Osage County, KS: EPA's radon zone, explained

EPA places Osage County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 44th percentile for radon potential — Osage County outranks 44% of every county EPA has rated.

Where Osage County sits nationally

Osage County, Kansas is home to about 15,737 people across 705.506 square miles. Averaged across its land area, Osage County runs about 22 people per square mile. By population, Osage County is the 701st largest of every county sharing its EPA zone — the 32nd percentile by population within that zone. Geologically, Osage County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

Zone vs. an actual test

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Osage County's Zone 2 prediction lands in the gap between the two. Nothing about a Zone 2 label lowers the case for testing in Osage County — EPA recommends it in every zone, moderate included.

Next steps for a home in Osage County

For a Osage 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 Kansas's state radon program

For Osage County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Osage County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

Where Osage County's figures come from

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