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Radon in Homes and Buildings

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This page provides an overview of radon in homes and buildings.

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You can't see radon. You can't smell it or taste it. But it may be a problem in your home.

Radon is a radioactive gas. It comes from the natural decay of uranium that is found in nearly all rock and soils. Radon usually moves from the ground up and migrates into homes and other buildings through openings in any ground contact floor or wall. Buildings trap radon inside, where it accumulates and may become a health hazard. Any home or building may have a radon problem, including new and old homes, well-sealed and drafty homes, and homes with or without basements.

Approximately 55 percent of our exposure to radiation comes from radon.

Radon is the second leading cause of lung cancer in the United States, with more than 20,000 Americans dying each year from radon-related lung cancer.

Only smoking causes more lung cancer deaths and smokers exposed to radon are at an even higher risk than nonsmokers.

Radon can be detected with a simple test and an elevated radon level can be remedied.

Radon in the air is measured in pico curies per liter (pCi/L). Where radon levels are four pCi/L or higher, the U.S. Environmental Protection Agency and the U.S. Surgeon General recommend that homeowners take action to reduce the radon level. It is estimated that nearly one in 15 American homes has a radon level that should be reduced. Testing your home is the only way to know.

Who is protecting you

U.S. Environmental Protection Agency(EPA)

EPA drives the national commitment to educate citizens about residential radon risks. To achieve this goal, the Agency coordinates regional and state-level efforts to reduce exposure to radon.

The States

Individual states work closely with EPA to inform the public about how to reduce radon risks. Also, states work closely with two non-governmental organizations, the National Radon Safety Board (NRSB) and the National Environmental Health Association (NEHA), to train and qualify local radon services providers (in measurement and mitigation), and approve radon-testing laboratories.

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What you can do to protect yourself

Testing for radon is easy and only takes a few minutes. There are many kinds of low-cost, “do-it-yourself ” radon test kits available by phone, online and in many retail outlets. You can also hire a professional to do the testing. If an elevated radon level is detected in your home, you can reduce it in a variety of ways. The preferred radon reduction technique is an activated soil depressurization (ASD) system. Installation also requires the sealing of unwanted entry points for the ASD system to function effectively. An ASD system is basically a vent pipe with an inline centrifugal fan that operates continuously to vent radon (and other soil gases) from beneath the house.

For more information about radon, its risks, and what you can do to protect yourself, or to request a free copy of EPA’s “A Citizen’s Guide to Radon”, call the National Radon Hotline at 1-800-SOS-RADON or contact your state’s radon office.

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March 30, 2012. U.S. Environmental Protection Agency
Visit this page to learn more about radon and what you can do about high radon levels in your home, get answers on the most frequently asked radon questions and discover EPA’s radon program. 
Radon Information Resources
March 30, 2012. U.S. Environmental Protection Agency, Radon
This site has information on how to get more information on radon, including how to find a qualified radon service professional.
Hazardous Materials and Waste Management Division – Radiation Program exit EPA
Colorado Department of Public Health and Environment. [accessed on March 30, 2012]
Learn about the Colorado radon program and get links to other radon websites.
Welcome to the National Radon Safety Board exit EPA
March 30, 2012. National Radon Safety Board
Get links here to radon-related websites, including information on radon detecting services and devices.
National Radon Proficiency Program exit EPA
March 30, 2012. National Environmental Health Association
This page has radon links and information on finding certified individuals, device evaluations and how to learn more about the National Radon Proficiency Program.
Radon and Cancer: Questions and Answers exit EPA
March 30, 2012. U.S. National Institutes of Health, National Cancer Institute
This page answers frequently asked questions about radon and radon-related health concerns.

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