What EPA's radon map says about Monroe County

EPA's own radon map rates Monroe County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally, Monroe County ranks higher in radon potential than 19% of rated counties (the 19th percentile).

How Monroe County compares

About 33,483 people live in Monroe County, Mississippi, spread over 765.128 square miles. Averaged across its land area, Monroe County runs about 44 people per square mile. Among counties sharing Monroe County's EPA zone, it outranks 57% of them by population. Geologically, Monroe County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

Monroe County's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. Don't read Zone 3 as a pass for Monroe County — EPA's guidance to test every home makes no exception for counties predicted low.

If Monroe County tests above the action level

Mitigation cost doesn't depend on Monroe 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

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

More on how this number was built

The methodology guide shows exactly which EPA and Census sources feed Monroe County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.