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
Locations and reports
Radon Levels in Brown County, Minnesota
EPA puts Brown County in Zone 1, its highest radon zone, and high results are common there: 63.5% of the 115 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
63.5%
28.9 pts above MN
- Brown
- 63.5%
- Minnesota
- 34.6%
115 tests, 2023
Median result
5.4pCi/L
Action level reached
- Brown
- 5.4 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
115
28th of 62 by tests
- Brown
- 115
- Hennepin
- 6,545
Reported to CDC before any fix, 2023
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Minnesota
8 of 62
Top quarter
- Brown
- 63.5%
- Renville
- 75.7%
By share, of 62 with 30+ tests
Read a result for Brown County
Starts at Brown County's median, 5.4 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 5.4 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. Brown County's median reported result, 2023.
The data
Brown County, At a glance
Brown County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Brown 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 Brown County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 74.1% |
| 2015 | 70.9% |
| 2016 | 70.3% |
| 2017 | 66.9% |
| 2018 | 57.9% |
| 2019 | 55.6% |
| 2020 | 56.3% |
| 2021 | 53.5% |
| 2022 | 58.2% |
| 2023 | 63.5% |
2023: 63.5%. Across these years the share ran from 53.5% to 74.1%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 115 tests reported to CDC for Brown 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).
Brown County, Compared
Brown County radon figures, compared
Calculated by Radon411More than half: 63.5% of the 115 radon tests reported to CDC for Brown County in 2023 read at least 4 pCi/L. That places it 8th of 62 Minnesota counties with 30 or more tests for the same period. That is 28.9 points above the 34.6% pooled from 86 Minnesota counties.
The median result, 5.4 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 54.4 pCi/L. The rest split 19.1% under 2 pCi/L and 17.4% from 2 to 4 (Minnesota: 36.6% and 28.9%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 63.5% share point the same way here.
1 of its 4 bordering counties with figures ran higher, led by Renville County at 75.7%; Blue Earth County reported 32.7%. Statewide for the same period, Renville County reported the highest share (75.7%) and Lake County the lowest (3.8%).
The busiest year on file was 2014, with 344 tests reported; the quietest, 2019, had 81.
Over 10 years of annual figures the share fell 10.6 points, from 74.1% in 2014 to 63.5% in 2023; its peak was 74.1% in 2014. Nationally, every county with a figure for the same period pools to 33.4%; Brown County sits 30.1 points above it.
Brown CountyMinnesota, pooled
63.5% % of tests34.6% % of tests
| Year | Tests | Brown County, at or above 4 pCi/L | Minnesota, pooled |
|---|---|---|---|
| 2014 | 344 | 74.1% | 42.9% |
| 2015 | 289 | 70.9% | 43.6% |
| 2016 | 229 | 70.3% | 37.0% |
| 2017 | 121 | 66.9% | 38.2% |
| 2018 | 126 | 57.9% | 38.3% |
| 2019 | 81 | 55.6% | 36.1% |
| 2020 | 192 | 56.3% | 31.8% |
| 2021 | 142 | 53.5% | 33.1% |
| 2022 | 110 | 58.2% | 31.6% |
| 2023 | 115 | 63.5% | 34.6% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Brown County, State data
Minnesota's own radon test data
MeasuredWhat Minnesota's own agencies publish about radon tests in Brown County, with their period. These are not CDC's figures and are never added to them.
MeasuredState figures, not CDC's
What the Minnesota Department of Health reports for Brown County
Radon Testing (MN Public Health Data Access Portal): home radon tests reported voluntarily by private laboratories and licensed radon measurement professionals, counted by property. Period: 2016-2025.
Share with one or more tests at or above 4 pCi/L
62.4%
738 properties tested with one or more tests at or above 4 pCi/L
Median result
4.9 pCi/L
Average result
6.2 pCi/L
Tests behind these figures
118 properties tested a year on average
- MDH says these data do not include all of the radon tests conducted in Minnesota.
- Post-mitigation tests are excluded from the averages and the median; the percentages use each property's highest test.
- Each home is unique and can have very different results than a neighbor's home; the only way to know is to test.
- These figures describe tests reported to the Minnesota Department of Health in this area. They count a different set of tests than CDC's figures and are not a reading of any one home.
Measured: Minnesota Department of Health data, 2016-2025.
Brown County, Geology
The ground under Brown County
PredictedUSGS's geologic map puts all of Brown County's mapped land in one class: high radon potential. All of it lies in the area the map calls Central Lowland-Till Prairie, 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 |
|---|---|---|---|---|
| Central Lowland-Till Prairie | Silty and clayey till derived from shale and sandstone. | High | 14 | 99.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Brown County beside the ground around it
Brown County has more high-potential ground than Minnesota as a whole: 100% of its land against 61.1%. Of the 6 counties that border it, none has as large a share of high-potential ground; Blue Earth County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Brown County, Local resources
Radon testing and mitigation in Brown County
- MDH Indoor Air UnitMDH Indoor Air Unit, run by MN Dept. of Health, licenses or certifies radon professionals and states the rule for disclosing radon when a home is sold, and answers questions about testing and mitigation in Minnesota.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- Professionals in Minnesota255 professionals are listed in Minnesota.
