Radon Risk in Wyoming
EPA zone data and CDC radon averages for all 23 counties in Wyoming.
Tipper on radon in Wyoming
Wyoming has a statewide average radon level of 5.91 pCi/L, above the EPA's action level of 4 pCi/L. That puts Wyoming among the higher-risk states in the country for indoor radon. If you live here, testing your home is genuinely important.
Looking at the zone breakdown: 21 of Wyoming's 23 counties are EPA Zone 1 (high risk), 2 are Zone 2 (moderate). That means 91% of the state falls into the highest risk category, counties where the EPA predicts average indoor levels above 4 pCi/L. Use the county list below to find your area and see the most specific data available.
Within Wyoming, the spread is notable. Lincoln County has the highest measured average in the state at 12.6 pCi/L. Uinta County sits at the other end with 3.1 pCi/L. 17 counties have a measured average above 4 pCi/L. Remember: these are averages. Individual homes can test significantly higher or lower than their county average depending on construction, foundation type, and ventilation.
Tipper's recommendation for Wyoming residents: if you haven't tested your home, start there. A short-term test kit costs around $15 and gives you a result in 48 hours. If your home tests at or above 4 pCi/L, a professional mitigation system (typically $800–$2,000 depending on your foundation and home size) will reliably bring levels down.
Sources: EPA Radon Zone Map, CDC Environmental Public Health Tracking Network
Why Wyoming's Geology Matters
Wyoming has moderate radon risk that varies by region. The Wind River Range and other mountain areas with granitic bedrock have higher radon potential. The Powder River Basin and other sedimentary basins have variable risk depending on uranium content. Cold winters and altitude drive tight building construction, which can concentrate indoor radon.
Radon Disclosure Laws
Wyoming does not have a radon-specific disclosure requirement for real estate transactions.
Highest Radon Averages
Lowest Radon Averages
All Counties in Wyoming
Click any county to see its full radon data and local contractors.
Showing 23 of 23 counties in Wyoming. Zone classifications from the EPA. Average pCi/L from CDC tracking data.
Not sure where to start?
A short-term test kit tells you your home's actual radon level in 48 hours. Tipper has picked the best options at every price point. All EPA-approved, all lab-fee included.
Contractors
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