This paper provides a background on the issue of indoor air quality. It includes a discussion of
the financial, technical, legal, insurance and health-related aspects of unacceptable indoor air
quality (IAQ). It discusses the roles of ventilation system performance, pollutant sources and
human responses in determining acceptable indoor air quality as they relate to comfort, health and
chronic illness. Finally, it discusses some issues confronting those who seek to formulate and
implement policies to improve IAQ.