Lauderdale County, MS: EPA's radon zone, explained
EPA places Lauderdale 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. That puts Lauderdale County in the 24th percentile nationally for radon potential — higher than 24% of the counties EPA has rated.
Lauderdale County by the numbers
Lauderdale County, Mississippi is home to about 70,588 people across 703.676 square miles. That works out to roughly 100 people per square mile. By population, Lauderdale County is the 268th largest of every county sharing its EPA zone — the 74th percentile by population within that zone. Lauderdale County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.
Zone vs. an actual test
Lauderdale 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. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Lauderdale County testing above the action level often enough that skipping a test isn't the safe assumption.
If Lauderdale County tests above the action level
For a Lauderdale 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 Lauderdale County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Lauderdale 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 Lauderdale County's figures come from
The methodology guide shows exactly which EPA and Census sources feed Lauderdale County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.