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Maine Radon Map and Levels by County

Maine's counties span EPA Zones 1 and 2. Homes with elevated levels occur in all three zones, so only a test measures yours.

Data checked By Radon411Methodology

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  • Share at 4+ pCi/L

    37.6%

    1.9 pts above U.S.

    Maine
    37.6%
    U.S.
    35.7%

    11,825 tests across 16 counties, 2008 to 2017

  • Rank among states

    17 of 47

    Middle of the states

    Maine
    37.6%
    North Dakota
    59.3%

    By share, every state pooled the same way, 2008 to 2017

  • Counties in EPA Zone 1

    12 of 16

    Most at highest potential

    Zone 1
    12
    Zone 2
    4

    Most counties sit in Zone 1; Zone 1 is the highest potential

  • Highest county

    48.4%

    York County

    York
    48.4%
    Penobscot
    16.4%

    Counties with 30+ tests, 2008 to 2017

Read a result for Maine

Starts at EPA's action level

4.0pCi/L

EPA’s own thresholds; the figures are the area’s, never this home’s.

EPA’s reading of 4.0 pCi/L

At or above 4 pCi/L

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 4 and aboveEPA says fix it

This result is at or above 4 pCi/L. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. 37.6% of Maine's reported tests reached 4 pCi/L, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Maine, At a glance

Maine at a glance

Predicted: EPA radon zone

16 of 16 counties classified

EPA classifies counties, not states. Of the 16 counties in Maine with a zone, 12 are in Zone 1 and 4 in Zone 2.

  • Zone 1: Highest predicted potentialgreater than 4 pCi/L12 of 16 counties · 75.0%
  • Zone 2: Moderate predicted potential2 to 4 pCi/L4 of 16 counties · 25.0%

An EPA radon zone predicts a whole county. It is not intended to determine whether any individual home should be tested: homes with elevated levels occur in all three zones, and EPA recommends testing every home regardless of zone.

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

CDC test figures, county by county

CDC publishes Maine's radon test figures by county: 16 of its 16 counties have one. Each one's share is in the county list.

How to read these figures

Maine, Compared

Maine radon figures, compared

Calculated by Radon411
Maine, 2008 to 2017, laboratory
37.6%
of 11,825 tests at or above 4 pCi/L, pooled
Against the U.S.
+1.9points
35.7% pooled
Rank among the states
17 of 47
1 is the highest share
Counties with 30 or more tests
16
Highest
48.4%
York County
Lowest
16.4%
Penobscot County

Maine pools to 37.6%: that share of 11,825 reported tests from 16 counties over the 2008 to 2017 laboratory totals reached EPA's action level. Nationally the pooled share is 35.7%: 1.9 points lower than here.

Among 47 states pooled the same way it ranks 17th, with Indiana (38.9%) above it and West Virginia (37.5%) below. York County reports the highest share (48.4% of 1,389 tests) and Penobscot County the lowest (16.4%); the most tests came from Cumberland County, 4,076 of them at 43.5%.

Across its 4 overlapping ten-year totals, the share went from 36.6% (2005 to 2014) to 37.6% (2008 to 2017), within 2 points, with 2006 to 2015 the highest at 37.6%. By band, 11 counties at 30% to 50%, 5 counties at 15% to 30%.

EPA's 1993 map puts 12 of its 16 classified counties in Zone 1; the tests reported since bear that out at 37.6%.

