Irwin County, GA: EPA's radon zone, explained

Irwin County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Nationally, Irwin County ranks higher in radon potential than 6% of rated counties (the 6th percentile).

Where Irwin County sits nationally

Irwin County, Georgia is home to about 9,155 people across 354.363 square miles. That works out to roughly 26 people per square mile. By population, Irwin County is the 846th largest of every county sharing its EPA zone — the 18th percentile by population within that zone. Irwin County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Irwin County

Irwin 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 Irwin County testing above the action level often enough that skipping a test isn't the safe assumption.

If Irwin County tests above the action level

For a Irwin 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 Georgia's state radon program

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

Irwin County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.