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 Champaign County, Ohio
EPA puts Champaign County in Zone 1, its highest radon zone, and high results are common there: 71.1% of the 596 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
Share at 4+ pCi/L
71.1%
18.8 pts above OH
- Champaign
- 71.1%
- Ohio
- 52.3%
596 tests, 2008 to 2017
Median result
6.8pCi/L
Action level reached
- Champaign
- 6.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
596
35th of 79 by tests
- Champaign
- 596
- Franklin
- 16,142
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Ohio
9 of 79
Top quarter
- Champaign
- 71.1%
- Pickaway
- 81.4%
By share, of 79 with 30+ tests
Read a result for Champaign County
Starts at Champaign County's median, 6.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 6.8 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. Champaign County's median reported result, 2008 to 2017.
The data
Champaign County, At a glance
Champaign County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Champaign County in
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 Champaign County, 2008 to 2017, laboratory
Under 2 pCi/L: 12%2 to 4 pCi/L: 17%4 pCi/L and above: 71%
Of 596 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 72 | 12.1% |
| 2 to 4 pCi/L | 100 | 16.8% |
| 4 pCi/L and above | 424 | 71.1% |
What these figures count
These are the 596 tests reported to CDC for Champaign 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).
Champaign County, Compared
Champaign County radon figures, compared
Calculated by Radon411More than half: 71.1% of the 596 radon tests reported to CDC for Champaign County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 9th of 79 Ohio counties with 30 or more tests for the same period. That is 18.8 points above the 52.3% pooled from 88 Ohio counties.
The median result, 6.8 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 135.2 pCi/L. The rest split 12.1% under 2 pCi/L and 16.8% from 2 to 4 (Ohio: 23.1% and 24.6%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 71.1% share point the same way here.
1 of its 6 bordering counties with figures ran higher, led by Logan County at 73.6%; Clark County reported 57.5%. 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 Champaign County went from 600 tests (2005 to 2014) to 596 (2008 to 2017), the share going from 68.3% to 71.1%.
Nationally, every county with a figure for the same period pools to 35.7%; Champaign County sits 35.4 points above it. CDC also counts 19 tests taken after mitigation in Champaign County for the same period: tests in homes where a fix was already in.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Champaign County, Geology
The ground under Champaign County
PredictedUSGS's geologic map puts all of Champaign County's mapped land in one class: high radon potential. All of it lies in the area the map calls Till Plains, to which USGS gives a radon index of 14, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Till Plains | Glacial deposits underlain by Ordovician through Devonian limestone and shale. | High | 14 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Champaign County beside the ground around it
Champaign County has more high-potential ground than Ohio as a whole: 100% of its land against 62.8%. Of the 6 counties that border it, none has as large a share of high-potential ground; Clark County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Champaign County, Local resources
Radon testing and mitigation in Champaign 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
Champaign County, Questions
Questions about radon in Champaign County
Are radon levels high in Champaign County?
Over the 2008 to 2017 laboratory totals, 71.1% of the radon tests reported to CDC for Champaign County, Ohio were at or above 4 pCi/L, and the median reported pre-mitigation result was 6.8 pCi/L. Of 79 Ohio counties with 30 or more tests for the same period, 8 reported a higher share; pooled, the state comes to 52.3%.
Which counties border Champaign County?
Champaign County borders 6 counties: Clark County, Logan County, Union County, Miami County, Shelby County and Madison County.
Products
Champaign County, Products
Testing a home in Champaign County
In Champaign County, 71.1% of 596 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 Champaign 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
Corentium Home battery digital radon detector
- C-NRPP 2024/25: Approved
- Battery
- Screen
Method: Alpha spectrometry
Short-term kit
RA400 short-term liquid scintillation radon test kit, lab fee included
- Lab fee included
Method: Liquid scintillation
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Champaign County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Champaign County
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Champaign County, Bordering counties
Counties bordering Champaign County
Calculated by Radon411- Radon levels in Logan CountyEPA zone 1
73.6%at or above 4 pCi/L
Median 7.9 pCi/L · 755 tests · 2.5 points above Champaign County
- Radon levels in Madison CountyEPA zone 1
67.4%at or above 4 pCi/L
Median 5.7 pCi/L · 549 tests · 3.7 points below Champaign County
- Radon levels in Miami CountyEPA zone 1
65.2%at or above 4 pCi/L
Median 6.1 pCi/L · 690 tests · 5.9 points below Champaign County
- Radon levels in Union CountyEPA zone 1
60.2%at or above 4 pCi/L
Median 4.8 pCi/L · 1,285 tests · 10.9 points below Champaign County
- Radon levels in Shelby CountyEPA zone 1
60.1%at or above 4 pCi/L
Median 5.2 pCi/L · 248 tests · 11.0 points below Champaign County
- Radon levels in Clark CountyEPA zone 1
57.5%at or above 4 pCi/L
Median 4.9 pCi/L · 1,447 tests · 13.6 points below Champaign County
Champaign County, Cities and towns
Cities and towns in Champaign County
Champaign County's population has barely moved since 2020: 38,820 residents on July 1, 2025 against 38,741 then, by the Census Bureau's estimates. That works out to 90 people per square mile of land. Its largest town, Urbana, has 11,140 residents, 28.7% of the total. Together its 7 incorporated places hold 44.5% of those residents; the other 55.5% live outside any of them. Testing is reported here more often than across the state: CDC's 596 reported tests for 2008 to 2017 come to 15.4 for every 1,000 residents (2025 estimate), against 8.3 for Ohio.
From Urbana to Mutual, CDC publishes no figure by town: each reads Champaign County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Urbana | 11,140 | −0.4% | 28.7% |
| St. Paris | 1,884 | −0.1% | 4.9% |
| Mechanicsburg | 1,681 | +0.2% | 4.3% |
| North Lewisburg | 1,657 | +0.9% | 4.3% |
| Christiansburg | 503 | −1.0% | 1.3% |
| Woodstock | 284 | −1.0% | 0.7% |
| Mutual | 127 | Level | 0.3% |
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).
Champaign County, Homes
Homes in Champaign County
Champaign County is a place of houses on their own lots: 80% of its 16,904 homes are detached single-family houses, against 69% across Ohio. Half of its homes were built before 1968, close to Ohio's 1970: 43% date from before 1960 and 12% from 2000 or later. Owners live in 77% of the occupied homes (Ohio: 67%), so for most households a test and a fix are their own to order.
| Homes | Champaign County | Ohio |
|---|---|---|
| Housing units | 16,904 | 5,271,573 |
| Detached houses | 80% | 69% |
| In buildings of 5 or more | 4% | 15% |
| Mobile homes | 6% | 4% |
| Built before 1960 | 43% | 38% |
| Built since 2000 | 12% | 16% |
| Middle year built | 1968 | 1970 |
| Owner-occupied | 77% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.