EPA Radon Articles
Radon is a naturally occurring, invisible, odorless gas that comes from deposits of uranium in soil, rock, and water. It is harmlessly dispersed in outdoor air, but when trapped in buildings, can be harmful, especially at elevated levels. Radon is a radioactive decay product of radium, which is itself a decay product of uranium. Uranium and radium are both common elements in soil.
The primary source of high levels of radon in homes is the surrounding soil. Radon has been found in elevated levels in homes in every state, and the U.S. Environmental Protection Agency estimates that as many as one in 15 homes across the U.S. have elevated radon levels.
Warm air rises. When this happens in your home, it creates a vacuum in the lower areas of the house. Nature hates a vacuum, so something must rush in to fill it. In the case of your home, air seeps in from the soil around and under the house, and some air is sucked in through openings (cracks, doors, windows) on the lower levels. Radon gas enters the same way air and other soil gases enter the home; through cracks in the foundation floor or walls, hollow-block walls, and openings around floor drains, pipes and sump pumps.
Exposure to radon is the second leading cause of lung cancer in the U.S. Radon can be inhaled into the lungs, where it undergoes radioactive decay. As it decays, radon releases tiny bursts of energy called alpha particles, which can harm sensitive lung tissue by damaging the DNA. This damaged DNA can lead to lung cancer.
Radon is measured in picocuries per liter of air (pCi/L), a measurement of radioactivity. The U.S. EPA and the Centers for Disease Control and Prevention recommend that homes with radon levels 4 pCi/L, or greater, be fixed.
Radon is the 2nd leading cause of lung cancer. Approximately 21,000 people die each year due to Radon!