Air quality

Impact on environmental air quality is regulated under the Clean Air Act (CAA). As described below, the Act sets national standards for emissions of certain pollutants and requires permits for some industrial operations. Greenhouse gases are not regulated as such therefore, they are not 

This section is adapted from Spellman, F.R., The Science of Air, 2nd ed., CRC Press, Boca Raton, FL, 2008. 

Conveniently grouped under the term air conditioning (or within the acronym HVAC), these filters are the basic means whereby improvement is achieved in the indoor air quality (lAQ) within which humans live or work. It is now believed that sick building syndrome, a condition that canses people to feel sick inside a certain building only to recover on leaving it, is an air-conditioning problem, likely to be cured by better filtration. 

Filters designed for the treatment of air fall broadly into three categories  

Electrostatic precipitators also come into this last category because of their capacity for ultra-fine dust filtration, although they can operate with much higher air velocities. 

A single-stage system using a low or medium efficiency filter has the lowest capital cost but, as stated, will not filter very fine contaminants. A multi-stage system will filter virtually all atmospheric pollution but at higher capital investment. The filter cost itself will be low, because the cheaper primary filters prolong the life of, and protect, the more expensive filters. 

Air filters and other types of air cleaning equipment can be grouped together as 

Sometimes people enter a room and notice at once that the air inside is stuffy , while most people inside the room have been getting tired, but were unaware of the poor air quality. This is because our biological air quality sensor, the nose, gets used to slow changes of surrounding smells. 

The second possibility to measure poor air quality is the detection of volatile organic compounds (VOC), but the number of different VOCs in room air is high, and often their impact on human health or comfort is not known. Additionally, the inconvenience caused by VOC s and smell is difficult to measure because it depends on human rating. 

A straightforward way to measure air quality is to measure the carbon dioxide concentration, which is a natural biological metabolite and increases especially in rooms filled with people. An increase in C02 is mainly responsible for sleepiness and could therefore serve as a direct measure of poor air quality. The base concentration of C02 in the ambient air is around 400 ppm. In non-ventilated rooms the C02-concentration can amount to more than 1000 ppm. Some carbon dioxide concentrations and limits and their impact on human comfort are listed in Tab. 5.4. 

COz sensors are suitable for living rooms, offices and bedrooms, whereas for bathrooms (main parameter humidity) and kitchens (main parameter smell ) other non-specific sensors may be used. Therefore combinations of different sensors like humidity sensors, smelF-sensors (unspecific VOC-sensors) and presence sensors could be the best solution. A simple movement detector with an additional manual override (ventilation on/off for a predetermined time) could be a low-cost alternative. 

There are several approaches to measuring electrolyte sensors [13], ultrasonic methods (acoustical), photo-acoustic cells [14] (Siemens C02 Controller), optical IR-detection and liquid-state electrochemical 

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COLORANTS FORFOOD,DRUGS,COSTffiTICS AND TffiDICALDEVICES] (Vol 6) NAAQS. See National Ambient Air Quality Standard. 

Potential health and safety problems of acryflc polymers occur in their manufacture (159). During manufacture, considerable care is exercised to reduce the potential for violent polymerizations and to reduce exposure to flammable and potentially toxic monomers and solvents. Recent environmental legislation governing air quality has resulted in completely closed ketde processes for most acryflc polymerizations. Acryflc solution polymers are treated as flammable mixtures. Dispersion polymers are nonflammable. 

Table 3. National Ambient Air Quality Standards for Criteria Pollutants ...

Mational Air Quality Emissions Trends Keport, 1989, Pub. No. EPA-450/4-91-003, U.S. Environmental Protection Agency, Research Triangle Park,... 

California Energy Commission, Methanol as a MotorEuel Review of the Issues Related to Air Quality, Demand, Supply, Cost, Consumer Acceptance and Health and Safety, Pub. P500-89-002, Sacramento, Calif., April 1989. 

United States Congress, Public Eaw 101-549, MnMct toMmend the Clean Air Met to Provide for Attainment and Maintenance of Health Protective National Ambient Air Quality Standards, andfor Other Purposes, Nov. 15,1990. 

