Henry County, IN radon potential

EPA places Henry County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Henry County sits at the 90th percentile nationally for radon potential — above 90 of every 100 rated counties.

How Henry County compares

Henry County, Indiana is home to about 49,081 people across 391.877 square miles. That works out to roughly 125 people per square mile. Within its own EPA zone, Henry County is bigger by population than 70% of the counties that share it. EPA's geology-based Region 5 groups Henry County with 523 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Henry County

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Henry County's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. Being in Zone 1 raises the odds Henry County homes test above the action level, but it does not mean any specific house does — EPA recommends every home be tested, in every zone, because the only way to know is to test.

If Henry County tests above the action level

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

Where Henry 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. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.