Dallas, Texas – A dangerous gas could already be building inside homes across North Texas as shifting spring temperatures keep windows closed overnight, allowing radon—known as the “invisible killer”—to accumulate indoors within hours. The risk increases quickly when airflow is limited during cooler nights and early morning hours.
According to the U.S. Environmental Protection Agency, radon is a radioactive gas that forms naturally in soil and can enter homes through foundation cracks, slab floors, and pier-and-beam structures common across the region. Texas is generally considered a moderate radon-risk state, but elevated levels have been detected across North Texas, particularly in Dallas, Tarrant, and Collin counties, where some homes exceed the EPA action level of 4 picocuries per liter.
In Dallas-Fort Worth and surrounding communities including Plano, Arlington, and Frisco, homes can trap indoor air during overnight temperature drops, allowing radon concentrations to rise. Health officials warn that radon is the second leading cause of lung cancer in the United States, linked to about 21,000 deaths annually.
Radon exposure produces 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 when properly installed.
Residents are urged to test homes now as conditions through April continue to support indoor buildup. Additional advisories may be issued as risks persist into early summer across North Texas.
