Is Hardin County, KY a radon risk area?

Hardin 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. That puts Hardin County in the 60th percentile nationally for radon potential — higher than 60% of the counties EPA has rated.

Where Hardin County sits nationally

About 112,826 people live in Hardin County, Kentucky, spread over 623.909 square miles. That works out to roughly 181 people per square mile. Rank 179 by population within its EPA zone puts Hardin County at the 83rd percentile among zone peers. Geologically, Hardin County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

Hardin 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. Hardin County's Zone 2 rating sits in the middle nationally; EPA's guidance is unchanged by that — test every home regardless of its zone.

If Hardin County tests above the action level

Nothing about Hardin 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 Kentucky's state radon program

Hardin County's test kit answers today; a Airthings radon monitor keeps answering for Hardin 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

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.