Doniphan County, KS: EPA's radon zone, explained

EPA's own radon map rates Doniphan County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Rank it against the rest of the country and Doniphan County lands in the 38th percentile for radon potential.

Where Doniphan County sits nationally

Doniphan County, Kansas is home to about 7,575 people across 393.475 square miles. That works out to roughly 19 people per square mile. By population, Doniphan County is the 882nd largest of every county sharing its EPA zone — the 15th percentile by population within that zone. Doniphan 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 Doniphan County

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Doniphan County's Zone 2 prediction lands in the gap between the two. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Doniphan County — testing is the only way to know an individual home's actual level.

Next steps for a home in Doniphan County

For a Doniphan 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 Kansas's state radon program

For Doniphan County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Doniphan 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 Doniphan 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 Doniphan County carries, the zone explainer covers what it does and doesn't tell you about any one house.