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 Roosevelt County, Montana
EPA puts Roosevelt County in Zone 1, its highest radon zone, and only 16 radon tests from it are on file with CDC (2008 to 2017, laboratory totals). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
75.7%
Sheridan County
- Sheridan
- 75.7%
- Williams
- 35.4%
5 of 7 neighbours have 30+ tests, 2006 to 2015
Nearest county
75.7%
Sheridan County, 38 miles
- Sheridan
- 75.7%
- Montana
- 47.4%
Share at 4+ pCi/L, 70 tests, 2006 to 2015
Ground above low
100.0%
Level with Montana
- Roosevelt
- 100.0%
- Montana
- 100.0%
Share of land USGS rates moderate or high potential
Tests reported
17
Too few for a share
- Roosevelt
- 17
- Needed
- 30
2007 to 2016, laboratory
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Read a result for Roosevelt County
Starts at EPA's action level
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.0 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.
The data
Roosevelt County, At a glance
Roosevelt County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Roosevelt 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 Roosevelt County, 2008 to 2017, laboratory
CDC holds 16 reported tests for Roosevelt County over the 2008 to 2017 laboratory totals, with a median of 8.7 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Roosevelt County beside the counties around it is how this page reads it.
What these figures count
Only 16 tests were reported to CDC for Roosevelt County over 2008 to 2017 (laboratory totals), 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: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Roosevelt County, Compared
Roosevelt County radon figures, compared
Calculated by Radon411CDC's largest figure for Roosevelt County rests on 17 tests over the 2007 to 2016 laboratory totals, 16 of them at or above 4 pCi/L, so each test moves its share by 5.9 points and no rank or comparison is drawn from it. Results reached as high as 35.1 pCi/L, with a middle value of 9.0 pCi/L.
Of the counties bordering it, 5 have a figure over the 2006 to 2015 laboratory totals: Sheridan County reported the largest share at or above 4 pCi/L, 75.7%, and Williams County, ND the smallest, 35.4%, with Richland County at 75.0%, McKenzie County, ND at 65.2% and Valley County at 50.0% between. Farther out, Dawson County (71 miles away) at 47.3%, Fergus County (208 miles away) at 72.2% and Yellowstone County (224 miles away) at 43.1% have figures too. Pooled across 52 Montana counties, 47.4% of reported tests reached that level; across every county in the country with a figure, 36.3%.
Statewide for the same period, Sheridan County reported the highest share (75.7%) and Hill County the lowest (35.0%). EPA's 1993 map puts Roosevelt County in Zone 1, the map's highest label: a predicted county average above 4 pCi/L. USGS geology rates 100% of the county's land high radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Roosevelt County, Geology
The ground under Roosevelt County
PredictedUSGS's geologic map puts all of Roosevelt County's mapped land in one class: high radon potential. All of it lies in the area the map calls Great Plains (Glaciated), to which USGS gives a radon index of 13, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Great Plains (Glaciated) | Glacial deposits derived from Cretaceous shales containing higher than average amounts of uranium. | High | 13 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Roosevelt County beside the ground around it
Roosevelt County has more high-potential ground than Montana as a whole: 100% of its land against 78.5%. Of the 7 counties that border it, none has as large a share of high-potential ground; Daniels County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Roosevelt County, Local resources
Radon testing and mitigation in Roosevelt County
- Radon Control ProgramRadon Control Program, run by Montana DEQ, does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Montana.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
Energy Bureau staff manage the radon information toll-free hotline and distribute subsidized radon test kits to Montana residents.
- Compare kits
- See the Montana directoryNo professionals are listed in Montana yet. The state program can point you to registered testers and mitigators.
What Montana's program says
- Phone
- 1-800-546-0483
- Licensing of radon professionals
Montana DEQ does not certify or require proof of certification for the contractors listed.
What it means
Roosevelt County, Questions
Questions about radon in Roosevelt County
Are radon levels high in Roosevelt County?
