Is Henderson County, TN a radon risk area?

EPA places Henderson County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. That puts Henderson County in the 50th percentile nationally for radon potential — higher than 50% of the counties EPA has rated.

Henderson County by the numbers

About 28,183 people live in Henderson County, Tennessee, spread over 520.009 square miles. That works out to roughly 54 people per square mile. Rank 505 by population within its EPA zone puts Henderson County at the 51st percentile among zone peers. Henderson County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

EPA's Zone 2 rating for Henderson County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Nothing about a Zone 2 label lowers the case for testing in Henderson County — EPA recommends it in every zone, moderate included.

If Henderson County tests above the action level

Nothing about Henderson 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

Henderson County's test kit answers today; a Airthings radon monitor keeps answering for Henderson 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. Whatever zone Henderson County carries, the zone explainer covers what it does and doesn't tell you about any one house.