“Indoor air quality” refers to the quality of the air in a home, school, office, or other building environment. Most pollutants affecting indoor air quality come from sources inside buildings, although some originate outdoors. Typical pollutants of concern include combustion products such as carbon monoxide, particulate matter, and environmental tobacco smoke; substances of natural origin such as radon; biological agents such as molds; pesticides; lead; asbestos; ozone (from some air cleaners); and various volatile organic compounds from a variety of products and materials. Indoor concentrations of some pollutants have increased in recent decades due to such factors as energy-efficient building construction and increased use of synthetic building materials, furnishings, personal care products, pesticides, and household cleaners.
The potential impact of indoor air quality on human health nationally is considerable, for several reasons. Americans, on average, spend approximately 90 percent of their time indoors, where the concentrations of some pollutants are often 2 to 5 times higher than typical outdoor concentrations. Moreover, people who are often most susceptible to the adverse effects of pollution (e.g., the very young, older adults, people with cardiovascular or respiratory disease) tend to spend even more time indoors. Health effects that have been associated with indoor air pollutants include irritation of the eyes, nose, and throat; headaches, dizziness, and fatigue; respiratory diseases; heart disease; and cancer.
