Armstrong County, TX radon potential

Armstrong County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Armstrong County sits at the 34th percentile nationally for radon potential — above 34 of every 100 rated counties.

Where Armstrong County sits nationally

Armstrong County, Texas is home to about 1,809 people across 909.124 square miles. That works out to roughly 2 people per square mile. Within its own EPA zone, Armstrong County is bigger by population than 2% of the counties that share it. Geologically, Armstrong County is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

Zone vs. an actual test

Armstrong County's predicted average falls between EPA's 4 pCi/L action level and the national indoor average of about 1.3 pCi/L (outdoor air runs roughly 0.4 pCi/L). A county-wide moderate average, like Armstrong County's, can still hide a specific house well above or below it — testing is what actually answers the question.

Next steps for a home in Armstrong County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Texas's state radon program

For Armstrong County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Armstrong 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 Armstrong County's figures come from

Armstrong County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Armstrong County carries, the zone explainer covers what it does and doesn't tell you about any one house.