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Radon Gas

* Researchers at Portland State University's Geology Department prepared these estimates. We'll update these data as as more people test their homes for radon, and those results become available for analysis. 

Regardless of your home's zip code or where it falls on the maps above, the only way to know if your home has a radon problem is to test.


Fortunately, radon levels in homes, schools and buildings can be measured with a simple test. Testing for radon is easy, inexpensive and effective. If high radon levels are found, they can be reduced by using proven mitigation techniques.

Order your American Lung Association test kit here.

What is Radon?

Radon is a naturally occurring radioactive gas that is colorless, odorless, and tasteless. It is formed by the natural breakdown of uranium in rock, soil and water.

Radon gas moves up through the soil and can be drawn into our homes by slight pressure differences. Once inside, radon can become trapped and build up to unsafe levels.

The U.S. Surgeon General warns that radon is the second leading cause of lung cancer after cigarette smoking and the number one cause of lung cancer in non-smokers. The U.S. Environmental Protection Agency estimates that radon causes around 20,000 deaths from lung cancer annually in the United States.