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.  

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Radon News

Aliso Canyon Gas Leak and radon Information                   

Winter Radon Survey - Free Test Kits Available in Santa Clara, Fresno, and Madera Counties

The California Department of Public Health (CDPH) and California Geological Survey (CGS) are asking for your help in a radon-testing project. Through this program residents of Santa Clara, Fresno, and Madera counties can test their homes this winter at no cost. Personal data will not be collected and your test results will remain anonymous.  

Residents of Santa Clara, Fresno and Madera counties can order a free radon test kit. Some residents in those counties will be receiving letters in the mail reminding them of this opportunity. Residents of other counties can purchase a test kit for $7.95.

The goals of this program are:

1.   Inform you of the health risks from radon, which is the second leading cause of lung cancer in the U.S.

2.   Give you a way to test for radon in your home at no cost to you

3.   Improve the knowledge of radon in your county 

The test is very simple to do and does not interfere with your normal household activities. It involves placing the test kit in your home for two days. More details will be provided with your test kit.


To participate and receive A free short-term test kit visit the Alpha Energy laboratory web page: 

County Winter Radon Screening ProgramThis web link will take you to an external site

Programa de Invierno de Detección de Radón del CondadoThis web link will take you to an external site

Or call Alpha Energy Laboratories at (800) 324-5928.

 Your free test kit will be sent within 48 hours.

Due to the high volume of test kit requests, the webpage order form may be running slowly. If you encounter problems, you can also email your test kit request, including your mailing address, to radonprogram@cdph.ca.gov. Thank you! 

 There are a limited number of test kits available for Each county.

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.  

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Last modified on: 1/28/2016 11:37 AM