Radon is a radioactive gas that has been found in homes all over the United States. It comes from the natural breakdown of uranium in soil, rock, and water. Radon typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation.

Radon Testing Protocol

When a home is being tested for radon, it is important to control the environment as much as possible in order to yield accurate results. Below is a list of requirements, guidelines, and tips to ensure accurate readings.

1. EPA regulations require that a home be kept in “closed home” conditions for the 12 hours prior to the start of the test.
2. “Closed home” conditions must be maintained for the duration of the test.
3. The EPA recommends that testing devices be placed in the lowest level of a home, whether it is finished or unfinished.
4. The length of a radon test must be at least 48 hours.
5. “Closed home” conditions mean that normal entry and exiting is okay, but windows and doors should not be left open.
6. Regular use of air conditioning and heating during the radon test period is also okay.
7. Fans should not be used around the radon testing equipment.
8. Failure to maintain “closed home” conditions may skew the results negatively or positively.
9. If the radon technician finds that a home has not been closed, a delay may occur and the test may need to be restarted.
10. Continuous electronic radon monitors need to remain plugged into the wall outlet and undisturbed for the length of the test.
11. The radon testing technician will need access to the home to set up and pick up the radon machine.
12. If a home has a radon mitigation system installed, it should remain operational and running in its typical setting during the testing period.

What constitutes a pass or fail on a radon test?

The EPA recommends radon mitigation in homes if the radon level is 4 picocuries per liter (pCi/L) or higher. Radon levels less than 4 pCi/L can still pose a risk and, in many cases, can also be reduced by mitigation.

Is radon an issue in Oregon?

Oregon.gov outlines radon risk levels by zip code. There are some areas that are more prone to higher radon levels than others. A PDF of risk by zip code can be found here and a map of Oregon with radon risk levels can be viewed here. Not all properties in zip codes prone to high levels will have radon issues. Testing is always recommended to verify levels in any property.

For more information on radon, the risk, importance of testing and to get more information on remedies, click here. This workbook has been published by the EPA.