Air Pollution Effects of Incinerator Firing Practices and Combustion Air Distribution

A survey of academic programs in air pollution control was made. Results from the 127 schools reporting are tabulated by state. Faculty involved in air pollution instruction are identified. Some conclusions and recommendations are presented.     

室内空气污染现状及其防治对策

介绍了我国室内空气污染现状，明确了主要污染物及其危害，提出了相关的防治对策。     

室内空气污染的生物监测与生物防治

介绍了室内空气污染的来源及其危害,采用常见花木来监测室内的空气污染,并可用常见盆栽植物来防治室内的空气污染.     

室内空气污染分析及防治措施

简述了室内空气污染的种类和特点，多角度论述了室内空气污染的防治措施。     

The Effects of Air Pollution on Exposed Cotton Fabrics

This report covers the results of one-year exposure studies of cotton fabrics exposed at different environmental sites in the metropolitan St. Louis, Mo., and Chicago, III. areas. The 12 sites range from heavy industrial to essentially rural. The data presented definitely establish a relationship between air pollution and accelerated degradation of cotton fabrics. The data include strength retention of several cotton fabrics and air pollution data, as determined by periodic measurement of dustfall, suspended particulate matter, sulfation, and sulfur dioxide.     

Dissociation of Sulfur Hexafluoride Tracer Gas in the Presence of an Indoor Combustion Source

ABSTRACT

As an odorless, nontoxic, and inert compound, sulfur hexafluoride (SF₆) is one of the most widely used tracer gases in indoor air quality studies in both controlled and uncontrolled environments. This compound may be subject to reactions with water vapor under elevated temperature to form acidic inorganic compounds such as HF and H₂SO₄. Thus, in the presence of unvented combustion sources such as kerosene heaters, natural gas heaters, gas log fireplaces, candles, and lamps, the SF₆ dissociation may interfere with measurements of the emissions from these sources. Tests were conducted in a research house with a vent-free natural gas heater to investigate these potential interferences. It was observed that the heater operation caused about a 5% reduction of SF₆ concentration, which can be an error source for the ventilation rate measurement and consequently the estimated pollutant emission rates. Further analysis indicates that this error can be much greater than the observed 5% under certain test conditions because it is a function of the ventilation flow rate. Reducing the tracer gas concentration has no effect on this error. A simple theoretical model is proposed to estimate the magnitude of this error.

The second type of interference comes from the primary and secondary products of the SF₆ dissociation, mainly H₂SO₄, SO₂, HF, and fine particulate matter (PM). In the presence of ~5 ppm SF₆, the total airborne concentrations of these species increased by a factor of 4-10. The tests were performed at relatively high SF₆ concentrations, which is necessary to determine the interferences quantitatively. The second type of interference can be significantly reduced if the SF₆ concentration is kept at a low ppb level.     

The Effects of Air Pollution On the Fading of Dyed Fabrics

This report details results for the first six months of a two-year study begun in February 1965 by The American Association of Textile Chemists and Colorists and the Public Health Service to evaluate the effects of air pollution upon dyed fabrics. Groups of 69 dye-fabric combinations representing widely used dyes were exposed in light-free cabinets to ambient environments at urban and rural sites in Chicago, Washington, D. C, Tacoma, and Los Angeles, and at urban sites in Cincinnati, Phoenix, and Sarasota. Preliminary results of consecutive three-month seasonal exposures and controlled-environment exposures to irradiated and nonirradiated automobile exhaust for short durations show extreme fading of one-fourth of the dyed-fabrics, a higher degree of fading of susceptible fabrics at urban sites compared with that at rural sites, and a marked effect of photochemical by-products of automobile exhaust upon dyed fabrics.     

Measuring the Organic Carbon Content of Source Emissions for Air Pollution Control

Measuring emissions of organic materials from such sources as paint bake ovens, degreas-ing operations, and printing processes is a necessy part of a control program for solvents. Over the intervening years since 1966 when Los Angeles first enacted its solvent Rule 66, a considerable number of tests have been performed and the present test method has gone through a period of experience and improvement. A sample is collected from a stack or vent in a freeze-out trap cooled with dry ice followed by an evacuated 8-liter tank. Analysis is done by a system of gas chromatography and catalytic combustion to yield the total organic carbon content. Representative industrial emission analysis results, which demonstrate the practical applicability of the system, are shown.     

