Washtenaw County enforces Appendix F of the 2003 Michigan Residential Code (PDF). This appendix requires residential construction projects to be built using methods that limit the entry of radon gas into the structure.
Radon in Washtenaw County
Radon is a tasteless, colorless, odorless gas that can seep into homes through cracks in the foundation, sump pump crocks, hollow block walls, or other openings. Long-term exposure to radon is the second-leading cause of lung cancer in the United States. Washtenaw County has been designated a "Zone 1 County," meaning homes built here have the highest potential for elevated radon levels due to the County's geology and soil composition.
Appendix F requirements have been shown to help lower indoor radon levels, protecting the public from exposure to this potentially deadly gas.