Radon Risk in New Jersey
EPA zone data and CDC radon averages for all 21 counties in New Jersey.
Tipper on radon in New Jersey
The CDC doesn't have enough statewide testing data to calculate a reliable average for New Jersey. That doesn't mean radon isn't a concern here. It means individual county data, where available, is your best guide. Use the county list below to find the most specific data for where you live.
Looking at the zone breakdown: 7 of New Jersey's 21 counties are EPA Zone 1 (high risk), 11 are Zone 2 (moderate), and 3 are Zone 3 (low). That means 33% 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.
Tipper's recommendation for New Jersey 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
Why New Jersey's Geology Matters
New Jersey's radon risk follows the Reading Prong — a geological formation of uranium-bearing Precambrian rock that crosses the northern part of the state (Hunterdon, Somerset, Morris, and Sussex counties). This formation is one of the most significant radon sources on the East Coast. Southern New Jersey, on coastal plain sediments, has much lower risk.
Radon Disclosure Laws
New Jersey does not require radon testing or disclosure in residential real estate transactions, though it is strongly recommended. The state has specific regulations for radon testing and mitigation businesses.
State Radon Program
New Jersey Department of Environmental Protection — Radon Program
Northern New Jersey sits on the Reading Prong, one of the most significant natural radon sources on the East Coast.
All Counties in New Jersey
Click any county to see its full radon data and local contractors.
Showing 21 of 21 counties in New Jersey. 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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