Radon is a cancer-causing, radioactive gas. Radon is a naturally occurring radioactive gas released in rock, soil, and water from the natural decay of uranium. While levels in outdoor air pose a relatively low threat to human health, radon can accumulate to dangerous levels inside buildings. You can't see, smell, or taste it, but an elevated radon level in your home may be affecting the health of your family. Radon exposure is the second leading cause of lung cancer in the United States and the number one cause among non-smokers.

Radon is found all over the United States, and every state has found homes with elevated levels of radon. No area of the country is free from risk. Indeed, two homes right next to each other can have vastly different radon levels. Just because your neighbor's house does not have an elevated level of radon does not mean that your house will have a low radon level. Tests are the only way to determine if your home's radon level is below the EPA action level of 4 picoCuries per liter of air.