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

EPA places Liberty 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. Rank it against the rest of the country and Liberty County lands in the 27th percentile for radon potential.

Liberty County by the numbers

Liberty County, Texas is home to about 115,042 people across 1,158.482 square miles. Population density there runs about 99 people per square mile. By population, Liberty County is the 201st largest of every county sharing its EPA zone — the 81st percentile by population within that zone. EPA's geology-based Region 6 groups Liberty County with 502 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Liberty County

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Liberty County's Zone 3 prediction is the low end of the scale. A Zone 3 rating means Liberty 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.

Testing and mitigation in Liberty County

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

Where Liberty County's figures come from

Liberty County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.