Is Perry County, TN a radon risk area?

EPA's own radon map rates Perry County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Perry County sits at the 75th percentile nationally for radon potential — above 75 of every 100 rated counties.

Perry County by the numbers

About 8,987 people live in Perry County, Tennessee, spread over 414.765 square miles. That works out to roughly 22 people per square mile. Rank 796 by population within its EPA zone puts Perry County at the 25th percentile among zone peers. EPA's geology-based Region 4 groups Perry County with 735 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Perry County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Perry County will test well under the action level, and EPA's guidance is to test regardless of zone.

Testing and mitigation in Perry County

Nothing about Perry 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 Tennessee's state radon program

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

Perry County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.