What EPA's radon map says about Henderson County

EPA places Henderson County in Zone 3 - Low Potential — a predicted county-wide average indoor radon level below 2 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 25th percentile for radon potential — Henderson County outranks 25% of every county EPA has rated.

Where Henderson County sits nationally

About 87,467 people live in Henderson County, Texas, spread over 873.788 square miles. That works out to roughly 100 people per square mile. Among counties sharing Henderson County's EPA zone, it outranks 77% of them by population. EPA's geology-based Region 6 groups Henderson County with 502 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Henderson County's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. A Zone 3 label describes Henderson 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 Henderson County

Mitigation cost doesn't depend on Henderson 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

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. RADONZONE-10OFF at checkout knocks 10% off.

More on how this number was built

The methodology guide shows exactly which EPA and Census sources feed Henderson County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.