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Indoor Air Quality (IAQ)

Learn About Indoor Air Quality in Tribes

What is IAQ?

Indoor air quality (IAQ) is a term used to describe the level of air pollution in homes and other indoor spaces. Indoor air pollutants are chemical, physical, or biological pollutants, such as secondhand smoke, chemicals in carpeting and treated wood, paint gases, mold and dust mites, among others. When these pollutants are present in high concentrations, they can put our health at risk by causing or exacerbating health problems.

Indoor air pollutants may be present at levels two to five times higher — and occasionally more than 100 times higher — than outdoor levels of pollutants. The average person spends nearly 90 percent of his or her time indoors.

A picture of a multi-story home linking to the IAQ House homepage

Get a quick glimpse of some of the most important ways to protect the air in your home, tour the Indoor Air Quality (IAQ) House. Room-by-room, you'll learn about and how to address key pollutants. Read "Care for Your Air."

Ensuring healthy IAQ by minimizing indoor air pollutants is important. Poor IAQ can have serious repercussions on an individual’s health. Children, the elderly, and those with compromised immune systems are particularly susceptible to pollutant exposure. Health effects include respiratory problems (including asthma), chronic fatigue, headaches and cancer. In rare cases of chronic toxic pollutant exposure, neurological, reproductive (e.g., reduced fertility) and developmental problems can result.

Fortunately, IAQ can be managed. Learn more about how to manage the sources of indoor air pollutants and monitor IAQ.


EPA's Care for Your Air brochure provides quick and simple overview of some key indoor air pollutants including radon, secondhand smoke, asthma triggers, volatile organic compounds, molds and combustion pollutants. The brochure unfolds into a poster that features action steps to improving indoor air. Find out more about Indoor Air Quality.

The American Lung Association’s (ALA) Health House Program Exit provides simple tips for improving IAQ.