Radon and Your Health: Get The Facts

What is Radon?

Radon is an odorless and invisible radioactive gas released when some naturally occurring radioactive materials break down in rocks, soil and water and can build up to dangerous levels inside homes or buildings.

How Does Radon Get In My Home?
Illustration of two-story home with basement

Any home can have a radon problem. Whether your home is drafty or well-sealed, radon can still build up and get trapped inside.  Radon can enter the home through several ways.

  • Cracks in solid floors and walls
  • Construction joints
  • Gaps in suspended floors
  • Gaps around service pipes
  • Cavities inside walls
  • The water supplies
How Does Radon Affect My Health?
Female doctor viewing chest xray

When you breathe in radon, radioactive particles from the decay of radon gas can get trapped in your lungs. Over time, these radioactive particles increase the risk of lung cancer. It may take years before health problems appear.

Radon is the second leading cause of lung cancer after cigarette smoking.  The U.S. Environmental Protection Agency (EPA) and the Surgeon General’s office estimate radon is responsible for more than 20,000 lung cancer deaths each year in the U.S.  Currently, there are no conclusive data on whether children are at greater risks than adults from radon.

The chances of getting lung cancer are higher if your home has elevated radon levels and you smoke or burn fuels that increase indoor particles. Your chances of getting lung cancer from radon depend mostly on:

  • How much radon is in your home–the location where you spend most of your time (for example, the main living and sleeping areas).
  • The amount of time you spend in your home
  • Whether you are a smoker or have ever smoked
  • Whether you burn wood, coal, or other substances that add particles to the indoor air

For more information about health concerns, see EPA’s Health Risk of Radonexternal icon web page.

What Can I Do About Radon?

Steps you can take to measure and reduce radon levels include:

Four measures to track Radon in your home or office

What Other Things Can I Do To Reduce My Exposure To Radon?

The U.S. Department of Housing and Urban Development external icon recommends additional actions you can take to reduce high radon levels in your home and protect yourself from an increased risk of lung cancer.

Man smoking in a smoke cloud
  • Stop smoking and discourage smoking in your home.
    • Smoking significantly increases the risk of lung cancer from radon.
  • Increase air flow in your house by opening windows and using fans and vents to circulate air.
    • Natural ventilation in any type of house is only a temporary strategy to reduce radon.
  • Seal cracks in floors and walls with plaster, caulk, or other mate­rials designed for this purpose.
    • Contact your state radon officeexternal icon for a list of qualified contractors in your area and for information on how to fix radon problems yourself. Always test again after finishing, to make sure you’ve fixed your radon problem.
  • Ask about radon-resistant construction techniquesexternal icon if you are buying a new home.
    • It is almost always cheaper and easier to build these features into new homes than to add them later.

Radon can also be a problem in schools and workplaces. Find out if your schools, daycares and childcare facilities, and workplaces have been tested for radon (visit https://www.epa.gov/radonexternal icon or https://www.epa.gov/radon/radon-schoolsexternal icon for more information).

Page last reviewed: January 14, 2021