ARCO Chemical Co., Testimony to the Colorado Air Quality Control Commission on Proposed Regulation Mo. 13 (Oyygenate Mandate Program), Denver, Colo., June 4,1987. 

Chemical Manufacturers Association, Improving Air Quality Guidance for Estimating Fugitive Emissions from Equipment, 2nd ed., CMA, Washington, D.C., 1989. Chemical Manufacturers Association, Responsible Care, Employee Health and Safety Code of Management Practices, CMA, Washington, D.C., 1992. 

For an excellent, comprehensive review of the chemistry, environmental, and anthropogenic release, environmental fate, and environmental and human health effects of lead, see Air Quality Criteria for Eead, Vol. I—IV, EPA-600/8-83/028a-dF, U.S. Environmental Protection Agency, Washington, D.C., June 1986, -Msd Air Quality Criteria for Eead Supplement to the 1986 Addendum, EPA-600/8-89/049F, U.S. Environmental Protection Agency, Washington, D.C., Aug. 1990. 

Air Quality Criteria forTead Supplement to the 1986 Addendum, U.S. EPA, Environmental Criteria and Assessment Office, Washington, D.C., 1990. Technical Support Document to Proposed Airborne Toxic Control Measure for Emissions of Toxic Metalsfrom Non-Ferrous Metal Melting, State of California Air Resources Board, Stationary Source Division, Sacramento, Calif., 1992. 

National Ambient Air Quality Standards. Under the Clean Air Act, six criterion pollutants, ie, pollutants of special concern, have been estabhshed by the EPA sulfur oxides (SO ), particulates, carbon monoxide (CO), nitrogen oxides (NO ), o2one (photochemical oxidants), and lead. National Ambient Air QuaUty Standards (NAAQS) were developed by EPA based on threshold levels of air pollution below which no adverse effects could be experienced on human health or the environment. 

Air Quality Criteria for Sulfur Oxides, National Air Pollution Control Administration, U.S. Dept, of Health, Education, and Welfare, Washington, D.C.,Jan. 1969, pp. 89-102. 

I. Air Quality Criteria for Photochemical Oxidants National Air PoUution Administration Pub. No. AP-63, U.S. Government Printing Office,... 

Fig. 3. Schematic diagram of a deterministic air quality model, showing the model components and interactions (1) where each of the boxes involves a large...

K. L. Demerjian, "Photochemical Diffusion Models for Air QuaUty Simulation Current Status," in Proceedings of the Conference on the State of the Art of Assessing Transportation-Kelated Air Quality Impacts, Oct. 22—24, 1975, Transportation Research Board, Washington, D.C., 1975. 

Pinal Air Quality Management Plan, 1982 rev.. South Coast Air QuaUty Management District and Southern California Association of Governments,... 

A. C. Lloyd and co-workers. Development of the EESTAR Photochemical Air Quality Simulation Model and Its Evaluation Relative to the EARPP Data Base, Environmental Research and Technology Report, No. P-5287-500, West Lake Village, Calif., 1979. 

J. W. Scales, Air Quality Instrumentation, Vols. I and II, Instrument Society of America, 1974. 

J. D. Benson and co-workers. Effects of Gasoline Sulfur on Mass Exhaust Emissions—-Autoj Oil Air Quality Improvement Research Program, SAE 912323, Society of Automotive Engineers, Warrendale, Pa., 1991. 

ERA promulgated the basic set of current ambient air-quality standards in April 1971. The specific regulated pollutants were particulates, sulfur dioxide, photochemical oxidants, hydrocarbons, carbon monoxide, and nitrogen oxides. In 1978, lead was added. Table 25-1 enumerates the present standards. 

Prevention of Significant Deterioration (PSD) Of aU the federal laws placing environmental controls on industiy (and, in particular, on new plants), perhaps the most confusing and restrictive are the limits imposed for the prevention of significant deterioration (PSD) of air quahty. These limits apply to areas of the countiy that are already cleaner than required by ambient air-quality standards. This regula-toiy framework evolved from judicial and administrative ac tion under the 1970 Clean Air Act and subsequently was given full statutoiy foundation by the 1977 Clean Air Act Amendments. 

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