High concentrations of radon can cause lung cancer; in fact, radon is the second leading cause of this disease in the United States. Radon gas forms when the uranium found in water, rocks, and soil breaks down. Radon is then released into the dirt beneath your home and may enter it through cracks, gaps, and spaces (in floors and foundation walls), exterior air vents, fireplaces, furnaces, construction joints, etc.
Radon tests are relatively inexpensive. Most cost between $100 and $916 depending on whether you use a home testing kit or hire a professional company to come out and test all of the rooms of your home. You can typically correct most radon issues for $500 or less.
Costs vary greatly by region (and even by zip code). To get free estimates from local contractors, please indicate yours.