Is Orange County, TX a radon risk area?

Orange County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Nationally that's the 25th percentile for radon potential — Orange County outranks 25% of every county EPA has rated.

Where Orange County sits nationally

About 86,115 people live in Orange County, Texas, spread over 333.799 square miles. Population density there runs about 258 people per square mile. Rank 239 by population within its EPA zone puts Orange County at the 77th percentile among zone peers. Geologically, Orange County is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

Zone vs. an actual test

A Zone 3 county like Orange County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. A Zone 3 rating means Orange County's county-wide average is predicted low, but EPA is explicit that a meaningful share of homes in low-potential zones still test above the action level — a low zone is not a reason to skip testing.

Next steps for a home in Orange County

Nothing about Orange 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

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