Is Houghton County, MI a radon risk area?

EPA places Houghton County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Houghton County sits at the 53rd percentile nationally for radon potential — above 53 of every 100 rated counties.

Where Houghton County sits nationally

About 38,041 people live in Houghton County, Michigan, spread over 1,009.103 square miles. Population density there runs about 38 people per square mile. Rank 414 by population within its EPA zone puts Houghton County at the 60th percentile among zone peers. Houghton County falls in EPA Radon Region 5, one of 524 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Houghton County's predicted average falls between EPA's 4 pCi/L action level and the national indoor average of about 1.3 pCi/L (outdoor air runs roughly 0.4 pCi/L). A county-wide moderate average, like Houghton County's, can still hide a specific house well above or below it — testing is what actually answers the question.

Next steps for a home in Houghton County

Nothing about Houghton County's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find Michigan's state radon program

Houghton County's test kit answers today; a Airthings radon monitor keeps answering for Houghton County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

More on how this number was built

Houghton County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Houghton County carries, the zone explainer covers what it does and doesn't tell you about any one house.