Welcome to the State of California 

Indoor Radon Program   

The Indoor Radon Program, within the Environmental Management Branch, seeks to reduce the health risk from radon exposure by increasing awareness, identifying areas of high radon potential, and encouraging all Californians to test their homes for radon, fix their homes if they have a radon problem, and build new homes radon-resistant. Test. Fix. Save a Life.  

Radon Topics

Radon News

What is Radon?
How Radon Gets into Homes
Testing Your Home For Radon
Become A Certified Radon Service Provider
California Test Results
Radon Potential Reports
Radon and Real Estate
Radon and Schools
Radon and Health Care Practitioners
Building Radon-Resistant
Radon and Water
Regulations and Standards
Contact Us


Radon News

Aliso Canyon Gas Leak and radon Information 


2015 County Winter Radon Survey - NOW CLOSED

All free test kits available During the 2015 Survey have been claimed.

Thank you to the many California residents who have participated. We have successfully distributed all test kits for this survey! All free test kit requests placed before Friday, April 1 will be honored.

Due to unforeseen postal delivery days, many test kits have not arrived to the lab on time and could not be tested. If your test kit results were affected by USPS delivery delays, you are still eligible to receive a replacement by calling Alpha Energy Labs at 1-800-324-5928. CDPH is currently inquiring with the US Postal Service on the reasons for the delays. If your test was affected, we sincerely apologize for the unforeseeable inconvenience.

 Test results will be sent to you approximately 3 weeks after you return the test. You can also Check your test results here once they are available.  

Learn More:
Last modified on: 4/1/2016 2:17 PM