesting that gas bladder volume-sensitive stretch receptors control this particular air-breathing mechanism. It is likely that type II air breaths function to regulate buoyancy when gas bladder volume declines during the inter-breath interval.

Cervical Spine Status of Pilots and Air-Controllers of Airborne Early Warning and Control Aircraft.

PubMed

Shin, Young Ho; Yun, Chul; Han, Andrew Hogyu

2017-05-01

Many countries have developed their own airborne early warning and control (AEW&C) systems for use in surveying their territorial sky in real time. However, a review of the literature suggests that no studies have been conducted to analyze the cervical spine of pilots and air-controllers of AEW&C aircraft. The study subjects were 80 pilots and air-controllers of AEW&C aircraft with a period of service of > 1 yr and had data on physical examinations, simple radiographs and functional scores of the axial skeleton, and questionnaires about lifestyle and working conditions. Information about physical characteristics and experience of neck pain were collected. Functional scores including the neck disability index and short-form 36-item health survey were obtained. Radiological measurements were performed for the C2-7 Cobb angle and degree of forward head posture. Of the 80 subjects, 33 (41.3%) had experienced neck pain and 63 (78.8%) had impaired cervical lordosis. The results of functional and radiological evaluations were not significantly different between pilots and air-controllers. In multivariate analysis, only the age was significantly related to the occurrence of impaired cervical lordosis. However, there were no significant factors related to the occurrence of neck pain. The results of this study suggest that the working environment of pilots and air-controllers of AEW&C aircraft has a negative effect on their cervical spine. Age seemed to be the most significant factor affecting the occurrence of impaired cervical lordosis in these subjects.Shin YH, Yun C, Han AH. Cervical spine status of pilots and air-controllers of airborne early warning and control aircraft. Aerosp Med Hum Perform. 2017; 88(5):476-480.

40 CFR 86.1709-99 - Exhaust emission standards for 1999 and later light light-duty trucks.

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE...+NOX emission control effectiveness during A/C-on operation when the vehicle is operated under... in control system NMHC+NOX effectiveness do occur as a result of such calibrations, the manufacturer...

40 CFR 86.1708-99 - Exhaust emission standards for 1999 and later light-duty vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY...+NOX emission control effectiveness during A/C-on operation when the vehicle is operated under... in control system NMHC+NOX effectiveness do occur as a result of such calibrations, the manufacturer...

40 CFR 86.1708-99 - Exhaust emission standards for 1999 and later light-duty vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY...+NOX emission control effectiveness during A/C-on operation when the vehicle is operated under... in control system NMHC+NOX effectiveness do occur as a result of such calibrations, the manufacturer...

40 CFR 86.1709-99 - Exhaust emission standards for 1999 and later light light-duty trucks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE...+NOX emission control effectiveness during A/C-on operation when the vehicle is operated under... in control system NMHC+NOX effectiveness do occur as a result of such calibrations, the manufacturer...

microRNA Regulation of DEP-induced Inflammation in Airway Epithelial Cells

EPA Science Inventory

Morbidity and mortality attributable to air pollution continues to be a growing problem worldwide. Despite several studies on the health effects of ambient air pollution, underlying molecular mechanisms of susceptibility and disease remain elusive. The epigenome controls gene exp...

PARTICLE SIZE DISTRIBUTIONS FOR AN OFFICE AEROSOL

EPA Science Inventory

The article discusses an evaluation of the effect of percent outdoor air supplied and occupation level on the particle size distributions and mass concentrations for a typical office building. (NOTE: As attention has become focused on indoor air pollution control, it has become i...

ASSESSMENT OF BIOFILTER MEDIA PARTICLE SIZES FOR REMOVING AMMONIA

USDA-ARS?s Scientific Manuscript database

With increased concerns over odor and gas emissions from livestock production facilities more efficient technologies of air pollution control are needed to mitigate the deleterious effects of air contaminants. Gas-phase biofilters for treating contaminant gases from poultry and livestock operations ...

Assessment of Biofilter Media Particle Sizes for Removing Ammonia

USDA-ARS?s Scientific Manuscript database

With increased concerns over odor and gas emissions from livestock production facilities more efficient technologies of air pollution control are needed to mitigate the deleterious effects of air contaminants. Gas-phase biofilters for treating contaminant gases from poultry and livestock operations ...

Method and apparatus for checking fire detectors

NASA Technical Reports Server (NTRS)

Clawson, G. T. (Inventor)

1974-01-01

A fire detector checking method and device are disclosed for nondestructively verifying the operation of installed fire detectors of the type which operate on the principle of detecting the rate of temperature rise of the ambient air to sound an alarm and/or which sound an alarm when the temperature of the ambient air reaches a preset level. The fire alarm checker uses the principle of effecting a controlled simulated alarm condition to ascertain wheather or not the detector will respond. The checker comprises a hand-held instrument employing a controlled heat source, e.g., an electric lamp having a variable input, for heating at a controlled rate an enclosed mass of air in a first compartment, which air mass is then disposed about the fire detector to be checked. A second compartment of the device houses an electronic circuit to sense and adjust the temperature level and heating rate of the heat source.

A Method to Quantify the Wind and Non-wind Contribution to Year-to-year Air Quality Variation and its Application in China

NASA Astrophysics Data System (ADS)

LI, Y.; Lau, A. K. H.; Wong, A.; Fung, J. C. H.

2017-12-01

Changes in emissions and wind are often identified as the two dominant factors contributing to year-to-year variations in the concentration of primary pollutants. However, because changes in wind and emissions are intertwined, it has been difficult to quantitatively differentiate their effects on air quality directly from observed data. In particular, if the annual mean concentration of pollutants is higher than the previous year, it is difficult to identify whether the deterioration in air quality is caused by wind blowing from more polluted regions or an increase in contributing emissions. In this paper, based on wind and pollution roses, we propose a method to differentiate the effects of wind and non-wind (e.g., emissions) changes using direct observation. An index (L) is first defined to quantify the validity of the linear decomposition. The method is then validated by idealized experiments, numerical experiments and a two-year observation dataset from an actual emissions control program. Finally, we demonstrate the proposed method by studying long-term PM10 variations in Hong Kong during 2000-2011. We find that for most of the period, the linear decomposition of the changes in annual PM10 is valid (up to 90% confidence) and is dominated by the change in non-wind effects (e.g., emissions), whereas the average absolute effect from the wind variability is about 20%. Sensitivity analyses also suggest that our method should work in any location as long as the observed wind and pollution data have sufficient duration and resolution to resolve the corresponding wind and pollution roses. The method is applied for estimating the control effectiveness of the intervention programs in the Shanghai Expo, the longest socioeconomic international event held in China. The results show that integrated effect of control policies taken for improving the air quality in Shanghai are significantly effective for PM10 reduction and also effective for SO2 reduction, whereas the traffic emission control are not effective for NO2 at urban stations, though the overall emission control lead to an decrease for the city average NO2 concentration.

A behavioral strategy to minimize air pollution exposure in pregnant women: a randomized controlled trial.

PubMed

Araban, Marzieh; Tavafian, Sedigheh Sadat; Zarandi, Saeed Motesaddi; Hidarnia, Ali Reza; Burri, Andrea; Montazeri, Ali

2017-04-04

Pregnant women and their fetus belong to a sensitive group in response to air pollution hazards. The aim of this study was to evaluate the effectiveness of a theory-based educational program to change pollution exposure behavior in pregnant women. In this randomized controlled trial, pregnant women attending a prenatal clinic in Tehran, Iran were selected and randomized into the experimental and control groups. The inclusion criteria were age between 18 and 35 years, having a history of pregnancies without adverse outcomes and not suffering from chronic diseases. Data collected at baseline and 2-month follow-up. At baseline face-to-face interviews were conducted using a valid and reliable questionnaire including items on demographic characteristics, stages of change, self-efficacy, decisional balance and practice regarding air pollution preventive behaviors. The intervention composed of three parts: motivational interviewing, a booklet and daily small message service (SMS). The control group received no intervention except receiving usual care. Follow-up data were collected after the intervention. Data were analyzed performing t-test, Mann-Whitney U test, and chi-squared. In all the data for 104 pregnant women (53 in the intervention and 51 in the control group) were analyzed. The mean age of participants was 27.2 (SD = 4.11) years and it was 22.89 (SD = 8.75) weeks for gestational age. At baseline there were no significant statistical differences between intervention and control groups on the study measures while we found significant group differences in terms of stages of change, self-efficacy, perceived benefits and practice regarding air pollution preventive behaviors at follow-up assessment (P < 0.05). The findings indicated that the TTM-based intervention was effective in increasing air pollution preventive behaviors among pregnant women. This study provided a framework to modify some psychosocial determinants of air pollution preventive behavior other than knowledge using constructs of Transtheoretical model of behavior change, additionally results suggests the importance of education and makes enlightenment of the air pollution risk knowledge accelerate. IRCT2012091010804N1.

Minimum airflow reset of single-duct VAV terminal boxes

NASA Astrophysics Data System (ADS)

Cho, Young-Hum

Single duct Variable Air Volume (VAV) systems are currently the most widely used type of HVAC system in the United States. When installing such a system, it is critical to determine the minimum airflow set point of the terminal box, as an optimally selected set point will improve the level of thermal comfort and indoor air quality (IAQ) while at the same time lower overall energy costs. In principle, this minimum rate should be calculated according to the minimum ventilation requirement based on ASHRAE standard 62.1 and maximum heating load of the zone. Several factors must be carefully considered when calculating this minimum rate. Terminal boxes with conventional control sequences may result in occupant discomfort and energy waste. If the minimum rate of airflow is set too high, the AHUs will consume excess fan power, and the terminal boxes may cause significant simultaneous room heating and cooling. At the same time, a rate that is too low will result in poor air circulation and indoor air quality in the air-conditioned space. Currently, many scholars are investigating how to change the algorithm of the advanced VAV terminal box controller without retrofitting. Some of these controllers have been found to effectively improve thermal comfort, indoor air quality, and energy efficiency. However, minimum airflow set points have not yet been identified, nor has controller performance been verified in confirmed studies. In this study, control algorithms were developed that automatically identify and reset terminal box minimum airflow set points, thereby improving indoor air quality and thermal comfort levels, and reducing the overall rate of energy consumption. A theoretical analysis of the optimal minimum airflow and discharge air temperature was performed to identify the potential energy benefits of resetting the terminal box minimum airflow set points. Applicable control algorithms for calculating the ideal values for the minimum airflow reset were developed and applied to actual systems for performance validation. The results of the theoretical analysis, numeric simulations, and experiments show that the optimal control algorithms can automatically identify the minimum rate of heating airflow under actual working conditions. Improved control helps to stabilize room air temperatures. The vertical difference in the room air temperature was lower than the comfort value. Measurements of room CO2 levels indicate that when the minimum airflow set point was reduced it did not adversely affect the indoor air quality. According to the measured energy results, optimal control algorithms give a lower rate of reheating energy consumption than conventional controls.

