Control of Contaminant Emissions From Fossil Fuel-Fired Boilers

The importance of fuels combustion was brought into sharp focus recently in a report on air pollution to the United States Senate in which it was stated, “These processes replace usable air with potentially harmful pollutants, and the capability of the atmosphere to disperse and dilute these pollutants—especially in urban areas where people, vehicles, and industries congregate in even greater numbers—is strictly limited.”¹ The overwhelming burden of emissions of sulfur compounds, as well as nitrogen compounds and particulate matter in the U. S. today, originates from the burning of coal and fuel oil in stationary combustion sources. Thus, combustion has a large influence on the quality of the atmosphere in most urban areas. The air pollution effects of these contaminants are many and varied and all are objectionable and undesirable. Without a doubt, the most serious air pollution problem in the nation today is that created by the combustion of fossil fuels.     

Analysis for Exhaust Gas Hydrocarbons—Nondispersive Infrared Versus Flame-lonizaticn

An investigation has been made of the suitability of a nondispersive infrared analyzer and two flame-ionization analyzers for measuring the total hydrocarbon concentrations of automobile exhaust gas. The investigation consisted of measuring relative responses of various hydrocarbons, checking for possible exhaust gas interferences and finally comparing exhaust hydrocarbon concentrations indicated by the flame-ionization analyzer to those indicated by the infrared analyzer. The infrared analyzer has high relative responses for parraffins and low responses for olefins, acetylenes, and aromatics. Also, the infrared indicated hydrocarbon concentrations must be corrected for exhaust water vapor interference. When the flameionization analyzers are operated at conditions that result in approximately uniform response to hydrocarbons and low oxygen interference, the exhaust hydrocarbon concentrations indicated by either flameionization analyzer are better approximations of the total hydrocarbon concentration than those indicated by the infrared analyzer.     

The Effects Of Ozone On Tobacco And Pinto Bean as Conditioned by Several Ecological Factors

The sensitivity of tobacco and/or pinto bean to ozone, as an air pollutant, is increased by growing plants in a shortened photoperiod under reduced light intensity and in a light potting mix. Sensitivity also is influenced by carbon dioxide concentration, time of day, and age of plant at time of exposure. Plants are more severely injured by a given dose under continuous exposure than when the exposure is split into two time periods. Tobacco shows cumulative development of injury when exposed to low concentrations intermittently over several days.     

APM-3 Recommended Standard Methods for Continuing Air Monitoring for Gaseous Contaminants

The purpose of Manual APM-3 is to provide a guide which will help increase the uniformity between various surveys, and thereby increase the useability of the data by others.     

Interactions of Environmental Factors on the Sensitivity of Plants to Air Pollution

Before potential damage to vegetation can be adequately forecast, even after an air pollution alert has been placed in effect, a clear understanding of the interactions of environment on plant sensitivity must be ascertained. This involves detailed study of single factors and then multiple factors using the phytotoxicants in question. Factors studied or suggested include light (quality, intensity, and duration), temperature, carbon dioxide concentration, humidity, wind, soil moisture, soil aeration, nutrient levels, and soil texture. This paper presents a review of the work relating plant injury to specific air pollutants as conditioned by several environmental conditions supported by research on the interactions of ozone with these environmental conditions.