The most common indoor air pollutants include:
Particulate matter (PM): PM is a mixture of solid particles and liquid droplets found in the air. It can come from a variety of sources, including outdoor air pollution, wood burning, and cigarette smoke.
Volatile organic compounds (VOCs): VOCs are chemicals that evaporate easily at room temperature. They can come from a variety of sources, including building materials, furnishings, and household cleaning and maintenance products.
Carbon monoxide (CO): CO is a colorless, odorless gas that can be produced by combustion appliances, such as furnaces, water heaters, and gas stoves.
Radon: Radon is a radioactive gas that can come from the ground and enter homes through cracks in the foundation.