Greene County, IN: EPA's radon zone, explained

Greene County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. That puts Greene County in the 51st percentile nationally for radon potential — higher than 51% of the counties EPA has rated.

How Greene County compares

Greene County, Indiana is home to about 31,219 people across 542.469 square miles. Averaged across its land area, Greene County runs about 58 people per square mile. By population, Greene County is the 475th largest of every county sharing its EPA zone — the 54th percentile by population within that zone. Geologically, Greene County is grouped into EPA Region 5 alongside 523 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Greene County's Zone 2 prediction. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Greene County — testing is the only way to know an individual home's actual level.

Testing and mitigation in Greene County

For a Greene 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 Indiana's state radon program

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

Greene County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Greene County carries, the zone explainer covers what it does and doesn't tell you about any one house.