Air Cleaning Technologies

PubMed Central

2005-01-01

Executive Summary Objective This health technology policy assessment will answer the following questions: When should in-room air cleaners be used? How effective are in-room air cleaners? Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone? What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan? The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario’s capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry’s Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Clinical Need Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering, and personal protection methods. Engineering methods that are usually carried out by the building’s heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system’s effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes zoster, whereas close contact is required for the direct transmission of infectious diseases transmitted by droplets, such as influenza (the flu) and SARS. The Technology In-room air cleaners are supplied as portable or fixed devices. Fixed devices can be attached to either a wall or ceiling and are preferred over portable units because they have a greater degree of reliability (if installed properly) for achieving adequate room air mixing and airflow patterns, which are important for optimal effectiveness. Through a method of air recirculation, an in-room air cleaner can be used to increase room ventilation rates and if used to exhaust air out of the room it can create a negative-pressure room for airborne infection isolation (AII) when the building’s HVAC system cannot do so. A negative-pressure room is one where clean air flows into the room but contaminated air does not flow out of it. Contaminated room air is pulled into the in-room air cleaner and cleaned by passing through a series of filters, which remove the airborne infectious pathogens. The cleaned air is either recirculated into the room or exhausted outside the building. By filtering contaminated room air and then recirculating the cleaned air into the room, an in-room air cleaner can improve the room’s ventilation. By exhausting the filtered air to the outside the unit can create a negative-pressure room. There are many types of in-room air cleaners. They vary widely in the airflow rates through the unit, the type of air cleaning technology used, and the technical design. Crucial to maximizing the efficiency of any in-room air cleaner is its strategic placement and set-up within a room, which should be done in consultation with ventilation engineers, infection control experts, and/or industrial hygienists. A poorly positioned air cleaner may disrupt airflow patterns within the room and through the air cleaner, thereby compromising its air cleaning efficiency. The effectiveness of an in-room air cleaner to remove airborne pathogens from room air depends on several factors, including the airflow rate through the unit’s filter and the airflow patterns in the room. Tested under a variety of conditions, in-room air cleaners, including portable or ceiling mounted units with either a HEPA or a non-HEPA filter, portable units with UVGI lights only, or ceiling mounted units with combined HEPA filtration and UVGI lights, have been estimated to be between 30% and 90%, 99% and 12% and 80% effective, respectively. However, and although their effectiveness is variable, the United States Centers for Disease Control and Prevention has acknowledged in-room air cleaners as alternative technology for increasing room ventilation when this cannot be achieved by the building’s HVAC system with preference given to fixed recirculating systems over portable ones. Importantly, the use of an in-room air cleaner does not preclude either the need for health care workers and visitors to use personal protective equipment (N95 mask or equivalent) when entering AII rooms or health care facilities from meeting current regulatory requirements for airflow rates (ventilation rates) in buildings and airflow differentials for effective negative-pressure rooms. The Plasmacluster ion technology, developed in 2000, is an air purification technology. Its manufacturer, Sharp Electronics Corporation, says that it can disable airborne microorganisms through the generation of both positive and negative ions. (1) The functional unit is the hydroxyl, which is a molecule comprised of one oxygen molecule and one hydrogen atom. Plasmacluster ion air purifier uses a multilayer filter system composed of a prefilter, a carbon filter, an antibacterial filter, and a HEPA filter, combined with an ion generator to purify the air. The ion generator uses an alternating plasma discharge to split water molecules into positively and negatively charged ions. When these ions are emitted into the air, they are surrounded by water molecules and form cluster ions which are attracted to airborne particles. The cluster ion surrounds the airborne particle, and the positive and negative ions react to form hydroxyls. These hydroxyls steal the airborne particle’s hydrogen atom, which creates a hole in the particle’s outer protein membrane, thereby rendering it inactive. Because influenza is primarily acquired by large droplets and direct and indirect contact with an infectious person, any in-room air cleaner will have little benefit in controlling and preventing its spread. Therefore, there is no role for the Plasmacluster ion air purifier or any other in-room air cleaner in the control of the spread of influenza. Accordingly, for purposes of this review, the Medical Advisory Secretariat presents no further analysis of the Plasmacluster. Review Strategy The objective of the systematic review was to determine the effectiveness of in-room air cleaners with built in UVGI lights and HEPA filtration compared with those using HEPA filtration only. The Medical Advisory Secretariat searched the databases of MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, INAHATA (International Network of Agencies for Health Technology Assessment), Biosis Previews, Bacteriology Abstracts, Web of Science, Dissertation Abstracts, and NIOSHTIC 2. A meta-analysis was conducted if adequate data was available from 2 or more studies and where statistical and clinical heterogeneity among studies was not an issue. Otherwise, a qualitative review was completed. The GRADE system was used to summarize the quality of the body of evidence comprised of 1 or more studies. Summary of Findings There were no existing health technology assessments on air cleaning technology located during the literature review. The literature search yielded 59 citations of which none were retained. One study was retrieved from a reference list of a guidance document from the United States Centers for Disease Control and Prevention, which evaluated an in-room air cleaner with combined UVGI lights and HEPA filtration under 2 conditions: UVGI lights on and UVGI lights off. Experiments were performed using different ventilation rates and using an aerosolized pathogen comprised of Mycobaterium parafortuitum, a surrogate for the bacterium that causes tuberculosis. Effectiveness was measured as equivalent air changes per hour (eACH). This single study formed the body of evidence for our systematic review research question. Experimental Results The eACH rate for the HEPA-UVGI in-room air cleaner was statistically significantly greater when the UV lights were on compared with when the UV lights were off. (P < .05). However, subsequent experiments could not attribute this to the UVGI. Consequently, the results are inconclusive and an estimate of effect (benefit) is uncertain. The study was reviewed by a scientific expert and rated moderate for quality. Further analysis determined that there was some uncertainty in the directness of the outcome measure (eACH); thus, the GRADE level for the quality of the evidence was low indicating that an estimate of effect is very uncertain. There is uncertainty in the benefits of using in-room air cleaners with combined UVGI lights and HEPA filtration over systems that use HEPA filtration alone. However, there are no known risks to using systems with combined UVGI and HEPA technology compared with those with HEPA alone. There is an increase in the burden of cost including capital costs (cost of the device), operating costs (electricity usage), and maintenance costs (cleaning and replacement of UVGI lights) to using an in-room air cleaner with combined UVGI and HEPA technology compared with those with HEPA alone. Given the uncertainty of the estimate of benefits, an in-room air cleaner with HEPA technology only may be an equally reasonable alternative to using one with combined UVGI and HEPA technology Conclusions In-room air cleaners may be used to protect health care staff from air borne infectious pathogens such as tuberculosis, chicken pox, measles, and dessiminated herpes zoster. In addition, and although in-room air cleaners are not effective at protecting staff and preventing the spread of droplet-transmitted diseases such as influenza and SARS, they may be deployed in situations with a novel/emerging infectious agent whose epidemiology is not yet defined and where airborne transmission is suspected. It is preferable that in-room air cleaners be used with a fixed and permanent room placement when ventilation requirements must be improved and the HVAC system cannot be used. However, for acute (temporary) situations where a novel/emerging infectious agent presents whose epidemiology is not yet defined and where airborne transmission is suspected it may be prudent to use the in room air cleaner as a portable device until mode of transmission is confirmed. To maximize effectiveness, consultation with an environmental engineer and infection control expert should be undertaken before using an in-room air cleaner and protocols for maintenance and monitoring of these devices should be in place. If properly installed and maintained, in room air cleaners with HEPA or combined HEPA and UVGI air cleaning technology are effective in removing airborne pathogens. However, there is only weak evidence available at this time regarding the benefit of using an in-room air cleaner with combined HEPA and UVGI air cleaner technology instead of those with HEPA filter technology only. PMID:23074468

Using spacecraft trace contaminant control systems to cure sick building syndrome

NASA Technical Reports Server (NTRS)

Graf, John C.

1994-01-01

Many residential and commercial buildings with centralized, recirculating, heating ventilation and air conditioning systems suffer from 'Sick Building Syndrome.' Ventilation rates are reduced to save energy costs, synthetic building materials off-gas contaminants, and unsafe levels of volatile organic compounds (VOC's) accumulate. These unsafe levels of contaminants can cause irritation of eyes and throat, fatigue and dizziness to building occupants. Increased ventilation, the primary method of treating Sick Building Syndrome is expensive (due to increased energy costs) and recently, the effectiveness of increased ventilation has been questioned. On spacecraft venting is not allowed, so the primary methods of air quality control are; source control, active filtering, and destruction of VOC's. Four non-venting contaminant removal technologies; strict material selection to provide source control, ambient temperature catalytic oxidation, photocatalytic oxidation, and uptake by higher plants, may have potential application for indoor air quality control.

Effect of heating-ventilation-air conditioning system sanitation on airborne fungal populations in residential environments.

PubMed

Garrison, R A; Robertson, L D; Koehn, R D; Wynn, S R

1993-12-01

Commercial air duct sanitation services are advertised to the public as being effective in reducing indoor aeroallergen levels despite the absence of published supporting data. Eight residential heat-ventilation-air conditioning (HVAC) systems in six homes and seven HVAC systems in five homes in winter and summer, respectively, were sampled to determine fungal colony forming units (CFUs) prior to and after an HVAC sanitation procedure was performed by a local company. Two houses in which no sanitation procedure was performed served as controls in each study phase. Two sample sets were obtained at each HVAC system prior to cleaning in order to determine baseline CFU levels. The test HVAC systems were then cleaned, and the HVAC systems allowed to operate as desired by the residents. Posttreatment sampling was performed 48 hours and then weekly after cleaning for 8 weeks. The HVAC systems were analyzed by exposing sterile 2% malt extract media plates at a 90-degree angle to the air flow at the air supply and air return vents. The baseline CFUs were similar in the control and study houses. Eight weeks after sanitation, the study houses demonstrated an overall CFU reduction of 92% during winter and 84% during summer. No reduction in CFU values was observed over the 8-week study period for the houses selected as controls. Further, HVAC sanitation appeared to reduce the number of fungal colonies entering and leaving the HVAC system, suggesting that the HVAC contained a significant percentage of the total fungal load in these homes. These data suggest that HVAC sanitation may be an effective tool in reducing airborne fungal populations in residential environments.

Method and apparatus for in-cell vacuuming of radiologically contaminated materials

DOEpatents

Spadaro, Peter R.; Smith, Jay E.; Speer, Elmer L.; Cecconi, Arnold L.

1987-01-01

A vacuum air flow operated cyclone separator arrangement for collecting, handling and packaging loose contaminated material in accordance with acceptable radiological and criticality control requirements. The vacuum air flow system includes a specially designed fail-safe prefilter installed upstream of the vacuum air flow power supply. The fail-safe prefilter provides in-cell vacuum system flow visualization and automatically reduces or shuts off the vacuum air flow in the event of an upstream prefilter failure. The system is effective for collecting and handling highly contaminated radiological waste in the form of dust, dirt, fuel element fines, metal chips and similar loose material in accordance with radiological and criticality control requirements for disposal by means of shipment and burial.

Slip-Effect Functional Air Filter for Efficient Purification of PM2.5

PubMed Central

Zhao, Xinglei; Wang, Shan; Yin, Xia; Yu, Jianyong; Ding, Bin

2016-01-01

Fabrication of air filtration materials (AFM) that allow air to easily flow through while retaining particles is a significant and urgent need due to the harmful airborne particulate matter pollution; however, this is still a challenging research area. Herein, we report novel slip-effect functional nanofibrous membranes with decreased air resistance (reduction rate of 40%) due to the slip flow of air molecules on the periphery of nanofibers. This was achieved through careful control over the diameters of electrospun polyacrylonitrile fibers and aperture size of fiber assembly. Fiber assembly with 86% of fiber diameters between 60–100 nm was found to be most effective for slip flow, as these diameters are close to the mean free path of air molecules (65.3 nm). Significantly, an equilibrium factor τ = df/d2 has been introduced to elucidate the effect of distance of adjacent fibers on the drag force of airflow. Furthermore, the most effective aperture size (>3.5 μm) for slip-effect has been determined. Ultimately, the new material displayed low air resistance of 29.5 Pa, high purification efficiency of 99.09%, good transmittance of 77%, and long service life. The successful fabrication of such materials can facilitate the development of high-performance AFMs for various applications. PMID:27748419

Slip-Effect Functional Air Filter for Efficient Purification of PM2.5

NASA Astrophysics Data System (ADS)

Zhao, Xinglei; Wang, Shan; Yin, Xia; Yu, Jianyong; Ding, Bin

2016-10-01

Fabrication of air filtration materials (AFM) that allow air to easily flow through while retaining particles is a significant and urgent need due to the harmful airborne particulate matter pollution; however, this is still a challenging research area. Herein, we report novel slip-effect functional nanofibrous membranes with decreased air resistance (reduction rate of 40%) due to the slip flow of air molecules on the periphery of nanofibers. This was achieved through careful control over the diameters of electrospun polyacrylonitrile fibers and aperture size of fiber assembly. Fiber assembly with 86% of fiber diameters between 60-100 nm was found to be most effective for slip flow, as these diameters are close to the mean free path of air molecules (65.3 nm). Significantly, an equilibrium factor τ = df/d2 has been introduced to elucidate the effect of distance of adjacent fibers on the drag force of airflow. Furthermore, the most effective aperture size (>3.5 μm) for slip-effect has been determined. Ultimately, the new material displayed low air resistance of 29.5 Pa, high purification efficiency of 99.09%, good transmittance of 77%, and long service life. The successful fabrication of such materials can facilitate the development of high-performance AFMs for various applications.

Benefits Assessment of Algorithmically Combining Generic High Altitude Airspace Sectors

NASA Technical Reports Server (NTRS)

Bloem, Michael; Gupta, Pramod; Lai, Chok Fung; Kopardekar, Parimal

2009-01-01

In today's air traffic control operations, sectors that have traffic demand below capacity are combined so that fewer controller teams are required to manage air traffic. Controllers in current operations are certified to control a group of six to eight sectors, known as an area of specialization. Sector combinations are restricted to occur within areas of specialization. Since there are few sector combination possibilities in each area of specialization, human supervisors can effectively make sector combination decisions. In the future, automation and procedures will allow any appropriately trained controller to control any of a large set of generic sectors. The primary benefit of this will be increased controller staffing flexibility. Generic sectors will also allow more options for combining sectors, making sector combination decisions difficult for human supervisors. A sector-combining algorithm can assist supervisors as they make generic sector combination decisions. A heuristic algorithm for combining under-utilized air space sectors to conserve air traffic control resources has been described and analyzed. Analysis of the algorithm and comparisons with operational sector combinations indicate that this algorithm could more efficiently utilize air traffic control resources than current sector combinations. This paper investigates the benefits of using the sector-combining algorithm proposed in previous research to combine high altitude generic airspace sectors. Simulations are conducted in which all the high altitude sectors in a center are allowed to combine, as will be possible in generic high altitude airspace. Furthermore, the algorithm is adjusted to use a version of the simplified dynamic density (SDD) workload metric that has been modified to account for workload reductions due to automatic handoffs and Automatic Dependent Surveillance Broadcast (ADS-B). This modified metric is referred to here as future simplified dynamic density (FSDD). Finally, traffic demand sets with increased air traffic demand are used in the simulations to capture the expected growth in air traffic demand by the mid-term.

Thermal modelling and control of 130kw direct contact (salt/air) heat exchanger

NASA Astrophysics Data System (ADS)

Qureshi, Omer A.; Calvet, Nicolas; Armstrong, Peter R.

2017-06-01

This work investigates the transient response of a certain type of direct contact heat exchanger (DCHX) that consists of packing (Raschig Rings) to increase the surface area for effective heat transfer between molten salt and air. Molten salt from the hot tank enters the heat exchanger (HX) and exit after heating the air still in the molten form. Thermal capacitance of the HX, mainly due to packing and resident salt inside the HX, results in strong transient response. Pure delay from salt residence time may also impact transient response. Both phenomena have been modelled in this paper. A Proportional-Integral controller (PI control) performance has been evaluated to maintain the minimum salt temperature above avoid crystallization temperature of the salt.

Investigation of air transportation technology at Princeton University, 1984

NASA Technical Reports Server (NTRS)

Stengel, Robert F.

