46%tests ≥ 4 pCi/L
346tests on record
—median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Pend Oreille County

ResultShareEPA guidance
Below 2 pCi/L32%Below EPA's levels
2 to 4 pCi/L22%Consider fixing
4 pCi/L or more46%EPA recommends fixing

What the data shows

Where Pend Oreille County sits among Washington's 39 counties with dataEach dot is a county's share of tests at or above 4 pCi/L · Radon test results by county (Washington Tracking Network), 2000–2025
0%20%40%60%

How Pend Oreille County compares

Pend Oreille County has the highest share of high results among its neighboursShare of tests at or above 4 pCi/L · Radon test results by county (Washington Tracking Network), 2000–2025 · whisker: 95% range
Pend Oreille County46%Stevens County44%Spokane County40%Washington 19%
Data table
AreaTests ≥ 4 pCi/LTests
Pend Oreille County46%346
Stevens County44%1,025
Spokane County40%15,679
Washington (39 counties)19%64,932

Same source as Pend Oreille County. Other bordering counties: Bonner County, Idaho, Boundary County, Idaho.

What it means for your home

About 1 in 2 results in Pend Oreille County were at or above 4 pCi/L, where the EPA recommends a fix. Only a test shows your own home's level.

Levels in pCi/L from the EPA. The WHO reference level is 100 Bq/m³, about 2.7 pCi/L.

Test your home

Start with a short-term test (2–90 days) and confirm a result of 4 pCi/L or more with a second test. EPA guide

Sponsored: we earn a commission on purchases through these links. We haven't tested Airthings monitors yet.

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Fixing high radon

No local job records yet. National range: $800–$2,500, average $1,200 (EPA, 2003). Cost guide →

Washington doesn't license radon mitigators; look for NRPP or NRSB certification. Source

Buying or selling here

Washington's seller disclosure statement asks whether the seller knows of substances that may be environmental concerns, including radon gas (RCW 64.06.020). Source

Checked against the official text on 2026-11-03. Not legal advice.

About this data

Source: Radon test results by county (Washington Tracking Network) (Washington State Department of Health). Period: 2000–2025. Tests: 346. Read the methodology →

These are voluntary and real-estate tests, not a random sample of homes, so they describe tested homes rather than every home.

About this page

Published by Ray Roman, editor of Radon by County. Figures are loaded from the cited source and spot-checked against it. Editorial policy · About us