Radon is a radioactive gas that forms naturally when uranium, thorium, or radium, which are radioactive metals break down in rocks, soil and groundwater. People can be exposed to radon primarily from breathing radon in air that comes through cracks and gaps in buildings and homes.

What causes radon gas in homes?

Radon is a radioactive gas that has been found in homes all over the United States. It comes from the natural breakdown of uranium in soil, rock, and water and gets into the air you breathe. Radon typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation.

Where is radon most commonly found?

Radon levels are usually higher in basements, cellars and living spaces in contact with the ground. However, considerable radon concentration can also be found above the ground floor.