What EPA's radon map says about Kosciusko County

EPA's own radon map rates Kosciusko County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Nationally, Kosciusko County ranks higher in radon potential than 93% of rated counties (the 93rd percentile).

How Kosciusko County compares

About 80,669 people live in Kosciusko County, Indiana, spread over 531.448 square miles. Population density there runs about 152 people per square mile. Among counties sharing Kosciusko County's EPA zone, it outranks 79% of them by population. Kosciusko County falls in EPA Radon Region 5, one of 524 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Kosciusko County carries a Zone 1 label because its predicted average clears 4 pCi/L outright — three-plus times the 0.4 pCi/L typical outdoors and above the 1.3 pCi/L most homes see. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Kosciusko County will test well under the action level, and EPA's guidance is to test regardless of zone.

Testing and mitigation in Kosciusko County

Mitigation cost doesn't depend on Kosciusko 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 Indiana's state radon program

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

More on how this number was built

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.