Radon is a naturally occurring, odorless, and colorless gas caused by the breakdown of uranium in soil, rock, and water. Long-term exposure to elevated radon levels creates an increased risk of lung cancer. North Carolina Radon Program and the EPA recommend that radon levels in excess of 4.0 pCi/L be reduced.

Because radon is a gas, it can enter buildings through openings or cracks in the foundation. Radon's primary hazard for humans is caused by inhalation of the gas and its highly radioactive, heavy-metallic decay products (polonium, lead, and bismuth), which tend to collect on dust in the air. The problem arises when these elements stick to the delicate cells lining the passageways leading into the lungs.

Radon has been identified as the second leading cause of lung cancer in the United States (second only to smoking). The EPA reports that radon causes approximately 21,000 lung cancer deaths every year in the United States.

Some scientific studies of radon exposure indicate that children may be more sensitive to radon than adults. This may be due to their higher respiration rate and their rapidly dividing body cells, which may be more vulnerable to radiation damage.

Every home should be tested for radon regardless of where the home is located, the age of the home, or foundation type. It should be tested whether or not the home is in an area that is “prone to having radon problems”.