1987-01-01

The Air Transportation Technology Program at Princeton University, a program emphasizing graduate and undergraduate student research, proceeded along four avenues during 1984: (1) guidance and control strategies for penetration of microbursts and wind shear; (2) application of artificial intelligence in flight control systems; (3) effects of control saturation on closed loop stability; and (4) response of open loop unstable aircraft. Areas of investigation relate to guidance and control of commercial transports as well as to general aviation aircraft. Interaction between the flight crew and automatic systems is a subject of principle concern. These areas of investigation are briefly discussed.

Thirty years of research and development of air cushion vehicles

NASA Astrophysics Data System (ADS)

Bertelsen, William R.

This paper describes the conception of the air cushion vehicle (ACV) from experiments with the ground effect of a VTOL aircraft model. Then it describes the evolution of the ultimate ACV drive system through building and testing many models and 16 full-scale ACV to arrive at complete controllability. Adequate control of the frictionless craft, which are without inherent yaw stability, requires control force of the order of magnitude of propulsion. The derived gimbal fans provide such control force in the form of direct thrust, which is instantly available in any of 360 degrees, meterable, instantly cancelable, and reversible.

Short-term effects of air pollution on daily hospital admissions for cardiovascular diseases in western China.

PubMed

Ma, Yuxia; Zhang, Haipeng; Zhao, Yuxin; Zhou, Jianding; Yang, Sixu; Zheng, Xiaodong; Wang, Shigong

2017-06-01

Controlling the confounding factors on cardiovascular diseases, such as long-time trend, calendar effect, and meteorological factors, a generalized additive model (GAM) was used to investigate the short-term effects of air pollutants (PM 10 , SO 2 , and NO 2 ) on daily cardiovascular admissions from March 1st to May 31st during 2007 to 2011 in Lanzhou, a heavily polluted city in western China. The influences of air pollutants were examined with different lag structures, and the potential effect modification by dust storm in spring was also investigated. Significant associations were found between air pollutants and hospital admissions for cardiovascular diseases both on dust event days and non-dust event days in spring. Air pollutants had lag effects on different age and gender groups. Relative risks (RRs) and their 95% confidence intervals (CIs) associated with a 10 μg/m 3 increase were 1.14 (1.04~1.26) on lag1 for PM 10 , 1.31 (1.21~1.51) on lag01 for SO 2 , and 1.96 (1.49~2.57) on lag02 for NO 2 on dust days. Stronger effects of air pollutants were observed for females and the elderly (≥60 years). Our analysis concluded that the effects of air pollutants on cardiovascular admissions on dust days were significantly stronger than non-dust days. The current study strengthens the evidence of effects of air pollution on health and dust-exacerbated cardiovascular admissions in Lanzhou.

From where they look to what they think: Determining controller cognitive strategies from oculometer scanning data

NASA Technical Reports Server (NTRS)

Cushing, Steven

1989-01-01

The behavior and cognition of air traffic controllers from oculometer scanning data already obtained for another purpose was studied. There was very little work done to develop models of air traffic controllers, much of what was done was done at Langley. One aim of developing such models is to use them as the basis of decision-support or expert-system tools to assist controllers in their tasks. Such tools are more likely to be effective if they incorporate the strategies that controllers actually use, rather than steering them in what might be felt to be unnatural directions.

40 CFR 81.77 - Puerto Rico 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 Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control Region...

40 CFR 81.77 - Puerto Rico 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 Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control Region...

40 CFR 81.77 - Puerto Rico 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 Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control Region...

40 CFR 81.77 - Puerto Rico 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 Puerto Rico Air Quality Control Region... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.77 Puerto Rico Air Quality Control Region. The Puerto Rico Air Quality Control Region...

Energy Savings Analysis for Energy Monitoring and Control Systems

DTIC Science & Technology

1995-01-01

for evaluating design and construction a:-0 quality, and for studying the effectiveness of air - tightening AC retrofits. No simple relationship...Energy These models of residential infiltration are based on statistical "Resource Center (1983) include information on air tightening in fits of

AMBIENT AIR QUALITY AND SELECTED BIRTH DEFECTS, SEVEN COUNTY STUDY, TEXAS, 1997-2000

EPA Science Inventory

Background: A number of epidemiologic investigations have shown adverse effects of ambient air pollution on reproductive outcomes. A recent case-control study found associations between

second gestational month carbon monoxide and ozone exposure and elevated risks of selec...

AIRBORNE PARTICLE SIZES AND SOURCES FOUND IN INDOOR AIR

EPA Science Inventory

As concern about indoor air quality (IAQ) has grown in recent years, understanding indoor aerosols has become increasingly important so that control techniques may be implemented to reduce damaging health effects and soiling problems. This paper begins with a brief look at the me...

Long-term mortality benefits of air quality improvement during the twelfth five-year-plan period in 31 provincial capital cities of China

NASA Astrophysics Data System (ADS)

Liu, Tao; Cai, Yuanyuan; Feng, Baixiang; Cao, Ganxiang; Lin, Hualiang; Xiao, Jianpeng; Li, Xing; Liu, Sha; Pei, Lei; Fu, Li; Yang, Xinyi; Zhang, Bo; Ma, Wenjun

2018-01-01

The severe air pollution across China in the past several years has made the Chinese government recognize its significant impacts on public health and society, and take enormous efforts to improve the air quality all over the country, especially during the Twelfth Five-Year Plan (12th FYP). However, the overall effectiveness of these air pollution control policies remains unclear. In this study, we selected the 31 municipalities and provincial capital cities in mainland China as study settings. We collected the annual average population size, mortality rates (total mortality and mortality due to cardiovascular diseases, respiratory diseases, total cancer, lung cancer and breast cancer) and concentrations of air pollutants (PM10, PM2.5, SO2 and NO2) in each capital city from 2010 to 2015 from national or local Statistical Yearbooks. The effect sizes of air pollutants on mortality were obtained from previously published meta analyses or cohort studies. We first estimated the annual mortality rates attributed to the changes in air pollutant concentrations for every city in each year. Then, we further estimated the mortality benefits in the scenarios where the air quality had reached the grade II levels of Chinese Ambient Air Quality Standards (CAAQS) and World Health Organization (WHO) guidelines. In most capital cities, we observed dominant decreases in air pollutant concentrations during the 12th FYP, particularly from 2013 to 2015, which has led to significant mortality benefits for the public. A total of 121,658 deaths (0.441‰) have been prevented due to the decrease of PM2.5concentrations from 2013 to 2015 in all included cities. The morality benefits were larger in capital cities located in the key regions (the three main regions and ten city groups) than the other cities. In addition, more mortality benefits could be obtained in the future if the air quality reaches the grade II levels of Chinese Ambient Air Quality Standards (CAAQS) or WHO guidelines. We concluded that substantial mortality benefits achieved during the 12th FYP may be attributed to the improvements in China's air quality, which indicated the significant effectiveness of air pollution control policies.

[The preliminary study on nursing the extraction of mandibular mesioangular impacted third molar using reversal high-speed air turbine].

PubMed

Song, Juan; Bi, Xiaoqin

2012-08-01

To study the nursing methods and its effect in mandibular mesioangular impacted third molar extraction with reversal high-speed air turbine. 60 patients with mandibular mesioangular impacted third molar were selected in this study, who were treated in Department of Senior Dentists, West China School of Stomatology, Sichuan University, between June to December 2010. They were randomly and equally divided into control group and experimental group (n=30). The former was treated with tradition chisel splint method while the latter was treated with reversal high-speed air turbine extraction and provided appropriate nursing interventions. Postoperative reactions and wound healing status were evaluated through consultation. There were significant differences between control group and experimental group in terms of postoperative bleeding wound, swelling, dry socket and so on (P<0.05). Mandibular mesioangular impacted third molar extraction with reversal high-speed air turbine is effective, and the corresponding nursing measure is worthy further promotion.

A Bayesian analysis of the impact of air pollution episodes on cardio-respiratory hospital admissions in the Greater London area.

PubMed

Blangiardo, Marta; Richardson, Sylvia; Gulliver, John; Hansell, Anna

2011-02-01

In this paper, we present a Bayesian hierarchical model to evaluate the effect of long-range and local range PM(10) during air pollution episodes on hospital admissions for cardio-respiratory diseases in Greater London. These episodes in 2003 are matched with the same periods during the previous year, used as a control. A baseline dose-response function is estimated for the controls and carried forward in the episodes, which are characterised by an additional component that estimates their specific effect on the health outcome.

Evaluation of the Effectiveness of Wet Blast Cleaning Methods of Surface Preparation

DTIC Science & Technology

1985-06-01

for Air Abrasive Wet Blast: Complete System Water Abrasive Mixing Chamber in Slurry Blast Unit Schematic of unit Control Unit Slurry Blast — Air/Water...this discussion we present some general. user guidelines regarding what to look for in con- sidering the use or purchase of wet blasting equipment...These units use compressed air as the medium to propel the eroding material. They differ from air abrasive wet blast units in that the abrasive is mixed

Likelihood of achieving air quality targets under model uncertainties.

PubMed

Digar, Antara; Cohan, Daniel S; Cox, Dennis D; Kim, Byeong-Uk; Boylan, James W

2011-01-01

Regulatory attainment demonstrations in the United States typically apply a bright-line test to predict whether a control strategy is sufficient to attain an air quality standard. Photochemical models are the best tools available to project future pollutant levels and are a critical part of regulatory attainment demonstrations. However, because photochemical models are uncertain and future meteorology is unknowable, future pollutant levels cannot be predicted perfectly and attainment cannot be guaranteed. This paper introduces a computationally efficient methodology for estimating the likelihood that an emission control strategy will achieve an air quality objective in light of uncertainties in photochemical model input parameters (e.g., uncertain emission and reaction rates, deposition velocities, and boundary conditions). The method incorporates Monte Carlo simulations of a reduced form model representing pollutant-precursor response under parametric uncertainty to probabilistically predict the improvement in air quality due to emission control. The method is applied to recent 8-h ozone attainment modeling for Atlanta, Georgia, to assess the likelihood that additional controls would achieve fixed (well-defined) or flexible (due to meteorological variability and uncertain emission trends) targets of air pollution reduction. The results show that in certain instances ranking of the predicted effectiveness of control strategies may differ between probabilistic and deterministic analyses.

75 FR 18061 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Control of Air Pollution...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... Promulgation of Air Quality Implementation Plans; Texas; Control of Air Pollution From Motor Vehicles AGENCY... Chapter 114, Control of Air Pollution from Motor Vehicles. These revisions consist of the new Rebate Grant... air pollution regulations and control strategies to ensure that air quality meets the National Ambient...

Effects of personal air pollution exposure on asthma symptoms, lung function and airway inflammation.

PubMed

Chambers, L; Finch, J; Edwards, K; Jeanjean, A; Leigh, R; Gonem, S

2018-03-11

There is evidence that air pollution increases the risk of asthma hospitalizations and healthcare utilization, but the effects on day-to-day asthma control are not fully understood. We undertook a prospective single-centre panel study to test the hypothesis that personal air pollution exposure is associated with asthma symptoms, lung function and airway inflammation. Thirty-two patients with a clinical diagnosis of asthma were provided with a personal air pollution monitor (Cairclip NO 2 /O 3 ) which was kept on or around their person throughout the 12-week follow-up period. Ambient levels of NO 2 and particulate matter were modelled based upon satellite imaging data. Directly measured ozone, NO 2 and particulate matter levels were obtained from a monitoring station in central Leicester. Participants made daily electronic records of asthma symptoms, peak expiratory flow and exhaled nitric oxide. Spirometry and asthma symptom questionnaires were completed at fortnightly study visits. Data were analysed using linear mixed effects models and cross-correlation. Cairclip exposure data were of good quality with clear evidence of diurnal variability and a missing data rate of approximately 20%. We were unable to detect consistent relationships between personal air pollution exposure and clinical outcomes in the group as a whole. In an exploratory subgroup analysis, total oxidant exposure was associated with increased daytime symptoms in women but not men. We did not find compelling evidence that air pollution exposure impacts on day-to-day clinical control in an unselected asthma population, but further studies are required in larger populations with higher exposure levels. Women may be more susceptible than men to the effects of air pollution, an observation which requires confirmation in future studies. © 2018 John Wiley & Sons Ltd.

Robustness analysis of an air heating plant and control law by using polynomial chaos

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

Colón, Diego; Ferreira, Murillo A. S.; Bueno, Átila M.

2014-12-10

This paper presents a robustness analysis of an air heating plant with a multivariable closed-loop control law by using the polynomial chaos methodology (MPC). The plant consists of a PVC tube with a fan in the air input (that forces the air through the tube) and a mass flux sensor in the output. A heating resistance warms the air as it flows inside the tube, and a thermo-couple sensor measures the air temperature. The plant has thus two inputs (the fan's rotation intensity and heat generated by the resistance, both measured in percent of the maximum value) and two outputsmore » (air temperature and air mass flux, also in percent of the maximal value). The mathematical model is obtained by System Identification techniques. The mass flux sensor, which is nonlinear, is linearized and the delays in the transfer functions are properly approximated by non-minimum phase transfer functions. The resulting model is transformed to a state-space model, which is used for control design purposes. The multivariable robust control design techniques used is the LQG/LTR, and the controllers are validated in simulation software and in the real plant. Finally, the MPC is applied by considering some of the system's parameters as random variables (one at a time, and the system's stochastic differential equations are solved by expanding the solution (a stochastic process) in an orthogonal basis of polynomial functions of the basic random variables. This method transforms the stochastic equations in a set of deterministic differential equations, which can be solved by traditional numerical methods (That is the MPC). Statistical data for the system (like expected values and variances) are then calculated. The effects of randomness in the parameters are evaluated in the open-loop and closed-loop pole's positions.« less

40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Quality Control Regions § 81.88 Billings Intrastate Air Quality Control Region. The Metropolitan Billings Intrastate Air Quality Control Region (Montana) has been renamed the Billings Intrastate Air Quality Control... to by Montana authorities as follows: Sec. 481.168Great Falls Intrastate Air Quality Control Region...

