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

EPA's own radon map rates Greene County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. That puts Greene County in the 14th percentile nationally for radon potential — higher than 14% of the counties EPA has rated.

Greene County by the numbers

Greene County, North Carolina is home to about 20,671 people across 266.736 square miles. Averaged across its land area, Greene County runs about 77 people per square mile. By population, Greene County is the 599th largest of every county sharing its EPA zone — the 42nd percentile by population within that zone. EPA's geology-based Region 4 groups Greene County with 735 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Greene County

Greene 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. A Zone 3 rating means Greene County's county-wide average is predicted low, but EPA is explicit that a meaningful share of homes in low-potential zones still test above the action level — a low zone is not a reason to skip testing.

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 North Carolina'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

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