What is Radon?
Radon is a cancer-causing, radioactive gas. You cannot predict radon levels based on state, local or neighborhood radon measurements. Homes which are next to each other can have different indoor radon levels. Radon typically moves up through the ground and into your home through cracks and other openings in the foundation. 
You cannot see, smell or taste radon, but it may be a problem in your home. When you breathe air containing radon, you increase your risk of getting lung cancer. In fact, the Surgeon General of the United States has warned that radon is the second leading cause of lung cancer in the United States today. The EPA and the Surgeon General recommend testing all homes for radon.  

The EPA recommends that you fix the home when the radon level is 4 picoCuries per liter (pCi/L) or more. For more information about radon, visit www.epa.gov/iaq/radon.