General Radon Information

Kentucky specific radon and radon level information can be found throughout this site. You will be able to find information about certified radon inspectors in Kentucky, as well as detailed radon level information for every county in Kentucky.

Radon comes from the natural radioactive decay of radium and uranium found in the soil beneath the house. The amount of radon in the soil depends on soil chemistry, which varies from one house to the next. Radon levels in the soil range from a few hundred to several thousands of pCi/L. The amount of radon that escapes from the soil to enter the house depends on the weather, soil porosity, soil moisture, and the suction within the house.

For a more scientific definition: Radon is a colorless, chemically unreactive inert gas, it is the densest gas known. The gas and its highly radioactive (radioactivity described) metallic daughter products emit alpha and beta particles and gamma rays. It has been used in the treatment of cancer by radiotherapy. In homes and other buildings, in some areas of the world, radon produced by the radioactive decay of uranium-238 present in soil and rock can reach levels regarded as dangerous. (Chemical Symbol/Element Number: Rn222)

Two standard methods exist for testing a home for the presence of radon gas. Short-term testing methods are designed to provide a quick radon value. Short-term tests can be as short as 48 hours and as long as 90 days. Long-term testing methods are designed to provide an annual average of radon gas. Long-term tests run for a minimum of 90 days, and usually for 6 to 12 months. The EPA recommends performing a short-term test for radon. If that test comes back below the EPA Action Level ( 4.0 pCi/L), then no further immediate action is warranted. However, the home should be tested again after any air sealing work, heating/air conditioning system changes or foundation modifications. If the short-term test returns with a radon value of 4.0-10.0 pCi/L, the EPA recommends performing a long-term test to gauge the home's annual radon concentration. The results of the long-term test should be used to determine the necessity of radon mitigation (reduction). Another option is to conduct a second short term test if quicker results are desired. If the first short-term test returns above 10.0 pCi/L, then the EPA recommends performing a second short-term test to verify the results and using the average of the two short-term tests to determine the necessity of radon mitigation.

The USEPA action level for radon is 4.0 picocuries per liter of air (pCi/L). (pCi/l= picocuries per liter, the most popular method of reporting radon levels. For those interested in the numbers, a picoCurie is 0.000,000,000,001 (one-trillionth) of a Curie, an international measurement unit of radioactivity. One pCi/l means that in one liter of air there will be 2.2 radioactive disintegrations each minute. For example, at 4 pCi/l there will be approximately 12,672 radioactive disintegrations in one liter of air, during a 24-hour period.) The risk of developing lung cancer at 4.0 pCi/L is estimated at about 7 lung cancer deaths per 1000 persons. That is why USEPA and IEMA recommends reducing your radon level if the concentration is 4.0 pCi/L or more. Lung cancer in humans arising from radon exposure is recognized by the following health and environmental organizations:

* American Medical Association

* U.S. Surgeon General

* U.S. Department of Health and Human Services

* U.S. Public Health Service

* U.S. Environmental Protection Agency

* Center for Disease Control

* National Academy of Science

* National Cancer Institute

* World Health Organization

The Kentucky Radon Program is involved in educational and awareness programs for citizens throughout the commonwealth, including exhibits and staff presentations, responding to phone and e-mail inquiries and distributing radon awareness literature.

The program also acts as liaison between the U.S. Environmental Protection Agency, county and district health departments and universities, which receive mini-grants through the program.

Information about the Kentucky Radon Program can be found at their website ( or at the address below:

Kentucky Radon Program

275 East Main Street

Frankfort, KY 40621

(502) 564-4856