Over the 2008 to 2017 laboratory totals, 93.8% of the radon tests reported to CDC for Roosevelt County, Montana were at or above 4 pCi/L, and the median reported pre-mitigation result was 8.7 pCi/L. Of the counties bordering it, 5 have a figure over the 2006 to 2015 laboratory totals: Sheridan County reported the largest share at or above 4 pCi/L, 75.7%, and Williams County, ND the smallest, 35.4%, with Richland County at 75.0%, McKenzie County, ND at 65.2% and Valley County at 50.0% between.
Which counties border Roosevelt County?
Roosevelt County borders 7 counties: Sheridan County, MT, Richland County, MT, Daniels County, MT, McCone County, MT, Williams County, ND, Valley County, MT and McKenzie County, ND.
Products
Roosevelt County, Products
Testing a home in Roosevelt County
No CDC figure names Roosevelt County; the nearest county with one, Sheridan County (38 miles away), reported 75.7% of its tests at or above 4 pCi/L over the 2006 to 2015 laboratory totals, the only reading nearby until a test of this home. In Zone 1 the year-round level in Roosevelt 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
lüft plug-in radon and indoor air quality monitor
- C-NRPP 2024/25: Approved
- Plug-in
- Wi-Fi, Bluetooth
- App only
First reading: Within 90 minutes
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
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Roosevelt County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Roosevelt County
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Roosevelt County, Bordering counties
Counties bordering Roosevelt County
Calculated by Radon411- Radon levels in Sheridan County, MTEPA zone 1
75.7%at or above 4 pCi/L
Median 6.3 pCi/L · 70 tests
- Radon levels in Richland County, MTEPA zone 1
75.0%at or above 4 pCi/L
Median 5.6 pCi/L · 40 tests
- Radon levels in McKenzie County, NDEPA zone 1
65.2%at or above 4 pCi/L
Median 5.1 pCi/L · 46 tests
- Radon levels in Valley County, MTEPA zone 1
50.0%at or above 4 pCi/L
Median 4.2 pCi/L · 40 tests
- Radon levels in Williams County, NDEPA zone 1
35.4%at or above 4 pCi/L
Median 3.0 pCi/L · 280 tests
- Radon levels in McCone County, MTEPA zone 1
25.0%at or above 4 pCi/L
Median 2.5 pCi/L · 4 tests
- Radon levels in Daniels County, MTEPA zone 1
0.0%at or above 4 pCi/L
Median 2.3 pCi/L · 4 tests
Roosevelt County, Cities and towns
Cities and towns in Roosevelt County
Roosevelt County has been losing residents: from 10,808 in 2020 to 10,242 on July 1, 2025, a fall of 5.2% by the Census Bureau's estimates. Spread over its land, that is 4.3 people to the square mile. Its largest town, Wolf Point, has 2,531 residents, 24.7% of the total. Together its 5 incorporated places hold 43.1% of those residents; the other 56.9% live outside any of them. Reported testing is thin here: 17 tests over 2007 to 2016, or 1.7 for every 1,000 residents (2025 estimate), where Montana as a whole comes to 8.1.
From Wolf Point to Froid, CDC publishes no figure by town: each reads Roosevelt County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Wolf Point | 2,531 | −5.3% | 24.7% |
| Poplar | 722 | −5.5% | 7.0% |
| Culbertson | 715 | −4.9% | 7.0% |
| Bainville | 266 | −4.7% | 2.6% |
| Froid | 184 | −5.2% | 1.8% |
5 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).
Roosevelt County, Homes
Homes in Roosevelt County
Roosevelt County is a place of houses on their own lots: 77% of its 4,058 homes are detached single-family houses, against 69% across Montana. Half of its homes were built before 1973, close to Montana's 1980: 33% date from before 1960 and 13% from 2000 or later. 69% of occupied homes are lived in by their owner (Montana: 69%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Roosevelt County | Montana |
|---|---|---|
| Housing units | 4,058 | 522,939 |
| Detached houses | 77% | 69% |
| In buildings of 5 or more | 5% | 9% |
| Mobile homes | 11% | 10% |
| Built before 1960 | 33% | 26% |
| Built since 2000 | 13% | 27% |
| Middle year built | 1973 | 1980 |
| Owner-occupied | 69% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.