Showing papers on "Air quality index published in 1992"

Comparison of Emission Inventory and Ambient Concentration Ratios of CO, NMOG, and NOx in California's South Coast Air Basin

Abstract: In the present study, we performed a "top-down" validation of the reactive organic gas and carbon monoxide emission inventories for California's South Coast Air Basin by comparing speciation profiles for nonmethane organic gases (NMOG) and ratios of CO/NOx and NMOG/NOx derived from early-morning (0700 to 0800) ambient measurements taken during the 1987 Southern California Air Quality Study with the corresponding ratios and speciation profiles derived from day-specific, hourly, gridded emission inventories. We considered twenty separate comparisons for each ratio, each representing a different combination of season, emission category, and spatial and temporal averaging of emissions. We determined that the most appropriate comparison in summer was ambient pollutant ratios with ratios derived from morning on-road motor vehicle emission inventories, and in the fall, ambient ratios with ratios derived from overnight on-road motor vehicle emission inventories with some contribution from overnight stationary-sou...

National air quality and emissions trends report, 1991. Annual report

Abstract: The report presents national and regional trends in air quality from 1982 through 1991 for particulate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide, ozone and lead. Air quality trends are also presented for 15 metropolitan areas. Both national and regional trends in each of these pollutants are examined. National air quality trends are also presented for both the National Air Monitoring Sites (NAMS) and other site categories. In addition to ambient air quality, trends are also presented for annual nationwide emissions. These emissions are estimated using the best available engineering calculations; the ambient levels presented are averages of direct measurements. International comparisons of air quality and emissions are also contained in this report. This report also includes a section, Air Quality Levels in Metropolitan Statistical Areas (MSAs). Its purpose is to provide interested members of the air pollution control community, the private sector and the general public with greatly simplified air pollution information. Air quality statistics are presented for each of the pollutants for all MSAs with data in 1991.

The environmental consequences of urban growth: cross-national perspectives on economic development, air pollution, and city size

Abstract: This study presents a quantitative assessment of the environmental consequences of urbanization in general and city bigness in particular in the context of the process of economic development. We focus attention on the relationship between ambient air quality and city size, and how it might differ between urban areas of developed and developing countries. First, the air pollution-city size relationship is characterized theoretically and explored empirically using ambient air quality data for various urban zones across an international sample of cities. While we find statistically significant relationships between pollution and city size, interesting developed-developing country differences emerge. Next, the relationship is re-estimated using contextual development covariates. Results show that the positive association between poor air quality and city size is not inevitable and tends to diminish with economic growth and the capacity for undertaking pollution abatement measures. It follows that restricting...

Regulating Indoor Air

Abstract: The possibilities to reduce indoor air pollution comprise source control, dilution and the setting of limit values for indoor air pollutants. While emission standards, voluntary agreements, and even bans are elements of the first option, the dilution approach includes ventilation standards and air cleaning devices. In contrast to the situation for outdoor air and the air at work places, setting air quality standards does not seem to be the appropriate way to reduce indoor air pollution. Rather, the use of guideline values for indoor air pollutants is recommended. Guideline values may be set two at a time, one defining a level of hazard for immediate action, the other a target concentration for the future. The example of tetrachloroethene is chosen to illustrate the applicability of the concept in practice.

Air quality conditioning system

Abstract: An air quality conditioning system for adjusting an environmental air quality in an accommodation space comprises; a detection device for detecting the air quality; another detection device for detecting the temperature and humidity; a signal processor for identifying the causes for the change in the air quality of the accommodation space based on the outputs of said detection devices, and also determining the degree of the change based on the discomfort degree data for the air quality, with another function of correcting the outputs of said detection means for the temperature and humidity.

Assessment of the potential for photochemical air pollution in Athens : a comparison of emissions and air-pollutant levels in Athens with those in Los Angeles

Abstract: The average areal density of pollutant emissions in Athens is estimated to be two to six times greater than in the Los Angeles basin. Concentration levels of the primary air pollutants, CO and SO2, are several times larger in Athens than in Los Angeles. Concentrations of the photochemical pollutants, NO2 and O3, however, are greater at Los Angeles stations inland 20 or more kilometers from the coast. The relatively lower levels of photochemical pollution in Athens are partially explained by differences in the summer atmospheric-circulation systems and the scale of the basins. Also, the concentration of NO in central Athens is so great as to inhibit the formation of O3.

