Is Norman County, MN a radon risk area?

EPA's own radon map rates Norman County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Nationally, Norman County ranks higher in radon potential than 72% of rated counties (the 72nd percentile).

How Norman County compares

About 6,284 people live in Norman County, Minnesota, spread over 872.789 square miles. That works out to roughly 7 people per square mile. Rank 872 by population within its EPA zone puts Norman County at the 18th percentile among zone peers. EPA's geology-based Region 5 groups Norman County with 523 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Norman County

Where the national indoor average runs about 1.3 pCi/L, Norman County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. That doesn't mean every Norman County house tests high — a zone is a county-wide prediction, never a single-home reading — but it's a reason to test sooner rather than let it wait.

Next steps for a home in Norman County

Nothing about Norman 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 Minnesota's state radon program

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

More on how this number was built

The methodology guide shows exactly which EPA and Census sources feed Norman County's numbers. Whatever zone Norman County carries, the zone explainer covers what it does and doesn't tell you about any one house.