What EPA's radon map says about Coahoma County

EPA's own radon map rates Coahoma County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally that's the 13th percentile for radon potential — Coahoma County outranks 13% of every county EPA has rated.

How Coahoma County compares

About 20,105 people live in Coahoma County, Mississippi, spread over 553.102 square miles. Population density there runs about 36 people per square mile. Among counties sharing Coahoma County's EPA zone, it outranks 40% of them by population. EPA's geology-based Region 4 groups Coahoma County with 735 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Coahoma County

At Zone 3, Coahoma County's predicted county average is under the national indoor average (~1.3 pCi/L) and well below EPA's 4 pCi/L action level — outdoor air nationally runs about 0.4 pCi/L for comparison. Even at Zone 3, Coahoma County homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

If Coahoma County tests above the action level

Mitigation cost doesn't depend on Coahoma County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Mississippi's state radon program

Coahoma County's test kit answers today; a Airthings radon monitor keeps answering for Coahoma County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 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.