Advanced emission speciation methodologies for the auto/oil air quality improvement research program. I: Hydrocarbons and ethers

Abstract: An analytical method for the determination of hydrocarbon and ether emissions from gasoline-, methanol-, and flexible-fueled vehicles is described. This method was used in Phase I of the Auto/Oil Air Quality Improvement Research Program to provide emissions data for various vehicles using individual reformulated gasolines and alternate fuels. These data would then be used for air modeling studies. Emission samples for tailpipe, evaporative, and running loss were collected in Tedlar bags. Gas chromatographic analysis of the emissions samples included 140 components (hydrocarbons, ethers, alcohols and aldehydes) between C1 and C12 in a single analysis of 54-minutes duration. Standardization, quality control procedures, and inter-laboratory comparisons developed and completed as part of this program are also described. (Copyright (c) 1992 Society of Automotive Engineers, Inc.).

Chemical, microbiological, health and comfort aspects of indoor air quality : state of the art in SBS

Abstract: A. Introduction.- The Sick Building Syndrome - Overview and Frontiers.- B. Chemical and Biological Aspects.- The dynamics of the indoor environment and some strategical aspects of indoor measurements.- Organic indoor pollutants - sources, species, and concentrations.- Sampling and analysis of organic indoor air pollutants.- Characterization of organic emissions from indoor sources.- Sensory characterization of air quality and pollution sources.- Indoor microbiological pollutants - sources, species, characterisation and evaluation.- C. Effects of Indoor Air Pollution on Humans.- Irritation of the upper airways. Mechanisms and structure-activity relationships.- Assessment methods and causes of eye irritation in humans in indoor environment.- Indoor environment and the skin.- Sensory effects for indoor air quality control.- Indoor air pollution: immunological interactions.- Indoor pollution and allergic sensitization.- Chemical hyper-responsiveness.- Some studies of human reactions from the emissions of building materials and office machines.- Human reactions to controlled exposures to VOC's and the "TOTAL-VOC" concept.- D. 'Sick' Building Epidemiology.- Questionnaires in exposure and effect assessment in the field.- The effects of microbiological pollution in buildings - results of building investigations.- Building epidemiology - approaches and results (European experience).- Building epidemiology and investigations - approaches and results (U.S. experience).- E. Mitigation and Control.- Regulating indoor air.- Controlling sources of indoor air pollution.- Construction and health - criteria, standards and techniques against indoor pollution.- Healthy buildings - where do we stand, where should we go?.

Control of Airborne Particle Concentration and Draught Risk in an Operating Room

Abstract: The influence of location of airborne particle source, ventilation rate, air inlet size, supply air velocity, air outlet location, and heat source on the distributions of airborne particle concentration and draught risk in an operating room is investigated. The investigation is carried out by using flow program with the k-e model of turbulence. Based on a standard case, five cases, each with one changed parameter, are computed, and the detailed field distributions of air velocity, temperature, airborne particle concentration, and draught risk are presented. The parametric study concludes that, for a better air quality and thermal comfort, it is desirable to use a higher inflow rate, a larger inlet area, and a uniform velocity profile of supply air. Outlet location and heat source have little influence on the distributions ofthe particle concentration in the room. It has also been found that the distributions of particle concentration in the recirculating zone are very sensitive to the location of the particle sources.

The UK environment

Abstract: Climate air quality and pollution the global atmosphere soil land use and land cover inland water resources and abstraction inland water quality and pollution the marine environment coast erosion, flooding and sea level change wildlife waste and recycling noise radioactivity environment and health pressures on the environment public attitudes expenditure on the environment.

An Improved Dispersion Model for Regulatory Use — The OML Model

Abstract: In 1990 a revised set of Air Quality Guidelines was issued by the Danish Environmental Protection Agency. In Denmark, environmental policy primarily aims at reducing emissions. However, all sources must also fulfil certain requirements assuring that their contribution to local pollution concentrations in the air does not exceed certain limits. Thus, the set of Air Quality Guidelines prescribes acceptable concentration levels for a large number of chemical species, as well as a procedure which should generally be adhered to by local environmental agencies when new emission sources are being planned. The procedure recommends use of the so-called OML model for atmospheric dispersion calculations. This model is available in different PC versions, one of which is designed specifically for use in combination with the Guidelines. Accordingly, the model is now being widely used in Denmark by nonexpert users in local environmental agencies, by consulting engineers and by large industries.

Statistical Analysis of Trends in Urban Ozone Air Quality

Abstract: The purpose of this paper is to demonstrate the use of some statistical methods for examining trends in ambient ozone air quality downwind of major urban areas. To this end, daily maximum 1-hr ozone concentrations measured over New Jersey, metropolitan New York City and Connecticut for the period 1980 to 1989 were assembled and analyzed. This paper discusses the application of the bootstrap method, extreme value statistics and a nonparametric test for evaluating trends in urban ozone air quality. The results indicate that although there is an improvement in ozone air quality downwind of New York City, there has been little change in ozone levels upwind of New York City during this ten-year period.

