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Radon Levels in Lenawee County, Michigan

EPA puts Lenawee County in Zone 1, its highest radon zone, and high results are common there: 56.7% of the 1,907 radon tests reported to CDC (2008 to 2017, laboratory totals) came back at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.

Data checked By Radon411Methodology

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    56.7%

    29.8 pts above MI

    Lenawee
    56.7%
    Michigan
    26.9%

    1,907 tests, 2008 to 2017

  • Median result

    4.6pCi/L

    Action level reached

    Lenawee
    4.6 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    1,907

    16th of 82 by tests

    Lenawee
    1,907
    Oakland
    16,224

    Reported to CDC before any fix, 2008 to 2017

  • EPA radon zone

    Zone 1

    Highest potential

    1. Zone 1
    2. 2
    3. 3

    1 highest, 3 lowest

    EPA predicts over 4 pCi/L indoors

  • Rank in Michigan

    1 of 82

    Top quarter

    Lenawee
    56.7%
    Lenawee
    56.7%

    By share, of 82 with 30+ tests

Read a result for Lenawee County

Starts at Lenawee County's median, 4.6 pCi/L

4.6pCi/L

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

EPA’s reading of 4.6 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. Lenawee County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Lenawee County, At a glance

Lenawee County at a glance

Predicted: EPA radon zone

EPA Zone 1: highest predicted potential

EPA puts all of Lenawee County in and predicts an average indoor of greater than 4 pCi/L (greater than 150 Bq/m³) across the county. That is one forecast for the whole county, not a reading of any address in it; homes above EPA's turn up in all three zones.

USGS geologic potential: High across 69% of the county's area

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

Radon tests reported for Lenawee County, 2008 to 2017, laboratory

Reported results by concentration band, Lenawee County, 2008 to 2017, laboratory
Under 2 pCi/L: 23%2 to 4 pCi/L: 20%4 pCi/L and above: 57%

Of 1,907 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Lenawee County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L44523.3%
2 to 4 pCi/L38120.0%
4 pCi/L and above1,08156.7%
What these figures count

These are the 1,907 tests reported to CDC for Lenawee County over 2008 to 2017 (laboratory totals), many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.

Measured: CDC tracking data. Figure above: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).

How to read these figures

Lenawee County, Compared

Lenawee County radon figures, compared

Calculated by Radon411

More than half: 56.7% of the 1,907 radon tests reported to CDC for Lenawee County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 1st of 82 Michigan counties with 30 or more tests for the same period. That is 29.8 points above the 26.9% pooled from 83 Michigan counties.

The median result, 4.6 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 116.1 pCi/L. The rest split 23.3% under 2 pCi/L and 20.0% from 2 to 4 (Michigan: 46.4% and 26.7%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 56.7% share point the same way here.

No bordering county with a figure for the same period reported a higher share; the closest is Hillsdale County at 54.8%, the lowest Monroe County at 30.4%. Statewide for the same period, Branch County reported the highest share (55.4%) and Muskegon County the lowest (3.2%).

CDC's ten-year totals for Lenawee County went from 1,672 tests (2005 to 2014) to 1,907 (2008 to 2017), the share going from 56.6% to 56.7%.

Nationally, every county with a figure for the same period pools to 35.7%; Lenawee County sits 21.0 points above it. CDC also counts 189 tests taken after mitigation in Lenawee County for the same period: tests in homes where a fix was already in.

