What EPA's radon map says about Delaware County

Delaware County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. That puts Delaware County in the 89th percentile nationally for radon potential — higher than 89% of the counties EPA has rated.

How Delaware County compares

About 44,191 people live in Delaware County, New York, spread over 1,442.596 square miles. That works out to roughly 31 people per square mile. Among counties sharing Delaware County's EPA zone, it outranks 67% of them by population. Geologically, Delaware County is grouped into EPA Region 2 alongside 82 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Delaware County's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. EPA's guidance doesn't change because of a Zone 1 label: test the house. What changes is the reason to not put it off in Delaware County specifically.

Testing and mitigation in Delaware County

Mitigation cost doesn't depend on Delaware County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find New York's state radon program

Delaware County's test kit answers today; a Airthings radon monitor keeps answering for Delaware County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

More on how this number was built

Delaware County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.