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Michigan Indoor Radon Program Overview


The Michigan Indoor Radon Program is a non-regulatory program.  Its purpose is to increase awareness of the health risk associated with exposure to elevated indoor radon levels, to encourage testing for radon, and to also encourage citizens to take action to reduce their exposure once elevated radon levels are found.  The program resides in the Radiological Protection Section of the Materials Management Division of the Michigan Department of Environment, Great Lakes, and Energy (EGLE).

radon info graphic

Funding from the U.S. Environmental Protection Agency (USEPA), provides for a toll-free radon hotline (800-RADON GAS/800-723-6642) that citizens can call to get information on the health risk, how to test, how to interpret results, how to reduce elevated radon levels, etc.  Literature is distributed free of charge, and program staff can help locate do-it-yourself test kits, professional testers, and radon mitigation contractors.

Radon was first recognized as an indoor environmental health concern in the mid-1980s.  Media coverage at the time was both enlightened and alarming, causing the state agencies to be swamped with calls from people wanting to know more about radon. Residents wanted to know the health effects from radon, how to test for radon, and what could be done to fix things if elevated levels were found. 

In the mid-1980s, the Michigan Department of Public Health (MDPH), now the Department of Health and Human Services, performed a statewide residential indoor air radon survey to better characterize radon health risks across the state.  The survey was performed in the winter of 1987-88 with the assistance of USEPA and local health departments.  Survey data was collected across 79 of Michigan's 83 counties and the results showed that approximately 12 percent of the homes across Michigan had elevated radon levels exceeding the 4 picocuries per liter (pCi/l) of air guideline.  In some counties, as many as 40-45 percent or more of the homes exceeded the established guideline.

In June 1989, the MDPH secured a State Indoor Radon Grant (SIRG) to evaluate radon levels in public schools across Michigan.  The survey was conducted in 1991 measuring radon levels in more than 385 school buildings across Michigan.  While fewer than three percent of the rooms tested showed radon levels greater than the 4 pCi/l, as many as one in four buildings had at least one room with an elevated radon level.

In 1991 to 1992, another SIRG was used to evaluate the extent of the radon problem in the state's one radon hotspot.  The Republic area in Marquette County had been identified as the state's only radon hotspot during the 1987-88 radon survey.  In the Republic area study, both short-term and long-term radon detectors were provided to more than 250 homeowners.  The short-term results indicated that more than 84 percent of the sites in Republic had radon levels greater than 4 pCi/l and more than 45 percent of those had radon levels greater than 20 pCi/l.  Five percent of the sites tested had radon levels exceeding 100 pCi/l and the highest level detected was 389 pCi/l. 

After collecting the statewide survey data, it became clear that residents across the state were all at risk of exposure to elevated levels of radon.  The only way to truly determine the risk to homeowners is to test the home for radon levels.  As a result, the program shifted from surveying statewide radon levels to educating residents about radon and test to determine if radon levels needed to be fixed. Funding was used to provide radon test kits to local health departments in every county across Michigan.  Literature and videotapes were mailed to 670 libraries. Outreach materials were developed and shared with the local health departments during annual radon training.  Training and outreach activities continued and were expanded to include builders and realtors.  A radon mitigation system demonstration project was conducted for residents in the Republic area.  The project demonstration showed residents that radon levels could be reduced, and that mitigation techniques were not too cumbersome or costly.  Mailings were sent to builders and realtors to share new publications with residents.  A direct mailing was sent to households in nine counties with predicted average indoor radon levels greater than 4 pCi/l.  Outreach efforts were extended to worksite wellness coordinators making them aware of available publications and encourage their sharing the information with residents. 

radon graphic encourage the public to test for radon

Many local health departments are becoming more proactive and aggressive in their outreach. Some local health departments are targeting specific areas in order to increase testing in areas with high radon potential.  While future plans include continuing efforts to increase awareness, additional emphasis will be placed on the need to actually test and mitigate if elevated levels are found.  Additional efforts to partner with health care providers in educating residents will also be taken.

In 1993 the USEPA worked with the U.S. Geological Survey and the state radon programs to develop a "map of zones" to help identify areas of the U.S. with the potential for elevated indoor radon levels.  Counties were ranked into one of three categories (Zone 1, Zone 2, or Zone 3, with "1" being higher potential and "3" being lower potential) based on indoor radon measurements (i.e., data from the 1987-88 residential radon survey), geology, aerial radioactivity, soil permeability, and foundation type.  Click here to see the USEPA Map of Radon Zones.

Any home could have a radon problem, whether it's in an area with a high radon potential or an area with a low radon potential, or whether it's old or new, energy-efficient or drafty, built on a slab or built over a basement or crawlspace.  Because it's a tasteless, odorless, colorless gas, there are no physical signs that will alert you to the presence of radon in a home.  (It doesn't smell bad.  There is no discoloration of the foundation.  There are no visible traces of the gas; etc.)  And, there are no warning symptoms to let you know you're being exposed.  (It doesn't cause headaches, nausea, fatigue, skin rashes, etc.)  The only way to know whether your home has a problem--or whether you are at risk--is to test! 

In June of 1989, then Governor James Blanchard designated the MDPH the state agency with primary responsibility for the radon program.  In April 1996, an Executive Order issued by Governor John Engler transferred the responsibility to the Michigan Department of Environmental Quality (subsequently renamed EGLE).

Radon - One in Four Michigan Homes has High levels of Radon

As more test data was accumulated, EGLE has created a new map that shows the percentage of elevated test results by county.  This map is based on over 200,000 homeowner test results.  It shows that one in four homes have elevated radon levels across Michigan, suggesting that radon exposure is a continuing public health concern.

While your neighbor's test results may give you an idea of the potential for a problem in your home, radon levels can vary significantly from lot to lot and home to home. 

Do not rely on your neighbor's test results to determine your risk.  Test your own home and be certain!