Indoor Air Quality: An Overview of Policy and Regulatory Issues

Historically, nonindustrial indoor environments-residential, commercial, institutional, and public buildings-have been considered relatively nonhazardous. During outdoor air pollution episodes, small children and individuals with respiratory illnesses are encouraged to stay indoors. Although this practice may be good advice if the goal is to reduce human exposures to photochemical oxidants (such as ozone), there is increasing evidence that concentrations of many other air pollutants are routinely elevated in private and public buildings.' Among these airborne contaminants are passive tobacco smoke, formaldehyde, carbon monoxide, nitrogen dioxide, radon decay products, asbestos fibers, respirable particles, volatile organic compounds, bacteria, viruses, fungi, and aeroallergens (see Table 1). The potential hazards of indoor air pollution have only recently attracted the attention of scientists, engineers, physicians, regulatory officials, industrial associations, and environmental groups. As a result, there is more discussion but little data by which to evaluate health risks for most contaminants.