Lafayette County, MS: EPA's radon zone, explained

EPA places Lafayette County 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. Rank it against the rest of the country and Lafayette County lands in the 23rd percentile for radon potential.

Where Lafayette County sits nationally

Lafayette County, Mississippi is home to about 59,843 people across 631.697 square miles. Population density there runs about 95 people per square mile. By population, Lafayette County is the 302nd largest of every county sharing its EPA zone — the 71st percentile by population within that zone. EPA's geology-based Region 4 groups Lafayette County with 735 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

A Zone 3 county like Lafayette County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. Even at Zone 3, Lafayette County 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 Lafayette County

For a Lafayette 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 Mississippi's state radon program

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

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