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Radon Levels in Licking County, Ohio

EPA puts Licking County in Zone 1, its highest radon zone, and high results are common there: 71.2% of the 4,694 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

    71.2%

    18.9 pts above OH

    Licking
    71.2%
    Ohio
    52.3%

    4,694 tests, 2008 to 2017

  • Median result

    7.0pCi/L

    Action level reached

    Licking
    7.0 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of the tests, 2008 to 2017

  • Tests reported

    4,694

    4th of 79 by tests

    Licking
    4,694
    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

    7 of 79

    Top quarter

    Licking
    71.2%
    Pickaway
    81.4%

    By share, of 79 with 30+ tests

Read a result for Licking County

Starts at Licking County's median, 7.0 pCi/L

7.0pCi/L

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

EPA’s reading of 7.0 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. Licking County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Licking County, At a glance

Licking County at a glance

Predicted: EPA radon zone

EPA Zone 1: highest predicted potential

EPA puts all of Licking 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 100% of the county's area

Predicted: EPA Map of Radon Zones

Measured: tests reported to CDC

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

Reported results by concentration band, Licking County, 2008 to 2017, laboratory
Under 2 pCi/L: 12%2 to 4 pCi/L: 17%4 pCi/L and above: 71%

Of 4,694 pre-mitigation tests reported to CDC, not homes in this area.

Reported results by concentration band, Licking County, 2008 to 2017, laboratory: data table
Result bandTests MeasuredShare Measured
Under 2 pCi/L55611.8%
2 to 4 pCi/L79416.9%
4 pCi/L and above3,34471.2%
What these figures count

These are the 4,694 tests reported to CDC for Licking 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

Licking County, Compared

Licking County radon figures, compared

Calculated by Radon411

More than half: 71.2% of the 4,694 radon tests reported to CDC for Licking County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 7th of 79 Ohio counties with 30 or more tests for the same period. That is 18.9 points above the 52.3% pooled from 88 Ohio counties.

The median result, 7.0 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 649.0 pCi/L. The rest split 11.8% under 2 pCi/L and 16.9% from 2 to 4 (Ohio: 23.1% and 24.6%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 71.2% share point the same way here.

4 of its 7 bordering counties with figures ran higher, led by Fairfield County at 76.8%; Perry County reported 48.9%. 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 Licking County went from 4,088 tests (2005 to 2014) to 4,694 (2008 to 2017), the share going from 70.9% to 71.2%.

Nationally, every county with a figure for the same period pools to 35.7%; Licking County sits 35.5 points above it. CDC also counts 170 tests taken after mitigation in Licking County for the same period: tests in homes where a fix was already in.

Licking County against Ohio, the United States and nearby counties, 2008 to 2017, laboratory
AreaTestsAt or above 4 pCi/LMedianDifference from Licking County
Licking County4,69471.2%7.0 pCi/LThis county
Ohio, pooled88 counties, pooled98,84052.3%Not pooled−18.9 points
United States, pooled2,661 counties, pooled2,013,54435.7%Not pooled−35.5 points
Pickaway Countyhighest in the state18381.4%9.5 pCi/L+10.2 points
Cuyahoga Countylowest in the state10,09221.7%2.0 pCi/L−49.5 points
Fairfield County, OHborders it1,17576.8%7.4 pCi/L+5.6 points
Delaware County, OHborders it3,73072.2%6.4 pCi/L+1.0 points
Knox County, OHborders it1,53072.0%8.1 pCi/L+0.8 points
Franklin County, OHborders it16,14271.9%6.8 pCi/L+0.7 points
Coshocton County, OHborders it11258.9%5.1 pCi/L−12.3 points
Muskingum County, OHborders it39156.3%4.9 pCi/L−14.9 points
Perry County, OHborders it9048.9%3.8 pCi/L−22.3 points
Where Licking County's reported results fell, 2008 to 2017, laboratory, beside Ohio and the United States
ResultLicking County testsLicking County shareOhio shareU.S. shareAgainst Ohio
Under 2 pCi/L55611.8%23.1%39.6%−11.3 points
2 to 4 pCi/L79416.9%24.6%24.7%−7.7 points
4 pCi/L and above3,34471.2%52.3%35.7%+18.9 points
Licking 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
Fairfield County2 of 791,17576.8%7.4 pCi/L
Logan County3 of 7975573.6%7.9 pCi/L
Delaware County4 of 793,73072.2%6.4 pCi/L
Knox County5 of 791,53072.0%8.1 pCi/L
Franklin County6 of 7916,14271.9%6.8 pCi/L
Licking County7 of 794,69471.2%7.0 pCi/L
Auglaize County8 of 7913971.2%6.5 pCi/L
Champaign County9 of 7959671.1%6.8 pCi/L
Madison County10 of 7954967.4%5.7 pCi/L
Ross County11 of 7936867.1%7.0 pCi/L
Tuscarawas County12 of 7954766.4%5.6 pCi/L
Licking County ten-year laboratory totals, against Ohio's pooled share
PeriodTestsAt or above 4 pCi/LMedianHighestOhio, pooledChange from the row before
2008 to 20174,69471.2%7.0 pCi/L649.0 pCi/L52.3%+0.8 points
2007 to 20164,97570.4%6.8 pCi/L649.0 pCi/L52.8%Level
2006 to 20154,86570.4%7.0 pCi/L649.0 pCi/L52.9%−0.5 points
2005 to 20144,08870.9%7.3 pCi/L649.0 pCi/L52.4%First on file

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

Licking County, Geology

The ground under Licking County

Predicted

USGS's geologic map puts all of Licking County's mapped land in one class: high radon potential. The map puts 73.9% of Licking County in the area it calls Till Plains and 22.0% in Glaciated Plateau, with one smaller area beside them. USGS gives the first a radon index of 14 and the second 12, both in the high band (12 to 17).

