What EPA's radon map says about Webster County

EPA's own radon map rates Webster County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Webster County sits at the 42nd percentile nationally for radon potential — above 42 of every 100 rated counties.

How Webster County compares

About 12,854 people live in Webster County, Kentucky, spread over 332.027 square miles. That works out to roughly 39 people per square mile. Among counties sharing Webster County's EPA zone, it outranks 26% of them by population. EPA's geology-based Region 4 groups Webster County with 735 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Webster 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. Webster 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 Webster County tests above the action level

Mitigation cost doesn't depend on Webster County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Kentucky's state radon program

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

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.