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
Locations and reports
Radon Levels in Oconto County, Wisconsin
EPA puts Oconto County in Zone 2, its middle radon zone, and high results are common there: 52.3% of the 130 radon tests reported to CDC (2023) 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
52.3%
16.6 pts above WI
- Oconto
- 52.3%
- Wisconsin
- 35.7%
130 tests, 2023
Median result
4.5pCi/L
Action level reached
- Oconto
- 4.5 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
130
39th of 69 by tests
- Oconto
- 130
- Dane
- 2,887
Reported to CDC before any fix, 2023
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in Wisconsin
8 of 69
Top quarter
- Oconto
- 52.3%
- Langlade
- 65.8%
By share, of 69 with 30+ tests
Read a result for Oconto County
Starts at Oconto County's median, 4.5 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.5 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. Oconto County's median reported result, 2023.
The data
Oconto County, At a glance
Oconto County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Oconto County is a
USGS geologic potential: Moderate across 67% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Oconto County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 48.5% |
| 2015 | 49.4% |
| 2016 | 38.7% |
| 2017 | 35.0% |
| 2019 | 40.7% |
| 2020 | 48.8% |
| 2021 | 39.6% |
| 2022 | 35.6% |
| 2023 | 52.3% |
2023: 52.3%. Across these years the share ran from 35.0% to 52.3%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 130 tests reported to CDC for Oconto County over 2023, 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: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Oconto County, Compared
Oconto County radon figures, compared
Calculated by Radon411More than half: 52.3% of the 130 radon tests reported to CDC for Oconto County in 2023 read at least 4 pCi/L. That places it 8th of 69 Wisconsin counties with 30 or more tests for the same period. That is 16.6 points above the 35.7% pooled from 72 Wisconsin counties.
The median result, 4.5 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 181.4 pCi/L. The rest split 26.9% under 2 pCi/L and 20.8% from 2 to 4 (Wisconsin: 41.4% and 23.0%). The reported tests do not follow EPA's Zone 2 label for Oconto County (predicted average between 2 and 4 pCi/L): 52.3% of them reached 4 pCi/L, fewer than that label suggests.
2 of its 5 bordering counties with figures ran higher, led by Langlade County at 65.8%; Brown County reported 23.0%. Statewide for the same period, Langlade County reported the highest share (65.8%) and Bayfield County the lowest (5.7%).
The busiest year on file was 2016, with 439 tests reported; the quietest, 2020, had 43.
Over 9 years of annual figures the share rose 3.8 points, from 48.5% in 2014 to 52.3% in 2023; its peak was 52.3% in 2023. Nationally, every county with a figure for the same period pools to 33.4%; Oconto County sits 18.9 points above it. CDC also counts 11 tests taken after mitigation in Oconto County for the same period: tests in homes where a fix was already in.
Oconto CountyWisconsin, pooled
52.3% % of tests35.7% % of tests
| Year | Tests | Oconto County, at or above 4 pCi/L | Wisconsin, pooled |
|---|---|---|---|
| 2014 | 66 | 48.5% | 51.1% |
| 2015 | 85 | 49.4% | 51.6% |
| 2016 | 439 | 38.7% | 45.2% |
| 2017 | 117 | 35.0% | 44.8% |
| 2019 | 54 | 40.7% | 42.9% |
| 2020 | 43 | 48.8% | 27.0% |
| 2021 | 53 | 39.6% | 39.9% |
| 2022 | 59 | 35.6% | 42.9% |
| 2023 | 130 | 52.3% | 35.7% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Oconto County, Geology
The ground under Oconto County
PredictedUSGS's geologic map splits Oconto County: 67.2% of its land is moderate radon potential and 32.6% high. The map puts 66.7% of Oconto County in the area it calls Green Bay Lobe and 32.6% in Wolf River Batholith, with one smaller area beside them. USGS gives the first a radon index of 10, in the moderate band (9 to 11), and the second 13, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Green Bay Lobe | Glacial deposits derived from carbonate and igneous rocks. | Moderate | 10 | 66.7% |
| Wolf River Batholith | Plutonic granitic rocks including quartz monzonite, syenite, monzonite, anorthosite. | High | 13 | 32.6% |
| Chippewa, Wisconsin Valley, and Langlade sublobes of the Superior Lobe | Granite, granite-derived glacial deposits, and mafic volcanic rocks. | Moderate | 10 | 0.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Oconto County beside the ground around it
On high-potential ground Oconto County is close to Wisconsin as a whole: 32.6% of its land against 34.8%. Of the 6 counties that border it, 3 have more high-potential ground, Menominee County the most at 98.0%.