Numerical Evaluation of the Effect of Traffic Pollution on Indoor Air Quality of a Naturally Ventilated Building

Abstract

A computational fluid dynamics technique was used to evaluate the effect of traffic pollution on indoor air quality of a naturally ventilated building for various ventilation control strategies. The transport of street-level nonreactive pollutants emitted from motor vehicles through the indoor environment was simulated using the large eddy simulation (LES) of the turbulent flows and the pollutant transport equations. The numerical model developed herein was verified by available wind-tunnel measurements. Good agreement with the measured velocity and concentration data was found. Twelve sets of numerical scenario simulations for various roof- and side-vent openness and outdoor wind speeds were carried out. The effects of the air change rate, the indoor airflow pattern, and the external pollutant dispersion on indoor air quality were investigated. The control strategies of ventilation rates and paths for reducing incoming vehicle pollutants and maintaining a desirable air change rate are proposed to reduce the impact of outdoor traffic pollution during traffic rush hours. It was concluded that the windward side vent is a significant factor contributing to air change rate and indoor air quality. Air intakes on the leeward side of the building can effectively reduce the peak and average indoor concentration of traffic pollutants, but the corresponding air change rate is relatively low. Using the leeward cross-flow ventilation with the windward roof vent can effectively lower incoming vehicle pollutants and maintain a desirable air change rate during traffic rush hours.     

Air Pollution Emissions from the Incineration of Hospital Waste

Since 1981, hospitals in Illinois have been prohibited from depositing hazardous infectious waste in landfills without first rendering the waste innocuous. The Illinois Pollution Control Board has adopted regulations indicating that incineration is an acceptable method for disposal of this waste. Emissions from incineration of the plastic-rich hospital waste are not well documented. Stack emissions of particles, hydrochloric acid, carbon monoxide, ethane, ethylene, propane and propylene were measured from a hospital incinerator where all of the hospital's waste (including hazardous infectious waste) was burned. Emission factors developed for each emission component were: particles 1.0–1.6 g/kg waste; hydrochloric acid 3.3–5.3 g/kg; carbon monoxide 1.4–1.8g/kg; ethane <0.002g/kg; ethylene <0.010g/kg; propane <0.012 g/kg; and propylene <0.011 g/kg     

Industrial Responsibilities in and Advantages from the Control of Air Pollution

The requirements for public participation in air pollution control programs have been significantly increased by the 1977 Clean Air Act Amendments. This paper is directed to state and local agency officials, to assist them in carrying out these responsibilities under the Act. The changes in the Act and the guidelines that have been issued pursuant to these new provisions are summarized. The elements of an effective public participation program are described. The current status of public participation in state implementation plan revision programs is reported.     

The South Karelia Air Pollution Study: Relationship of Outdoor and Indoor Concentrations of Malodorous Sulfur Compounds Released by Pulp Mills

We studied the indoor penetration of ambient air malodorous sulfur compounds released by pulp mills. The indoor and outdoor concentrations were simultaneously measured with automatic SO₂ analyzers. The filtering effect of three different materials connected to a gaseous filter unit was tested during six study periods. The tested materials were Sorbixofil® based on gypsum impregnated by KMnO₄ Purafil® based on Al₂O₃, both absorbing sulfur compounds by oxidation, and carbonized tissue. The periods lasted from 14 to 88 days. The results indicated that malodorous sulfur air pollutants penetrated indoors effectively, but after some delay because the dilution was slow. In a comparison of different filter materials, Purafil® was the most effective, producing low indoor concentrations. The study concludes that people living near pulp mills are exposed to substantial amounts of malodorous air pollutants, both indoors and outdoors. This exposure can be reduced by using gaseous sulfur sensitive filter materials connected to a controlled ventilation system.     

Problems of Relating Atmospheric Analyses to Effects of Air Pollution on Agriculture

Relating of air pollution concentrations to effects on agriculture is hampered by deficiencies in present methods of atmospheric analysis and by inadequate knowledge about how various factors modify the effects. Analytical methods frequently lack sufficient sensitivity or specificity to determine accurately the substances involved. Typical examples include the difficulty of distinguishing among fluoride compounds with loidely differing phytotoxic activity, the serious interference from concomitant air pollutants with the usual methods of determining ozone, and the common failure or inability to detect short interval concentration extremes which may cause acute injury. The interrelationship of pollutant concentration and length of exposure in determining plant injury is poorly understood, as are the modifying effects of environmental conditions and age of tissue. The identity of some of the phytotoxic components of the urban photochemical pollution complex is still uncertain, making it difficult to select appropriate analytical methods. Caution should be exercised in using atmospheric analysis data to predict effects of air pollution on agriculture until these deficiencies in analytical methods and understanding of the problem are overcome.