Is Wilson County, TN a radon risk area?

EPA's own radon map rates Wilson County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Nationally that's the 96th percentile for radon potential — Wilson County outranks 96% of every county EPA has rated.

Where Wilson County sits nationally

About 169,948 people live in Wilson County, Tennessee, spread over 571.088 square miles. Averaged across its land area, Wilson County runs about 298 people per square mile. Rank 113 by population within its EPA zone puts Wilson County at the 89th percentile among zone peers. EPA's geology-based Region 4 groups Wilson County with 735 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Wilson County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. EPA's guidance doesn't change because of a Zone 1 label: test the house. What changes is the reason to not put it off in Wilson County specifically.

If Wilson County tests above the action level

Nothing about Wilson 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

Wilson County's test kit answers today; a Airthings radon monitor keeps answering for Wilson County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

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.