40 CFR 81.88 - Billings Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Quality Control Regions § 81.88 Billings Intrastate Air Quality Control Region. The Metropolitan Billings Intrastate Air Quality Control Region (Montana) has been renamed the Billings Intrastate Air Quality Control... to by Montana authorities as follows: Sec. 481.168Great Falls Intrastate Air Quality Control Region...

Herbal Extract Incorporated Nanofiber Fabricated by an Electrospinning Technique and its Application to Antimicrobial Air Filtration.

PubMed

Choi, Jeongan; Yang, Byeong Joon; Bae, Gwi-Nam; Jung, Jae Hee

2015-11-18

Recently, with the increased attention to indoor air quality, antimicrobial air filtration techniques have been studied widely to inactivate hazardous airborne microorganisms effectively. In this study, we demonstrate herbal extract incorporated (HEI) nanofibers synthesized by an electrospinning technique and their application to antimicrobial air filtration. As an antimicrobial herbal material, an ethanolic extract of Sophora flavescens, which exhibits great antibacterial activity against pathogens, was mixed with the polymer solution for the electrospinning process. We measured various characteristics of the synthesized HEI nanofibers, such as fiber morphology, fiber size distribution, and thermal stability. For application of the electrospun HEI nanofibers, we made highly effective air filters with 99.99% filtration efficiency and 99.98% antimicrobial activity against Staphylococcus epidermidis. The pressure drop across the HEI nanofiber air filter was 4.75 mmH2O at a face air velocity of 1.79 cm/s. These results will facilitate the implementation of electrospun HEI nanofiber techniques to control air quality and protect against hazardous airborne microorganisms.

40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial area...

40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the Northeast...

40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial area...

40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of the...

40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial area...

40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the Southeastern...

40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of the...

40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the Northeast...

40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial area...

40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.78 Metropolitan Portland Intrastate Air Quality Control Region. The Metropolitan Portland Intrastate Air Quality Control Region (Maine) consists of the territorial area...

40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.78 Metropolitan Portland Intrastate Air Quality Control Region. The Metropolitan Portland Intrastate Air Quality Control Region (Maine) consists of the territorial area...

40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial area...

40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the Northeast...

40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial area...

40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the Southeastern...

40 CFR 81.29 - Metropolitan Indianapolis Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Air Quality Control Region. 81.29 Section 81.29 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.29 Metropolitan Indianapolis Intrastate Air Quality Control...

40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of the...

40 CFR 81.29 - Metropolitan Indianapolis Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Air Quality Control Region. 81.29 Section 81.29 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.29 Metropolitan Indianapolis Intrastate Air Quality Control...

40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of the...

40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the Southeastern...

40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the Southeastern...

40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial area...

40 CFR 81.29 - Metropolitan Indianapolis Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Air Quality Control Region. 81.29 Section 81.29 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.29 Metropolitan Indianapolis Intrastate Air Quality Control...

40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial area...

40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial area...

40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of the...

40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial area...

40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial area...

40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial area...

40 CFR 81.29 - Metropolitan Indianapolis Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Air Quality Control Region. 81.29 Section 81.29 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.29 Metropolitan Indianapolis Intrastate Air Quality Control...

40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of the...

40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of the...

40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of the...

40 CFR 81.44 - Metropolitan Memphis Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.44 Metropolitan Memphis Interstate Air Quality Control Region. The Metropolitan Memphis Interstate Air Quality Control Region (Arkansas-Mississippi-Tennessee) consists of the...

40 CFR 81.16 - Metropolitan Denver Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.16 Metropolitan Denver Intrastate Air Quality Control Region. The Metropolitan Denver Intrastate Air Quality Control Region (Colorado) consists of the territorial area...

40 CFR 81.28 - Metropolitan Baltimore Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.28 Metropolitan Baltimore Intrastate Air Quality Control Region. The Metropolitan Baltimore Intrastate Air Quality Control Region (Maryland) consists of the territorial area...

40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the Southeastern...

40 CFR 81.19 - Metropolitan Boston Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.19 Metropolitan Boston Intrastate Air Quality Control Region. The Metropolitan Boston Intrastate Air Quality Control Region (Massachusetts) consists of the territorial area...

40 CFR 81.29 - Metropolitan Indianapolis Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Air Quality Control Region. 81.29 Section 81.29 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.29 Metropolitan Indianapolis Intrastate Air Quality Control...

40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.78 Metropolitan Portland Intrastate Air Quality Control Region. The Metropolitan Portland Intrastate Air Quality Control Region (Maine) consists of the territorial area...

40 CFR 81.62 - Northeast Mississippi Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.62 Northeast Mississippi Intrastate Air Quality Control Region. The Alabama-Mississippi-Tennessee Interstate Air Quality Control Region has been renamed the Northeast...

40 CFR 81.31 - Metropolitan Providence Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.31 Metropolitan Providence Interstate Air Quality Control Region. The Metropolitan Providence Interstate Air Quality Control Region (Rhode Island-Massachusetts) consists of the...

Effects of modeling errors on trajectory predictions in air traffic control automation

NASA Technical Reports Server (NTRS)

Jackson, Michael R. C.; Zhao, Yiyuan; Slattery, Rhonda

1996-01-01

Air traffic control automation synthesizes aircraft trajectories for the generation of advisories. Trajectory computation employs models of aircraft performances and weather conditions. In contrast, actual trajectories are flown in real aircraft under actual conditions. Since synthetic trajectories are used in landing scheduling and conflict probing, it is very important to understand the differences between computed trajectories and actual trajectories. This paper examines the effects of aircraft modeling errors on the accuracy of trajectory predictions in air traffic control automation. Three-dimensional point-mass aircraft equations of motion are assumed to be able to generate actual aircraft flight paths. Modeling errors are described as uncertain parameters or uncertain input functions. Pilot or autopilot feedback actions are expressed as equality constraints to satisfy control objectives. A typical trajectory is defined by a series of flight segments with different control objectives for each flight segment and conditions that define segment transitions. A constrained linearization approach is used to analyze trajectory differences caused by various modeling errors by developing a linear time varying system that describes the trajectory errors, with expressions to transfer the trajectory errors across moving segment transitions. A numerical example is presented for a complete commercial aircraft descent trajectory consisting of several flight segments.

Flight Control of Biomimetic Air Vehicles Using Vibrational Control and Averaging

NASA Astrophysics Data System (ADS)

Tahmasian, Sevak; Woolsey, Craig A.

2017-08-01

A combination of vibrational inputs and state feedback is applied to control the flight of a biomimetic air vehicle. First, a control strategy is developed for longitudinal flight, using a quasi-steady aerodynamic model and neglecting wing inertial effects. Vertical and forward motion is controlled by modulating the wings' stroke and feather angles, respectively. Stabilizing control parameter values are determined using the time-averaged dynamic model. Simulations of a system resembling a hawkmoth show that the proposed controller can overcome modeling error associated with the wing inertia and small parameter uncertainties when following a prescribed trajectory. After introducing the approach through an application to longitudinal flight, the control strategy is extended to address flight in three-dimensional space.

Pollution reduction technologies being applied to small coal-fired boiler systems in Poland

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

Markussen, J.M.; Gyorke, D.F.

1997-12-31

To help in alleviating air pollution problems in Poland, various US environmental technologies are being installed in the city of Krakow to reduce emissions from short-stack coal- and coke-fired boilers. Introduction of low-cost, effective US pollution abatement and energy efficiency technologies is being completed through the US-Polish Krakow Clean Fossil Fuels and Energy Efficiency Program. Seven US firms are currently participating in the program; five projects are well under way and two are in the design phase. The technologies being applied in Krakow include modern district heating equipment and controls, coal preparation techniques, micronized coal combustion, automatic combustion controls, andmore » high-efficiency particulate control equipment. These technologies will be discussed along with pollutant reduction results obtained to date. Applications of these technologies are providing some efficient and economical answers to Krakow`s severe air pollution problems. Certainly, these technologies could be equally effective in many industrial cities throughout the world with similar air pollution concerns.« less

Air Support Control Officer Individual Position Training Simulation

DTIC Science & Technology

2017-06-01

Analysis design development implementation evaluation ASCO Air support control officer ASLT Air support liaison team ASNO Air support net operator...Instructional system design LSTM Long-short term memory MACCS Marine Air Command and Control System MAGTF Marine Air Ground Task Force MASS Marine Air...information to designated MACCS agencies. ASCOs play an important part in facilitating the safe and successful conduct of air operations in DASC- controlled

Driver air bag effectiveness by severity of the crash.

PubMed Central

Segui-Gomez, M

2000-01-01

OBJECTIVES: This analysis provided effectiveness estimates of the driver-side air bag while controlling for severity of the crash and other potential confounders. METHODS: Data were from the National Automotive Sampling System (1993-1996). Injury severity was described on the basis of the Abbreviated Injury Scale, Injury Severity Score, Functional Capacity Index, and survival. Ordinal, linear, and logistic multivariate regression methods were used. RESULTS: Air bag deployment in frontal or near-frontal crashes decreases the probability of having severe and fatal injuries (e.g., Abbreviated Injury Scale score of 4-6), including those causing a long-lasting high degree of functional limitation. However, air bag deployment in low-severity crashes increases the probability that a driver (particularly a woman) will sustain injuries of Abbreviated Injury Scale level 1 to 3. Air bag deployment exerts a net injurious effect in low-severity crashes and a net protective effect in high-severity crashes. The level of crash severity at which air bags are protective is higher for female than for male drivers. CONCLUSIONS: Air bag improvement should minimize the injuries induced by their deployment. One possibility is to raise their deployment level so that they deploy only in more severe crashes. PMID:11029991

Workload-Matched Adaptive Automation Support of Air Traffic Controller Information Processing Stages

NASA Technical Reports Server (NTRS)

Kaber, David B.; Prinzel, Lawrence J., III; Wright, Melanie C.; Clamann, Michael P.

2002-01-01

Adaptive automation (AA) has been explored as a solution to the problems associated with human-automation interaction in supervisory control environments. However, research has focused on the performance effects of dynamic control allocations of early stage sensory and information acquisition functions. The present research compares the effects of AA to the entire range of information processing stages of human operators, such as air traffic controllers. The results provide evidence that the effectiveness of AA is dependent on the stage of task performance (human-machine system information processing) that is flexibly automated. The results suggest that humans are better able to adapt to AA when applied to lower-level sensory and psychomotor functions, such as information acquisition and action implementation, as compared to AA applied to cognitive (analysis and decision-making) tasks. The results also provide support for the use of AA, as compared to completely manual control. These results are discussed in terms of implications for AA design for aviation.

Aerodynamic Leidenfrost effect

NASA Astrophysics Data System (ADS)

Gauthier, Anaïs; Bird, James C.; Clanet, Christophe; Quéré, David

2016-12-01

When deposited on a plate moving quickly enough, any liquid can levitate as it does when it is volatile on a very hot solid (Leidenfrost effect). In the aerodynamic Leidenfrost situation, air gets inserted between the liquid and the moving solid, a situation that we analyze. We observe two types of entrainment. (i) The thickness of the air gap is found to increase with the plate speed, which is interpreted in the Landau-Levich-Derjaguin frame: Air is dynamically dragged along the surface and its thickness results from a balance between capillary and viscous effects. (ii) Air set in motion by the plate exerts a force on the levitating liquid. We discuss the magnitude of this aerodynamic force and show that it can be exploited to control the liquid and even to drive it against gravity.

Probe into Gaseous Pollution and Assessment of Air Quality Benefit under Sector Dependent Emission Control Strategies over Megacities in Yangtze River Delta, China

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

Dong, Xinyi; Gao, Yang; Fu, Joshua S.

On February 29th 2012, China published its new National Ambient Air Quality Standard (CH-NAAQS) aiming at revising the standards and measurements for both gaseous pollutants including ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2), and also particle pollutants including PM10 and PM2.5. In order to understand the air pollution status regarding this new standard, the integrated MM5/CMAQ modeling system was applied over Yangtze River Delta (YRD) within this study to examine the criteria gaseous pollutants listed in the new CH-NAAQS. Sensitivity simulations were also conducted to assess the responses of gaseous pollutants under 8 different sector-dependent emission reduction scenariosmore » in order to evaluate the potential control strategies. 2006 was selected as the simulation year in order to review the air quality condition at the beginning of China’s 11th Five-Year-Plan (FYP, from 2006 to 2010), and also compared with air quality status in 2010 as the end of 11th FYP to probe into the effectiveness of the national emission control efforts. Base case simulation showed distinct seasonal variation for gaseous pollutants: SO2, and NO2 were found to have higher surface concentrations in winter while O3 was found to have higher concentrations in spring and summer than other seasons. According to the analyses focused on 3 megacities within YRD, Shanghai, Nanjing, and Hangzhou, we found different air quality conditions among the cities: NO2 was the primary pollutant that having the largest number of days exceeding the CH-NAAQS daily standard (80 μg/m3) in Shanghai (59 days) and Nanjing (27 days); SO2 was the primary pollutant with maximum number of days exceeding daily air quality standard (150 μg/m3) in Hangzhou (28 days), while O3 exceeding the daily maximum 8-hour standard (160 μg/m3) for relatively fewer days in all the three cities (9 days in Shanghai, 14 days in Nanjing, and 11 days in Hangzhou). Simulation results from predefined potential applicable emission control scenarios suggested significant air quality improvements from emission reduction: 90% of SO2 emission removed from power plant in YRD would be able to reduce more than 85% of SO2 pollution, 85% NOx emission reduction from power plant would reduce more than 60% of NO2 pollution, in terms of reducing the number of days exceeding daily air quality standard. NOx emission reduction from transportation and industry were also found to effectively reduce NO2 pollution but less efficient than emission control from power plants. We also found that multi-pollutants emission control including both NOx and VOC would be a better strategy than independent NOx control over YRD which is China’s 12th Five-Year-Plan (from 2011 to 2015), because O3 pollution would be increased as a side effect of NOx control and counteract NO2 pollution reduction benefit.« less

40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been revised...

