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 Norman County, Minnesota
EPA puts Norman County in Zone 1, its highest radon zone, and only 8 radon tests from it are on file with CDC (2023). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
58.4%
15.0 pts above MN
- Norman
- 58.4%
- Minnesota
- 43.4%
154 tests, 2008 to 2017
Median result
4.8pCi/L
Action level reached
- Norman
- 4.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
154
73rd of 85 by tests
- Norman
- 154
- Hennepin
- 35,213
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 Minnesota
39 of 85
Middle half
- Norman
- 58.4%
- Rock
- 83.8%
By share, of 85 with 30+ tests
Read a result for Norman County
Starts at Norman County's median, 4.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.8 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. Norman County's median reported result, 2008 to 2017.
The data
Norman County, At a glance
Norman County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Norman 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 Norman County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 44.4% |
| 2015 | 50.0% |
| 2016 | 63.6% |
| 2017 | 51.9% |
| 2018 | 54.0% |
| 2019 | 66.7% |
| 2020 | 45.5% |
| 2021 | 28.0% |
| 2022 | 55.0% |
| 2023 | 37.5% |
2023: 37.5%. Across these years the share ran from 28.0% to 66.7%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 8 tests were reported to CDC for Norman County over 2023, 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: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Norman County, Compared
Norman County radon figures, compared
Calculated by Radon411More than half: 58.4% of the 154 radon tests reported to CDC for Norman County over the 2008 to 2017 laboratory totals read at least 4 pCi/L. That places it 39th of 85 Minnesota counties with 30 or more tests for the same period. That is 15.0 points above the 43.4% pooled from 87 Minnesota counties.
The newest figure, in 2023, counts only 8 tests (37.5% at or above 4 pCi/L), too few to compare, so this reading uses the 154-test figure.
The median result, 4.8 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 23.1 pCi/L. The rest split 17.5% under 2 pCi/L and 24.0% from 2 to 4 (Minnesota: 27.4% and 29.2%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 58.4% share point the same way here.
3 of its 6 bordering counties with figures ran higher, led by Polk County at 70.8%; Becker County reported 51.4%. Statewide for the same period, Rock County reported the highest share (83.8%) and Anoka County the lowest (17.4%).
The busiest year on file was 2018, with 63 tests reported; the quietest, 2019, had 6.
Nationally, every county with a figure for the same period pools to 35.7%; Norman County sits 22.7 points above it. CDC also counts 8 tests taken after mitigation in Norman 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.
Norman County, State data
Minnesota's own radon test data
MeasuredWhat Minnesota's own agencies publish about radon tests in Norman 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 Norman 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
57.9%
88 properties tested with one or more tests at or above 4 pCi/L
Median result
4.4 pCi/L
Average result
6.0 pCi/L
Tests behind these figures
15 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.
Norman County, Geology
The ground under Norman County
PredictedUSGS's geologic map puts all of Norman County's mapped land in one class: high radon potential. The map puts 87.7% of Norman County in the area it calls Lake Agassiz Plain and 12.2% in Central Lowland-Till Prairie. USGS gives the first a radon index of 15 and the second 14, both in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Lake Agassiz Plain | Silt and clay deposits of Glacial Lake Agassiz derived from Cretaceous shales containing higher than average amounts of uranium. | High | 15 | 87.7% |
| Central Lowland-Till Prairie | Silty and clayey till derived from shale and sandstone. | High | 14 | 12.2% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Norman County beside the ground around it
Norman 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; Becker County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Norman County, Local resources
Radon testing and mitigation in Norman 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
Norman County, Questions
Questions about radon in Norman County
Are radon levels high in Norman County?
In 2023, 37.5% of the radon tests reported to CDC for Norman County, Minnesota were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.0 pCi/L. Of 85 Minnesota counties with 30 or more tests for the same period, 38 reported a higher share; pooled, the state comes to 43.4%.
Which counties border Norman County?
Norman County borders 6 counties: Clay County, MN, Mahnomen County, MN, Traill County, ND, Polk County, MN, Cass County, ND and Becker County, MN.
Products
Norman County, Products
Testing a home in Norman County
In Norman County, 58.4% of 154 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 43.4% pooled across Minnesota. In Zone 1 the year-round level in Norman 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-1011S rechargeable radon detector with a screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 12 hours
Short-term kit
PicoCan short-term charcoal canister radon test
- Lab fee included
Method: Charcoal
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Norman County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Norman County
Explore
Norman County, Bordering counties
Counties bordering Norman County
Calculated by Radon411- Radon levels in Polk County, MNEPA zone 1
70.8%at or above 4 pCi/L
Median 6.7 pCi/L · 397 tests · 12.4 points above Norman County
- Radon levels in Mahnomen County, MNEPA zone 1
62.5%at or above 4 pCi/L
Median 4.8 pCi/L · 48 tests · 4.1 points above Norman County
- Radon levels in Clay County, MNEPA zone 1
61.5%at or above 4 pCi/L
Median 5.6 pCi/L · 465 tests · 3.1 points above Norman County
- Radon levels in Cass County, NDEPA zone 1
57.5%at or above 4 pCi/L
Median 4.7 pCi/L · 862 tests · 0.9 points below Norman County
- Radon levels in Traill County, NDEPA zone 1
51.4%at or above 4 pCi/L
Median 4.1 pCi/L · 37 tests · 7.0 points below Norman County
- Radon levels in Becker County, MNEPA zone 1
51.4%at or above 4 pCi/L
Median 4.0 pCi/L · 313 tests · 7.0 points below Norman County
Norman County, Cities and towns
Cities and towns in Norman County
About 6,336 people live in Norman County by the Census Bureau's estimate for July 1, 2025, 102 fewer than in 2020 (−1.6%). Spread over its land, that is 7.3 people to the square mile. Its largest town, Ada, has 1,712 residents, 27.0% of the total. Together its 8 incorporated places hold 60.9% of those residents; the other 39.1% live outside any of them. CDC's 154 reported tests for 2008 to 2017 work out to 24.3 per 1,000 residents (2025 estimate), close to Minnesota's 22.5.
From Ada to Borup, CDC publishes no figure by town: each reads Norman County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Ada | 1,712 | −2.3% | 27.0% |
| Twin Valley | 702 | −2.5% | 11.1% |
| Halstad | 555 | −2.5% | 8.8% |
| Hendrum | 284 | −1.4% | 4.5% |
| Gary | 226 | Level | 3.6% |
| Shelly | 177 | −3.3% | 2.8% |
| Perley | 109 | −2.7% | 1.7% |
| Borup | 95 | Level | 1.5% |
8 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).
Norman County, Homes
Homes in Norman County
Norman County is a place of houses on their own lots: 84% of its 3,228 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 82% of the occupied homes (Minnesota: 72%), so for most households a test and a fix are their own to order.
| Homes | Norman County | Minnesota |
|---|---|---|
| Housing units | 3,228 | 2,519,538 |
| Detached houses | 84% | 66% |
| In buildings of 5 or more | 8% | 19% |
| Mobile homes | 5% | 3% |
| Built before 1960 | 49% | 29% |
| Built since 2000 | 10% | 22% |
| Middle year built | 1961 | 1978 |
| Owner-occupied | 82% | 72% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.