Radon zones in Wyoming
Last updated
EPA’s Map of Radon Zones places 23 Wyoming counties in its three radon potential zones: 21 in Zone 1 (highest), 2 in Zone 2 (moderate), and 0 in Zone 3 (low).
What this means for Wyoming homes
Most Wyoming counties fall in Zone 1. EPA predicts average indoor screening levels above 4 pCi/L across much of Wyoming, so elevated radon is common. Testing is especially worthwhile here, and radon-resistant construction features make sense for new homes.
EPA’s guidance is the same everywhere: test your home, fix it if the level is 4 pCi/L or higher, and consider fixing between 2 and 4 pCi/L. The zone map is from 1993 and should not be used to decide whether a single home needs testing.
Wyoming radon program
EPA lists the following state contact for Wyoming: WY Department of Health, phone 307-777-3480. Website: health.wyo.gov/publichealth/cancer-and-chronic-disease-prevention-unit/cancer/radon. State programs can tell you about local testing data, free or discounted test kits, disclosure rules for home sales, and credentialed radon professionals.
Wyoming counties and their EPA radon zones
| County | EPA radon zone |
|---|---|
| Albany County | Zone 1 |
| Big Horn County | Zone 1 |
| Campbell County | Zone 1 |
| Carbon County | Zone 1 |
| Converse County | Zone 1 |
| Crook County | Zone 1 |
| Fremont County | Zone 1 |
| Goshen County | Zone 1 |
| Hot Springs County | Zone 1 |
| Johnson County | Zone 1 |
| Laramie County | Zone 1 |
| Lincoln County | Zone 1 |
| Natrona County | Zone 1 |
| Niobrara County | Zone 1 |
| Park County | Zone 1 |
| Platte County | Zone 2 |
| Sheridan County | Zone 1 |
| Sublette County | Zone 1 |
| Sweetwater County | Zone 1 |
| Teton County | Zone 1 |
| Uinta County | Zone 1 |
| Washakie County | Zone 1 |
| Weston County | Zone 2 |
County names follow the 2020 Census. Zones from the EPA Map of Radon Zones (text version). Rows marked “zone of” use the zone EPA gave the predecessor or surrounding county.
Next steps: read how to test your home, check a result with the level calculator, or look up a single address by ZIP code.