Is Blount County, TN a radon risk area?

Blount County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Rank it against the rest of the country and Blount County lands in the 95th percentile for radon potential.

Blount County by the numbers

About 142,211 people live in Blount County, Tennessee, spread over 558.844 square miles. Population density there runs about 254 people per square mile. Rank 142 by population within its EPA zone puts Blount County at the 87th percentile among zone peers. Blount County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

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 Blount County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. Being in Zone 1 raises the odds Blount County homes test above the action level, but it does not mean any specific house does — EPA recommends every home be tested, in every zone, because the only way to know is to test.

Testing and mitigation in Blount County

Nothing about Blount 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

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

The methodology guide shows exactly which EPA and Census sources feed Blount County's numbers. Whatever zone Blount County carries, the zone explainer covers what it does and doesn't tell you about any one house.