Find Certified Radon Testers Near You

Radon is a naturally occurring radioactive gas that forms from the decay of uranium in soil and rock. It is colorless, odorless, and tasteless — making it undetectable without testing. It seeps up through the ground and can accumulate to dangerous levels inside homes and buildings.

Radon is the second leading cause of lung cancer in the United States, responsible for about 21,000 deaths per year according to the EPA. Any home can have a radon problem. The only way to know your radon level is to test, and the EPA recommends testing all homes below the third floor.

The EPA recommends taking action to reduce radon if your home level is 4 pCi/L (picocuries per liter) or higher. The average indoor radon level is about 1.3 pCi/L. Even levels between 2–4 pCi/L present some risk, and mitigation should be considered.

Test when you move into a new home, after any major renovation, or every two years as a general rule. If you have a mitigation system installed, test every two years to ensure it is working. The EPA also recommends retesting if you have made renovations or spend more time in lower levels of your home.

A radon tester measures your home's radon levels using specialized equipment and certified protocols. A radon mitigator installs systems (such as sub-slab depressurization) to reduce elevated radon levels. Some companies offer both services. NRPP and AARST credentials indicate certified professionals.

Look for providers certified by NRPP (National Radon Proficiency Program) or AARST-NRPP. Check that they follow EPA and state guidelines. Ask whether they use third-party lab analysis, provide written reports, and whether they warranty their mitigation systems. Our directory lists providers by location to help you find someone nearby.