Jan. 13, 2025—By now, you probably know about the link between smoking and lung cancer. But there's another risk factor for the disease that doesn't get as much attention: radon exposure.
In fact, radon is the leading cause of lung cancer in people who don't smoke. Here's what you need to know about radon, based on information from the American Lung Association, the Centers for Disease Control and Prevention (CDC) and the U.S. Environmental Protection Agency (EPA).
What is radon?
Radon is a radioactive gas that forms when certain metals break down underground. It can build up in homes and other buildings.
Homes with high radon levels have been found in all 50 states, according to the EPA.
Radon leaks in through cracks in the basement, crawl space, walls or foundation of your home. In some cases, radon may enter the home through well water or, rarely, certain building materials. It can happen in new buildings and in older homes—including those without basements.
How to test for radon
Testing is the only way to know the radon level in your home. Radon exposure has no symptoms, and the gas can't be seen, smelled or tasted.
The good news is that testing your home for radon is simple. You get a test kit, open the package, and leave it undisturbed in the lowest part of your house for between 2 and 90 days, depending on the type of test you use.
After doing that, you send the kit back to the testing company. You'll typically get the results in about two weeks. Many kits cost less than $25.
You can usually find radon test kits at the following sources:
- Hardware stores.
- Online.
- Your state radon office.
Another option is to hire a pro to conduct a radon test. Check your state's radon program for a list of qualified testing professionals.
CDC says it's especially important to test for radon if:
- Your house has never been tested before.
- Radon levels are not known.
- You're buying or selling a house.
- You are about to renovate or you just finished renovations.
For more information about radon testing, call the national radon hotline at 1.800.SOS.RADON (1.800.767.7236).
High radon levels? Take these steps
Luckily, it's possible to bring down dangerous radon levels. Professional radon fixers are called radon mitigators, and you can find them through your state's radon office or an online search. They can install a system that traps the radon gas and vents it to the outdoors.
Even if your radon levels aren't dangerously high, it's still a good idea to do what you can to keep radon low. Start with these tips from CDC:
- Seal up cracks. Use plaster or caulk to close any cracks in floors or walls.
- Increase air flow. Open the windows, when possible, and use fans to keep air moving. This can temporarily lower radon levels.
- Cover earth floors in crawl spaces with a high-density plastic sheet. Use a pipe and fan under the sheet to blow radon outside.
Breathe easier
Looking for more ways to clear the air in your home? Discover ways to counter six common causes of indoor air pollution.
Sources
- American Lung Association. "Radon." https://www.lung.org/clean-air/indoor-air/indoor-air-pollutants/radon.
- Centers for Disease Control and Prevention. "Radon and Your Health." https://www.cdc.gov/radon/about/index.html.
- Centers for Disease Control and Prevention. "Testing for Radon in Your Home." https://www.cdc.gov/radon/testing/index.html.
- U.S. Environmental Protection Agency. "Basic Radon Facts." https://www.epa.gov/system/files/documents/2023-01/Basic%20Radon%20Facts%20Factsheet.pdf.
- U.S. Environmental Protection Agency. "How Does Radon Get Into Your Home?" https://www.epa.gov/radon/how-does-radon-get-your-home.