Burlington, Vermont – A dangerous gas could be building inside Burlington-area homes right now as cold spring nights keep windows closed, allowing radon—known as the “invisible killer”—to accumulate quickly indoors. The risk can increase within hours when homes remain sealed during sharp temperature drops common in early spring.
According to the U.S. Environmental Protection Agency, radon is a radioactive gas that forms naturally in soil and enters homes through cracks in foundations, basements, and crawl spaces. Vermont is considered a high-risk state, with testing showing roughly 30% to 40% of homes exceed the EPA action level of 4 picocuries per liter.
In Burlington and across Chittenden County, older homes with full basements are especially vulnerable. Communities including South Burlington, Essex, and Colchester often see elevated indoor readings this time of year as residents limit ventilation overnight. The Vermont Department of Health reports radon is the second leading cause of lung cancer in the United States, contributing to about 21,000 deaths annually.
Health officials emphasize that radon exposure has no immediate symptoms, making testing critical. Short-term test kits can return results within 48 to 96 hours, and mitigation systems can reduce indoor levels by up to 99 percent.
Residents are urged to test homes now as conditions through April continue to favor indoor buildup. Additional advisories may be issued as the risk persists into early summer.
