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This study characterizes the combustion of paper and sewage sludge in a pilot-scale fluidized bed. The highest temperature during combustion within the system was found at the surface of the fluidized bed. Paper sludge containing roughly 59.8% water was burned without auxiliary fuel, but auxiliary fuel was required to incinerate the sewage sludge, which contained about 79.3% water. The stability of operation was monitored based on the average pressure and the standard deviation of pressure fluctuations. The average pressure at the surface of the fluidized bed decreased as the sludge feed rate increased. However, the standard deviation of pressure fluctuations increased as the sludge feed rate increased. Finally, carbon monoxide (CO) emissions decreased as oxygen content increased in the flue gas, and nitrogen oxide (NOx) emissions were also tied with oxygen content. [ABSTRACT FROM AUTHOR]

Data on the concentrations of non-methane hydrocarbons (NMHC), nitrogen oxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO), and meteorological parameters (air temperature and solar radiation) were used to predict the concentration of tropospheric ozone using the Design-Ease software. These data were collected on hourly basis over a 12-month period. Sampling of the data was conducted automatically. The effect of the NMHC, NO, NO2,CO, temperature and solar radiation variables in predicting ozone concentrations was examined under two scenarios: (i) when NO is included with the absence of NO2; and (ii) when NO2 is addressed with the absence of NO. The results of these two scenarios were validated against ozone actual data. The predicted concentration of ozone in the second scenario (i.e., when NO2 is addressed) was in better agreement with the real observations. In addition, the paper indicated that statistical models of hourly surface ozone concentrations require interactions and non-linear relationships between predictor variables in order to accurately capture the ozone behavior. [ABSTRACT FROM AUTHOR]

There is concern about the hazard of acute residential CO exposures from portable gasoline-powered generators, which can result in death or serious adverse health effects in exposed individuals. To address this hazard, the U.S. Consumer Product Safety Commission has developed low CO emission prototype generators by adapting off-the-shelf emission control technologies onto commercially available generators. A series of tests was conducted to characterize the indoor CO concentrations resulting from portable generators operating in the attached garage of a research house under seven different test house/garage configurations. The tested generators include both unmodified and modified low CO emission prototypes. It was found that CO concentrations varied widely, with peak house CO concentrations ranging from under 10 ppm to over 10,000 ppm. The highest concentrations in the house resulted from operation of the unmodified generator in the garage with the garage bay door closed and the house access door open. The lowest concentrations resulted from operation of a modified low CO emission prototype in the garage with the garage bay door open and the house access door closed. These tests documented reductions of up to 98% in CO concentrations due to emissions from two low CO emission portable generators compared to a stock generator. Implications: Improper portable generator use has caused 800 U.S. deaths in the past 14 years. Generators operated in attached garages can cause CO to quickly reach deadly levels. Two low-emission prototypes generators were tested and had CO emissions reduced by up to 98%. Low-emission generators can reduce the risk of consumer poisonings and deaths. [ABSTRACT FROM AUTHOR]

