Michigan has significant radon risk across much of the state, with an estimated 30–35% of Michigan homes testing above the EPA action level of 4.0 pCi/L. The Michigan Department of Environment, Great Lakes, and Energy (EGLE) estimates that radon may contribute to hundreds of lung cancer deaths in Michigan annually. Michigan’s geology — including granitic basement rock in the Upper Peninsula, glacial till and outwash across both peninsulas, and limestone formations in the Lower Peninsula — creates varied but often significant radon potential.
EPA Radon Zone Designation
Michigan is predominantly EPA Radon Zone 1. Michigan counties range from Zone 1 in parts of the Upper Peninsula and northern Lower Peninsula to Zone 2 in much of the southern Lower Peninsula. The Upper Peninsula counties overlying granitic basement rock tend to have higher radon potential. Northern Lower Peninsula counties in the glaciated sand and gravel deposits also show elevated levels.
Radon Contractor Licensing in Michigan
Michigan requires radon contractors to hold current NRPP or NRSB national certification. Michigan’s radon program is administered through the Michigan Department of Environment, Great Lakes, and Energy (EGLE). Michigan does not have a separate state radon contractor licensing statute — national certification through NRPP or NRSB is the operative requirement. EGLE maintains resources on radon and certified professionals. Verify contractor credentials at nrpp.info or nrsb.org before hiring.
Radon Disclosure Requirements in Michigan
Michigan’s real estate disclosure law requires sellers to complete a Seller’s Disclosure Statement disclosing known defects and conditions. The Michigan disclosure form includes questions about radon — specifically whether the property has been tested and what the results were, and whether a radon mitigation system is installed. Sellers must disclose known radon test results. Radon testing is standard practice in Michigan real estate transactions, particularly in northern Michigan and Upper Peninsula properties.
Radon-Resistant New Construction (RRNC) in Michigan
Michigan does not have a statewide RRNC mandate for new residential construction. The Michigan Building Code does not require RRNC features statewide. EGLE recommends RRNC for new construction in Zone 1 areas. The IRC Appendix F provisions are available for local adoption. Some Michigan municipalities have incorporated RRNC requirements locally. Buyers of new construction should ask builders about RRNC, particularly in northern Michigan and Upper Peninsula locations.
Highest-Radon Counties and Areas in Michigan
Michigan’s highest-radon areas include Upper Peninsula counties overlying granitic and iron-bearing bedrock: Marquette, Iron, Baraga, Houghton, Keweenaw, and Ontonagon counties. Northern Lower Peninsula counties with glacial sand and gravel deposits — including Kalkaska, Crawford, Roscommon, and Ogemaw counties — also show elevated levels. The EGLE publishes county-level radon data from testing surveys conducted across the state.
Testing Resources for Michigan Residents
The Michigan Department of Environment, Great Lakes, and Energy (EGLE) administers the state radon program and provides resources for homeowners including lists of certified contractors, low-cost or free test kit programs (availability varies by year and funding), and technical guidance on radon mitigation. Contact the state radon program directly for the most current contractor list, any available test kit distribution programs, and jurisdiction-specific requirements that may have changed since this page was last updated.
Frequently Asked Questions
Does Michigan require radon disclosure in real estate?
Yes. The Michigan Seller’s Disclosure Statement requires sellers to disclose known radon test results and the presence of any mitigation system. Sellers with knowledge of elevated radon levels must include this in their disclosure.
What parts of Michigan have the highest radon?
Upper Peninsula counties overlying granitic bedrock — particularly Marquette, Iron, Baraga, Houghton, and Keweenaw counties — have the highest radon potential. Northern Lower Peninsula counties with glacial sand and gravel also show elevated levels.
Does Michigan require radon contractor certification?
NRPP or NRSB national certification is required. No separate Michigan-specific licensing statute exists. Verify credentials at nrpp.info or nrsb.org before hiring any radon contractor.
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