Radon is a colorless, odorless, radioactive gas that seeps into buildings from soil and bedrock, posing serious health risks through prolonged exposure. Radon forms from the natural decay of uranium in earth materials and accumulates in basements and lower levels where soil contact is greatest. It is the second leading cause of lung cancer after smoking in the United States.
Detection and Risk Levels
The EPA recommends testing for radon in all homes, particularly in areas designated as Zone 1 or Zone 2 radon potential. Indoor radon levels above 4 picocuries per liter (pCi/L) require remediation. Short-term tests measure levels over 2 to 7 days, while long-term tests provide 90-day averages for more accurate assessment.
Mitigation Systems
Radon mitigation typically involves sub-slab depressurization systems that vent soil gas safely above the roofline. Additional strategies include sealing foundation cracks, improving basement ventilation, and installing heat recovery ventilators. Properly designed and maintained mitigation systems can reduce radon concentrations by 99%, bringing levels below 2 pCi/L and significantly lowering lung cancer risk.