Benson County, ND: EPA's radon zone, explained

EPA's own radon map rates Benson 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 — Benson County outranks 71% of every county EPA has rated.

How Benson County compares

Benson County, North Dakota is home to about 5,756 people across 1,388.555 square miles. That works out to roughly 4 people per square mile. By population, Benson County is the 895th largest of every county sharing its EPA zone — the 16th percentile by population within that zone. Geologically, Benson County is grouped into EPA Region 8 alongside 290 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Benson County's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. Some Benson 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.

Testing and mitigation in Benson County

For a Benson 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 North Dakota's state radon program

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

The methodology guide shows exactly which EPA and Census sources feed Benson County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.