Exposure to traffic emission is harmful to human health. Emission inventories are essential to public health policies aiming at protecting human health, especially in areas with incomplete or nonexistent air pollution monitoring networks. In Brazil, for example, only 1.7% of municipal districts have a monitoring network, and only a few studies have reported data on vehicle emission inventories. No studies have presented emission inventories by municipality. In this study, we predicted vehicular emissions for 5570 municipal districts in Brazil during the period 2001–2012. We used a top-down method to estimate emissions. Carbon dioxide (CO2) is the pollutant with the highest emissions, with approximately 190 million tons per year during the period 2001–2012). For the other traffic-related pollutants, we predicted annual emissions of 1.5 million tons for carbon monoxide (CO), 1.2 million tons of nitrogen oxides (NOx), 209,000 tons of nonmethane hydrocarbons (NMHC), 58,000 tons of particulate matter (PM), and 42,000 tons for methane (CH4). From 2001 to 2012, CO, NMHC, and PM emissions decreased by 41, 33, and 47%, respectively, whereas those CH4, NOx, and CO2increased by 2, 4, and 84%, respectively. We estimated uncertainties in our study and found that NOxwas the pollutant with the lowest percentage difference, 8%, and NMHC with the highest one, 30%. For CO, CH4, CO2, and PM, the values were 22, 14, 21, and 20%, respectively. Finally, we found that during 2001 and 2012 emissions increased in the Northwest and Northeast. In contrast, pollutant emissions, except for CO2, decreased in the Southeast, South, and part of Midwest. Our predictions can be critical to efforts developing cost-effective public policies tailored to individual municipal districts in Brazil. Implications: Emission inventories may be an alternative approach to provide data for air quality forecasting in areas where air quality data are not available. This approach can be an effective tool in developing spatially resolved emission inventories. [ABSTRACT FROM AUTHOR]

Canadian wildfire smoke impacted air quality across the northern Mid-Atlantic (MA) of the United States during June 9–12, 2015. A multiday exceedance of the new 2015 70-ppb National Ambient Air Quality Standard (NAAQS) for ozone (O3) followed, resulting in Maryland being incompliant with the Environmental Protection Agency’s (EPA) revised 2015 O3NAAQS. Surface in situ, balloon-borne, and remote sensing observations monitored the impact of the wildfire smoke at Maryland air quality monitoring sites. At peak smoke concentrations in Maryland, wildfire-attributable volatile organic compounds (VOCs) more than doubled, while non-NOx oxides of nitrogen (NOz) tripled, suggesting long range transport of NOx within the smoke plume. Peak daily average PM2.5was 32.5 µg m−3with large fractions coming from black carbon (BC) and organic carbon (OC), with a synonymous increase in carbon monoxide (CO) concentrations. Measurements indicate that smoke tracers at the surface were spatially and temporally correlated with maximum 8-hr O3concentrations in the MA, all which peaked on June 11. Despite initial smoke arrival late on June 9, 2015, O3production was inhibited due to ultraviolet (UV) light attenuation, lower temperatures, and nonoptimal surface layer composition. Comparison of Community Multiscale Air Quality (CMAQ) model surface O3forecasts to observations suggests 14 ppb additional O3due to smoke influences in northern Maryland. Despite polluted conditions, observations of a nocturnal low-level jet (NLLJ) and Chesapeake Bay Breeze (BB) were associated with decreases in O3in this case. While infrequent in the MA, wildfire smoke may be an increasing fractional contribution to high-O3days, particularly in light of increased wildfire frequency in a changing climate, lower regional emissions, and tighter air quality standards. Implications: The presented event demonstrates how a single wildfire event associated with an ozone exceedance of the NAAQS can prevent the Baltimore region from complying with lower ozone standards. This relatively new problem in Maryland is due to regional reductions in NOx emissions that led to record low numbers of ozone NAAQS violations in the last 3 years. This case demonstrates the need for adequate means to quantify and justify ozone impacts from wildfires, which can only be done through the use of observationally based models. The data presented may also improve future air quality forecast models. [ABSTRACT FROM PUBLISHER]

The operating characteristics of a single-cylinder four-stroke variable compression ratio engine fueled with esterified tamanu oil were investigated. The suitability of esterified Tamanu oil produced from pinnai oil by transesterification process has been studied in variable compression ratio engine. Experiment has been conducted at various loads like 0 kg, 3 kg, 6 kg, 9 kg, and 12 kg with engine speed of 1500 rpm and at compression ratio varies from 14:1 to 18:1. The impact of compression ratio on fuel consumption, combustion parameters, and exhaust gas emissions is investigated. In order to vary the compression ratio, the clearance volume is changed geometrically by tilting cylinder block arrangement. The performance characteristics like specific fuel consumption, brake power, mean effective pressure, brake thermal efficiencies, and exhaust gas temperature are analyzed for Tamanu oil in the variable compression ratio engine. The emission characteristics like hydrocarbon, nitrogen oxides, carbon monoxide, and carbon dioxide emissions are also measured for Tamanu oil in the same engine. The effect of intake valve closing event-timing modulation on effective compression ratio was also investigated. The motivation behind this analysis was to fix the effective compression ratio for biodiesel. [ABSTRACT FROM PUBLISHER]

