Short-term kit
PicoCan short-term charcoal canister radon test
- Lab fee included
Method: Charcoal
In home: 48 to 96 hours
Locations and reports
Radon Levels in Sheboygan County, Wisconsin
EPA puts Sheboygan County in Zone 2, its middle radon zone, and high results are common there: 42.9% of the 399 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
42.9%
7.2 pts above WI
- Sheboygan
- 42.9%
- Wisconsin
- 35.7%
399 tests, 2023
Median result
3.3pCi/L
Below action level
- Sheboygan
- 3.3 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
399
14th of 69 by tests
- Sheboygan
- 399
- 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
22 of 69
Middle half
- Sheboygan
- 42.9%
- Langlade
- 65.8%
By share, of 69 with 30+ tests
Read a result for Sheboygan County
Starts at Sheboygan County's median, 3.3 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 3.3 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. Sheboygan County's median reported result, 2023.
The data
Sheboygan County, At a glance
Sheboygan County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Sheboygan County is a
USGS geologic potential: Low across 52% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Sheboygan County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 55.2% |
| 2015 | 55.6% |
| 2016 | 39.0% |
| 2017 | 35.9% |
| 2019 | 34.3% |
| 2020 | 39.3% |
| 2021 | 30.5% |
| 2022 | 44.9% |
| 2023 | 42.9% |
2023: 42.9%. Across these years the share ran from 30.5% to 55.6%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 399 tests reported to CDC for Sheboygan 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).
Sheboygan County, Compared
Sheboygan County radon figures, compared
Calculated by Radon411In Sheboygan County, about 4 in 10 reported tests in 2023 (171 of 399) were at or above EPA's action level. Against the national pool of 33.4%, the gap is 9.5 points higher. Across 72 Wisconsin counties pooled together, 35.7% of tests reached that level, so Sheboygan County runs 7.2 points above its state.
Of 5 neighbours with a figure, 3 reported a larger share at or above 4 pCi/L and 2 a smaller one; the spread is 19.6% (Fond du Lac County) to 51.6% (Calumet County). By share, Sheboygan County is 22nd of 69 Wisconsin counties with 30 or more tests for the same period.
Year by year, 2014 opened at 55.2% and 2023 closed at 42.9% (down 12.3 points), with 2015 the high at 55.6%. Half the tests came in under 3.3 pCi/L and half over it; the single highest reached 67.6 pCi/L. Below the action level, 127 tests (31.8%) came in under 2 pCi/L, against 41.4% statewide, and 101 tests (25.3%) fell between 2 and 4, against 23.0% statewide.
Zone 2 on EPA's map (predicted average between 2 and 4 pCi/L) and a 42.9% share point the same way here. USGS geology rates 52% of the county's land low radon potential. CDC also counts 20 tests taken after mitigation in Sheboygan County for the same period: tests in homes where a fix was already in.
The busiest year on file was 2019, with 470 tests reported; the quietest, 2014, had 163.
Sheboygan CountyWisconsin, pooled
| Year | Tests | Sheboygan County, at or above 4 pCi/L | Wisconsin, pooled |
|---|---|---|---|
| 2014 | 163 | 55.2% | 51.1% |
| 2015 | 198 | 55.6% | 51.6% |
| 2016 | 372 | 39.0% | 45.2% |
| 2017 | 262 | 35.9% | 44.8% |
| 2019 | 470 | 34.3% | 42.9% |
| 2020 | 351 | 39.3% | 27.0% |
| 2021 | 318 | 30.5% | 39.9% |
| 2022 | 196 | 44.9% | 42.9% |
| 2023 | 399 | 42.9% | 35.7% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Sheboygan County, Geology
The ground under Sheboygan County
PredictedUSGS's geologic map splits Sheboygan County: 51.7% of its land is low radon potential and 47.9% high. The map puts 51.7% of Sheboygan County in the area it calls Eastern Ridges and Lowlands and 47.9% in Eastern Ridges and Lowlands. USGS gives the first a radon index of 8, in the low band (5 to 8), and the second 12, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Eastern Ridges and Lowlands | Glacial lake deposits, clayey glacial deposits. | Low | 8 | 51.7% |
| Eastern Ridges and Lowlands | Glacial deposits derived from Ordovician carbonate rocks. | High | 12 | 47.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Sheboygan County beside the ground around it
Sheboygan County has more high-potential ground than Wisconsin as a whole: 47.9% of its land against 34.8%. Of the 5 counties that border it, 2 have more high-potential ground, Washington County the most at 100%.