40 CFR 81.45 - Metropolitan Atlanta Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.45 Metropolitan Atlanta Intrastate Air Quality Control Region. The Metropolitan Atlanta Intrastate Air Quality Control Region (Georgia) has been revised to consist of the...

40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by the...

40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial area...

40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial area...

40 CFR 81.45 - Metropolitan Atlanta Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.45 Metropolitan Atlanta Intrastate Air Quality Control Region. The Metropolitan Atlanta Intrastate Air Quality Control Region (Georgia) has been revised to consist of the...

40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma Intrastate...

40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of the...

40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by the...

40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of the...

40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist of...

40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the territorial...

40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by the...

40 CFR 81.79 - Northeastern Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.79 Northeastern Oklahoma Intrastate Air Quality Control Region. The Metropolitan Tulsa Intrastate Air Quality Control Region has been renamed the Northeastern Oklahoma Intrastate...

40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to consist...

40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial area...

40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial area...

40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of the...

40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of the...

40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by the...

40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial area...

40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial area...

40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma Intrastate...

40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the territorial...

40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial area...

40 CFR 81.45 - Metropolitan Atlanta Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.45 Metropolitan Atlanta Intrastate Air Quality Control Region. The Metropolitan Atlanta Intrastate Air Quality Control Region (Georgia) has been revised to consist of the...

40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma Intrastate...

40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the territorial...

40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to consist...

40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist of...

40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial area...

40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial area...

40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist of...

40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial area...

40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been revised...

40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of the...

40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of the...

40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial area...

40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial area...

40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the territorial...

40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of the...

40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist of...

40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to consist...

40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of the...

40 CFR 81.45 - Metropolitan Atlanta Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.45 Metropolitan Atlanta Intrastate Air Quality Control Region. The Metropolitan Atlanta Intrastate Air Quality Control Region (Georgia) has been revised to consist of the...

40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to consist...

40 CFR 81.87 - Metropolitan Boise Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.87 Metropolitan Boise Intrastate Air Quality Control Region. The Metropolitan Boise Intrastate Air Quality Control Region (Idaho) consists of the territorial area encompassed...

40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma Intrastate...

40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been revised...

40 CFR 81.79 - Northeastern Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.79 Northeastern Oklahoma Intrastate Air Quality Control Region. The Metropolitan Tulsa Intrastate Air Quality Control Region has been renamed the Northeastern Oklahoma Intrastate...

40 CFR 81.43 - Metropolitan Toledo Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.43 Metropolitan Toledo Interstate Air Quality Control Region. The Metropolitan Toledo Interstate Air Quality Control Region (Ohio-Michigan) consists of the territorial area...

40 CFR 81.49 - Southeast Florida Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.49 Southeast Florida Intrastate Air Quality Control Region. The Southeast Florida Intrastate Air Quality Control Region is redesignated to consist of the territorial area...

40 CFR 81.20 - Metropolitan Cincinnati Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.20 Metropolitan Cincinnati Interstate Air Quality Control Region. The Metropolitan Cincinnati Interstate Air Quality Control Region (Ohio-Kentucky-Indiana) is revised to consist of...

40 CFR 81.75 - Metropolitan Charlotte Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.75 Metropolitan Charlotte Interstate Air Quality Control Region. The Metropolitan Charlotte Interstate Air Quality Control Region (North Carolina-South Carolina) has been revised...

40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma Intrastate...

40 CFR 81.24 - Niagara Frontier Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.24 Niagara Frontier Intrastate Air Quality Control Region. The Niagara Frontier Intrastate Air Quality Control Region (New York) consists of the territorial area...

40 CFR 81.23 - Southwest Pennsylvania Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.23 Southwest Pennsylvania Intrastate Air Quality Control Region. The Southwest Pennsylvania Intrastate Air Quality Control Region is redesignated to consist of the territorial...

40 CFR 81.59 - Cumberland-Keyser Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.59 Cumberland-Keyser Interstate Air Quality Control Region. The Cumberland-Keyser Interstate Air Quality Control Region (Maryland-West Virginia) has been revised to consist...

40 CFR 81.14 - Metropolitan Chicago Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.14 Metropolitan Chicago Interstate Air Quality Control Region. The Metropolitan Chicago Interstate Air Quality Control Region (Illinois-Indiana) is revised to consist of the...

40 CFR 81.45 - Metropolitan Atlanta Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.45 Metropolitan Atlanta Intrastate Air Quality Control Region. The Metropolitan Atlanta Intrastate Air Quality Control Region (Georgia) has been revised to consist of the...

40 CFR 81.41 - Metropolitan Birmingham Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.41 Metropolitan Birmingham Intrastate Air Quality Control Region. The Metropolitan Birmingham Intrastate Air Quality Control Region (Alabama) has been revised to consist of the...

40 CFR 81.34 - Metropolitan Dayton Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.34 Metropolitan Dayton Intrastate Air Quality Control Region. The Metropolitan Dayton Intrastate Air Quality Control Region consists of the territorial area encompassed by the...

Air Pollution Control Policies in China: A Retrospective and Prospects.

PubMed

Jin, Yana; Andersson, Henrik; Zhang, Shiqiu

2016-12-09

With China's significant role on pollution emissions and related health damage, deep and up-to-date understanding of China's air pollution policies is of worldwide relevance. Based on scientific evidence for the evolution of air pollution and the institutional background of environmental governance in China, we examine the development of air pollution control policies from the 1980s and onwards. We show that: (1) The early policies, until 2005, were ineffective at reducing emissions; (2) During 2006-2012, new instruments which interact with political incentives were introduced in the 11th Five-Year Plan, and the national goal of reducing total sulfur dioxide (SO₂) emissions by 10% was achieved. However, regional compound air pollution problems dominated by fine particulate matter (PM 2.5 ) and ground level ozone (O₃) emerged and worsened; (3) After the winter-long PM 2.5 episode in eastern China in 2013, air pollution control policies have been experiencing significant changes on multiple fronts. In this work we analyze the different policy changes, the drivers of changes and key factors influencing the effectiveness of policies in these three stages. Lessons derived from the policy evolution have implications for future studies, as well as further reforming the management scheme towards air quality and health risk oriented directions.

Air Pollution Control Policies in China: A Retrospective and Prospects

PubMed Central

Jin, Yana; Andersson, Henrik; Zhang, Shiqiu

2016-01-01

With China’s significant role on pollution emissions and related health damage, deep and up-to-date understanding of China’s air pollution policies is of worldwide relevance. Based on scientific evidence for the evolution of air pollution and the institutional background of environmental governance in China, we examine the development of air pollution control policies from the 1980s and onwards. We show that: (1) The early policies, until 2005, were ineffective at reducing emissions; (2) During 2006–2012, new instruments which interact with political incentives were introduced in the 11th Five-Year Plan, and the national goal of reducing total sulfur dioxide (SO2) emissions by 10% was achieved. However, regional compound air pollution problems dominated by fine particulate matter (PM2.5) and ground level ozone (O3) emerged and worsened; (3) After the winter-long PM2.5 episode in eastern China in 2013, air pollution control policies have been experiencing significant changes on multiple fronts. In this work we analyze the different policy changes, the drivers of changes and key factors influencing the effectiveness of policies in these three stages. Lessons derived from the policy evolution have implications for future studies, as well as further reforming the management scheme towards air quality and health risk oriented directions. PMID:27941665

[Impact of canopy structural characteristics on inner air temperature and relative humidity of Koelreuteria paniculata community in summer].

PubMed

Qin, Zhong; Li, Zhan-dong; Cheng, Fang-yun; Sha, Hai-feng

2015-06-01

To investigate the diurnal variation of the correlations between the cooling and humidifying effects and canopy structural characteristics of the Koelreuteria paniculata community, the measurements of air temperature, relative humidity, canopy density, leaf area index (LAI) and mean leaf angle (MLA) were performed on calm sunny summer days in the community in Beijing Olympic Forest Park, China. There were significant correlations between the canopy density, LAI and MLA, which affected the cooling and humidifying effects together. The cooling effect reached its maximum by 12:00, whereas the humidifying effect reached its peak at 10:00. Compared with the control open space site, the community appeared to lower the air temperature by 0.43 to 7.53 °C and to increase the relative humidity by 1%-22% during the daytime. However, the cooling and humidifying effects seem to be not effective during the night. The canopy density and LAI were better for determining the cooling and humidifying effects from 9:00 to 12:00. However, these effects were largely controlled only by the canopy density from 12:00 to 14:00 and were significantly correlated with the canopy density and LAI afterwards until 18:00.

Microbiological evaluation of a newly designed dental air-turbine handpiece for anti-cross contaminations.

PubMed

Ohsuka, S; Ohta, M; Masuda, K; Kaneda, T; Ueda, M

1994-01-01

The effectiveness of a newly developed anti-cross contamination device for a dental air-turbine handpiece was tested. The handpiece with or without the anti-cross contamination device was contaminated with two bacterial strains, Staphylococcus aureus and Streptococcus mutans, as well as two bacteriophage strains, T2 and MS2. After contamination with these microorganisms, the handpieces were disinfected with glutaraldehyde or replaced with newly autoclaved ones. Residual microorganisms inside the handpiece or an air/water supply hose line were collected and counted after overnight cultivation. The anti-cross contamination device effectively reduced the contamination level of an air-turbine handpiece to that of the negative control. No microbial contamination in the air/water supply hose line was detected with this device.

Response mechanisms of conifers to air pollutants

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

Matyssek, R.; Reich, P.; Oren, R.

1995-07-01

Conifers are known to respond to SO{sub 2}, O{sub 3}, NO{sub x} and acid deposition. Of these pollutants, O{sub 3} is likely the most widespread and phytotoxic compound, and therefore of great interest to individuals concerned with forest resources Direct biological responses have a toxicological effects on metabolism which can then scale to effects on tree growth and forest ecology, including processes of competition and succession. Air pollution can cause reductions in photosynthesis and stomatal conductance, which are the physiological parameters most rigorously studied for conifers. Some effects air pollutants can have on plants are influenced by the presence ofmore » co-occurring environmental stresses. For example, drought usually reduces vulnerability of plants to air pollution. In addition, air pollution sensitivity may differ among species and with plant/leaf age. Plants may make short-term physiological adjustments to compensate for air pollution or may evolve resistance to air pollution through the processes of selection. Models are necessary to understand how physiological processes, growth processes, and ecological processes are affected by air pollutants. The process of defining the ecological risk that air pollutants pose for coniferous forests requires approaches that exploit existing databases, environmental monitoring of air pollutants and forest resources, experiments with well-defined air pollution treatments and environmental control/monitoring, modeling, predicting air pollution-caused changes in productivity and ecological processes over time and space, and integration of social values.« less

40 CFR 92.1006 - Refueling requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Requirements Applicable to... designed in such a manner so as not to render inoperative or reduce the effectiveness of the controls on...

Biodiesel and Cold Temperature Effects on Speciated Mobile Source Air Toxics from Modern Diesel Trucks

EPA Science Inventory

Speciated volatile organic compounds (VOCs) with a particular focus on mobile source air toxics (MSATs) were measured in diesel exhaust from three heavy-duty trucks equipped with modern aftertreatment technologies. Emissions testing was conducted on a temperature controlled chass...

Biodiesel and Cold Temperature Effect on Speciated Mobile Source Air Toxics from Modern Diesel Trucks

EPA Science Inventory

Speciated volatile organic compounds (VOCs) with a particular focus on mobile source air toxics (MSATs) were measured in diesel exhaust from three heavy-duty trucks equipped with modern aftertreatment technologies. Emissions testing was conducted on a temperature controlled chass...

Experimental Studies of Active and Passive Flow Control Techniques Applied in a Twin Air-Intake

PubMed Central

Joshi, Shrey; Jindal, Aman; Maurya, Shivam P.; Jain, Anuj

2013-01-01

The flow control in twin air-intakes is necessary to improve the performance characteristics, since the flow traveling through curved and diffused paths becomes complex, especially after merging. The paper presents a comparison between two well-known techniques of flow control: active and passive. It presents an effective design of a vortex generator jet (VGJ) and a vane-type passive vortex generator (VG) and uses them in twin air-intake duct in different combinations to establish their effectiveness in improving the performance characteristics. The VGJ is designed to insert flow from side wall at pitch angle of 90 degrees and 45 degrees. Corotating (parallel) and counterrotating (V-shape) are the configuration of vane type VG. It is observed that VGJ has the potential to change the flow pattern drastically as compared to vane-type VG. While the VGJ is directed perpendicular to the side walls of the air-intake at a pitch angle of 90 degree, static pressure recovery is increased by 7.8% and total pressure loss is reduced by 40.7%, which is the best among all other cases tested for VGJ. For bigger-sized VG attached to the side walls of the air-intake, static pressure recovery is increased by 5.3%, but total pressure loss is reduced by only 4.5% as compared to all other cases of VG. PMID:23935422

Humidification and perceived indoor air quality in the office environment.

