Houston County, AL: EPA's radon zone, explained

EPA places Houston 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. That puts Houston County in the 26th percentile nationally for radon potential — higher than 26% of the counties EPA has rated.

Where Houston County sits nationally

Houston County, Alabama is home to about 109,366 people across 579.828 square miles. Averaged across its land area, Houston County runs about 189 people per square mile. By population, Houston County is the 208th largest of every county sharing its EPA zone — the 80th percentile by population within that zone. Geologically, Houston County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

A Zone 3 county like Houston County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. Don't read Zone 3 as a pass for Houston County — EPA's guidance to test every home makes no exception for counties predicted low.

Testing and mitigation in Houston County

For a Houston 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 Alabama's state radon program

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

Where Houston County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Houston County's numbers. Whatever zone Houston County carries, the zone explainer covers what it does and doesn't tell you about any one house.