Wyoming: 23 counties covered
Of 23 rated Wyoming counties, 21 are in EPA's highest radon-potential zone (Zone 1) — but every county page links to testing guidance regardless of zone, because a county rating is a county-wide average, not a reading for any one house.
- Laramie County
- Natrona County
- Campbell County
- Sweetwater County
- Fremont County
- Albany County
- Sheridan County
- Park County
- Teton County
- Lincoln County
- Uinta County
- Carbon County
- Converse County
- Goshen County
- Big Horn County
- Sublette County
- Johnson County
- Platte County
- Crook County
- Washakie County
- Weston County
- Hot Springs County
- Niobrara County