PubMed Central

Reinikainen, L M; Aunela-Tapola, L; Jaakkola, J J

1997-01-01

OBJECTIVE: To evaluate the effect of humidification on the odour, acceptability, and stuffiness of indoor air. METHODS: In a six period cross over trial at the Pasila Office Center, Helsinki, the air of two wings of the building in turn were ventilated with air of 30%-40% humidity. A third wing served as a non-humidified control area. The quality of indoor air was assessed weekly by a panel containing 18 to 23 members. The intraindividual differences in the ratings for odour, stuffiness, and acceptability between humidified and non-humidified wings were used to assess the effect of humidification. The roles of sex, current smoking, and age as potential effect modifiers were assessed by comparing the mean intraindividual differences in ratings between the groups. RESULTS: Humidified air was found to be more odorous and stuffy (paired t test P = 0.0001) and less acceptable than the non-humidified air (McNemar's test P < 0.001). The differences in odour and stuffiness between humidified and non-humidified air were greater for women and for non-smokers, and greatest differences were in the youngest age group, and least in the oldest age group. The differences were not significant. CONCLUSIONS: An untrained panel of 20 members is able to differentiate a slight malodour and stuffiness in indoor air. The results suggest that steam air humidification decreases the perceived air quality. This effect is strongest in women and young subjects. PMID:9196454

Air Quality and Heart Health: An Emerging Topic for Heart ...

EPA Pesticide Factsheets

Air Quality and Heart Health: An Emerging Topic for Heart Month: Ambient air particle pollution increases short- and long-term cardiovascular morbidity and mortality. Older-people, those with pre-existing heart disease and lung disease and diabetes are at higher risk. Mechanisms are under investigation and are likely related to oxidative stress, inflammation and effects on autonomic control. Improvements in air pollution levels reduce health impacts and increase life expectancy. Reductions of short-term exposure in those at highest risk are predicted to mitigate adverse health effects. EPA regularly evaluates the standards, health risks and issues improved standards when needed. Public health action is needed along with EPA standards to reduce the public health burden of short- and long-term adverse health effects of air pollution. Health risks remain and need to be addressed through integrated efforts of public health, health care, environmental health, individuals and communities. Presented at Webinar for the National Association of Clean Air Agencies, February 2, 2017, Chapel Hill, NC- This webinar provided an update of environmental health information related to the effects of air pollution and heart and blood vessel disease. Such information is critically important for the Clean Air Agencies to understand as it provides the justification of their actions.

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...

40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...

Parametric Studies of Flow Separation using Air Injection

NASA Technical Reports Server (NTRS)

Zhang, Wei

2004-01-01

Boundary Layer separation causes the airfoil to stall and therefore imposes dramatic performance degradation on the airfoil. In recent years, flow separation control has been one of the active research areas in the field of aerodynamics due to its promising performance improvements on the lifting device. These active flow separation control techniques include steady and unsteady air injection as well as suction on the airfoil surface etc. This paper will be focusing on the steady and unsteady air injection on the airfoil. Although wind tunnel experiments revealed that the performance improvements on the airfoil using injection techniques, the details of how the key variables such as air injection slot geometry and air injection angle etc impact the effectiveness of flow separation control via air injection has not been studied. A parametric study of both steady and unsteady air injection active flow control will be the main objective for this summer. For steady injection, the key variables include the slot geometry, orientation, spacing, air injection velocity as well as the injection angle. For unsteady injection, the injection frequency will also be investigated. Key metrics such as lift coefficient, drag coefficient, total pressure loss and total injection mass will be used to measure the effectiveness of the control technique. A design of experiments using the Box-Behnken Design is set up in order to determine how each of the variables affects each of the key metrics. Design of experiment is used so that the number of experimental runs will be at minimum and still be able to predict which variables are the key contributors to the responses. The experiments will then be conducted in the 1ft by 1ft wind tunnel according to the design of experiment settings. The data obtained from the experiments will be imported into JMP, statistical software, to generate sets of response surface equations which represent the statistical empirical model for each of the metrics as a function of the key variables. Next, the variables such as the slot geometry can be optimized using the build-in optimizer within JMP. Finally, a wind tunnel testing will be conducted using the optimized slot geometry and other key variables to verify the empirical statistical model. The long term goal for this effort is to assess the impacts of active flow control using air injection at system level as one of the task plan included in the NASAs URETI program with Georgia Institute of Technology.

Case study of odor and indoor air quality assessment in the dewatering building at the Stickney Water Reclamation Plant.

PubMed

Sharma, Manju; O'Connell, Susan; Garelli, Brett; Sattayatewa, Chakkrid; Moschandreas, Demetrios; Pagilla, Krishna

2012-01-01

Indoor air quality (IAQ) and odors were determined using sampling/monitoring, measurement, and modeling methods in a large dewatering building at a very large water reclamation plant. The ultimate goal was to determine control strategies to reduce the sensory impacts on the workforce and achieve odor reduction within the building. Study approaches included: (1) investigation of air mixing by using CO(2) as an indicator, (2) measurement of airflow capacity of ventilation fans, (3) measurement of odors and odorants, (4) development of statistical and IAQ models, and (5) recommendation of control strategies. The results showed that air quality in the building complies with occupational safety and health guidelines; however, nuisance odors that can increase stress and productivity loss still persist. Excess roof fan capacity induced odor dispersion to the upper levels. Lack of a local air exhaust system of sufficient capacity and optimum design was found to be the contributor to occasional less than adequate indoor air quality and odors. Overall, air ventilation rate in the building has less effect on persistence of odors in the building. Odor/odorant emission rates from centrifuge drops were approximately 100 times higher than those from the open conveyors. Based on measurements and modeling, the key control strategies recommended include increasing local air exhaust system capacity and relocation of exhaust hoods closer to the centrifuge drops.

Hospital admissions for ischemic stroke: does long-term exposure to air pollution interact with major risk factors?

PubMed

Oudin, Anna; Strömberg, Ulf; Jakobsson, Kristina; Stroh, Emilie; Lindgren, Arne G; Norrving, Bo; Pessah-Rasmussen, Hélène; Engström, Gunnar; Björk, Jonas

2011-01-01

The aim was to investigate whether the effects of major risk factors for ischemic stroke were modified by long-term exposure to air pollution in Scania, southern Sweden. Cases were defined as first-ever ischemic strokes in patients born between 1923 and 1965 during 2001-2006 (n = 7,244). Data were collected from The Swedish National Stroke Register (Riks-stroke) and the Malmö and Lund Stroke Registers. Population controls were matched on age and sex. Modeled outdoor annual mean NO(x) concentrations were used as proxy for long-term exposure to air pollution. Heterogeneity across NO(x) categories was tested for smoking, hypertension, diabetes mellitus, atrial fibrillation and physical inactivity. Data were analyzed as case-control data and to some extent as case-only data, with logistic regression analysis. The case-control odds ratios for ischemic stroke in association with diabetes were 1.3 [95% confidence interval (CI): 1.1-1.6] and 2.0 (95% CI: 1.2-3.4) in the lowest and highest NO(x) category, respectively (p value for testing heterogeneity across the categories = 0.056). The case-only approach gave further support for the risk associated with diabetes to increase with NO(x) (p for trend = 0.033). We observed no main effect of mean NO(x) or any conclusive effect modifications between NO(x) and smoking, hypertension, atrial fibrillation or physical inactivity. In a low-level air pollution area, the risk for ischemic stroke associated with diabetes seemed to increase with long-term exposure to air pollution. Copyright © 2010 S. Karger AG, Basel.

Impact of emission control on regional air quality in the Pearl Delta River region, southern China

NASA Astrophysics Data System (ADS)

Wang, N.; Xuejiao, D.

2017-12-01

The Pearl River Delta (PRD) in China has been suffering from air quality issues and the government has implemented a series of strategies in controlling emissions. In an attempt to provide scientific support for improving air quality, the paper investigates the concerning past-to-present air quality data and assesses air quality resulting from emission control. Statistical data revealed that energy consumption doubled from 2004 to 20014 and vehicle usage increased significantly from 2006 to 2014. Due to the effect of control efforts, primary emission of SO2, NOx and PM2.5 decreased resulting in ambient concentrations of SO2, NO2 and PM10 decreased by 66%, 20% and 24%, respectively. However, O3 increased 19% because of the increase of VOC emission. A chemical transport model, the Community Multi-scale Air Quality, was employed to evaluate the responses of nitrate, ammonium, SOA, PM2.5 and O3 to changes in NOx, VOC and NH3 emissions. Three scenarios, a baseline scenario, a CAP scenario (control strength followed as past tendency), and a REF scenario (strict control referred to latest policy and plans), were conducted to investigate the responses and mechanisms. NOx controlling scenarios showed that NOx, nitrate and PM2.5 reduced by 1.8%, 0.7% and 0.2% under CAP and reduced by 7.2%, 1.8% and 0.3% under REF, respectively. The results indicated that reducing NOx emission caused the increase of atmospheric oxidizability, which might result in a compensation of PM2.5 due to the increase of nitrate or sulfate. NH3 controlling scenarios showed that nitrate was sensitive to NH3 emission in PRD, with nitrate decreased by 0 - 10.6% and 0 - 48% under CAP and REF, respectively. Since controlling NH3 emissions not only reduced ammonium but also significantly reduced nitrate, the implement of NH3 controlling strategy was highly suggested. The VOC scenarios revealed that though SOA was not the major component of PM2.5, controlling VOC emission might take effect in southwestern PRD where photochemical pollution usually occurred. Last but not least, the responses of O3 indicated that the PRD was generally VOC-sensitive, while the regime turned to NOx-sensitive in the afternoon, therefore controlling VOC emission could reduce the overall O3 and controlling NOx emission in the afternoon could reduce peak O3.

Cost-effectiveness of forced air warming during sedation in the cardiac catheterisation laboratory.

PubMed

Conway, Aaron; Duff, Jed; Sutherland, Joanna

2018-05-13

To determine the cost-effectiveness of forced air warming during sedation in a cardiac catheterisation laboratory. Forced air warming improves thermal comfort in comparison with standard care. It is not known whether the extra costs required for forced air warming are good value. Cost-effectiveness analysis alongside a randomised controlled trial conducted in 2016-2017. A cost-effectiveness analysis was undertaken using Monte Carlo simulations from input distributions to estimate costs and effects associated with using forced air warming to reduce risk of thermal discomfort for patients receiving sedation in a cardiac catheterisation laboratory. A range of willingness to pay threshold values were tested with results plotted on a cost-effectiveness acceptability curve. Costs were calculated in Australian currency ($AUD). Estimated total costs were $5.21 (SD 3.26) higher per patient for forced air warming in comparison to standard care. Estimated probability of success (rating of thermal comfort) was 0.16 (0.06) higher for forced air warming. Forced air warming becomes more likely to result in a net benefit than standard care at a willingness to pay threshold of $34. Forced air warming could be considered cost-effective for procedures performed with sedation in a cardiac catheterisation laboratory if the extra cost of an incremental gain in thermal comfort is less than the decision maker's willingness to pay for it. Therefore, those responsible for decision-making regarding use of forced air warming in the cardiac catheterisation laboratory can use results of our model to decide if it represents good value for their organisation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effects of noise exposure on performance of a simulated radar task.

DOT National Transportation Integrated Search

1979-11-01

The present study examined the effect of noise (radar control room sounds, 80 dBA) on the ability to sustain attention to a complex monitoring task. The visual display was designed to resemble that of a highly automated air traffic control radar syst...

Proposed Rule for Control of Air Pollution From New Motor Vehicles: Proposed Heavy-Duty Engine and Vehicle Standards and Highway Diesel Fuel Sulfur Control Requirements

EPA Pesticide Factsheets

Rule summary, CFR citations and additional resources concerning proposed new emission standards that will begin to take effect in 2007 and corresponding diesel fuel requirements that take effect in 2006.

Department of Defense Air Traffic Control and Airspace Management Systems

DTIC Science & Technology

1989-08-08

service. The potential near-term impacts of incompatible and non- interoperable systems on the Air Force are described in terms of safety and...impacts of incompatible and non-interoperable systems on the Air Force are described in terms of safety and operational effectiveness and probable...derogation of safety , from the standpoint of aircraft collision avoidance, is probable where service specific systems are operating in adjacent or

Application of automobile emission control technology to light piston aircraft engines

NASA Technical Reports Server (NTRS)

Tripp, D.; Kittredge, G.

1976-01-01

The possibility was evaluated for achieving the EPA Standards for HC and CO emissions through the use of air-fuel ratio enleanment at selected power modes combined with improved air-fuel mixture preparation, and in some cases improved cooling. Air injection was also an effective approach for the reduction of HC and CO, particularly when combined with exhaust heat conservation techniques such as exhaust port liners.

Meta-Prediction of the Effect of Methylenetetrahydrofolate Reductase Polymorphisms and Air Pollution on Alzheimer's Disease Risk.

PubMed

Wu, Suh-Mian; Chen, Zhao-Feng; Young, Lufei; Shiao, S Pamela K

2017-01-11

Background : Alzheimer's disease (AD) is a significant public health issue. AD has been linked with methylenetetrahydrofolate reductase ( MTHFR ) C677T polymorphism, but the findings have been inconsistent. The purpose of this meta-predictive analysis is to examine the associations between MTHFR polymorphisms and epigenetic factors, including air pollution, with AD risk using big data analytics approaches. Methods and Results : Forty-three studies (44 groups) were identified by searching various databases. MTHFR C677T TT and CT genotypes had significant associations with AD risk in all racial populations (RR = 1.13, p = 0.0047; and RR = 1.12, p < 0.0001 respectively). Meta-predictive analysis showed significant increases of percentages of MTHFR C677T polymorphism with increased air pollution levels in both AD case group and control group ( p = 0.0021-0.0457); with higher percentages of TT and CT genotypes in the AD case group than that in the control group with increased air pollution levels. Conclusions : The impact of MTHFR C677T polymorphism on susceptibility to AD was modified by level of air pollution. Future studies are needed to further examine the effects of gene-environment interactions including air pollution on AD risk for world populations.

