Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Adams County, Ohio
EPA puts Adams County in Zone 1, its highest radon zone, and only 18 radon tests from it are on file with CDC (2008 to 2017, laboratory totals). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
56.7%
Highland County
- Highland
- 56.7%
- Mason
- 25.0%
5 of 6 neighbours have 30+ tests, 2008 to 2017
Nearest county
47.1%
Brown County, 22 miles
- Brown
- 47.1%
- Ohio
- 52.3%
Share at 4+ pCi/L, 70 tests, 2008 to 2017
Ground above low
100.0%
0.1 pts above Ohio
- Adams
- 100.0%
- Ohio
- 99.9%
Share of land USGS rates moderate or high potential
Tests reported
18
Too few for a share
- Adams
- 18
- Needed
- 30
2008 to 2017, laboratory
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Read a result for Adams County
Starts at EPA's action level
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
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 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.
The data
Adams County, At a glance
Adams County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Adams County in
USGS geologic potential: High across 58% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Adams County, 2008 to 2017, laboratory
CDC holds 18 reported tests for Adams County over the 2008 to 2017 laboratory totals, with a median of 3.8 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Adams County beside the counties around it is how this page reads it.
What these figures count
Only 18 tests were reported to CDC for Adams County over 2008 to 2017 (laboratory totals), and tests are often run on homes being sold or already suspected of a problem: so few describe neither the county nor this house.
Measured: CDC tracking data. Figure above: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Adams County, Compared
Adams County radon figures, compared
Calculated by Radon411CDC's largest figure for Adams County rests on 18 tests over the 2008 to 2017 laboratory totals, 9 of them at or above 4 pCi/L, so each test moves its share by 5.6 points and no rank or comparison is drawn from it. Results reached as high as 45.8 pCi/L, with a middle value of 3.8 pCi/L.
Of the counties bordering it, 5 have a figure over the 2008 to 2017 laboratory totals: Highland County reported the largest share at or above 4 pCi/L, 56.7%, and Mason County, KY the smallest, 25.0%, with Pike County at 56.1%, Brown County at 47.1% and Scioto County at 37.0% between. Farther out, Clermont County (39 miles away) at 50.0%, Ross County (41 miles away) at 67.1% and Clinton County (43 miles away) at 52.4% have figures too. Pooled across 88 Ohio counties, 52.3% of reported tests reached that level; across every county in the country with a figure, 35.7%.
Statewide for the same period, Pickaway County reported the highest share (81.4%) and Cuyahoga County the lowest (21.7%). EPA's 1993 map puts Adams County in Zone 1, the map's highest label: a predicted county average above 4 pCi/L. USGS geology rates 58% of the county's land high radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Adams County, Geology
The ground under Adams County
PredictedUSGS's geologic map splits Adams County: 58.3% of its land is high radon potential and 41.7% moderate. The map puts 53.0% of Adams County in the area it calls Ohio Shale and 41.7% in Till Plains, with one smaller area beside them. USGS gives the first a radon index of 14, in the high band (12 to 17), and the second 11, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Ohio Shale | Devonian-Mississippian black shale (includes some Ordovician limestone) | High | 14 | 53.0% |
| Till Plains | Ordovician shale and limestone; glacial till. | Moderate | 11 | 41.7% |
| Mississippian Limestone | Mississippian limestone exhibiting high gamma radioactivity. | High | 14 | 5.3% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Adams County beside the ground around it
On high-potential ground Adams County is close to Ohio as a whole: 58.3% of its land against 62.8%. Of the 6 counties that border it, 2 have more high-potential ground, Pike County the most at 98.5%.
The map rates the ground, not the air in any home.
Local help
Adams County, Local resources
Radon testing and mitigation in Adams County
- Radon Education and Licensing ProgramRadon Education and Licensing Program, run by Ohio Department of Health, licenses or certifies radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Ohio.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
Free radon test kits are available for Ohio homeowners.
- Compare kits
- Professionals in Ohio479 professionals are listed in Ohio.
