Frequently Asked Questions about Radon

What is Radon?
 
Radon, Rn, is an extremely toxic, radioactive gas. It is atomic number 86, with an atomic weight of 222, a melting point of -71 degrees C and a boiling point of -62 degrees C. 
 
Radon is colorless, odorless, tasteless, and chemically inert. It can be condensed to a transparent liquid and to an opaque, glowing solid. Radon is used in various forms of cancer treatment, leak detection tracers and radiography. 
Where does Radon come from?
  
Radon-222 is the decay product of radium-226. Radon-222 and its parent, radium-226, are part of the long decay chain for uranium-238. Since uranium is essentially ubiquitous (being or seeming to be everywhere at the same time) in earth's crust, radium-226 and radon-222 are present in almost all rock and all soil and water. 

Radon is present outdoors and indoors. It is normally found at very low levels in outdoor air and in drinking water from rivers and lakes. It can be found at higher levels in the air in houses and other buildings, as well as in water from underground sources, such as well water. (American Cancer Society)
 
The amount of radon in the soil depends on soil chemistry, which varies from one house to the next. Radon levels in the soil range from a few hundred to several thousand of pCi/L (picocuries per liter) in air. The amount of radon that escapes from the soil to enter the house depends on the weather, soil porosity, soil moisture, and the suction within the house. 

According to the EPA, the average indoor radon level is about 1.3 picocuries per liter (pCi/L). People should take action to lower radon levels in the home if the level is 4.0 pCi/L or higher. The EPA estimates that nearly 1 out of every 15 homes in the United States has elevated radon levels.(American Cancer Society)
What are the health risks of Radon?
 
There are no immediate symptoms from exposure to radon. However, according to the Assessment of Risk for Radon in Homes (www.epa.gov/radon/risk_assessment.html), 21,000 lung cancer deaths in the United States are a result of indoor radon exposure. Lung cancer is the only known health effect linked to radon exposure. There is no evidence that other respiratory diseases are a result of radon exposure. 

Radon Risk If You Smoke

Radon Level Lifetime Exposure of 1,000 People* What to do: Stop Smoking and...
20 pCi/L About 260 people could get lung cancer Fix your home
10 pCi/L About 150 people could get lung cancer Fix your home
8 pCi/L About 120 people could get lung cancer Fix your home
4 pCi/L About 62 people could get lung cancer Fix your home
2 pCi/L About 32 people could get lung cancer Consider fixing between
1.3 pCi/L About 20 people could get lung cancer (Average indoor radon level)
0.4 pCi/L About 3 people could get lung cancer (Average outdoor radon level)

Note: If you are a former smoker, your risk may be lower.

*Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003).

Radon Risk If You Have Never Smoked

Radon Level Lifetime Exposure of 1,000 People* What to do: Stop Smoking and...
20 pCi/L About 36 people could get lung cancer Fix your home
10 pCi/L About 18 people could get lung cancer Fix your home
8 pCi/L About 15 people could get lung cancer Fix your home
4 pCi/L About 7 people could get lung cancer Fix your home
2 pCi/L About 4 people could get lung cancer Consider fixing your home
1.3 pCi/L About 2 people could get lung cancer (Average indoor radon level)
     
0.4 pCi/L   (Average outdoor radon level)

Note: If you are a former smoker, your risk may be higher.

*Lifetime risk of lung cancer deaths from EPA Assessment of Risks from Radon in Homes (EPA 402-R-03-003).

How does Radon get into your home?

Radon can be present in any of home, since almost all types of soil contains the natural decay of uranium.

Since radon is a radioactive gas, it can move up through the ground to the air above and into your home through cracks and other holes in the foundation. Then, the gas builds up as it is trapped inside your home. Radon can also enter your home through well water and building materials.

For more information, see www.epa.gov/radon/pubs/citguide.html
How do you test for Radon?

See "A Citizen's Guide to Radon" www.epa.gov/radon/pubs/citguide.html

If you are buying or selling a home, see "Home Buyer's and Seller's Guide to Radon" www.epa.gov/radon/pubs/hmbyguid.html

Where can you find more information?

  • The Environmental Protection Agency's website, www.epa.gov/radon
  • Kansas State University's radon information hotline, 1-800-55RADON (557-2366)
  • Kansas State University's test kit hotline, 1-800-SOSRADON (767-7236)
  • Kansas State University's Radon Fit-It Hotline, 1-800-644-6999
  • Safe Drinking Water Hotline, 1-800-426-4791

EPA Map of Oregon Radon Zones