Radon Risk in Rhode Island
EPA zone data and CDC radon averages for all 5 counties in Rhode Island.
Tipper on radon in Rhode Island
Rhode Island's statewide average radon level is 3.68 pCi/L, which falls below the EPA's action level of 4 pCi/L. That's a reasonable baseline, but statewide averages can mask significant county-to-county variation. Some parts of Rhode Island run considerably higher than others.
Looking at the zone breakdown: 2 of Rhode Island's 5 counties are EPA Zone 1 (high risk), 2 are Zone 2 (moderate), and 1 are Zone 3 (low). That means 40% 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 Rhode Island, the spread is notable. Washington County has the highest measured average in the state at 5.4 pCi/L. Bristol County sits at the other end with 2.6 pCi/L. 1 county has 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 Rhode Island 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 Rhode Island's Geology Matters
Rhode Island has moderate radon risk driven by its granitic and metamorphic bedrock. The Narragansett Basin contains sedimentary rock with lower radon potential, while the surrounding uplands of granite and gneiss produce higher readings. Glacial deposits of variable thickness overlie the bedrock throughout the state.
Radon Disclosure Laws
Rhode Island requires sellers to complete a disclosure form that covers known environmental conditions, but does not have a radon-specific mandate.
Highest Radon Averages
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All Counties in Rhode Island
Click any county to see its full radon data and local contractors.
Showing 5 of 5 counties in Rhode Island. Zone classifications from the EPA. Average pCi/L from CDC tracking data.
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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.
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