Linn County, KS: EPA's radon zone, explained

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. Rank it against the rest of the country and Linn County lands in the 40th percentile for radon potential.

How Linn County compares

Linn County, Kansas is home to about 9,841 people across 594.081 square miles. Averaged across its land area, Linn County runs about 17 people per square mile. By population, Linn County is the 821st largest of every county sharing its EPA zone — the 20th percentile by population within that zone. Geologically, Linn County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

Zone vs. an actual test

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Linn County's Zone 2 prediction lands in the gap between the two. Middle-of-the-pack doesn't mean risk-free for any one Linn County address — a moderate county average still leaves individual homes to test either side of it.

If Linn County tests above the action level

For a Linn County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Kansas'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. Code RADONZONE-10OFF takes 10% off at checkout.

Where Linn County's figures come from

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