Decatur County, IN radon potential

EPA's own radon map rates Decatur County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Rank it against the rest of the country and Decatur County lands in the 84th percentile for radon potential.

Where Decatur County sits nationally

Decatur County, Indiana is home to about 26,421 people across 372.568 square miles. That works out to roughly 71 people per square mile. Within its own EPA zone, Decatur County is bigger by population than 53% of the counties that share it. EPA's geology-based Region 5 groups Decatur County with 523 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Decatur 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. 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 Decatur County specifically.

Testing and mitigation in Decatur County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Indiana's state radon program

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

Where Decatur County's figures come from

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. Whatever zone Decatur County carries, the zone explainer covers what it does and doesn't tell you about any one house.