Indoor Air Pollution

Abstract

People spend most of their time indoors, so the composition and quality of indoor air has a significant impact on human health. Because people's time is often divided between home and work, it is important to examine air quality in both residences and workplaces. Sources of indoor air pollution include outdoor air that infiltrates indoors and indoor emissions. Outdoor air contains the constituents of smog, but some of these constituents dissipate quickly indoors because of the lack of UV radiation to regenerate them indoors. Major indoor sources of pollution include stoves, heaters, carpets, fireplaces, tobacco smoke, motor vehicle exhaust from garages, building materials, and insulation. In developing countries, major sources of indoor air pollution include the products of solid biofuel and coal combustion for home heating and cooking. Such pollution is responsible for significant premature mortality worldwide. Whereas indoor air pollution is often regulated in workplaces, it is not regulated in residences. In this chapter, characteristics, sources, and regulation of indoor air pollution are discussed. Pollutants in Indoor Air and Their Sources Throughout the world, people spend most of their time indoors. One study found that, in the United States, about 89 percent of time was spent indoors, 6 percent was spent in vehicles, and 5 percent was spent outdoors (Robinson et al., 1991). A study of less developed countries showed that people in urban areas spent about 79 percent of their time indoors, and those in rural areas spent about 65 percent of their time indoors (Smith, 1993). Because people breathe indoor air more than outdoor air, an examination of indoor air is warranted. Nearly 1.6 million people worldwide die each year prematurely from indoor air pollution (not including smoking), making it one of the leading causes of death worldwide (World Health Organization (WHO), 2005). Most of these deaths are due to indoor burning of solid biofuels and coal for home heating and cooking with inefficient cook stoves and heaters.