The map rates the ground, not the air in any home.
Local help
Oconto County, Local resources
Radon testing and mitigation in Oconto County
- Wisconsin's radon programWisconsin Department of Health ServicesWisconsin's radon program does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Wisconsin.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
We recommend starting with your regional Radon Information Center since many centers provide test kits for free or reduced cost, and often with laboratory fees covered.
- Compare kits
- Professionals in Wisconsin19 professionals are listed in Wisconsin.
What Wisconsin's program says
- Phone
- 1-888-569-7236
- DHSRadon@dhs.wisconsin.gov
- Licensing of radon professionals
The State of Wisconsin does not require contractors performing radon measurement or mitigation work to be state licensed or nationally certified.
What it means
Oconto County, Questions
Questions about radon in Oconto County
Are radon levels high in Oconto County?
In 2023, 52.3% of the radon tests reported to CDC for Oconto County, Wisconsin were at or above 4 pCi/L, and the median reported pre-mitigation result was 4.5 pCi/L. Of 69 Wisconsin counties with 30 or more tests for the same period, 7 reported a higher share; pooled, the state comes to 35.7%.
Which counties border Oconto County?
Oconto County borders 6 counties: Menominee County, Marinette County, Shawano County, Langlade County, Brown County and Forest County.
Products
Oconto County, Products
Testing a home in Oconto County
In Oconto County, 52.3% of 130 tests reported to CDC in 2023 reached 4 pCi/L, against 35.7% pooled across Wisconsin. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Oconto County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
MonitorKidde
Radon Detector (RAB) battery digital radon detector with an alarm
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 12 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Oconto County, Bordering counties
Counties bordering Oconto County
Calculated by Radon411- Radon levels in Menominee CountyEPA zone 1
100.0%at or above 4 pCi/L
Median 11.0 pCi/L · 3 tests · 47.7 points above Oconto County
- Radon levels in Langlade CountyEPA zone 1
65.8%at or above 4 pCi/L
Median 6.0 pCi/L · 225 tests · 13.5 points above Oconto County
- Radon levels in Shawano CountyEPA zone 1
57.0%at or above 4 pCi/L
Median 5.0 pCi/L · 114 tests · 4.7 points above Oconto County
- Radon levels in Marinette CountyEPA zone 2
44.3%at or above 4 pCi/L
Median 2.6 pCi/L · 61 tests · 8.0 points below Oconto County
- Radon levels in Forest CountyEPA zone 2
40.0%at or above 4 pCi/L
Median 2.9 pCi/L · 45 tests · 12.3 points below Oconto County
- Radon levels in Brown CountyEPA zone 2
23.0%at or above 4 pCi/L
Median 1.4 pCi/L · 551 tests · 29.3 points below Oconto County
Oconto County, Cities and towns
Cities and towns in Oconto County
The Census Bureau estimates 40,195 residents in Oconto County for July 1, 2025, 1,118 more than in 2020 (+2.9%). That works out to 40 people per square mile of land. No town dominates: Oconto, the largest, has 4,640 residents, 11.5% of the total. CDC's 130 reported tests for 2023 work out to 3.2 per 1,000 residents (2025 estimate), close to Wisconsin's 3.5.
From Oconto to Suring, CDC publishes no figure by town: each reads Oconto County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Oconto | 4,640 | +0.4% | 11.5% |
| Pulaskiextends beyond Oconto County | 4,048 | +4.4% | Counted whole |
| Oconto Falls | 3,012 | +1.5% | 7.5% |
| Gillett | 1,276 | −1.5% | 3.2% |
| Lena | 631 | +18.6% | 1.6% |
| Suring | 508 | −0.6% | 1.3% |
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). A place that extends beyond Oconto County is counted whole, so it has no share.
Oconto County, Homes
Homes in Oconto County
Oconto County is a place of houses on their own lots: 82% of its 23,998 homes are detached single-family houses, against 66% across Wisconsin. Half of its homes were built before 1981, close to Wisconsin's 1975: 26% date from before 1960 and 24% from 2000 or later. Owners live in 85% of the occupied homes (Wisconsin: 68%), so for most households a test and a fix are their own to order.
| Homes | Oconto County | Wisconsin |
|---|---|---|
| Housing units | 23,998 | 2,750,750 |
| Detached houses | 82% | 66% |
| In buildings of 5 or more | 4% | 17% |
| Mobile homes | 11% | 3% |
| Built before 1960 | 26% | 34% |
| Built since 2000 | 24% | 20% |
| Middle year built | 1981 | 1975 |
| Owner-occupied | 85% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.