Polk County, NE: EPA's radon zone, explained

EPA's own radon map rates Polk County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Nationally that's the 71st percentile for radon potential — Polk County outranks 71% of every county EPA has rated.

How Polk County compares

Polk County, Nebraska is home to about 5,269 people across 438.832 square miles. Population density there runs about 12 people per square mile. By population, Polk County is the 914th largest of every county sharing its EPA zone — the 14th percentile by population within that zone. EPA's geology-based Region 7 groups Polk County with 411 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Polk County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. EPA's guidance doesn't change because of a Zone 1 label: test the house. What changes is the reason to not put it off in Polk County specifically.

Testing and mitigation in Polk County

For a Polk 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 Nebraska's state radon program

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

Where Polk County's figures come from

Polk County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.