Radon levels in Maine

Verified county-level radon indicators are available for 16 Maine counties. Select a county for its source period and sample details.

High results are most common in York County (48%) and least common in Penobscot County (16%)Share of tests at or above 4 pCi/L by county · Radon test results from laboratories, 2008–2017 · 16 of 16 counties have data
Androscoggin County: 37% of tests at or above 4 pCi/L · 1,497 testsAroostook County: 45% of tests at or above 4 pCi/L · 608 testsCumberland County: 44% of tests at or above 4 pCi/L · 4,076 testsFranklin County: 29% of tests at or above 4 pCi/L · 141 testsHancock County: 39% of tests at or above 4 pCi/L · 327 testsKennebec County: 30% of tests at or above 4 pCi/L · 696 testsKnox County: 30% of tests at or above 4 pCi/L · 287 testsLincoln County: 36% of tests at or above 4 pCi/L · 246 testsOxford County: 43% of tests at or above 4 pCi/L · 392 testsPenobscot County: 16% of tests at or above 4 pCi/L · 1,491 testsPiscataquis County: 48% of tests at or above 4 pCi/L · 44 testsSagadahoc County: 30% of tests at or above 4 pCi/L · 283 testsSomerset County: 19% of tests at or above 4 pCi/L · 85 testsWaldo County: 32% of tests at or above 4 pCi/L · 209 testsWashington County: 30% of tests at or above 4 pCi/L · 54 testsYork County: 48% of tests at or above 4 pCi/L · 1,389 tests
  • Under 10%
  • 10–20%
  • 20–30%
  • 30–40%
  • 40% or more
  • No data

Counties

CountyTests% ≥ 4 pCi/LMedian (pCi/L)EPA zone (1993)Source
Androscoggin County1,49737%2.8Zone 1Radon test results from laboratories through 2017
Aroostook County60845%3.5Zone 1Radon test results from laboratories through 2017
Cumberland County4,07644%3.2Zone 1Radon test results from laboratories through 2017
Franklin County14129%1.8Zone 1Radon test results from laboratories through 2017
Hancock County32739%2.6Zone 1Radon test results from laboratories through 2017
Kennebec County69630%2.1Zone 1Radon test results from laboratories through 2017
Knox County28730%2.3Zone 2Radon test results from laboratories through 2017
Lincoln County24636%2.5Zone 1Radon test results from laboratories through 2017
Oxford County39243%3.3Zone 1Radon test results from laboratories through 2017
Penobscot County1,49116%0.8Zone 1Radon test results from laboratories through 2017
Piscataquis County4448%3.5Zone 1Radon test results from laboratories through 2017
Sagadahoc County28330%2.1Zone 2Radon test results from laboratories through 2017
Somerset County8519%1.5Zone 1Radon test results from laboratories through 2017
Waldo County20932%2.3Zone 2Radon test results from laboratories through 2017
Washington County5430%1.6Zone 2Radon test results from laboratories through 2017
York County1,38948%3.7Zone 1Radon test results from laboratories through 2017

Test your home

County figures show how often tests come back high, not the level in your home. Only a test tells you that: see how to test for radon.

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