Walthall County, MS radon potential

Walthall County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Walthall County sits at the 9th percentile nationally for radon potential — above 9 of every 100 rated counties.

Where Walthall County sits nationally

Walthall County, Mississippi is home to about 13,839 people across 403.928 square miles. Population density there runs about 34 people per square mile. Within its own EPA zone, Walthall County is bigger by population than 29% of the counties that share it. Geologically, Walthall County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

Zone vs. an actual test

Walthall County'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. A Zone 3 label describes Walthall County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Testing and mitigation in Walthall County

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 Mississippi's state radon program

For Walthall County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Walthall County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

Where Walthall County's figures come from

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