Utah Radon Levels
7Zone 1 (High)
22Zone 2 (Moderate)
0Zone 3 (Low)
24% of counties in Utah are classified as EPA Zone 1 (highest radon potential), meaning predicted average indoor radon levels exceed 4 pCi/L — the EPA action level. The EPA recommends that all homes be tested for radon, regardless of zone classification.
| County | EPA Zone | Risk Level |
|---|---|---|
| Beaver County | Zone 2 | Moderate Potential |
| Box Elder County | Zone 2 | Moderate Potential |
| Cache County | Zone 2 | Moderate Potential |
| Carbon County | Zone 1 | Highest Potential |
| Daggett County | Zone 2 | Moderate Potential |
| Davis County | Zone 2 | Moderate Potential |
| Duchesne County | Zone 1 | Highest Potential |
| Emery County | Zone 2 | Moderate Potential |
| Garfield County | Zone 2 | Moderate Potential |
| Grand County | Zone 1 | Highest Potential |
| Iron County | Zone 2 | Moderate Potential |
| Juab County | Zone 2 | Moderate Potential |
| Kane County | Zone 2 | Moderate Potential |
| Millard County | Zone 2 | Moderate Potential |
| Morgan County | Zone 2 | Moderate Potential |
| Piute County | Zone 1 | Highest Potential |
| Rich County | Zone 2 | Moderate Potential |
| Salt Lake County | Zone 2 | Moderate Potential |
| San Juan County | Zone 2 | Moderate Potential |
| Sanpete County | Zone 1 | Highest Potential |
| Sevier County | Zone 1 | Highest Potential |
| Summit County | Zone 2 | Moderate Potential |
| Tooele County | Zone 2 | Moderate Potential |
| Uintah County | Zone 1 | Highest Potential |
| Utah County | Zone 2 | Moderate Potential |
| Wasatch County | Zone 2 | Moderate Potential |
| Washington County | Zone 2 | Moderate Potential |
| Wayne County | Zone 2 | Moderate Potential |
| Weber County | Zone 2 | Moderate Potential |