Radon Levels in Arizona
Arizona is classified as an EPA Zone 2 state with a moderate risk for radon. Average indoor radon levels range from 1 to 3.5 pCi/L, and approximately 11% of Arizona homes test above the EPA action level of 4.0 pCi/L.
Arizona Radon Summary
Key Facts About Radon in Arizona
- Northern Arizona (Flagstaff area) has higher radon levels than the south
- Desert soil contains naturally occurring uranium that decays to radon
- Newer construction with tighter building envelopes can concentrate radon
Arizona Testing Requirements & Recommendations
No statewide requirement. Arizona Department of Health Services recommends testing.
Arizona's dry conditions can actually facilitate radon movement through soil.
Major Cities in Arizona
Radon levels can vary significantly within Arizona 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 Arizona 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 Arizona. 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.
Some links are affiliate links. Learn more.
