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Testing and Mitigation

The State advises you to take action to reduce the radon level in your home's indoor air at 4 pCi/L, but consider reducing levels between 2 and 4 pCi/L. The current advisory level for radon in your home's water supply is 4,000 pCi/L. At levels of 4,000 pCi/L or higher you should consider action beginning with reviewing your total radon risk (from radon in air and water). As your radon level in water gets closer to 10,000 pCi/L, you need to more strongly consider installing treatment. Under Maine law, only the owner or occupant of a residence or someone registered with the state to provide these services, may test for radon, install and/or advise on the installation of a radon reduction (mitigation) system. If the home or residence is for sale then the owner or occupant cannot test for radon or install a system to reduce it, the testing and mitigation of properties for sale must be done by a registered radon service provider.

What everyone should know about testing your home for radiation.: Real estate transactions and health concerns often trigger testing of drinking water for many contaminants. Testing for radioactive elements is often overlooked when considering the numerous tests available, yet radioactive elements can exist at unsafe levels in both the air in the home and in drinking water from drilled wells.
Radon is a radioactive gas that is formed from naturally occurring elements in the rocks and soil. It can filter through the soil and enter the basement of the home. It can also dissolve in groundwater and escape into the air as you use the water. Radium and uranium, the naturally occurring elements that produce radon, can also dissolve in well water. These elements emit a type of radiation known as alpha radiation. Some people who drink water or breathe air with high levels of alpha emitters over many years may have an increased risk of getting cancer and other health problems.
Radon and other alpha emitters can be detected through laboratory tests. These test kits are available at the Maine Health and Environmental Testing Laboratory or other private laboratories. A list of radon testing laboratories can be obtained from the Radiation Control Program at the DHS Division of Health Engineering.

What Tests Should I Do?

Short Term Radon Air Test: This test is recommended for all homes. It measures radon present in the air in the home but does not tell by what pathway it entered the home. The exposure period for the HETL device is exactly 48 hours. The lab must receive the sample no later than 4 days after the end of the exposure period. Your results will be mailed approximately within 1 week after the lab receives your sample.
Radon Water Test: This test is recommended for drilled wells and tests only for radon present in the water. It requires a special small vial to obtain the water sample and must be returned promptly to the lab for analysis. Your results will be mailed approximately within 1 week after the lab receives your sample.
Gross Alpha Test: This test detects the presence of any elements in the water that emit alpha radiation except radon and is recommended for drilled wells. It requires about one-half gallon of water to process. This test does not indicate what specific element is present but only checks for any alpha emitters. Therefore, in some cases, more specific follow-up tests need to be done to determine whether a result is satisfactory or whether treatment is recommended. HETL is currently the only laboratory in Maine certified by EPA to do this test. Your results will be mailed within approximately 3 weeks after the lab receives your sample.
Uranium Test: This test also might be recommended in some cases as a follow up to a high gross alpha test. It measures only the element uranium that might be present and requires a 120mL sample. Your results will be mailed approximately within 2 weeks after the lab receives your sample.

Radon Test FAQ

How do I know if my radon levels are too high?: The Maine Radiation Control Program provides the following guidance, “The State advises you to take action to reduce the radon level in your home's indoor air at 4 pCi/L, but consider reducing levels between 2 and 4 pCi/L. The current advisory level for radon in your home's water supply is 4,000 pCi/L. At levels of 4,000 pCi/L or higher you should consider action beginning with reviewing your total radon risk (from radon in air and water). As your radon level in water gets closer to 10,000 pCi/L, you need to more strongly consider installing treatment.”
I received a high radon result. What is next?: It can be beneficial to verify a result with a second test, especially if your result is close to the action level of 4.0 pCi/L for air or 4,000 pCi/L for water. The Maine Radiation Control Program is an excellent resource for discussion of mitigation options and has a search engine for licensed Radon professionals in your area. The Maine RCP can be reached by calling 207-287-5676 or online at Department of Health and Human Services. Long term radon testing may be appropriate for tests near 4.0 pCi/L and can be purchased from private laboratories, such as Radonova (Radonova.com).
How often should I test my house for radiation?: The Maine Radiation Control Program has put out guidelines for routine radon monitoring, found here. For homes with no history of high Radon, testing every 3-5 years or after any significant home renovation or event that disturbs the surrounding soil and bedrock is recommended. Homes with radon mitigation systems should be tested every 2 years to ensure the mitigation system is working as intended.
How do I conduct my radon in air test?: The Maine Radiation Control Program provides the following tipsheet on conducting a radon air test. See Test Your Home for Radon (PDF). If you have any questions and would like to talk to a radiochemist, please contact the Radiochemistry Department at 207-287-1714 or 207-287-1732.