Is Garfield County, WA a radon risk area?

Garfield 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. Rank it against the rest of the country and Garfield County lands in the 34th percentile for radon potential.

Garfield County by the numbers

About 2,404 people live in Garfield County, Washington, spread over 710.835 square miles. Averaged across its land area, Garfield County runs about 3 people per square mile. Rank 997 by population within its EPA zone puts Garfield County at the 3rd percentile among zone peers. Garfield 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

EPA's Zone 2 rating for Garfield County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. A county-wide moderate average, like Garfield County's, can still hide a specific house well above or below it — testing is what actually answers the question.

If Garfield County tests above the action level

Nothing about Garfield County's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find Washington's state radon program

Garfield County's test kit answers today; a Airthings radon monitor keeps answering for Garfield County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

More on how this number was built

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.