This study examines the impacts of air pollution on low birth weight by considering overtime variation in Korea in early 2000, when some parts of Korea experienced huge drop in air pollution due to regulation. The mother's exposure to ozone level above 0.12 ppm per hour during the first trimester increased the probability of low birth weight by 0.4 percentage point (0.08% of the sample mean). Exposure to carbon monoxide or sulphur dioxide (SO2) during the third trimester also led to a significant but modest increase in the probability of low birth weight. [ABSTRACT FROM PUBLISHER]

Carr D. and Yan W. Federal environmental policy and local industrial diversification: the case of the Clean Air Act, Regional Studies. Air-quality regulations under the Clean Air Act alter local industrial diversification by reducing concentration in polluting sectors of the economy for non-attainment areas. Using comprehensive county-level data covering the entire United States over a period of twenty-six years, this study finds an important connection between air-quality regulations and local industrial diversification in both non-attainment areas and jurisdictions that have gained attainment status. Non-attainment status for ozone, carbon monoxide (CO) or sulphur dioxide (SO2) brings about significant decreases in local industrial specialization. Furthermore, these effects persist after attainment status has been gained for ozone, carbon monoxide, or sulphur dioxide. Carr D. et Yan W. La politique fédérale pour l'environnement et la diversification industrielle locale: étude de cas de la loi antipollution, Regional Studies. Les dispositions réglementaires pour la qualité de l'air, conformément à la loi antipollution, modifient la diversification industrielle locale en réduisant la concentration des secteurs polluants de l'économie dans les zones qui ne réalisent pas les cibles d'acquisition. A partir des données globales recueillies au niveau du comté et qui traitent des Etats-Unis entiers sur une période de vingt-six années, il s'avère un lien important entre les dispositions réglementaires pour la qualité de l'air et la diversification industrielle locale à la fois dans les zones qui n'ont pas réalisé les cibles d'acquisition et dans les circonscriptions qui les ont réalisées. Là où l'on n'a pas réalisé les cibles d'acquisition pour ce qui est de l'ozone, du monoxide de carbone (CO), de l'anhydride sulfureux (SO2), cela entraîne d'importantes baisses de la spécialisation industrielle locale. Qui plus est, ces effets persistent une fois réalisé les cibles d'acquisition pour ce qui concerne l'ozone, le monoxide de carbone, ou l'anhydride sulfureux. Diversification industrielle?Géographie économique?Loi antipollution?Politique pour l'environnement?Spécialisation?Economie urbaine Carr D. und Yan W. Umweltpolitik und lokale industrielle Diversifizierung auf Bundesebene in den USA: der Fall des Clean Air Act, Regional Studies. Aufgrund der Luftreinhaltungsvorschriften des Clean Air Act ändert sich für Gebiete, die die Vorschriften nicht einhalten, die lokale industrielle Diversifizierung durch eine Verringerung der Konzentration in umweltbelastenden Wirtschaftssektoren. Mit Hilfe von umfangreichen Daten auf Bezirksebene für die gesamten USA während eines Zeitraums von 26 Jahren wird in dieser Studie ein wichtiger Zusammenhang zwischen den Luftreinhaltungsvorschriften und der lokalen industriellen Diversifizierung festgestellt, was sowohl für Gebiete gilt, die die Vorschriften nicht einhalten, als auch für Gebiete mit Einhaltungsstatus. Ein Nichteinhaltungsstatus für Ozon, Kohlenmonoxid (CO) oder Schwefeldioxid (SO2) führt zu einer signifikanten Abnahme der lokalen industriellen Spezialisierung. Darüber hinaus halten diese Effekte auch an, wenn für Ozon, Kohlenmonoxid oder Schwefeldioxid ein Einhaltungsstatus erzielt wurde. Industrielle Diversifizierung?Wirtschaftsgeografie?Clean Air Act?Umweltpolitik?Spezialisierung?Urbane Ökonomie Carr D. y Yan W. Políticas medioambientales federales y la diversificación industrial local: el caso de la Ley de Aire Limpio, Regional Studies. Las normas de calidad del aire según la Ley de Aire Limpio (Clean Air Act) alteran la diversificación industrial a nivel local reduciendo la concentración en los sectores contaminantes de la economía para áreas de no cumplimiento. Con ayuda de exhaustivos datos de condados que abarcan todo Estados Unidos durante un periodo de veintiséis años, en este estudio observamos una conexión importante entre las regulaciones de la calidad del aire y la diversificación industrial a nivel local en áreas de no cumplimiento y en jurisdicciones que han adquirido un estatus de cumplimiento. El estatus de no cumplimiento para el ozono, el monóxido de carbono (CO) o el dióxido de azufre (SO2) lleva a reducciones considerables en la especialización industrial local. Asimismo estos efectos persisten tras obtener un estatus de cumplimiento para el ozono, el monóxido de carbono o el dióxido de azufre. Diversificación industrial?Geografía económica?Ley de Aire Limpio?Política medioambiental?Especialización?Economía urbana [ABSTRACT FROM PUBLISHER]