What Minnesota's program says
- Phone
- 651-201-4601
- health.indoorair@state.mn.us
- Licensing of radon professionals
The Radon Licensing Act requires anyone who performs a radon test or radon mitigation, in a building they do not own or lease, must be licensed by MDH.
- Disclosure when a home is sold or rented
The Minnesota Radon Awareness Act requires specific disclosure and education be provided to potential home buyers during residential real estate transactions in Minnesota.
What it means
Brown County, Questions
Questions about radon in Brown County
Are radon levels high in Brown County?
In 2023, 63.5% of the radon tests reported to CDC for Brown County, Minnesota were at or above 4 pCi/L, and the median reported pre-mitigation result was 5.4 pCi/L. Of 62 Minnesota counties with 30 or more tests for the same period, 7 reported a higher share; pooled, the state comes to 34.6%.
Which counties border Brown County?
Brown County borders 6 counties: Nicollet County, Watonwan County, Redwood County, Renville County, Cottonwood County and Blue Earth County.
Products
Brown County, Products
Testing a home in Brown County
In Brown County, 63.5% of 115 tests reported to CDC in 2023 reached 4 pCi/L, against 34.6% pooled across Minnesota. In Zone 1 the year-round level in Brown 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
MonitorAEGTEST
HOUND-3786 rechargeable radon monitor with a 3.5-inch color screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Ion chamber
First reading: Within 10 minutes
Short-term kitFirst Alert
RD1 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 2 to 4 days
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Brown County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Brown County
Explore
Brown County, Bordering counties
Counties bordering Brown County
Calculated by Radon411- Radon levels in Renville CountyEPA zone 1
75.7%at or above 4 pCi/L
Median 6.3 pCi/L · 37 tests · 12.2 points above Brown County
- Radon levels in Watonwan CountyEPA zone 1
66.7%at or above 4 pCi/L
Median 6.2 pCi/L · 24 tests · 3.2 points above Brown County
- Radon levels in Redwood CountyEPA zone 1
54.8%at or above 4 pCi/L
Median 4.6 pCi/L · 31 tests · 8.7 points below Brown County
- Radon levels in Cottonwood CountyEPA zone 1
50.0%at or above 4 pCi/L
Median 3.5 pCi/L · 12 tests · 13.5 points below Brown County
- Radon levels in Nicollet CountyEPA zone 1
45.7%at or above 4 pCi/L
Median 3.7 pCi/L · 129 tests · 17.8 points below Brown County
- Radon levels in Blue Earth CountyEPA zone 1
32.7%at or above 4 pCi/L
Median 2.2 pCi/L · 392 tests · 30.8 points below Brown County
Brown County, Cities and towns
Cities and towns in Brown County
About 25,517 people live in Brown County by the Census Bureau's estimate for July 1, 2025, 391 fewer than in 2020 (−1.5%). That works out to 42 people per square mile of land. New Ulm alone is home to 13,863 of them, 54.3% of the total. CDC's 115 reported tests for 2023 work out to 4.5 per 1,000 residents (2025 estimate), close to Minnesota's 3.9.
From New Ulm to Cobden, CDC publishes no figure by town: each reads Brown County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| New Ulm | 13,863 | −1.9% | 54.3% |
| Sleepy Eye | 3,461 | +0.5% | 13.6% |
| Springfield | 1,980 | −2.4% | 7.8% |
| Hanska | 378 | −1.8% | 1.5% |
| Comfreyextends beyond Brown County | 375 | −2.6% | Counted whole |
| Evan | 70 | −2.8% | 0.3% |
| Cobden | 32 | −3.0% | 0.1% |
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). A place that extends beyond Brown County is counted whole, so it has no share.
Brown County, Homes
Homes in Brown County
Brown County is a place of houses on their own lots: 80% of its 11,802 homes are detached single-family houses, against 66% across Minnesota. The homes are older than Minnesota's as a whole: half were built before 1961 (1978 for Minnesota), and 49% date from before 1960. Owners live in 79% of the occupied homes (Minnesota: 72%), so for most households a test and a fix are their own to order.
| Homes | Brown County | Minnesota |
|---|---|---|
| Housing units | 11,802 | 2,519,538 |
| Detached houses | 80% | 66% |
| In buildings of 5 or more | 10% | 19% |
| Mobile homes | 3% | 3% |
| Built before 1960 | 49% | 29% |
| Built since 2000 | 13% | 22% |
| Middle year built | 1961 | 1978 |
| Owner-occupied | 79% | 72% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.