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 Teton County, Montana
EPA puts Teton County in Zone 1, its highest radon zone, and only 7 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
63.5%
Lewis and Clark County
- Lewis and Clark
- 63.5%
- Cascade
- 35.9%
3 of 5 neighbours have 30+ tests, 2006 to 2015
Nearest county
63.5%
Lewis and Clark County, 50 miles
- Lewis and Clark
- 63.5%
- Montana
- 47.4%
Share at 4+ pCi/L, 395 tests, 2006 to 2015
Ground above low
100.0%
Level with Montana
- Teton
- 100.0%
- Montana
- 100.0%
Share of land USGS rates moderate or high potential
Tests reported
11
Too few for a share
- Teton
- 11
- Needed
- 30
2005 to 2014, 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 Teton 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
Teton County, At a glance
Teton County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Teton 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 Teton County, 2008 to 2017, laboratory
CDC holds 7 reported tests for Teton County over the 2008 to 2017 laboratory totals, with a median of 3.1 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Teton County beside the counties around it is how this page reads it.
What these figures count
Only 7 tests were reported to CDC for Teton 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).
Teton County, Compared
Teton County radon figures, compared
Calculated by Radon411CDC's largest figure for Teton County rests on 11 tests over the 2005 to 2014 laboratory totals, 2 of them at or above 4 pCi/L, so each test moves its share by 9.1 points and no rank or comparison is drawn from it. Results reached as high as 12.5 pCi/L, with a middle value of 2.4 pCi/L.
Of the counties bordering it, 3 have a figure over the 2006 to 2015 laboratory totals: Lewis and Clark County reported the largest share at or above 4 pCi/L, 63.5%, and Cascade County the smallest, 35.9%, with Flathead County at 38.0% between. Farther out, Lake County (87 miles away) at 38.0%, Missoula County (96 miles away) at 48.8% and Judith Basin County (108 miles away) at 64.3% 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 Teton 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.
Teton County, Geology
The ground under Teton County
PredictedUSGS's geologic map puts all of Teton County's mapped land in one class: high radon potential. The map puts 77.9% of Teton County in the area it calls Northern Rocky Mountains and 22.1% in Great Plains (Glaciated). USGS gives both 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 |
|---|---|---|---|---|
| Northern Rocky Mountains | Granitic, metaigneous, metasedimentary rocks, valley fill colluvium and alluvium. | High | 13 | 77.9% |
| Great Plains (Glaciated) | Glacial deposits derived from Cretaceous shales containing higher than average amounts of uranium. | High | 13 | 22.1% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Teton County beside the ground around it
Teton County has more high-potential ground than Montana as a whole: 100% of its land against 78.5%. Of the 5 counties that border it, none has as large a share of high-potential ground; Flathead County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Teton County, Local resources
Radon testing and mitigation in Teton 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
Teton County, Questions
Questions about radon in Teton County
Are radon levels high in Teton County?
Over the 2008 to 2017 laboratory totals, 28.6% of the radon tests reported to CDC for Teton County, Montana were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.1 pCi/L. Of the counties bordering it, 3 have a figure over the 2006 to 2015 laboratory totals: Lewis and Clark County reported the largest share at or above 4 pCi/L, 63.5%, and Cascade County the smallest, 35.9%, with Flathead County at 38.0% between.
Which counties border Teton County?
Teton County borders 5 counties: Pondera County, Lewis and Clark County, Cascade County, Chouteau County and Flathead County.
Products
Teton County, Products
Testing a home in Teton County
No CDC figure names Teton County; the nearest county with one, Lewis and Clark County (50 miles away), reported 63.5% 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 Teton 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
EcoQube Wi-Fi continuous radon monitor
- C-NRPP 2024/25: Approved
- Plug-in
- Wi-Fi
- App only
Method: Ion chamber
First reading: Within 10 minutes
Short-term kit
Air Chek Short-Term radon test kit you hang, lab fee included
- Lab fee included
In home: 72 to 168 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Teton County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Teton County
Explore
Teton County, Bordering counties
Counties bordering Teton County
Calculated by Radon411- Radon levels in Lewis and Clark CountyEPA zone 1
63.5%at or above 4 pCi/L
Median 5.1 pCi/L · 395 tests
- Radon levels in Chouteau CountyEPA zone 1
58.3%at or above 4 pCi/L
Median 5.1 pCi/L · 12 tests
- Radon levels in Flathead CountyEPA zone 1
38.0%at or above 4 pCi/L
Median 2.8 pCi/L · 924 tests
- Radon levels in Cascade CountyEPA zone 1
35.9%at or above 4 pCi/L
Median 2.6 pCi/L · 284 tests
- Radon levels in Pondera CountyEPA zone 1
0.0%at or above 4 pCi/L
Median 1.1 pCi/L · 5 tests
Teton County, Cities and towns
Cities and towns in Teton County
The Census Bureau estimates 6,496 residents in Teton County for July 1, 2025, 244 more than in 2020 (+3.9%). Spread over its land, that is 2.9 people to the square mile. Its largest town, Choteau, has 1,825 residents, 28.1% of the total. Together its 3 incorporated places hold 45.3% of those residents; the other 54.7% live outside any of them. Reported testing is thin here: 11 tests over 2005 to 2014, or 1.7 for every 1,000 residents (2025 estimate), where Montana as a whole comes to 6.7.
From Choteau to Dutton, CDC publishes no figure by town: each reads Teton County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Choteau | 1,825 | +5.1% | 28.1% |
| Fairfield | 797 | +3.5% | 12.3% |
| Dutton | 318 | +3.9% | 4.9% |
3 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).
Teton County, Homes
Homes in Teton County
Teton County is a place of houses on their own lots: 85% of its 2,942 homes are detached single-family houses, against 69% across Montana. The homes are older than Montana's as a whole: half were built before 1961 (1980 for Montana), and 49% date from before 1960. 75% 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 | Teton County | Montana |
|---|---|---|
| Housing units | 2,942 | 522,939 |
| Detached houses | 85% | 69% |
| In buildings of 5 or more | 5% | 9% |
| Mobile homes | 7% | 10% |
| Built before 1960 | 49% | 26% |
| Built since 2000 | 14% | 27% |
| Middle year built | 1961 | 1980 |
| Owner-occupied | 75% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.