The map rates the ground, not the air in any home.
Local help
Sheboygan County, Local resources
Radon testing and mitigation in Sheboygan 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
Sheboygan County, Questions
Questions about radon in Sheboygan County
Are radon levels high in Sheboygan County?
In 2023, 42.9% of the radon tests reported to CDC for Sheboygan County, Wisconsin were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.3 pCi/L. Of 69 Wisconsin counties with 30 or more tests for the same period, 21 reported a higher share; pooled, the state comes to 35.7%.
Which counties border Sheboygan County?
Sheboygan County borders 5 counties: Ozaukee County, Manitowoc County, Washington County, Fond du Lac County and Calumet County.
Products
Sheboygan County, Products
Testing a home in Sheboygan County
In Sheboygan County, 42.9% of 399 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 Sheboygan 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
MonitorAranet
Radon Plus battery digital radon monitor with an e-ink screen
- C-NRPP 2024/25: Approved
- Battery
- Bluetooth
- Alarm
- Screen, app
Method: Ion chamber
First reading: Within 10 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Sheboygan County, Bordering counties
Counties bordering Sheboygan County
Calculated by Radon411- Radon levels in Calumet CountyEPA zone 2
51.6%at or above 4 pCi/L
Median 4.4 pCi/L · 122 tests · 8.7 points above Sheboygan County
- Radon levels in Washington CountyEPA zone 1
47.9%at or above 4 pCi/L
Median 3.8 pCi/L · 399 tests · 5.0 points above Sheboygan County
- Radon levels in Ozaukee CountyEPA zone 2
45.8%at or above 4 pCi/L
Median 3.6 pCi/L · 445 tests · 2.9 points above Sheboygan County
- Radon levels in Manitowoc CountyEPA zone 2
31.1%at or above 4 pCi/L
Median 2.2 pCi/L · 209 tests · 11.8 points below Sheboygan County
- Radon levels in Fond du Lac CountyEPA zone 1
19.6%at or above 4 pCi/L
Median 1.4 pCi/L · 984 tests · 23.3 points below Sheboygan County
Sheboygan County, Cities and towns
Cities and towns in Sheboygan County
Sheboygan County's population has barely moved since 2020: 118,047 residents on July 1, 2025 against 118,040 then, by the Census Bureau's estimates. That works out to 231 people per square mile of land. Its largest town, Sheboygan, has 49,376 residents, 41.8% of the total. Together its 13 incorporated places hold 69.8% of those residents; the other 30.2% live outside any of them. CDC's 399 reported tests for 2023 work out to 3.4 per 1,000 residents (2025 estimate), close to Wisconsin's 3.5.
From Sheboygan to Glenbeulah, CDC publishes no figure by town: each reads Sheboygan County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Sheboygan | 49,376 | −1.1% | 41.8% |
| Plymouth | 8,821 | −1.3% | 7.5% |
| Sheboygan Falls | 8,687 | +6.0% | 7.4% |
| Howards Grove | 3,190 | −1.6% | 2.7% |
| Oostburg | 3,056 | −0.2% | 2.6% |
| Kohler | 2,272 | +4.0% | 1.9% |
| Cedar Grove | 2,083 | −0.8% | 1.8% |
| Random Lake | 1,572 | +0.6% | 1.3% |
| Elkhart Lake | 1,190 | +25.7% | 1.0% |
| Cascade | 704 | −2.6% | 0.6% |
| Adell | 483 | −3.0% | 0.4% |
| Waldo | 480 | +3.0% | 0.4% |
- Glenbeulah
13 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).
Sheboygan County, Homes
Homes in Sheboygan County
Of Sheboygan County's 52,549 homes, 67% are detached houses, against 66% across Wisconsin; 14% are in buildings of five or more homes. Half of its homes were built before 1969, close to Wisconsin's 1975: 41% date from before 1960 and 16% from 2000 or later. 71% of occupied homes are lived in by their owner (Wisconsin: 68%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Sheboygan County | Wisconsin |
|---|---|---|
| Housing units | 52,549 | 2,750,750 |
| Detached houses | 67% | 66% |
| In buildings of 5 or more | 14% | 17% |
| Mobile homes | 2% | 3% |
| Built before 1960 | 41% | 34% |
| Built since 2000 | 16% | 20% |
| Middle year built | 1969 | 1975 |
| Owner-occupied | 71% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.