Is Hardin County, TX a radon risk area?

EPA's own radon map rates Hardin County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally, Hardin County ranks higher in radon potential than 23% of rated counties (the 23rd percentile).

Hardin County by the numbers

About 58,670 people live in Hardin County, Texas, spread over 890.578 square miles. That works out to roughly 66 people per square mile. Rank 308 by population within its EPA zone puts Hardin County at the 70th percentile among zone peers. EPA's geology-based Region 6 groups Hardin County with 502 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Hardin County

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Hardin County's Zone 3 prediction is the low end of the scale. Even at Zone 3, Hardin County homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

Next steps for a home in Hardin County

Nothing about Hardin 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

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

The methodology guide shows exactly which EPA and Census sources feed Hardin County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.