What EPA's radon map says about Sevier County

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

How Sevier County compares

About 100,184 people live in Sevier County, Tennessee, spread over 592.518 square miles. Population density there runs about 169 people per square mile. Among counties sharing Sevier County's EPA zone, it outranks 81% of them by population. Geologically, Sevier County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

Sevier County's predicted average falls between EPA's 4 pCi/L action level and the national indoor average of about 1.3 pCi/L (outdoor air runs roughly 0.4 pCi/L). Middle-of-the-pack doesn't mean risk-free for any one Sevier County address — a moderate county average still leaves individual homes to test either side of it.

Next steps for a home in Sevier County

Mitigation cost doesn't depend on Sevier 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 Tennessee's state radon program

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

Sevier County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.