What EPA's radon map says about Terry County

EPA's own radon map rates Terry County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally, Terry County ranks higher in radon potential than 8% of rated counties (the 8th percentile).

How Terry County compares

About 11,602 people live in Terry County, Texas, spread over 888.852 square miles. Population density there runs about 13 people per square mile. Among counties sharing Terry County's EPA zone, it outranks 24% of them by population. Terry County falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

At Zone 3, Terry County's predicted county average is under the national indoor average (~1.3 pCi/L) and well below EPA's 4 pCi/L action level — outdoor air nationally runs about 0.4 pCi/L for comparison. A Zone 3 label describes Terry County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Next steps for a home in Terry County

Mitigation cost doesn't depend on Terry County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Texas's state radon program

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