Skip to content
RADON411

Locations and reports

Radon Levels in Carroll County, Ohio

EPA puts Carroll County in Zone 1, its highest radon zone, and high results are common there: 57.4% of the 486 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

    57.4%

    5.1 pts above OH

    Carroll
    57.4%
    Ohio
    52.3%

    486 tests, 2008 to 2017

  • Median result

    4.8pCi/L

    Action level reached

    Carroll
    4.8 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    486

    40th of 79 by tests

    Carroll
    486
    Franklin
    16,142

    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 Ohio

    36 of 79

    Middle half

    Carroll
    57.4%
    Pickaway
    81.4%

    By share, of 79 with 30+ tests

Read a result for Carroll County

Starts at Carroll County's median, 4.8 pCi/L

4.8pCi/L

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

EPA’s reading of 4.8 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. Carroll County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Carroll County, At a glance

Carroll County at a glance

Predicted: EPA radon zone

EPA Zone 1: highest predicted potential

EPA puts all of Carroll 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 88% of the county's area

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

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

Reported results by concentration band, Carroll County, 2008 to 2017, laboratory
Under 2 pCi/L: 21%2 to 4 pCi/L: 22%4 pCi/L and above: 57%

Of 486 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Carroll County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L10321.2%
2 to 4 pCi/L10421.4%
4 pCi/L and above27957.4%
What these figures count

These are the 486 tests reported to CDC for Carroll 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

Carroll County, Compared

Carroll County radon figures, compared

Calculated by Radon411

More than half: 57.4% of the 486 radon tests reported to CDC for Carroll County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 36th of 79 Ohio counties with 30 or more tests for the same period. That is 5.1 points above the 52.3% pooled from 88 Ohio counties.

The median result, 4.8 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 451.9 pCi/L. The rest split 21.2% under 2 pCi/L and 21.4% from 2 to 4 (Ohio: 23.1% and 24.6%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 57.4% share point the same way here.

2 of its 5 bordering counties with figures ran higher, led by Tuscarawas County at 66.4%; Columbiana County reported 49.1%. Statewide for the same period, Pickaway County reported the highest share (81.4%) and Cuyahoga County the lowest (21.7%).

CDC's ten-year totals for Carroll County went from 424 tests (2005 to 2014) to 486 (2008 to 2017), the share going from 55.9% to 57.4%.

Nationally, every county with a figure for the same period pools to 35.7%; Carroll County sits 21.7 points above it. CDC also counts 15 tests taken after mitigation in Carroll County for the same period: tests in homes where a fix was already in.

Carroll County against Ohio, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Carroll County
Carroll County48657.4%4.8 pCi/LThis county
Ohio, pooled88 counties, pooled98,84052.3%Not pooled−5.1 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled−21.7 points
Pickaway Countyhighest in the state18381.4%9.5 pCi/L+24.0 points
Cuyahoga Countylowest in the state10,09221.7%2.0 pCi/L−35.7 points
Tuscarawas County, OHborders it54766.4%5.6 pCi/L+9.0 points
Stark County, OHborders it3,31760.1%4.9 pCi/L+2.7 points
Harrison County, OHborders it4450.0%4.1 pCi/L−7.4 points
Jefferson County, OHborders it27149.8%3.9 pCi/L−7.6 points
Columbiana County, OHborders it66249.1%3.8 pCi/L−8.3 points
Where Carroll County's reported results fell, 2008 to 2017, laboratory, beside Ohio and the United States
ResultCarroll County testsCarroll County shareOhio shareU.S. shareAgainst Ohio
Under 2 pCi/L10321.2%23.1%39.6%−1.9 points
2 to 4 pCi/L10421.4%24.6%24.7%−3.2 points
4 pCi/L and above27957.4%52.3%35.7%+5.1 points
Carroll County ranked among the 79 Ohio counties with 30 or more tests, by share at or above 4 pCi/L, 2008 to 2017, laboratory
CountyRankTestsAt or above 4 pCi/LMedian
Seneca County31 of 7954058.9%4.9 pCi/L
Greene County32 of 792,60258.6%4.9 pCi/L
Monroe County33 of 794858.3%5.0 pCi/L
Mercer County34 of 7914957.7%5.1 pCi/L
Clark County35 of 791,44757.5%4.9 pCi/L
Carroll County36 of 7948657.4%4.8 pCi/L
Allen County37 of 7923856.7%5.0 pCi/L
Highland County38 of 796756.7%4.8 pCi/L
Muskingum County39 of 7939156.3%4.9 pCi/L
Pike County40 of 795756.1%4.5 pCi/L
Erie County41 of 791,65154.5%4.4 pCi/L
Carroll County ten-year laboratory totals, against Ohio's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestOhio, pooledChange from the row before
2008 to 201748657.4%4.8 pCi/L451.9 pCi/L52.3%+0.3 points
2007 to 201646657.1%4.8 pCi/L451.9 pCi/L52.8%+0.4 points
2006 to 201544656.7%4.8 pCi/L451.9 pCi/L52.9%+0.8 points
2005 to 201442455.9%4.6 pCi/L451.9 pCi/L52.4%First on file

