Radon is a naturally occurring, invisible, odorless gas that is harmlessly dispersed in outdoor air, but when trapped in buildings, can be harmful at elevated levels. It is the second leading cause of lung cancer and present in elevated levels in about 50% of area homes. The only way to know if you have an elevated level in your home is to test. Act now as winter is the best time to test for radon gas. If your home has unsafe concentrations of radon gas, it can be fixed. Coupons for free test kits may be obtained at the Health District office.