Meta-Prediction of the Effect of Methylenetetrahydrofolate Reductase Polymorphisms and Air Pollution on Alzheimer’s Disease Risk

PubMed Central

Wu, Suh-Mian; Chen, Zhao-Feng; Young, Lufei; Shiao, S. Pamela K.

2017-01-01

Background: Alzheimer’s disease (AD) is a significant public health issue. AD has been linked with methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, but the findings have been inconsistent. The purpose of this meta-predictive analysis is to examine the associations between MTHFR polymorphisms and epigenetic factors, including air pollution, with AD risk using big data analytics approaches. Methods and Results: Forty-three studies (44 groups) were identified by searching various databases. MTHFR C677T TT and CT genotypes had significant associations with AD risk in all racial populations (RR = 1.13, p = 0.0047; and RR = 1.12, p < 0.0001 respectively). Meta-predictive analysis showed significant increases of percentages of MTHFR C677T polymorphism with increased air pollution levels in both AD case group and control group (p = 0.0021–0.0457); with higher percentages of TT and CT genotypes in the AD case group than that in the control group with increased air pollution levels. Conclusions: The impact of MTHFR C677T polymorphism on susceptibility to AD was modified by level of air pollution. Future studies are needed to further examine the effects of gene-environment interactions including air pollution on AD risk for world populations. PMID:28085050

Marginal abatement cost curve for nitrogen oxides incorporating controls, renewable electricity, energy efficiency, and fuel switching.

PubMed

Loughlin, Daniel H; Macpherson, Alexander J; Kaufman, Katherine R; Keaveny, Brian N

2017-10-01

A marginal abatement cost curve (MACC) traces out the relationship between the quantity of pollution abated and the marginal cost of abating each additional unit. In the context of air quality management, MACCs are typically developed by sorting control technologies by their relative cost-effectiveness. Other potentially important abatement measures such as renewable electricity, energy efficiency, and fuel switching (RE/EE/FS) are often not incorporated into MACCs, as it is difficult to quantify their costs and abatement potential. In this paper, a U.S. energy system model is used to develop a MACC for nitrogen oxides (NO x ) that incorporates both traditional controls and these additional measures. The MACC is decomposed by sector, and the relative cost-effectiveness of RE/EE/FS and traditional controls are compared. RE/EE/FS are shown to have the potential to increase emission reductions beyond what is possible when applying traditional controls alone. Furthermore, a portion of RE/EE/FS appear to be cost-competitive with traditional controls. Renewable electricity, energy efficiency, and fuel switching can be cost-competitive with traditional air pollutant controls for abating air pollutant emissions. The application of renewable electricity, energy efficiency, and fuel switching is also shown to have the potential to increase emission reductions beyond what is possible when applying traditional controls alone.

How to reach haze control targets by air pollutants emission reduction in the Beijing-Tianjin-Hebei region of China?

PubMed

Xu, Feng; Xiang, Nan; Higano, Yoshiro

2017-01-01

Currently, Haze is one of the greatest environmental problems with serious impacts on human health in China, especially in capital region (Beijing-Tianjin-Hebei region). To alleviate this problem, the Chinese government introduced a National Air Pollution Control Action Plan (NAPCAP) with air pollutants reduction targets by 2017. However, there is doubt whether these targets can be achieved once the plan is implemented. In this work, the effectiveness of NAPCAP is analyzed by developing models of the statistical relationship between PM2.5 concentrations and air pollutant emissions (SO2, NOx, smoke and dust), while taking into account wind and neighboring transfer impacts. The model can also identify ways of calculating the intended emission levels in the Beijing-Tianjin-Hebei area. The results indicate that haze concentration control targets will not be attained by following the NAPCAP, and that the amount of progress needed to meet the targets is unrealistic. A more appropriate approach to reducing air emissions is proposed, which addresses joint regional efforts.

40 CFR 60.2141 - By what date must I conduct the initial air pollution control device inspection?

Code of Federal Regulations, 2011 CFR

2011-07-01

... air pollution control device inspection? 60.2141 Section 60.2141 Protection of Environment... initial air pollution control device inspection? (a) The initial air pollution control device inspection... startup. (b) Within 10 operating days following an air pollution control device inspection, all necessary...

40 CFR 60.2141 - By what date must I conduct the initial air pollution control device inspection?

Code of Federal Regulations, 2012 CFR

2012-07-01

... air pollution control device inspection? 60.2141 Section 60.2141 Protection of Environment... initial air pollution control device inspection? (a) The initial air pollution control device inspection... startup. (b) Within 10 operating days following an air pollution control device inspection, all necessary...

Effect of Dynamic Sector Boundary Changes on Air Traffic Controllers

NASA Technical Reports Server (NTRS)

Jung, Jaewoo; Lee, Paul; Kessell, Angela; Homola, Jeff; Zelinski, Shannon

2010-01-01

The effect of dynamic sector boundary changes on air traffic controller workload was investigated with data from a human-in-the-loop simulation. Multiple boundary changes were made during simulated operations, and controller rating of workload was recorded. Analysis of these data showed an increase of 16.9% in controller workload due to boundary changes. This increased workload was correlated with the number of aircraft handoffs and change in sector volume. There was also a 12.7% increase in average workload due to the changed sector design after boundary changes. This increase was correlated to traffic flow crossing points getting closer to sector boundaries and an increase in the number of flights with short dwell time in a sector. This study has identified some of the factors that affect controller workload when sector boundaries are changed, but more research is needed to better understand their relationships.

Methodology for determination and use of the no-escape envelope of an air-to-air-missile

NASA Technical Reports Server (NTRS)

Neuman, Frank

1988-01-01

A large gap exists between optimal control and differential-game theory and their applications. The purpose of this paper is to show how this gap may be bridged. Missile-avoidance of realistically simulated infrared heat-seeking, fire-and-forget missile is studied. In detailed simulations, sweeping out the discretized initial condition space, avoidance methods based on pilot experience are combined with those based on simplified optimal control analysis to derive an approximation to the no-escape missile envelopes. The detailed missile equations and no-escape envelopes were then incorporated into an existing piloted simulation of air-to-air combat to generate missile firing decisions as well as missile avoidance commands. The use of these envelopes was found to be effective in both functions.

40 CFR 81.76 - State of Hawaii 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 State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air Quality...

40 CFR 81.76 - State of Hawaii 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 State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air Quality...

40 CFR 81.76 - State of Hawaii 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 State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air Quality...

40 CFR 81.76 - State of Hawaii 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 State of Hawaii Air Quality Control... PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.76 State of Hawaii Air Quality Control Region. The State of Hawaii Air Quality...

Fuzzy logic control of rotating drum bioreactor for improved production of amylase and protease enzymes by Aspergillus oryzae in solid-state fermentation.

PubMed

Sukumprasertsri, Monton; Unrean, Pornkamol; Pimsamarn, Jindarat; Kitsubun, Panit; Tongta, Anan

2013-03-01

In this study, we compared the performance of two control systems, fuzzy logic control (FLC) and conventional control (CC). The control systems were applied for controlling temperature and substrate moisture content in a solidstate fermentation for the biosynthesis of amylase and protease enzymes by Aspergillus oryzae. The fermentation process was achieved in a 200 L rotating drum bioreactor. Three factors affecting temperature and moisture content in the solid-state fermentation were considered. They were inlet air velocity, speed of the rotating drum bioreactor, and spray water addition. The fuzzy logic control system was designed using four input variables: air velocity, substrate temperature, fermentation time, and rotation speed. The temperature was controlled by two variables, inlet air velocity and rotational speed of bioreactor, while the moisture content was controlled by spray water. Experimental results confirmed that the FLC system could effectively control the temperature and moisture content of substrate better than the CC system, resulting in an increased enzyme production by A. oryzae. Thus, the fuzzy logic control is a promising control system that can be applied for enhanced production of enzymes in solidstate fermentation.

Tobacco Control Laws and Pediatric Asthma.

PubMed

Hatoun, Jonathan; Davis-Plourde, Kendra; Penti, Brian; Cabral, Howard; Kazis, Lewis

2018-01-01

Exposure to environmental tobacco smoke increases pediatric asthma severity. Strict, state-level tobacco control reduces smoking. The Child Asthma Call-Back Survey (Child ACBS) is a nationally representative survey of the guardians of children with asthma. The American Lung Association's annual State of Tobacco Control report grades tobacco control laws in each state including a tax grade (cigarette excise tax relative to the national mean), and a smoke-free air grade (number of locations where smoking is prohibited). We joined Child ACBS data from 2006 to 2010 with corresponding state and year tobacco grades. In the primary analysis, we investigated the effect of state tax grades on a child's asthma severity by using a logistic regression model adjusting for year. A secondary analysis assessed the impact of smoke-free air grades on in-home smoking. Our analysis included 12 860 Child ACBS interviews from 35 states over 5 years, representing over 24 million individuals. We merged 112 unique State of Tobacco Control grades with patient data by state and year. A higher tax grade was associated with reduced severity (adjusted odds ratio = 1.40; P = .007, 95% confidence interval: 1.10-1.80). A better smoke-free air grade was not associated with decreased in-home smoking after adjusting for confounding by income and type of residence. A stronger tobacco tax is associated with reduced asthma severity. Further study is needed to determine the effect of smoke-free air laws on in-home environmental. This work supports ongoing efforts to strengthen tobacco control through federal and state regulations. Copyright © 2018 by the American Academy of Pediatrics.

The effect of air entrapment on the performance of squeeze film dampers: Experiments and analysis

NASA Astrophysics Data System (ADS)

Diaz Briceno, Sergio Enrique

Squeeze film dampers (SFDs) are an effective means to introduce the required damping in rotor-bearing systems. They are a standard application in jet engines and are commonly used in industrial compressors. Yet, lack of understanding of their operation has confined the design of SFDs to a costly trial and error process based on prior experience. The main factor deterring the success of analytical models for the prediction of SFDs' performance lays on the modeling of the dynamic film rupture. Usually, the cavitation models developed for journal bearings are applied to SFDs. Yet, the characteristic motion of the SFD results in the entrapment of air into the oil film, thus producing a bubbly mixture that can not be represented by these models. In this work, an extensive experimental study establishes qualitatively and---for the first time---quantitatively the differences between operation with vapor cavitation and with air entrainment. The experiments show that most operating conditions lead to air entrainment and demonstrate the paramount effect it has on the performance of SFDs, evidencing the limitation of currently available models. Further experiments address the operation of SFDs with controlled bubbly mixtures. These experiments bolster the possibility of modeling air entrapment by representing the lubricant as a homogeneous mixture of air and oil and provide a reliable data base for benchmarking such a model. An analytical model is developed based on a homogeneous mixture assumption and where the bubbles are described by the Rayleigh-Plesset equation. Good agreement is obtained between this model and the measurements performed in the SFD operating with controlled mixtures. A complementary analytical model is devised to estimate the amount of air entrained from the balance of axial flows in the film. A combination of the analytical models for prediction of the air volume fraction and of the hydrodynamic pressures renders promising results for prediction of the performance of SFDs with freely entrained air. The results of this work are of immediate engineering applicability. Furthermore, they represent a firm step to advance the understanding on the effects of air entrapment in the performance of SFD.

STRATEGIES TO REDUCE EXPOSURE TO TRAFFIC-RELATED AIR POLLUTION AT THE LOCAL LEVEL

EPA Science Inventory

As public health concerns for populations living, working and going to school near high-traffic roadways have increased, so have the need to identify and implement air pollution control strategies effective at the local level. While strategies implemented at the federal and stat...

77 FR 66945 - Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Reasonably...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-08

... and Promulgation of Air Quality Implementation Plans; New Hampshire; Reasonably Available Control... Implementation Plan (SIP) revision submitted by the State of New Hampshire. The revision establishes Reasonably... intended effect of this action is to approve these requirements into the New Hampshire SIP. This action is...

Early Warning Report: Use of Contractors to Conduct Clean Air Act Risk Management Program Inspections in Certain States Goes Against Court Decisions

EPA Pesticide Factsheets

Report #12-P-0376, March 28, 2012. The OIG is currently evaluating whether the EPA has adequate management controls for ensuring the effectiveness of its Clean Air Act (CAA) Section 112(r) risk management program inspections.

Formaldehyde and acetaldehyde exposure mitigation in US residences: In-home measurements of ventilation control and source control

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

Hult, Erin L.; Willem, Henry; Price, Phillip N.

2014-10-01

Measurements were taken in new US residences to assess the extent to which ventilation and source control can mitigate formaldehyde exposure. Increasing ventilation consistently lowered indoor formaldehyde concentrations. However, at a reference air exchange rate of 0.35 h -1, increasing ventilation was up to 60% less effective than would be predicted if the emission rate were constant. This is consistent with formaldehyde emission rates decreasing as air concentrations increase, as observed in chamber studies. In contrast, measurements suggest acetaldehyde emission was independent of ventilation rate. To evaluate the effectiveness of source control, formaldehyde concentrations were measured in Leadership in Energymore » and Environmental Design (LEED) certified/Indoor airPLUS homes constructed with materials certified to have low emission rates of volatile organic compounds (VOC). At a reference air exchange rate of 0.35 h -1, and adjusting for home age, temperature and relative humidity, formaldehyde concentrations in homes built with low-VOC materials were 42% lower on average than in reference new homes with conventional building materials. Without adjustment, concentrations were 27% lower in the low-VOC homes. The mean and standard deviation of formaldehyde concentration were 33 μg m-3 and 22 μg m -3 for low-VOC homes and 45 μg m -3 and 30 μg m -3 for conventional.« less

Urban air pollution in megacities of the world

NASA Astrophysics Data System (ADS)

Mage, David; Ozolins, Guntis; Peterson, Peter; Webster, Anthony; Orthofer, Rudi; Vandeweerd, Veerle; Gwynne, Michael

Urban air pollution is a major environmental problem in the developing countries of the world. WHO and UNEP created an air pollution monitoring network as part of the Global Environment Monitoring System. This network now covers over 50 cities in 35 developing and developed countries throughout the world. The analyses of the data reported by the network over the past 15-20 yr indicate that the lessons of the prior experiences in the developed countries (U.S.A., U.K.) have not been learned. A study of air pollution in 20 of the 24 megacities of the world (over 10 million people by year 2000) shows that ambient air pollution concentrations are at levels where serious health effects are reported. The expected rise of population in the next century, mainly in the developing countries with a lack of capital for air pollution control, means that there is a great potential that conditions will worsen in many more cities that will reach megacity status. This paper maps the potential for air pollution that cities will experience in the future unless control strategies are developed and implemented during the next several decades.