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

Carroll County, Geology

The ground under Carroll County

Predicted

Most of the ground under Carroll County is one class on USGS's geologic map: 88.2% of its land is high radon potential, with 11.8% moderate. The map puts 88.2% of Carroll County in the area it calls Area of Elevated Radioactivity and 11.8% in Glaciated Plateau. USGS gives the first a radon index of 12, in the high band (12 to 17), and the second 11, in the moderate band (9 to 11).

USGS's geologic areas under Carroll County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Area of Elevated RadioactivityPennsylvanian shale, sandstone, coal, and limestone.High1288.2%
Glaciated PlateauDevonian, Mississippian and Permian carbonates and shales.Moderate1111.8%

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

Carroll County beside the ground around it

Carroll County has more high-potential ground than Ohio as a whole: 88.2% of its land against 62.8%. Of the 5 counties that border it, 3 have more high-potential ground, Harrison County the most at 100%.

Share of land by USGS radon potential: Carroll County, the 5 counties bordering it and Ohio
AreaEPA zoneLow potentialModerate potentialHigh potential
Carroll CountyZone 1None11.8%88.2%
Columbiana CountyZone 1None39.2%60.8%
Stark CountyZone 1None56.2%43.8%
Harrison CountyZone 1NoneNone100%
Jefferson CountyZone 1NoneNone100%
Tuscarawas CountyZone 1NoneNone100%
Ohio88 counties, pooled by land areaVariesNone37.2%62.8%

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

Local help

Carroll County, Local resources

Radon testing and mitigation in Carroll County

Listed radon businesses with an address in Carroll County:

Listed radon professionals by town: Sherrodsville

What Ohio's program says
Phone
614-728-0272
Email
indoor.radon@odh.ohio.gov
Licensing of radon professionals
This program licenses companies and persons directly involved with the radon testing and mitigation industry.

What it means

Carroll County, Questions

Questions about radon in Carroll County

Are radon levels high in Carroll County?

Over the 2008 to 2017 laboratory totals, 57.4% of the radon tests reported to CDC for Carroll County, Ohio were at or above 4 pCi/L, and the median reported pre-mitigation result was 4.8 pCi/L. Of 79 Ohio counties with 30 or more tests for the same period, 35 reported a higher share; pooled, the state comes to 52.3%.

Which counties border Carroll County?

Carroll County borders 5 counties: Columbiana County, Stark County, Harrison County, Jefferson County and Tuscarawas County.

Products

Carroll County, Products

Testing a home in Carroll County

In Carroll County, 57.4% of 486 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 52.3% pooled across Ohio. In Zone 1 the year-round level in Carroll 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

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

Explore

Carroll County, Bordering counties

Counties bordering Carroll County

Calculated by Radon411

Carroll County, Cities and towns

Cities and towns in Carroll County

About 26,475 people live in Carroll County by the Census Bureau's estimate for July 1, 2025, 286 fewer than in 2020 (−1.1%). That works out to 67 people per square mile of land. Minerva, the largest place on its list (3,697 residents in all), extends beyond Carroll County, so no share of the total is worked out for it. Testing is reported here more often than across the state: CDC's 486 reported tests for 2008 to 2017 come to 18.4 for every 1,000 residents (2025 estimate), against 8.3 for Ohio.

From Minerva to Leesville, CDC publishes no figure by town: each reads Carroll County's.

The cities and towns in Carroll County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Minervaextends beyond Carroll County3,697+0.2%Counted whole
Carrollton3,052−1.8%11.5%
Malvern1,092−0.9%4.1%
Magnoliaextends beyond Carroll County1,013−0.2%Counted whole
Dellroy262−1.9%1.0%
Sherrodsville217−2.3%0.8%
Leesville126−0.8%0.5%

7 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 Carroll County is counted whole, so it has no share.

Carroll County, Homes

Homes in Carroll County

Carroll County is a place of houses on their own lots: 81% of its 13,391 homes are detached single-family houses, against 69% across Ohio. Half of its homes were built before 1973, close to Ohio's 1970: 36% date from before 1960 and 13% from 2000 or later. Owners live in 78% of the occupied homes (Ohio: 67%), so for most households a test and a fix are their own to order.

Homes in Carroll County, Ohio, 2019 to 2023
HomesCarroll CountyOhio
Housing units13,3915,271,573
Detached houses81%69%
In buildings of 5 or more3%15%
Mobile homes11%4%
Built before 196036%38%
Built since 200013%16%
Middle year built19731970
Owner-occupied78%67%

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