Sherman County, OR radon potential

Sherman County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Nationally, Sherman County ranks higher in radon potential than 34% of rated counties (the 34th percentile).

Where Sherman County sits nationally

Sherman County, Oregon is home to about 2,002 people across 823.614 square miles. Population density there runs about 2 people per square mile. Within its own EPA zone, Sherman County is bigger by population than 3% of the counties that share it. Sherman 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

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Sherman County's Zone 2 prediction. Middle-of-the-pack doesn't mean risk-free for any one Sherman County address — a moderate county average still leaves individual homes to test either side of it.

Next steps for a home in Sherman 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 Sherman County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Sherman County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

Where Sherman County's figures come from

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