What Ohio's program says
- Phone
- 614-728-0272
- 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
Adams County, Questions
Questions about radon in Adams County
Are radon levels high in Adams County?
Over the 2008 to 2017 laboratory totals, 50.0% of the radon tests reported to CDC for Adams County, Ohio were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.8 pCi/L. Of the counties bordering it, 5 have a figure over the 2008 to 2017 laboratory totals: Highland County reported the largest share at or above 4 pCi/L, 56.7%, and Mason County, KY the smallest, 25.0%, with Pike County at 56.1%, Brown County at 47.1% and Scioto County at 37.0% between.
Which counties border Adams County?
Adams County borders 6 counties: Brown County, OH, Mason County, KY, Lewis County, KY, Highland County, OH, Pike County, OH and Scioto County, OH.
Products
Adams County, Products
Testing a home in Adams County
No CDC figure names Adams County; the nearest county with one, Brown County (22 miles away), reported 47.1% of its tests at or above 4 pCi/L over the 2008 to 2017 laboratory totals, the only reading nearby until a test of this home. In Zone 1 the year-round level in Adams 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
Monitor
Wave Plus battery radon and air quality monitor
- C-NRPP 2024/25: Not included
- Battery
- Bluetooth
- App only
Method: Alpha spectrometry
Short-term kitempowerDX
Standard Radon Test short-term mail-in radon test kit
- Lab fee included
Method: Passive sampler
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Adams County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Adams County
Explore
Adams County, Bordering counties
Counties bordering Adams County
Calculated by Radon411- Radon levels in Highland County, OHEPA zone 2
56.7%at or above 4 pCi/L
Median 4.8 pCi/L · 67 tests
- Radon levels in Pike County, OHEPA zone 1
56.1%at or above 4 pCi/L
Median 4.5 pCi/L · 57 tests
- Radon levels in Brown County, OHEPA zone 2
47.1%at or above 4 pCi/L
Median 3.3 pCi/L · 70 tests
- Radon levels in Scioto County, OHEPA zone 2
37.0%at or above 4 pCi/L
Median 2.7 pCi/L · 73 tests
- Radon levels in Lewis County, KYEPA zone 2
33.3%at or above 4 pCi/L
Median 2.8 pCi/L · 12 tests
- Radon levels in Mason County, KYEPA zone 2
25.0%at or above 4 pCi/L
Median 2.6 pCi/L · 32 tests
Adams County, Cities and towns
Cities and towns in Adams County
The Census Bureau estimates 27,865 residents in Adams County for July 1, 2025, 414 more than in 2020 (+1.5%). That works out to 48 people per square mile of land. No town dominates: West Union, the largest, has 3,091 residents, 11.1% of the total. Reported testing is thin here: 18 tests over 2008 to 2017, or 0.6 for every 1,000 residents (2025 estimate), where Ohio as a whole comes to 8.3.
From West Union to Rome (Stout), CDC publishes no figure by town: each reads Adams County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| West Union | 3,091 | +2.9% | 11.1% |
| Manchester | 1,874 | +1.7% | 6.7% |
| Peebles | 1,777 | +0.2% | 6.4% |
| Winchester | 998 | +1.9% | 3.6% |
| Seaman | 988 | +1.6% | 3.5% |
- Rome (Stout)
6 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).
Adams County, Homes
Homes in Adams County
Of Adams County's 12,737 homes, 70% are detached houses, against 69% across Ohio; 22% are mobile homes. Much of Adams County is recent building: 22% of its homes have gone up since 2000 and the middle year built is 1982, against 1970 for Ohio. 71% 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 | Adams County | Ohio |
|---|---|---|
| Housing units | 12,737 | 5,271,573 |
| Detached houses | 70% | 69% |
| In buildings of 5 or more | 4% | 15% |
| Mobile homes | 22% | 4% |
| Built before 1960 | 28% | 38% |
| Built since 2000 | 22% | 16% |
| Middle year built | 1982 | 1970 |
| Owner-occupied | 71% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.