Radon Levels in Ohio
Ohio is classified as an EPA Zone 1 state with a high risk for radon. Average indoor radon levels range from 2 to 6 pCi/L, and approximately 31% of Ohio homes test above the EPA action level of 4.0 pCi/L.
Ohio Radon Summary
High Radon Risk State
Ohio is among the higher-risk states for residential radon. The Ohio Department of Health strongly recommends that all residents test their homes. If you have not tested your home, consider ordering a test kit or radon detector today.
Key Facts About Radon in Ohio
- Ohio has widespread high radon levels
- The shale formations in eastern Ohio contribute to elevated radon
- Ohio EPA operates an active radon program
- Ohio requires disclosure of known radon test results in home sales
Ohio Testing Requirements & Recommendations
Ohio requires radon disclosure in real estate transactions. Testing recommended for all homes.
Ohio's diverse geology requires local expertise for effective mitigation.
Major Cities in Ohio
Radon levels can vary significantly within Ohio depending on local geology. All residents — regardless of city — should test their specific home, as neighborhood-level radon varies independently of broader state and county averages.
What Should Ohio Residents Do?
Test Your Home
Use a short-term charcoal test kit ($15–$25) for an initial reading, or a continuous radon detector for ongoing monitoring. Test in your basement or lowest livable area.
Understand Your Result
If your result is below 2.0 pCi/L: monitor periodically. Between 2.0–4.0 pCi/L: consider mitigation. Above 4.0 pCi/L: the EPA recommends mitigation. Above 8.0 pCi/L: take action promptly.
Hire a Certified Contractor if Needed
Look for NRPP or NRSB-certified radon mitigation contractors in Ohio. Mitigation systems typically cost $800–$2,500 and can reduce radon levels by 50–99%.
Verify with a Follow-Up Test
After mitigation, test again to confirm the system is working. Retest every 2 years, or after significant home renovations.
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