Linn County, MO radon potential

Linn County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Linn County sits at the 41st percentile nationally for radon potential — above 41 of every 100 rated counties.

How Linn County compares

Linn County, Missouri is home to about 11,910 people across 615.588 square miles. That works out to roughly 19 people per square mile. Within its own EPA zone, Linn County is bigger by population than 24% of the counties that share it. Linn County falls in EPA Radon Region 7, one of 412 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Linn County

Linn County's Zone 2 prediction clears the 1.3 pCi/L national indoor average without reaching EPA's own 4 pCi/L point for recommending a fix. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Linn County — testing is the only way to know an individual home's actual level.

If Linn County tests above the action level

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 Missouri's state radon program

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

Where Linn County's figures come from

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