Volatile Organic Compounds control measures

Hundreds of chemical species are present in urban atmospheres. The gaseous air pollutants most commonly monitored are CO, O3, NO2, SO2, and nonmethane volatile organic compounds (NMVOCs), Measurement of specific hydrocarbon compounds is becoming routine in the United States for two reasons (1) their potential role as air toxics and (2) the need for detailed hydrocarbon data for control of urban ozone concentrations. Hydrochloric acid (HCl), ammonia (NH3), and hydrogen fluoride (HF) are occasionally measured. Calibration standards and procedures are available for all of these analytic techniques, ensuring the quality of the analytical results... 

Carlson, F.E., Phillips, E.K., Tenhaeff, S.C. and Detlefsen, W.D., Measuring and Controlling Volatile Organic Compound and Paniculate Emissions from Wood Processing Operations and Wood-Based Products. Forest Products Society, Madison WI, 1995, pp. 52-61. 

Harkov R, Kebbekus B, Bozzelli JW, et al. 1983. Measurement of selected volatile organic compounds at three locations in New Jersey during the summer season. J Air Pollut Control Assoc 33 1177-1183. 

The Japanese Air Pollution Control Law dates back to 1968 and was designed to promote comprehensive air pollution control measures. Subsequent revisions have included extensions of regulatory objects, nationwide regulation and enforced standards, e.g. those for specific dust (asbestos) in 1989, vehicle fuel in 1995, harmful air pollutants in 1996 and volatile organic compounds (VOC) in 2004. Article 1 of the recent Japanese Air Pollution Control Law [16] states ... 

Cohen, M., Ryan, P., Yanagisawa, Y., Spengler, J., Ozkaynak, H. and Epstein, P. (1989) Indoor/outdoor measurements of volatile organic compounds in the Kanawha Valley of West Virginia. Journal of the Air Pollution Control Association, 39, 1086-93. 

Volatile organic compounds (VOCs) and carbon dioxide (C02) are two major indicators of indoor air pollution in air-conditioned office buildings. Indoor air quality assessments would include VOCs and C02 measurements and attempt to identify their sources so that strategies for effective control may be implemented. Options for control may be source control and ventilation. Source control is the more effective while ventilation is potentially expensive, given the unpredictable (and usually rising) cost of energy. 

M.D. Koontz and M.L. Hoang, Volatile Organic Compound Emissions from Particleboard and Medium Density Fiberboard, Proceedings of Measuring and Controlling VOCs, No.7301, Forest Products Society, WI, USA, 1995, p.76-87. 

Biofiltration works to degrade a diversity of airborne contaminants, including industrial chemicals like styrene (Arnold et al. 1997), pentane and isobutane mixtures (Barton et al. 1997), toluene (Matteau and Ramsay 1997), chlorinated benzenes (Oh and Bartha 1994), dimethylsulfide (Pol et al. 1994), ethylene (Elsgaard 1998), and other volatile organic compounds (VOCs Leson and Winer 1991). Maintenance of good degrada-tive activity of biofilter microbial communities sometimes requires the addition of nutrients to the bioliltration matrix, since materials like peat or wood chips are generally nutrient poor. Adjustments and careful control of environmental variables such as temperature, pH, and availability of moisture (humidity) also are often required (Arnold et al. 1997 Matteau and Ramsay 1997). Removal rates for contaminants by biofilters can be impressive. For example, removal of vapors of chlorinated compounds (chlorinated benzenes, in one instance) was measured at 300 g of solvent vapor h m of filter volume (Oh and Bartha 1994). 

Urban Polluted Air Urban polluted air contains a few hundred species of hydrocarbons and oxygen containing volatile organic compounds (OVOCs) (Lewis et al. 2000), and the observation of OH and HO2 concentrations there validates the reaction model with the whole set of these VOCs. Comparisons between the model calculation and observation of OH and HO2 concentrations in urban air are also interesting from the point of checking the dependence of O3 formation rate on NOx and VOC in the polluted atmosphere, and are important as validation of a reaction model for the discussirai of the oxidant control strategy as described in the previous section. From these viewpoints, many measurements of and the comparison with model calculations have been made in urban air, and the values of (3-20) X 10 molecules cm for OH, and (1-12) x 10 molecules cm (4-50 pptv) for HO2 concentration, which are similar or higher than in the marine boundary layer, have been reported (Stone et al. 2012). 

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