Is Ouachita Parish, LA a radon risk area?

EPA places Ouachita 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. Ouachita Parish sits at the 28th percentile nationally for radon potential — above 28 of every 100 rated counties.

Ouachita Parish by the numbers

About 157,874 people live in Ouachita Parish, Louisiana, spread over 610.145 square miles. Averaged across its land area, Ouachita Parish runs about 259 people per square mile. Rank 162 by population within its EPA zone puts Ouachita Parish at the 84th percentile among zone peers. EPA's geology-based Region 6 groups Ouachita Parish with 502 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Ouachita Parish

A Zone 3 county like Ouachita Parish is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. Even at Zone 3, Ouachita Parish homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

Next steps for a home in Ouachita Parish

Nothing about Ouachita Parish's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find Louisiana's state radon program

Ouachita Parish's test kit answers today; a Airthings radon monitor keeps answering for Ouachita Parish over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

More on how this number was built

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.