Developments in State Policy
Michigan legislation requires the state to promulgate a building code that incorporates the international codes and that is applicable throughout the state. See Mich. Comp. Laws Ann. 125.1504. The state Department of Licensing and Regulatory Affairs has incorporated the International Residential Code, including Appendix F (radon control), into the 2009 Michigan Residential Code. Nine Michigan counties are designated as Zone 1 counties (based on the EPA Map of Radon Zones) subject to the radon control requirements in Appendix F.