Radon is an odorless, invisible radioactive gas that naturally occurs through the breakdown of uranium in soil, rock and water. Radon gas may enter the indoor air of a basement or lower level of a building through cracks or holes in the foundation, walls, drains, or sump pump openings. Exposure to elevated levels of radon may lead to cancer, and smoking increases the risk of developing cancer.
GSA's radon policy establishes action levels (for radon in air) of 4 picoCurie per Liter (pCi/L) for childcare centers and residential buildings and 25 pCi/L for all other spaces or occupancies in GSA-controlled Federal and leased facilities. These action levels are based on standards and guidance recommended by the U.S. Environmental Protection Agency, Occupational Safety and Health Administration, Nuclear Regulatory Commission, and American Council of Governmental Industrial Hygienists. Facilities with radon test results above GSA-specified action levels must undergo mitigation in accordance with EPA-recommended methods. GSA's policy also establishes requirements for radon testing by GSA and lessors.