St. Martin Parish, LA Radon Zone Data

St. Martin Parish, LA: EPA's radon zone, explained

EPA's own radon map rates St. Martin Parish zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally that's the 22nd percentile for radon potential — St. Martin Parish outranks 22% of every county EPA has rated.

Where St. Martin Parish sits nationally

St. Martin Parish, Louisiana is home to about 51,218 people across 737.549 square miles. Averaged across its land area, St. Martin Parish runs about 69 people per square mile. By population, St. Martin Parish is the 337th largest of every county sharing its EPA zone — the 67th percentile by population within that zone. Geologically, St. Martin Parish is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

What this actually means for a house in St. Martin Parish

St. Martin Parish's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like St. Martin Parish testing above the action level often enough that skipping a test isn't the safe assumption.

Next steps for a home in St. Martin Parish

For a St. Martin Parish 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 Louisiana's state radon program

For St. Martin Parish, an ongoing number beats a one-time test - a Airthings radon monitor tracks St. Martin Parish'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 St. Martin Parish's figures come from

St. Martin Parish'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.