Occupational exposure to carbon monoxide continues to cause a number of injuries and deaths. This study reviewed the State of Washington OSHA inspection records for occupational safety or health violations related to carbon monoxide for the time period 1994-1999 to assess the agency's efforts and further identify and characterize causative factors. Inspection data were also compared with carbon monoxide claims data from a companion study to determine if the agency was visiting the most at risk work operations. Inspections were identified by searching computerized violation texts for "carbon monoxide" or "CO." The study found 142 inspections with one or more carbon monoxide violations. Inspections were spread over 84 different 4-digit Standard Industrial Classification codes. Most inspections were initiated as a result of a complaint or other informant. Inspections were predominantly in construction and manufacturing, whereas carbon monoxide claims were mores evenly distributed between the major industries. Inspections also may have failed to find violations for some types of equipment responsible for carbon monoxide claims. Forklifts were the source of carbon monoxide most often associated with a violation, followed by compressors for respirators, auto/truck/bus, and temporary heating devices. Inspections in response to poisonings found common factors associated with lack of recognition and failure to use or maintain equipment and ventilation. Some work sites with one or more poisonings were not being inspected. Only 10 of the 51 incidents with industrial insurance claim reports of carboxyhemoglobin at or above 20 percent were inspected. Further, it was found more preventive efforts should be targeted at cold storage operations and certain warehouse and construction activities. It is proposed that more specific standards, both consensus and regulatory, would provide additional risk reduction. Reliance upon safe work practices as a primary method of control in the use of fuel-powered equipment in cold storage or other enclosed and unventilated environments needs to be prohibited. The study further demonstrates how inspection and industrial insurance records can assist with preventive efforts and better focus an agency's efforts. [ABSTRACT FROM AUTHOR]

Presents an approach to carbon monoxide modeling for urban air quality management. Concentration of carbon monoxide over a specified time period; Changes in the pollutant emission characteristics; Prediction of the averaged carbon monoxide concentrations for both temporal and spatial emission alterations.

Presents test questions on industrial hygiene for safety professionals who wish to continue their certification. Estimation and controlling workplace risk; Spectrophotometric method for the determination of organic soluble matter in bitumen fumes; Occupational carbon monoxide violations in Washington state.