Lafayette Parish, LA radon potential

EPA's own radon map rates Lafayette Parish zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Rank it against the rest of the country and Lafayette Parish lands in the 30th percentile for radon potential.

Lafayette Parish by the numbers

Lafayette Parish, Louisiana is home to about 254,241 people across 268.833 square miles. Averaged across its land area, Lafayette Parish runs about 946 people per square mile. Within its own EPA zone, Lafayette Parish is bigger by population than 90% of the counties that share it. Lafayette Parish falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Lafayette Parish's Zone 3 prediction undercuts the roughly 1.3 pCi/L most US homes average, nowhere near EPA's 4 pCi/L threshold for recommending mitigation. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Lafayette Parish testing above the action level often enough that skipping a test isn't the safe assumption.

Testing and mitigation in Lafayette Parish

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 Louisiana's state radon program

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

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