Roles of Meteorology in Changes of Air Pollutants Concentrations in China from 2010 to 2015

NASA Astrophysics Data System (ADS)

Wang, P.; Kota, S. H.; Hu, J.; Ying, Q.; Zhang, H.

2017-12-01

Tremendous efforts have been made to control the severe air pollution in China in recent years. However, no significant improvement was observed according to annual fine particulate matter (PM2.5) concentrations and the concentrations in severe air pollution events in winter. This is partially due to the role of meteorology, which affects the emission, transport, transformation, and deposition of air pollutants. In this study, simulation of air pollutants over China was conducted for six years from 2010 to 2015 with constant anthropogenic emissions to verify the changes of air pollutants due to meteorology changes only. Model performance was validated by comparing with meteorological observations and air pollutants measures from various sources. Four different regions/cities were selected to understand the changes in wind, mixing layer height, temperature, and relative humanity at different seasons. The changes in concentrations of pollutants including PM2.5 and its chemical components and ozone were analyzed and associated with meteorological changes. This study would provide information for designing effective control strategies in different areas with the consideration of meteorological and climate changes.

Characteristics of an aerosol photometer while automatically controlling chamber dilution-air flow rate.

PubMed

O'Shaughnessy, P T; Hemenway, D R

2000-10-01

Trials were conducted to determine those factors that affect the accuracy of a direct-reading aerosol photometer when automatically controlling airflow rate within an exposure chamber to regulate airborne dust concentrations. Photometer response was affected by a shift in the aerosol size distribution caused by changes in chamber flow rate. In addition to a dilution effect, flow rate also determined the relative amount of aerosol lost to sedimentation within the chamber. Additional calculations were added to a computer control algorithm to compensate for these effects when attempting to automatically regulate flow based on a proportional-integral-derivative (PID) feedback control algorithm. A comparison between PID-controlled trials and those performed with a constant generator output rate and dilution-air flow rate demonstrated that there was no significant decrease in photometer accuracy despite the many changes in flow rate produced when using PID control. Likewise, the PID-controlled trials produced chamber aerosol concentrations within 1% of a desired level.

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

40 CFR 63.943 - Standards-Surface impoundment vented to control device.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the surface impoundment; the effects of outdoor exposure to wind, moisture, and sunlight; and the... shall inspect and monitor the air emission control equipment in accordance with the procedures specified...

Thermal effects on bacterial bioaerosols in continuous air flow.

PubMed

Jung, Jae Hee; Lee, Jung Eun; Kim, Sang Soo

2009-08-01

Exposure to bacterial bioaerosols can have adverse effects on health, such as infectious diseases, acute toxic effects, and allergies. The search for ways of preventing and curing the harmful effects of bacterial bioaerosols has created a strong demand for the study and development of an efficient method of controlling bioaerosols. We investigated the thermal effects on bacterial bioaerosols of Escherichia coli and Bacillus subtilis by using a thermal electric heating system in continuous air flow. The bacterial bioaerosols were exposed to a surrounding temperature that ranged from 20 degrees C to 700 degrees C for about 0.3 s. Both E. coli and B. subtilis vegetative cells were rendered more than 99.9% inactive at 160 degrees C and 350 degrees C of wall temperature of the quartz tube, respectively. Although the data on bacterial injury showed that the bacteria tended to sustain greater damage as the surrounding temperature increased, Gram-negative E. coli was highly sensitive to structural injury but Gram-positive B. subtilis was slightly more sensitive to metabolic injury. In addition, the inactivation of E. coli endotoxins was found to range from 9.2% (at 200 degrees C) to 82.0% (at 700 degrees C). However, the particle size distribution and morphology of both bacterial bioaerosols were maintained, despite exposure to a surrounding temperature of 700 degrees C. Our results show that thermal heating in a continuous air flow can be used with short exposure time to control bacterial bioaerosols by rendering the bacteria and endotoxins to a large extent inactive. This result could also be useful for developing more effective thermal treatment strategies for use in air purification or sterilization systems to control bioaerosols.

Health effects of metropolitan traffic-related air pollutants on street vendors

NASA Astrophysics Data System (ADS)

Kongtip, P.; Thongsuk, W.; Yoosook, W.; Chantanakul, S.

Traffic-related air pollutants are a commonly important source of air pollution. Research on the effects of multiple traffic-related air pollutants on street vendors is scarce. This study evaluated the health effect of traffic-related air pollutants in street vendors. It was designed as a panel study, covering 61 d of data collection, on the daily concentration of air pollutants and daily percentage of respiratory and other health symptoms reported. An adjusted odds ratio was used to estimate the risk of developing respiratory and other adverse health symptoms for street vendors exposed to multiple air pollutants, fine particulate (PM 2.5), nitrogen dioxide (NO 2), ozone (O 3), carbon monoxide (CO) and total volatile organic chemicals (VOCs), after controlling for confounding factors. In the first model, significant associations were found with the adjusted odds ratios of 1.022 and 1.027 for eye irritation and dizziness for PM 2.5 respectively. The adjusted odds ratio of total VOCs was 1.381 for phlegm, 4.840 for chest tightness and 1.429 for upper respiratory symptoms, and the adjusted odds ratio for CO was 1.748 for a sore throat and 1.880 for a cold and 1.655 for a cough. In the second model, the effect of PM 2.5, total VOCs and CO gave a slightly lower effect with the symptoms. The results clearly show the health effects of traffic-related air pollutants on street vendors, and imply suggestions about how to reduce exposure of street vendors.

News focus: Report on state and local air toxics regulatory strategies published by STAPPA/ALAPCO (State and Territorial Air Pollution Program Administrators/Association of Local Air Pollution Control Officials)

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

Not Available

1989-12-01

The report is entitled Toxic Air Pollutants: State and Local Regulatory Strategies - 1989. The 364-page report is the result of a survey of state and local air pollution control agencies, which solicited information on their programs to control air toxics. According to the survey, every state currently has a program to address emissions of air toxics. Additionally, 27 of the 40 local agencies that responded to the survey have, or are developing, air toxics programs. The strategies employed by state and local agencies vary widely, including control technology requirements, risk assessment, acceptable ambient guidelines, or a combination of thesemore » approaches. This is a report summarizing the air toxics control programs currently implemented (or under development) by state and local air pollution control agencies throughout the US. The report is based upon a survey of all 50 states and 220 local air pollution control agencies conducted by the State and Territorial Air Pollution Program Administrators (STAPPA) and the Association of Local Air Pollution Control Officials (ALAPCO). This survey updates one published five years earlier.« less

40 CFR 81.99 - New Mexico Southern Border Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Designation of Air Quality Control Regions § 81.99 New Mexico Southern Border Intrastate Air Quality Control Region. The Arizona-New Mexico Southern Border Interstate Air Quality Control Region has been renamed the New Mexico Southern Border Intrastate Air Quality Control Region and has been revised to consist of...

40 CFR 60.2151 - By what date must I conduct the annual air pollution control device inspection?

Code of Federal Regulations, 2011 CFR

2011-07-01

... air pollution control device inspection? 60.2151 Section 60.2151 Protection of Environment... annual air pollution control device inspection? On an annual basis (no more than 12 months following the previous annual air pollution control device inspection), you must complete the air pollution control...

40 CFR 60.2151 - By what date must I conduct the annual air pollution control device inspection?

Code of Federal Regulations, 2012 CFR

2012-07-01

... air pollution control device inspection? 60.2151 Section 60.2151 Protection of Environment... annual air pollution control device inspection? On an annual basis (no more than 12 months following the previous annual air pollution control device inspection), you must complete the air pollution control...

Effectiveness Through Control: Centralized Execution in Air Mobility Operations

DTIC Science & Technology

2013-03-01

decentralized execution, as “the delegation of authority to designated lower-level commanders and other tactical-level decision makers to achieve effective span...asset “into a flying hospital of sorts with cardiac monitors, defibrillators , intubation devices, litters and various supplies to sustain many types... designated , versus dedicated airlift. A 2006 Air Force Magazine article described the flexibility of this concept, highlighting “When an injured service

Feasibility of Reburning for Controlling NOx Emissions from Air Force Jet Engine Test Cells

DTIC Science & Technology

1989-06-01

the engine exhaust by the augmenter air. For this reason, it is important to examine the effect of inlet NOX concentration on achieved reduction...Schedule at Tinker AFB .... ......... 8 3 Typical Nonafterburning Turbine Engine Emission Trends. . 9 4 Temperature of Diluted Exhaust J-79 Engine ... Exhaust Temperature on Reburner NOX Reduction .......... ......................... . 43 24 Effect of Exhaust Gas Inlet Flow Rate on Reburner NOx

Supplement to the Second Addendum (1986) to Air Quality Criteria for Particulate Matter and Sulfur Oxides (1982): Assessment of New Findings on Sulfur Dioxide and Acute Exposure Health Effects in Asthmatic Individuals (1994)

EPA Science Inventory

The present Supplement to the Second Addendum (1986) to the document Air Quality Criteria for Particulate Matter and Sulfur Oxides (1982) focuses on evaluation of newly available controlled human exposure studies of acute (a\\1h) sulfur dioxide (SO2) exposure effects on pulmonary ...

An Integrated Framework for Multipollutant Air Quality Management and Its Application in Georgia

NASA Astrophysics Data System (ADS)

Cohan, Daniel S.; Boylan, James W.; Marmur, Amit; Khan, Maudood N.

2007-10-01

Air protection agencies in the United States increasingly confront non-attainment of air quality standards for multiple pollutants sharing interrelated emission origins. Traditional approaches to attainment planning face important limitations that are magnified in the multipollutant context. Recognizing those limitations, the Georgia Environmental Protection Division has adopted an integrated framework to address ozone, fine particulate matter, and regional haze in the state. Rather than applying atmospheric modeling merely as a final check of an overall strategy, photochemical sensitivity analysis is conducted upfront to compare the effectiveness of controlling various precursor emission species and source regions. Emerging software enables the modeling of health benefits and associated economic valuations resulting from air pollution control. Photochemical sensitivity and health benefits analyses, applied together with traditional cost and feasibility assessments, provide a more comprehensive characterization of the implications of various control options. The fuller characterization both informs the selection of control options and facilitates the communication of impacts to affected stakeholders and the public. Although the integrated framework represents a clear improvement over previous attainment-planning efforts, key remaining shortcomings are also discussed.

An integrated framework for multipollutant air quality management and its application in Georgia.

PubMed

Cohan, Daniel S; Boylan, James W; Marmur, Amit; Khan, Maudood N

2007-10-01

Air protection agencies in the United States increasingly confront non-attainment of air quality standards for multiple pollutants sharing interrelated emission origins. Traditional approaches to attainment planning face important limitations that are magnified in the multipollutant context. Recognizing those limitations, the Georgia Environmental Protection Division has adopted an integrated framework to address ozone, fine particulate matter, and regional haze in the state. Rather than applying atmospheric modeling merely as a final check of an overall strategy, photochemical sensitivity analysis is conducted upfront to compare the effectiveness of controlling various precursor emission species and source regions. Emerging software enables the modeling of health benefits and associated economic valuations resulting from air pollution control. Photochemical sensitivity and health benefits analyses, applied together with traditional cost and feasibility assessments, provide a more comprehensive characterization of the implications of various control options. The fuller characterization both informs the selection of control options and facilitates the communication of impacts to affected stakeholders and the public. Although the integrated framework represents a clear improvement over previous attainment-planning efforts, key remaining shortcomings are also discussed.

High-temperature controlled atmosphere for post-harvest control of Indian meal moth (Lepidoptera: Pyralidae) on preserved flowers.

PubMed

Sauer, Jodi A; Shelton, Mark D

2002-10-01

High carbon dioxide atmospheres combined with high temperature were effective for controlling Indian meal moth, Plodia interpunctella (Hübner) pupae. Pupae were exposed to atmospheres of 60, 80, or 98% carbon dioxide (CO2) in nitrogen (N2), or 60 or 80% CO2 in air at temperatures of 26.7 degrees C or 32.2 degrees C and 60% RH. Controlled atmosphere treatments at 32.2 degrees C controlled pupae faster than the same treatments at the lower temperature. At both temperatures high CO2 concentration treatments combined with nitrogen killed pupae faster than high CO2 concentration treatments combined with air. Exposure to 80% carbon dioxide mixed with nitrogen was the most effective treatment causing 100% mortality in 12 h at 32.2 degrees C and 93.3% mortality in 18 h at 26.6 degrees C. High-temperature controlled atmosphere treatments had no adverse effects on quality of two preserved floral products, Limonium sinuatum (L.) and Gypsophila elegans (Bieb.), tested for 12, 18, and 24 h according to industry standards.