Oregon Radon Levels
0Zone 1 (High)
21Zone 2 (Moderate)
15Zone 3 (Low)
No counties in Oregon are classified as Zone 1 (highest risk), but 21 counties are Zone 2 (moderate potential). The EPA recommends testing all homes regardless of zone classification, as elevated radon can occur in any zone.
| County | EPA Zone | Risk Level |
|---|---|---|
| Baker County | Zone 2 | Moderate Potential |
| Benton County | Zone 3 | Lowest Potential |
| Clackamas County | Zone 3 | Lowest Potential |
| Clatsop County | Zone 2 | Moderate Potential |
| Columbia County | Zone 2 | Moderate Potential |
| Coos County | Zone 3 | Lowest Potential |
| Crook County | Zone 2 | Moderate Potential |
| Curry County | Zone 3 | Lowest Potential |
| Deschutes County | Zone 3 | Lowest Potential |
| Douglas County | Zone 3 | Lowest Potential |
| Gilliam County | Zone 2 | Moderate Potential |
| Grant County | Zone 2 | Moderate Potential |
| Harney County | Zone 2 | Moderate Potential |
| Hood River County | Zone 2 | Moderate Potential |
| Jackson County | Zone 3 | Lowest Potential |
| Jefferson County | Zone 2 | Moderate Potential |
| Josephine County | Zone 3 | Lowest Potential |
| Klamath County | Zone 2 | Moderate Potential |
| Lake County | Zone 2 | Moderate Potential |
| Lane County | Zone 3 | Lowest Potential |
| Lincoln County | Zone 3 | Lowest Potential |
| Linn County | Zone 3 | Lowest Potential |
| Malheur County | Zone 2 | Moderate Potential |
| Marion County | Zone 3 | Lowest Potential |
| Morrow County | Zone 2 | Moderate Potential |
| Multnomah County | Zone 2 | Moderate Potential |
| Polk County | Zone 3 | Lowest Potential |
| Sherman County | Zone 2 | Moderate Potential |
| Tillamook County | Zone 3 | Lowest Potential |
| Umatilla County | Zone 2 | Moderate Potential |
| Union County | Zone 2 | Moderate Potential |
| Wallowa County | Zone 3 | Lowest Potential |
| Wasco County | Zone 2 | Moderate Potential |
| Washington County | Zone 2 | Moderate Potential |
| Wheeler County | Zone 2 | Moderate Potential |
| Yamhill County | Zone 2 | Moderate Potential |