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RadonVerdict
EPA Zone Data 2026

Montana Radon Map, Levels & Testing Guide

View EPA radon zone classifications for every county in Montana. Open your county to compare basement test meaning, EPA action thresholds, and when mitigation pricing becomes worth checking.

49
Zone 1
High Risk
7
Zone 2
Moderate
0
Zone 3
Low Risk

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Use the fastest valid radon test setup before you compare quotes or ask whether mitigation is worth it.

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Open your county to see its EPA zone, testing meaning, and the point where mitigation becomes worth pricing.

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