What EPA's radon map says about McKean County

McKean 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. Rank it against the rest of the country and McKean County lands in the 53rd percentile for radon potential.

Where McKean County sits nationally

About 39,478 people live in McKean County, Pennsylvania, spread over 979.694 square miles. That works out to roughly 40 people per square mile. Among counties sharing McKean County's EPA zone, it outranks 61% of them by population. EPA's geology-based Region 3 groups McKean County with 244 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

McKean County's Zone 2 prediction clears the 1.3 pCi/L national indoor average without reaching EPA's own 4 pCi/L point for recommending a fix. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in McKean County — testing is the only way to know an individual home's actual level.

Testing and mitigation in McKean County

Mitigation cost doesn't depend on McKean 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 Pennsylvania's state radon program

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

More on how this number was built

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