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

Wyandotte County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Nationally, Wyandotte County ranks higher in radon potential than 96% of rated counties (the 96th percentile).

Where Wyandotte County sits nationally

Wyandotte County, Kansas is home to about 169,418 people across 151.638 square miles. Averaged across its land area, Wyandotte County runs about 1,117 people per square mile. By population, Wyandotte County is the 115th largest of every county sharing its EPA zone — the 89th percentile by population within that zone. Wyandotte County falls in EPA Radon Region 7, one of 412 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Wyandotte 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. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Wyandotte County will test well under the action level, and EPA's guidance is to test regardless of zone.

Testing and mitigation in Wyandotte County

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

Wyandotte County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.