What EPA's radon map says about Osborne County

EPA's own radon map rates Osborne County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Osborne County sits at the 69th percentile nationally for radon potential — above 69 of every 100 rated counties.

How Osborne County compares

About 3,353 people live in Osborne County, Kansas, spread over 892.516 square miles. Population density there runs about 4 people per square mile. Among counties sharing Osborne County's EPA zone, it outranks 9% of them by population. Osborne County falls in EPA Radon Region 7, one of 412 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Where the national indoor average runs about 1.3 pCi/L, Osborne County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. Some Osborne County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

Testing and mitigation in Osborne County

Mitigation cost doesn't depend on Osborne 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 Kansas's state radon program

Osborne County's test kit answers today; a Airthings radon monitor keeps answering for Osborne 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

The methodology guide shows exactly which EPA and Census sources feed Osborne County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.