We’ve made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Radon

Radon

Radon is a naturally occurring radioactive gas that can cause lung cancer.
You can’t see or smell radon. Testing is the only way to know your level of exposure.  Radon can have a big impact on indoor air quality.

Radon Information for States and Tribes