Radon, a radioactive gas that occurs naturally in most soil, is the second-leading cause of lung cancer among smokers and the number-one cause among non-smokers. It is responsible for more than 20,000 lung cancer deaths in the U.S. each year, according to EPA estimates. January is National Radon Action Month, and the Indiana State Department of Health (ISDH) is urging homeowners to test their homes for radon because this tasteless, colorless and odorless gas can build up in homes without residents’ knowledge. Indiana residents can purchase a short-term test kit for as little as $15 from the American Lung Association through its website. Test kits also can be purchased at most home improvement and hardware stores and through some online retailers. Because radon has no taste, smell or color, a home must be tested to find out how much radon is in the air. There is no safe level for radon, but the EPA and U.S. Surgeon General recommend fixing homes that have levels at or above 4pCi/L (picocuries per liter). More than two-thirds of Indiana counties have predicted average indoor radon levels of 4 pCi/L, according to the EPA. (A map of those counties can be found at https://www.in.gov/isdh/files/Radon_Township%20aggregate%202002_2017.pdf) To learn more about radon, visit the ISDH’s radon page at http://www.in.gov/isdh/24346.htm and the EPA’s “A Citizen’s Guide to Radon” at https://www.epa.gov/radon/publications-about-radon.