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Indoor Air Quality (IAQ) Section


Radon is a naturally occurring gas found in soil, rocks, and water throughout California and the world. Radon has no color, odor, or taste. The gas can move  into homes, schools, and other buildings from the ground, and this ground source is our largest exposure to naturally occurring radiation. The California Department of Conservation has geographic information and maps of indoor radon potential for different areas in the state.

Radon leaks inside buildings through cracks and holes in the slab or foundation or can come through the water supply. The air pressure in the ground is usually higher than in buildings, so the outside pressure pushes radon gas through small openings in a building’s structure. The health effects of radon stem from radiation-induced cancer.

More information about radon can be found at the links below:

CDPH Indoor Radon Program

U.S. EPA Citizen's Guide to Radon: The Guide to Protecting Yourself and Your Family from Radon

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