Ascension Parish, LA radon potential

EPA places Ascension Parish 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. That puts Ascension Parish in the 27th percentile nationally for radon potential — higher than 27% of the counties EPA has rated.

Ascension Parish by the numbers

Ascension Parish, Louisiana is home to about 133,534 people across 290.003 square miles. Averaged across its land area, Ascension Parish runs about 460 people per square mile. Within its own EPA zone, Ascension Parish is bigger by population than 83% of the counties that share it. Ascension Parish falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Ascension 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. Even at Zone 3, Ascension Parish homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

Testing and mitigation in Ascension 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 Ascension Parish, an ongoing number beats a one-time test - a Airthings radon monitor tracks Ascension Parish's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

Where Ascension Parish's figures come from

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. Whatever zone Ascension Parish carries, the zone explainer covers what it does and doesn't tell you about any one house.