EPA Zone Data 2026
Massachusetts Radon Map, Levels & Testing Guide
View EPA radon zone classifications for every county in Massachusetts. Open your county to compare basement test meaning, EPA action thresholds, and when mitigation pricing becomes worth checking.
3
Zone 1
High Risk
High Risk
10
Zone 2
Moderate
Moderate
1
Zone 3
Low Risk
Low Risk
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Browse Counties
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Open your county to see its EPA zone, testing meaning, and the point where mitigation becomes worth pricing.
Barnstable County
Zone 2
Berkshire County
Zone 2
Bristol County
Zone 2
Dukes County
Zone 2
Essex County
Zone 1
Franklin County
Zone 2
Hampden County
Zone 2
Hampshire County
Zone 2
Middlesex County
Zone 1
Nantucket County
Zone 2
Norfolk County
Zone 2
Plymouth County
Zone 2
Worcester County
Zone 1
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