Benton County, OR radon potential

EPA's own radon map rates Benton County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. That puts Benton County in the 26th percentile nationally for radon potential — higher than 26% of the counties EPA has rated.

Benton County by the numbers

Benton County, Oregon is home to about 98,899 people across 675.208 square miles. Averaged across its land area, Benton County runs about 146 people per square mile. Within its own EPA zone, Benton County is bigger by population than 79% of the counties that share it. Benton County falls in EPA Radon Region 10, one of 142 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Benton County's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. A Zone 3 label describes Benton County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Testing and mitigation in Benton County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Oregon's state radon program

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

Benton County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Benton County carries, the zone explainer covers what it does and doesn't tell you about any one house.