La Salle County, TX: EPA's radon zone, explained

La Salle County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Nationally, La Salle County ranks higher in radon potential than 4% of rated counties (the 4th percentile).

La Salle County by the numbers

La Salle County, Texas is home to about 6,679 people across 1,486.704 square miles. Population density there runs about 4 people per square mile. By population, La Salle County is the 911th largest of every county sharing its EPA zone — the 12th percentile by population within that zone. Geologically, La Salle County is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

Zone vs. an actual test

La Salle County's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. Don't read Zone 3 as a pass for La Salle County — EPA's guidance to test every home makes no exception for counties predicted low.

Testing and mitigation in La Salle County

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

The methodology guide shows exactly which EPA and Census sources feed La Salle County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.