Fillmore County, MN radon potential

EPA's own radon map rates Fillmore County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Rank it against the rest of the country and Fillmore County lands in the 82nd percentile for radon potential.

Fillmore County by the numbers

Fillmore County, Minnesota is home to about 21,502 people across 861.333 square miles. That works out to roughly 25 people per square mile. Within its own EPA zone, Fillmore County is bigger by population than 48% of the counties that share it. EPA's geology-based Region 5 groups Fillmore County with 523 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Fillmore County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. That doesn't mean every Fillmore 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.

Testing and mitigation in Fillmore County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Minnesota's state radon program

For Fillmore County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Fillmore County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

Where Fillmore County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Fillmore County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.