USGS's geologic areas under Licking County
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Till PlainsGlacial deposits underlain by Ordovician through Devonian limestone and shale.High1473.9%
Glaciated PlateauPre-Wisconsin glacial deposits derived from high radioactivity marine black shale.High1222.0%
Area of Elevated RadioactivityPennsylvanian shale, sandstone, coal, and limestone.High124.1%

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

Licking County beside the ground around it

Licking County has more high-potential ground than Ohio as a whole: 100% of its land against 62.8%. Of the 7 counties that border it, none has as large a share of high-potential ground; Delaware County comes nearest at 100%.

Share of land by USGS radon potential: Licking County, the 7 counties bordering it and Ohio
AreaEPA zoneLow potentialModerate potentialHigh potential
Licking CountyZone 1NoneNone100%
Fairfield CountyZone 1NoneNone100%
Perry CountyZone 1None41.6%58.4%
Knox CountyZone 1NoneNone100%
Muskingum CountyZone 1None28.5%71.5%
Franklin CountyZone 1NoneNone100%
Delaware CountyZone 1NoneNone100%
Coshocton CountyZone 1NoneNone100%
Ohio88 counties, pooled by land areaVariesNone37.2%62.8%

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

Local help

Licking County, Local resources

Radon testing and mitigation in Licking County

Listed radon businesses with an address in Licking County:

Listed radon professionals by town: Newark, Reynoldsburg, Pataskala, New Albany, Granville, Johnstown, Alexandria

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

Licking County, Questions

Questions about radon in Licking County

Are radon levels high in Licking County?

Over the 2008 to 2017 laboratory totals, 71.2% of the radon tests reported to CDC for Licking County, Ohio were at or above 4 pCi/L, and the median reported pre-mitigation result was 7.0 pCi/L. Of 79 Ohio counties with 30 or more tests for the same period, 6 reported a higher share; pooled, the state comes to 52.3%.

Which counties border Licking County?

Licking County borders 7 counties: Fairfield County, Perry County, Knox County, Muskingum County, Franklin County, Delaware County and Coshocton County.

Products

Licking County, Products

Testing a home in Licking County

In Licking County, 71.2% of 4,694 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 Licking 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

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

Explore

Licking County, Bordering counties

Counties bordering Licking County

Calculated by Radon411

Licking County, Cities and towns

Cities and towns in Licking County

The Census Bureau estimates 185,564 residents in Licking County for July 1, 2025, 6,778 more than in 2020 (+3.8%). That works out to 272 people per square mile of land. Its largest town, Newark, has 51,473 residents, 27.7% of the total. Testing is reported here more often than across the state: CDC's 4,694 reported tests for 2008 to 2017 come to 25.3 for every 1,000 residents (2025 estimate), against 8.3 for Ohio.

From Newark to Gratiot, CDC publishes no figure by town: each reads Licking County's.

The 12 largest cities and towns in Licking County by residents, July 1, 2025
PlaceResidentsSince 2020Share of residents
Newark51,473+2.9%27.7%
Reynoldsburgextends beyond Licking County43,350+5.6%Counted whole
Pataskala18,529+3.5%10.0%
New Albanyextends beyond Licking County11,803+5.5%Counted whole
Heath10,859+3.7%5.9%
Granville6,252+4.8%3.4%
Johnstown5,476+5.0%3.0%
Buckeye Lakeextends beyond Licking County2,590+2.5%Counted whole
Hebron2,405+3.4%1.3%
Uticaextends beyond Licking County2,138+3.2%Counted whole
Hanover1,397+9.8%0.8%
Alexandria501+3.1%0.3%
  • Kirkersville
  • Hartford (Croton)
  • St. Louisville
  • Gratiot (part)

16 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. “(part)” marks a place that extends into another county. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond Licking County is counted whole, so it has no share.

Licking County, Homes

Homes in Licking County

Licking County is a place of houses on their own lots: 76% of its 73,021 homes are detached single-family houses, against 69% across Ohio. Much of Licking County is recent building: 23% of its homes have gone up since 2000 and the middle year built is 1978, against 1970 for Ohio. 74% of occupied homes are lived in by their owner (Ohio: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Licking County, Ohio, 2019 to 2023
HomesLicking CountyOhio
Housing units73,0215,271,573
Detached houses76%69%
In buildings of 5 or more9%15%
Mobile homes4%4%
Built before 196028%38%
Built since 200023%16%
Middle year built19781970
Owner-occupied74%67%

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