Brazos County, TX: EPA's radon zone, explained

Brazos County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Nationally, Brazos County ranks higher in radon potential than 30% of rated counties (the 30th percentile).

Where Brazos County sits nationally

Brazos County, Texas is home to about 249,624 people across 586.15 square miles. That works out to roughly 426 people per square mile. By population, Brazos County is the 105th largest of every county sharing its EPA zone — the 90th percentile by population within that zone. Brazos County falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

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

Testing and mitigation in Brazos County

For a Brazos County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Texas's state radon program

For Brazos County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Brazos County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

Where Brazos County's figures come from

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.