Is Sherman County, TX a radon risk area?

EPA's own radon map rates Sherman County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Nationally that's the 34th percentile for radon potential — Sherman County outranks 34% of every county EPA has rated.

Sherman County by the numbers

About 2,771 people live in Sherman County, Texas, spread over 922.86 square miles. Population density there runs about 3 people per square mile. Rank 988 by population within its EPA zone puts Sherman County at the 4th percentile among zone peers. Sherman County falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Sherman 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). A county-wide moderate average, like Sherman County's, can still hide a specific house well above or below it — testing is what actually answers the question.

Next steps for a home in Sherman County

Nothing about Sherman 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 Texas's state radon program

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