Maine ranked among 47 states by pooled share of tests at or above 4 pCi/L, 2008 to 2017, laboratory
StateRankCountiesTestsAt or above 4 pCi/L
Illinois12 of 47102108,90943.1%
Utah13 of 472828,34241.9%
Pennsylvania14 of 4767203,04541.7%
Idaho15 of 474412,96141.5%
Indiana16 of 479243,14838.9%
Maine17 of 471611,82537.6%
West Virginia18 of 475510,06137.5%
New Hampshire19 of 471015,60835.0%
Tennessee20 of 479531,06633.3%
Missouri21 of 4711558,52530.6%
Virginia22 of 4713153,19930.4%
Maine's highest and lowest counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/L
York County1 of 161,38948.4%
Piscataquis County2 of 164447.7%
Aroostook County3 of 1660845.1%
Cumberland County4 of 164,07643.5%
Oxford County5 of 1639243.1%
Hancock County6 of 1632739.1%
Androscoggin County7 of 161,49736.9%
Lincoln County8 of 1624635.8%
Waldo County9 of 1620932.1%
Kennebec County10 of 1669630.3%
Penobscot County16 of 161,49116.4%
Somerset County15 of 168518.8%
Franklin County14 of 1614129.1%
Knox County13 of 1628729.6%
Washington County12 of 165429.6%
Maine's counties with 30 or more tests, by their own share at or above 4 pCi/L, 2008 to 2017, laboratory
ShareCountiesTheir testsFor example
50% or more00None
30% to 50%119,767York County, Piscataquis County, Aroostook County
15% to 30%52,058Washington County, Knox County, Franklin County
5% to 15%00None
Under 5%00None
Maine ten-year laboratory totals, pooled, against the United States
PeriodCountiesTestsAt or above 4 pCi/LUnited StatesChange from the row before
2008 to 20171611,82537.6%35.7%Level
2007 to 20161611,24037.6%35.8%Level
2006 to 20151610,20337.6%36.3%+1.0 points
2005 to 2014168,95136.6%36.0%First on file

Pooled shares: Radon411's sum of CDC's county counts for one period. CDC publishes no state or national figure.

Maine, Counties

Maine counties by EPA zone

Predicted

The map of Maine, then its 16 counties zone by zone, each with its reported share at or above 4 pCi/L and a report of its own.

Maine radon map by county: EPA radon zones. Map of Maine's 16 counties shaded by EPA radon zone: Zone 1 in red-orange, Zone 2 in amber. 12 in Zone 1, 4 in Zone 2, 0 in Zone 3.
Maine radon map by countyEPA radon zones for Maine's counties: 12 counties in Zone 1, 4 counties in Zone 2, 0 counties in Zone 3.A prediction for each county, not a reading of any home; elevated homes occur in all three zones.

The 12 highest in Maine, 2008 to 2017

Zone 1: highest predicted potential12

Local help

Maine, Local resources

Local resources in Maine

Who to ask in Maine: its radon program, test kits and professionals.

What Maine's program says
Phone
207-287-5676
Email
radon.dhhs@maine.gov
Licensing of radon professionals
Under Maine law, only the owner or occupant of a residence or someone registered with the state to provide these services, may test for radon, install and/or advise on the installation of a radon reduction (mitigation) system.

What it means

Maine, Questions

Questions about radon in Maine

Is radon a problem in Maine?

Maine has 16 counties on EPA's Map of Radon Zones: Zone 1, the highest predicted potential, for 12; Zone 2 for 4; Zone 3 for 0. Pooled from 16 counties, 37.6% of the 11,825 radon tests reported to CDC over the 2008 to 2017 laboratory totals were at or above 4 pCi/L, 17th of 47 states.

Which Maine counties are in EPA radon Zone 1?

Zone 1 holds 12 counties in Maine; the first 8 by name are Androscoggin County, Aroostook County, Cumberland County, Franklin County, Hancock County, Kennebec County, Lincoln County, Oxford County, the rest in the county table on this page.

Which Maine counties have the highest radon?

York County 48.4% (1,389 tests) leads Maine by the share of reported tests at or above 4 pCi/L, 2008 to 2017, laboratory, then Piscataquis County 47.7% (44 tests), Aroostook County 45.1% (608 tests), Cumberland County 43.5% (4,076 tests), Oxford County 43.1% (392 tests).

Which EPA region is Maine in?

Maine is in EPA Region 1: New England.

Products

Maine, Products

Testing a home in Maine

37.6% of the 11,825 tests reported to CDC for Maine over the 2008 to 2017 laboratory totals reached 4 pCi/L: a short-term kit (2 to 90 days) gives a first answer in days, a long-term test the year-round average. A short-term kit (2 to 90 days) is the quick first check for a home in Maine; a long-term test tells the year-round average.

Test kits and monitors3

See every kit and monitor

Best radon monitors for Maine homes, compared

Explore

Cities in Maine with their own page

Radon data is published by county, not by city. Each city page sets the figures of the counties the city lies in side by side.