NC Radon Program

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Watch news story on granite counter tops from station WRAL, Raleigh, NC

Is there a danger of radon gas or associated radiation being emitted from granite countertops?

Granite is a naturally occurring igneous rock, meaning that it was formed by the cooling of molten rock.  It is quarried and processed to produce commercial products such as countertops. It is possible for any granite sample to contain varying concentrations of uranium that can produce radon gas, a source of alpha and beta particles and gamma rays. Some granite used for countertops may contribute variably to indoor radon levels.  At this time, however, we do not believe sufficient data exists to conclude that the types of granite commonly used in countertops are significantly increasing indoor radon levels. Some granite may emit gamma radiation above typical background levels.  While radiation levels are not typically high, measurement of specific samples may reveal higher than expected levels on a case-by-case basis.

What advice does the NC Radon Program have for consumers who have granite countertops?

The best way to determine if your house has a radon problem, regardless of the source, is to test the air.  Because radon is a gas, the health concern comes from inhaling air with radon gas. While natural rocks such as granite may emit radon gas, the levels of radon attributable to such sources are not typically high. The NC Radon Program believes the principal source of radon in homes is soil gas that is drawn indoors through a natural suction process. To reduce radon risk, you should first test the air in your home to determine the radon level.

There are two options for testing your home for radon: you can purchase a test kit and test your home yourself or you can hire a certified measurement provider to test your home for you.  The test kits can be purchased online or at a home improvement store for $10-$25.  We also are currently selling them on our website for $4-$8.  Click here to purchase a radon test kit.  If you choose to hire a certified measurement provider, the testing cost will be $100-$150.  A specially-trained and qualified professional may be equipped to test for lesser sources (such as granite or diffusion from drinking water) when evaluating the nature and source of your home's radon problem.  For list of the certified measurement providers in your area, click here.

If your home has a high radon level, a level of 4 picocuries per liter (pCi/L) of air or more, there are ways to mitigate or reduce the radon level in almost any home. The key to reducing risk is to test your home for radon and then make decisions as appropriate.  We recommend using a certified mitigator to reduce radon levels in your home.  For a list of certified mitigators in NC, click here.

Are the levels of radon in granite dangerous to humans or animals?

While radon levels attributable to granite are not typically high, there are simply too many variables to generalize about the potential health risks inside a particular home that has granite countertops. It is prudent to limit your family's exposure to radon whenever possible.  EPA recommends that indoor air have a radon level as far below 4 pCi/L of air as possible. There are easy ways to test the air in your home for radon, and high radon levels can be reduced with proven and inexpensive technology.  The NC Radon Program believes the most significant source of radon risk is soil gas.  Regardless of source, all homes should be tested for radon.

Has the Environmental Protection Agency (EPA) done studies on radon in granite countertops?

There are a few studies that have conducted limited research on radon in granite countertops. EPA will continue to review this research. The U.S. Surgeon General and EPA recommend that all homes be tested for radon in indoor air. It's easy and inexpensive to test homes with do-it-yourself radon test kits that are commonly available at the retail level and on-line.

Does the EPA have plans to conduct a study on radon in granite countertops?

EPA will continue to monitor and analyze the evolving research on this issue and will update its recommendations as appropriate.