Counties with the Highest Radon Potential in New Jersey
The top 21 of 21 New Jersey counties on GIS Map, ranked by EPA radon zone, where zone 1 carries the highest predicted indoor radon potential and zone 3 the lowest.
| # | County | EPA radon zone |
|---|---|---|
| 1 | Atlantic County | 3 |
| 2 | Cape May County | 3 |
| 3 | Ocean County | 3 |
| 4 | Bergen County | 2 |
| 5 | Burlington County | 2 |
| 6 | Camden County | 2 |
| 7 | Cumberland County | 2 |
| 8 | Essex County | 2 |
| 9 | Gloucester County | 2 |
| 10 | Hudson County | 2 |
| 11 | Middlesex County | 2 |
| 12 | Passaic County | 2 |
| 13 | Salem County | 2 |
| 14 | Union County | 2 |
| 15 | Hunterdon County | 1 |
| 16 | Mercer County | 1 |
| 17 | Monmouth County | 1 |
| 18 | Morris County | 1 |
| 19 | Somerset County | 1 |
| 20 | Sussex County | 1 |
| 21 | Warren County | 1 |
Source: EPA Map of Radon Zones (September 2025). All counties with data are ranked. Estimates carry margins of error.
Citing this page: GIS Map, “Counties with the Highest Radon Potential in New Jersey”, https://gismap.land/rankings/new-jersey/highest-radon-counties. Figures from EPA Map of Radon Zones (September 2025).
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