Lenawee County against Michigan, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Lenawee County
Lenawee County1,90756.7%4.6 pCi/LThis county
Michigan, pooled83 counties, pooled114,40726.9%Not pooled−29.8 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled−21.0 points
Branch Countyhighest in the state1,04855.4%4.4 pCi/L−1.3 points
Muskegon Countylowest in the state6293.2%1.2 pCi/L−53.5 points
Hillsdale County, MIborders it2,08654.8%4.4 pCi/L−1.9 points
Jackson County, MIborders it2,96449.7%3.9 pCi/L−7.0 points
Fulton County, OHborders it6245.2%3.1 pCi/L−11.5 points
Washtenaw County, MIborders it8,50041.3%3.2 pCi/L−15.4 points
Lucas County, OHborders it1,38140.2%3.0 pCi/L−16.5 points
Monroe County, MIborders it1,37530.4%2.5 pCi/L−26.3 points
Where Lenawee County's reported results fell, 2008 to 2017, laboratory, beside Michigan and the United States
ResultLenawee County testsLenawee County shareMichigan shareU.S. shareAgainst Michigan
Under 2 pCi/L44523.3%46.4%39.6%−23.1 points
2 to 4 pCi/L38120.0%26.7%24.7%−6.7 points
4 pCi/L and above1,08156.7%26.9%35.7%+29.8 points
Lenawee County ranked among the 82 Michigan counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/LMedian
Lenawee County1 of 821,90756.7%4.6 pCi/L
Branch County2 of 821,04855.4%4.4 pCi/L
Hillsdale County3 of 822,08654.8%4.4 pCi/L
Jackson County4 of 822,96449.7%3.9 pCi/L
Livingston County5 of 824,88543.1%3.4 pCi/L
Washtenaw County6 of 828,50041.3%3.2 pCi/L
Dickinson County7 of 8284339.3%3.1 pCi/L
Clinton County8 of 822,31338.5%3.1 pCi/L
Otsego County9 of 821,08038.2%3.2 pCi/L
Ionia County10 of 821,39136.8%2.9 pCi/L
Calhoun County11 of 821,64936.4%3.0 pCi/L
Lenawee County ten-year laboratory totals, against Michigan's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestMichigan, pooledChange from the row before
2008 to 20171,90756.7%4.6 pCi/L116.1 pCi/L26.9%−1.9 points
2007 to 20161,86058.6%4.8 pCi/L116.1 pCi/L26.8%+1.0 points
2006 to 20151,83157.6%4.7 pCi/L116.1 pCi/L26.8%+1.0 points
2005 to 20141,67256.6%4.7 pCi/L95.1 pCi/L26.2%First on file

Pooled shares: Radon411's sum of CDC's county counts for one period.

Lenawee County, State data

Michigan's own radon test data

Measured

What Michigan's own agencies publish about radon tests in Lenawee County, with their period. These are not CDC's figures and are never added to them.

MeasuredState figures, not CDC's

What Michigan EGLE reports for the ZIP codes in Lenawee County

Michigan EGLE publishes its figures by ZIP code, not by county. These are the 22 ZIP codes that lie wholly or partly in Lenawee County, each with the state's own figures for it. Period: About 10 years to 2026-05-15.

ZIP codes in Lenawee County
ZIP codeWhat the state reports
4817643% greater than 4 pCi/L, median 3.2 pCi/L, 351 tests
4922059% greater than 4 pCi/L, median 4.3 pCi/L, 22 tests
4922144% greater than 4 pCi/L, median 3.4 pCi/L, 362 tests
4922816% greater than 4 pCi/L, median 1.7 pCi/L, 44 tests
4922954% greater than 4 pCi/L, median 4.9 pCi/L, 35 tests
4923055% greater than 4 pCi/L, median 4.3 pCi/L, 100 tests
4923362% greater than 4 pCi/L, median 5.2 pCi/L, 29 tests
4923545% greater than 4 pCi/L, median 3.5 pCi/L, 22 tests
4923669% greater than 4 pCi/L, median 6.0 pCi/L, 54 tests
4923829% greater than 4 pCi/L, median 1.7 pCi/L, 7 tests
4924755% greater than 4 pCi/L, median 4.5 pCi/L, 31 tests
4924833% greater than 4 pCi/L, median 2.0 pCi/L, 6 tests
4925351% greater than 4 pCi/L, median 4.0 pCi/L, 45 tests
4925650% greater than 4 pCi/L, median 4.1 pCi/L, 22 tests
4926543% greater than 4 pCi/L, median 3.1 pCi/L, 80 tests
4926738% greater than 4 pCi/L, median 3.1 pCi/L, 8 tests
4926871% greater than 4 pCi/L, median 6.7 pCi/L, 7 tests
4927657% greater than 4 pCi/L, median 4.7 pCi/L, 7 tests
492794 tests, figures not shown
4928667% greater than 4 pCi/L, median 6.2 pCi/L, 233 tests
4928752% greater than 4 pCi/L, median 4.4 pCi/L, 27 tests
4928871% greater than 4 pCi/L, median 7.1 pCi/L, 7 tests
  • EGLE's figures cover first-time tests only, from organizations willing to provide data.
  • EGLE does not publish figures for a ZIP code with fewer than 5 test results.
  • EGLE says the map is not intended to decide whether a home should be tested: all homes should be tested.
  • ZIP code boundaries are postal delivery areas, not legal or administrative boundaries.
  • A ZIP code that crosses the county line is listed whole; its figures cover all of it.

Measured: Michigan EGLE data, About 10 years to 2026-05-15.

Lenawee County, Geology

The ground under Lenawee County

Predicted

USGS's geologic map splits Lenawee County: 68.6% of its land is high radon potential and 31.4% moderate. The map puts 68.5% of Lenawee County in the area it calls Saginaw Lobe Moraine Area and 31.4% in Antrim Shale-Lake deposits. USGS gives the first a radon index of 12, in the high band (12 to 17), and the second 9, in the moderate band (9 to 11).

