Bourbon County, KY: EPA's radon zone, explained

EPA places Bourbon 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. Nationally, Bourbon County ranks higher in radon potential than 82% of rated counties (the 82nd percentile).

How Bourbon County compares

Bourbon County, Kentucky is home to about 20,333 people across 289.75 square miles. Averaged across its land area, Bourbon County runs about 70 people per square mile. By population, Bourbon County is the 571st largest of every county sharing its EPA zone — the 46th percentile by population within that zone. Bourbon County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Where the national indoor average runs about 1.3 pCi/L, Bourbon County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. Some Bourbon 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.

If Bourbon County tests above the action level

For a Bourbon 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 Kentucky's state radon program

For Bourbon County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Bourbon 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 Bourbon County's figures come from

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