Radon is a colorless, odorless gas that can get trapped in houses. It contributes to your changes of getting lung cancer. It is the element with atomic number of 86 and the symbol or abbreviation, Rn.
Radon is created by the natural breakdown of uranium in soil and rocks. While it is found all over the U.S. and in many other parts of the world, some places produce more than others. But results in your home can be different than your neighbors. Homes with basements or underground sections with more exposure or enclosure within the ground and less circulation are more likely to be at risk. But radon can enter a home in many ways: cracks in the foundation or walls, gaps in the floor or around pipes, well water and other ways.
Radon doesn't have any perceptible signs. And it's fairly common. It's also a danger that you can reduce if you know about it. So, it makes sense to test for it. When you move into a new home, request a test. If you may be moving soon, you may wish to have a test you can show potential buyers. Homes are now sometimes built with radon reducing features, but even those homes should be tested initially.
You can have a test done professionally, or there are kits sold by mail order and in places like hardware stores or department stores with home hardware sections. Follow the directions on the kit. (The one I used had you hang two collectors in different parts of the basement for a few days.) Different kits can take differing amounts of time -- from two day tests to months. Then you send in the kits for testing.
Results are reported in pCi/L (picocuries per liter of air) or Becquerel (Bq). The lower the number, the safer. Levels of .4 pCi/L are normal outdoors; 1.3 pCi/L is considered normal for indoors. Between 2 and 4 pCi/L, the U.S. Environmental Protection Agency (EPA) recommends you consider methods of reducing it. At levels above 4 pCi/L, they recommend taking steps to reduce the radon. The United Nations' World Health Organization (WHO) says than 5 and 15 Bq/m3 (Becquerel per cubic meter) is the normal range for outdoors. It is the second leading cause of lung cancer and the cause of 3-14% of lung cancer depending on other factors depending on the region of the world. WHO says that countries recommend remediation at levels of 200–400 Bq/m3.
The U.S. Environmental Protection Agency (EPA) suggests retesting after awhile if the levels are borderline or about every two years if you've had a problem to check on remediation measures taken.
Radon is estimated to be responsible for about 20,000 lung cancer deaths in the U.S. each year. Your risk is even higher if you are also a smoker.
- The United Nations (UN)'s World Health Organization (WHO) on Radon and Cancer
- A Citizen's Guide to Radon by the U.S. Environmental Protection Agency (EPA) and their main page on radon
- Wikipedia's article on radon
- Consumer Reports Health.org on CR Quick Recommendations Radon test kits