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  • Radon Testing: Should You Do It?

    Sure, you understand that radon is dangerous. But there’s a more important fact about the cancer-causing gas that you should know: Whether or not it’s in your home.

    Radon is the second leading cause of lung cancer, right behind smoking, as well as the number one cause of lung cancer among non-smokers.

    • Radon is common in homes across the country, and it could be in yours. Testing your home for radon is simple. Here’s what to know and how to get started.

      What is radon?

      Radon is a radioactive gas that you can’t see, smell or taste. It occurs naturally in the atmosphere in small amounts but when outdoors, it generally disperses quickly and isn’t a health issue.

      What causes radon?

      Radon forms when radioactive metals—uranium, thorium or radium—break down in rocks, soil and groundwater.¹

      How dangerous is radon?

      According to the American Lung Association, radon is the second-leading cause of lung cancer behind smoking.² Radon poisoning causes thousands of deaths per year—more than drunk driving and home fires combined.³

    • illustration of a house with radon in it

    • Where is radon found?

      Radon can be found all across the U.S. and around the world. When it’s released into the air, it quickly dilutes. When it seeps into buildings or homes through cracks, gaps or holes in the foundation, it becomes contained—and it lingers.

      The Environmental Protection Agency estimates that nearly 1 in 15 homes has elevated radon levels.³

    • How do I know if my home has radon?

      Although some areas of the country have, on average, higher levels of radon than others, serious levels exist in every state. What’s more, your neighbor’s radon level can vary drastically from your own. The only way to be sure of your home’s radon level is to have it tested with a radon inspection.

      Did you know that radon testing and radon mitigation is now often a condition of sale during real estate transfers? Test for safe radon levels and address any problems proactively so your family can breathe in the benefits, too.

      How do I test for radon at home?

      Knowing how to test for radon is very important. Purchase a DIY radon test online or at your local home improvement store for as little as $10. Or, hire a qualified professional tester, which can be more expensive. Expect to pay around $150 or more for a professional radon test.

      Testing for radon can take anywhere from a couple days to several months, as levels can vary not just season to season, but also hour to hour.

      However, a short-term (two- to 90-day) DIY radon test is easy and should only take a few minutes of your time. Once you have the test in-hand, find an undisturbed location in the lowest lived-in level of your home, keeping outside windows and doors closed as much as possible during the testing time. Follow the instructions on your testing kit for installation.

      What do I do with my home radon test results?

      • If your home tests at 4 picocuries per liter (pCi/L) or higher, the EPA recommends installing a mitigation system.³ Hire a qualified radon contractor to install a pipe-and-fan system to pull the radon from under your home and vent it outdoors. The average cost for a system is around $1,200.
      • If your home’s Radon level is lower than 4 pCi/L, the EPA recommends retesting again in two years—sooner if you make structural changes or occupy a previously unused level of your home.³

      Since no level of radon in homes is considered safe, some homeowners opt to mitigate when results top 2 pCi/L.

      Asking what radon is and where radon can be found is just the first step. The cost of reducing radon can depend on your home’s structure and the amount of radon you have. Usually, the issue can be fixed around the same cost as other common home repairs.


      1. National Center for Environmental Health

      2. American Lung Association

      3. Environmental Protection Agency

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