USGS's geologic areas under Lenawee County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Saginaw Lobe Moraine AreaGlacial deposits derived from Sandstone and shale.High1268.5%
Antrim Shale-Lake depositsAntrim black shale covered by glacial lake deposits.Moderate931.4%

Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.

Lenawee County beside the ground around it

Lenawee County has more high-potential ground than Michigan as a whole: 68.6% of its land against 9.6%. Of the 6 counties that border it, 3 have more high-potential ground, Hillsdale County the most at 100%.

Share of land by USGS radon potential: Lenawee County, the 6 counties bordering it and Michigan
AreaEPA zoneLow potentialModerate potentialHigh potential
Lenawee CountyZone 1None31.4%68.6%
Washtenaw CountyZone 1None15.1%84.9%
Fulton County, OHZone 2None64.9%35.1%
Monroe CountyZone 2None98.3%None
Lucas County, OHZone 2None85.6%13.9%
Hillsdale CountyZone 1NoneNone100%
Jackson CountyZone 1None9.4%90.6%
Michigan83 counties, pooled by land areaVaries45.0%44.3%9.6%

The map rates the ground, not the air in any home.

Local help

Lenawee County, Local resources

Radon testing and mitigation in Lenawee County

Listed radon businesses with an address in Lenawee County:

Listed radon professionals by town: Tecumseh, Clinton, Deerfield

What Michigan's program says
Phone
800-723-6642
Email
Radon@Michigan.gov
Licensing of radon professionals
Michigan does not license or regulate radon testing and mitigation contractors.

What it means

Lenawee County, Questions

Questions about radon in Lenawee County

Are radon levels high in Lenawee County?

Over the 2008 to 2017 laboratory totals, 56.7% of the radon tests reported to CDC for Lenawee County, Michigan were at or above 4 pCi/L, and the median reported pre-mitigation result was 4.6 pCi/L. Of 82 Michigan counties with 30 or more tests for the same period, none reported a higher share; pooled, the state comes to 26.9%.

Which counties border Lenawee County?

Lenawee County borders 6 counties: Washtenaw County, MI, Fulton County, OH, Monroe County, MI, Lucas County, OH, Hillsdale County, MI and Jackson County, MI.

Products

Lenawee County, Products

Testing a home in Lenawee County

In Lenawee County, 56.7% of 1,907 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 26.9% pooled across Michigan. In Zone 1 the year-round level in Lenawee County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.

Test kits and monitors3

See every kit and monitor

Lenawee County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Lenawee County

Explore

Lenawee County, Bordering counties

Counties bordering Lenawee County

Calculated by Radon411

Lenawee County, Cities and towns

Cities and towns in Lenawee County

About 97,779 people live in Lenawee County by the Census Bureau's estimate for July 1, 2025, 1,569 fewer than in 2020 (−1.6%). That works out to 130 people per square mile of land. Its largest town, Adrian, has 20,191 residents, 20.6% of the total. Testing is reported here more often than across the state: CDC's 1,907 reported tests for 2008 to 2017 come to 19.5 for every 1,000 residents (2025 estimate), against 11.3 for Michigan.

From Adrian to Clayton, CDC publishes no figure by town: each reads Lenawee County's.

The cities and towns in Lenawee County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Adrian20,191−2.1%20.6%
Tecumseh8,608−0.7%8.8%
Blissfield3,262−1.8%3.3%
Clinton2,481−1.7%2.5%
Hudson2,347−2.9%2.4%
Morenci2,218−2.4%2.3%
Onsted1,002+0.1%1.0%
Deerfield887−2.6%0.9%
Addison583−2.8%0.6%
Britton557−3.1%0.6%
Cement Cityextends beyond Lenawee County417−1.4%Counted whole
Clayton320−0.6%0.3%

12 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond Lenawee County is counted whole, so it has no share.

Lenawee County, Homes

Homes in Lenawee County

Lenawee County is a place of houses on their own lots: 79% of its 43,747 homes are detached single-family houses, against 72% across Michigan. Half of its homes were built before 1969, close to Michigan's 1972: 42% date from before 1960 and 12% from 2000 or later. Owners live in 79% of the occupied homes (Michigan: 73%), so for most households a test and a fix are their own to order.

Homes in Lenawee County, Michigan, 2019 to 2023
HomesLenawee CountyMichigan
Housing units43,7474,599,683
Detached houses79%72%
In buildings of 5 or more8%13%
Mobile homes6%5%
Built before 196042%36%
Built since 200012%15%
Middle year built19691972
Owner-occupied79%73%

Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.