Summary of selected new information on effects of ozone on health and vegetation: Supplement to 1986 Air Quality Criteria for Ozone and Other Photochemical Oxidants

Abstract: Since completion of the 1986 Air Quality Criteria Document for Ozone, additional information has become available that warrants consideration by U.S. Environmental Protection Agency (U.S. EPA) in its review of the National Ambient Air Quality Standards (NAAQS) for ozone. The summary reviews and evaluates selected literature published from 1986 through early 1989 on the vegetation and health effects resulting from exposure to ozone. Emphasis has been placed on evaluation of key human health effects literature and other data most pertinent to determination by U.S. EPA of the appropriate level and form of the primary NAAQs and the appropriate form of the secondary NAAQs.

Ozone Control Strategies Based on the Ratio of Volatile Organic Compounds to Nitrogen Oxides

Abstract: The 1990 Clean Air Act Amendments require states with O3 nonattainment areas to adopt regulations to enforce reasonable available control technologies (RACT) for NOX stationary sources by November 1992. However, if the states can demonstrate that such measures will have an adverse effect on air quality, NOX requirements may be waived. To assist the states in making this decision, the U.S. EPA is attempting to develop guidelines for the states to use in deciding whether NOX reductions will have a positive or negative impact on O3 air quality. Although NOX is a precursor of O3, at low VOC/NOX ratios, the reduction of NOX can result in increased peak O3. EPA is examining existing information on VOC/NOX ratios to develop “rules of thumb” to guide the states in their decision-making process. An examination of 6 a.m. to 9 a.m. VOC/NOX ratios at a number of sites in the eastern U.S. indicates that the ratio is highly variable from day-to-day and there is no apparent relationship between ratios measured at differ...

Commissioning to avoid indoor air quality problems

Abstract: This paper reports on indoor air quality (IAQ) which has become a pervasive problem plaguing the building industry worldwide. Poor IAQ in commercial and office buildings is primarily related to new building technology, new materials and equipment and energy management operating systems. Occupants of buildings with air quality problems suffer from a common series of symptoms. As early as 1982, ASHRAE, realizing the significance of the problem, produced an IAQ position statement that identified strategies for solving IAQ problems. Many of those strategies have now been implemented, including Standard 62-1989, Ventilation for Acceptable Air Quality; Standard 90.1, Energy Efficient Design of New Buildings Except Low-Rise Residential Buildings; the 100 series of energy standards; and Guideline 1, Guideline for Commissioning of HVAC Systems.

Air exchange effectiveness in office buildings: Measurement techniques and results

Abstract: We define two air exchange effectiveness parameters which indicate the extent of short circuiting, mixing, or displacement air flow in an entire building, the air diffusion effectiveness which indicates the air flow pattern locally, and the normalized local age of air. After describing two tracer gas procedures for measuring these parameters, we discuss assumptions inherent in the data analysis that are often violated in large office buildings. To obtain valuable data, careful selection of buildings for measurements and assessments to determine if operating conditions are reasonably consistent with the assumptions are necessary. Multiple factors, in addition to the air flow pattern in the occupied space, can affect measurement results, consequently, the interpretation of measurements is not straightforward. We summarize the results of measurements in several office buildings and in a research laboratory. Almost all measurements indicate that the extent of both short circuiting and displacement flow is small. A moderate amount of short circuiting is evident from a few measurements in rooms with heated supply air. Ages of air and their reciprocals (local ventilation rates) often vary substantially between rooms, probably because of room-to-room variation in the rate of air supply. For future research, we suggest assessments of measurement accuracy,more » development of measurement approaches that may be practically applied for a broader range of buildings, and a greater focus on pollutant removal efficiencies.« less

Air Quality and Deposition

Abstract: The pollution climate of an area is influenced by meteorology and emissions of air pollutants at local and regional scales. The physical and chemical state of the atmosphere determines pollutant transport, dilution, chemical transformation, and ultimately deposition. In many cases, meteorology is more important than atmospheric chemistry in controlling the location and the form in which the pollutants are deposited (Cape and Unsworth 1987). Estimating pollutant concentrations and loadings to forests in the West requires a detailed analysis of emissions, pollutant transport, dilution, chemical transformations, and deposition processes, together with estimates of the relative contribution by each depositional process to total deposition.

Selected International Receptor-Based Air Quality Standards

Abstract: The ambient air quality standards (AAQS) of twenty-one nations for eight commonly regulated substances are presented. Many countries are adding a receptor-based component to their air quality management, which traditionally have been emission oriented. Automation of air quality monitoring stations has meant that local air quality evaluation can now be more easily achieved. However, a majority of countries have no active air quality standards (emission or receptor-based) or ambient air quality monitoring. One possible monitoring procedure is outlined and the variation in international standards is discussed.