Radon is a radioactive, colorless, odorless, tasteless gas that can manifest itself in buildings. It is created from decaying uranium or thorium. You cannot smell, taste or see radon.
Radon from natural sources can accumulate in buildings, particularly in enclosed areas like attics, basements and crawlspaces. 1 out of every 15 homes has high radon gas levels. Gunnison County is an high risk area for radon.
Radon exposes humans to radiation and negatively impacts indoor air quality. After cigarette smoking, radon is the second most frequent cause of lung cancer in the US. Radon gas contains radioactive particles that get stuck in your lungs every time you inhale. As the particles break down, they release radiation that damages your lung tissue, causing lung cancer and, in some cases, death. Radon causes an estimated 21,000 lung cancer deaths each year.
The EPA recommends testing all homes below the 3rd floor for radon. If radon levels are found to exceed EPA recommendations, a radon mitigation system can reduce radon levels by up to 99%.
For more information see:
EPA's Citizen's Guide to Radon
Kansas State University's National Radon Program Services
Inexpensive radon test kits are available from Kansas State University here (and many other places).