Daviess County, MO: EPA's radon zone, explained

EPA's own radon map rates Daviess County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. That puts Daviess County in the 39th percentile nationally for radon potential — higher than 39% of the counties EPA has rated.

Where Daviess County sits nationally

Daviess County, Missouri is home to about 8,541 people across 563.282 square miles. Averaged across its land area, Daviess County runs about 15 people per square mile. By population, Daviess County is the 851st largest of every county sharing its EPA zone — the 18th percentile by population within that zone. Daviess County falls in EPA Radon Region 7, one of 412 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Daviess County

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Daviess County's Zone 2 prediction lands in the gap between the two. A county-wide moderate average, like Daviess County's, can still hide a specific house well above or below it — testing is what actually answers the question.

Next steps for a home in Daviess County

For a Daviess 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 Missouri's state radon program

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

Where Daviess County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Daviess County's numbers. Whatever zone Daviess County carries, the zone explainer covers what it does and doesn't tell you about any one house.