Locations and reports
Radon in Bozeman, Montana
EPA puts Gallatin County, where Bozeman is, in Zone 1, its highest radon zone, and high results are common there: 42.8% of the 1,600 radon tests reported to CDC (2008 to 2017, laboratory totals) 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
42.8%
2.7 pts below MT
- Gallatin
- 42.8%
- Montana
- 45.5%
Gallatin, 19th of 23 in MT, 2008 to 2017
Median result
3.2pCi/L
Below action level
- Gallatin
- 3.2 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of Gallatin's tests, 2008 to 2017
Nearest county
60.0%
Park, 29 miles
- Park
- 60.0%
- Gallatin
- 42.8%
150 tests, 2008 to 2017
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
Gallatin, where Bozeman is
Tests reported
1,600
In Gallatin
- Gallatin
- 1,600
- Park
- 150
Reported to CDC before any fix, 2008 to 2017
Read a result for Bozeman
Starts at Gallatin County's median, 3.2 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 3.2 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. Gallatin County's median reported result, 2008 to 2017.
The data
Bozeman, What is published
What is published for Bozeman
Every figure for Bozeman is a county's
Radon data is published by county, not by city, so for Bozeman it is Gallatin County's: its EPA zone (Zone 1) and the 1,600 tests reported to CDC for 2008 to 2017, laboratory. Only a test tells you about one home.
Bozeman covers 20.6 square miles of land, all of it in Gallatin County. About 58,814 people live there, 2,855 to the square mile.
Bozeman, Counties
The county Bozeman lies in
MeasuredGallatin County's EPA zone and the figures CDC publishes for it, 2008 to 2017, laboratory.
Gallatin CountyZone 1Highest predicted potential
- 42.8%
- Reported tests at or above 4 pCi/L
- 3.2 pCi/L
- Median reported result
- 1,600 tests
- Tests reported to CDC
- None
- Yearly figures on file
Gallatin County ranks 19th of 23 Montana counties with 30 or more tests for that period, 2.7 points below the 45.5% pooled across Montana's counties, 7.1 points above the national pool of 35.7%.
Measured from the middle of Bozeman, the nearest counties with a CDC figure for 2008 to 2017, laboratory are Park County (29 miles, 60.0% of 150 tests), Madison County (50 miles, 50.0% of 58 tests) and Jefferson County (59 miles, 71.0% of 62 tests). Across the 8 nearest, the share at or above 4 pCi/L runs from 50.0% to 71.0%; the farthest of them, Carbon County, is 103 miles away at 52.2%.
No business in the directory gives Bozeman as its address; the Montana list covers it. Montana's other cities with a page of their own: Kalispell, Billings, Boulder and Helena.
The counties around Bozeman
By distance from the middle of Bozeman; counties with 30 or more tests.
Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2008 to 2017, laboratory.
Bozeman, Geology
The ground under Bozeman
PredictedUSGS's geologic map puts all of Bozeman's mapped land in one class: high radon potential. All of it lies in the area the map calls Northern Rocky Mountains, 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 |
|---|---|---|---|---|
| Northern Rocky Mountains | Granitic, metaigneous, metasedimentary rocks, valley fill colluvium and alluvium. | 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.
Bozeman beside its county and Montana
Bozeman sits on more high-potential ground than Gallatin County as a whole: 100% of the city against 79.0% of the county. Bozeman has more high-potential ground than Montana as a whole: 100% of its land against 78.5%.
The map rates the ground, not the air in any home.
Bozeman, Homes
Homes in Bozeman
Fewer than six in ten of Bozeman's 24,846 homes are detached houses (43%, against 60% across Gallatin County); the rest are attached, in shared buildings or mobile. Half of its homes were built before 1998, close to Gallatin County's 1997: 17% date from before 1960 and 48% from 2000 or later. Most occupied homes here are rented: owners live in 45% (Gallatin County: 62%). A tenant can run a test; a fix is the landlord's to make.
| Homes | Bozeman | Gallatin County | Montana |
|---|---|---|---|
| Housing units | 24,846 | 55,589 | 522,939 |
| Detached houses | 43% | 60% | 69% |
| In buildings of 5 or more | 25% | 14% | 9% |
| Mobile homes | 2% | 6% | 10% |
| Built before 1960 | 17% | 13% | 26% |
| Built since 2000 | 48% | 45% | 27% |
| Middle year built | 1998 | 1997 | 1980 |
| Owner-occupied | 45% | 62% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.
Local help
Bozeman, Local resources
Local resources for Bozeman
Who to ask in Montana: its radon program, test kits and professionals.
- Radon Control ProgramRun by Montana DEQ, phone 1-800-546-0483.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
- Professionals in MontanaRadon testers and mitigators in Montana, each with how its listing was checked.
The program's own words on licensing are on the Montana page.
What it means
Bozeman, Questions
Questions about radon in Bozeman
What radon zone is Bozeman in?
EPA's map puts Gallatin County, and with it Bozeman, in Zone 1, the map's highest class: a predicted county average above 4 pCi/L.
What are radon levels in Bozeman?
High results are ordinary around Bozeman: 42.8% of the 1,600 tests reported from Gallatin County for 2008 to 2017 (laboratory totals) were at or above 4 pCi/L, the level at which EPA says to fix a home. The median reported result was 3.2 pCi/L.
Should I test my home in Bozeman?
Yes. Gallatin County reported about 685 of its 1,600 tests at or above 4 pCi/L. That is below Montana's pooled 45.5%, and still not a reason to skip it, and ranks Gallatin County 19th of the 23 Montana counties with 30 or more tests. Which homes they were, no map can say. How to test a home.
What ground is Bozeman built on, as far as radon goes?
USGS's geologic map puts all of Bozeman on one named area, "Northern Rocky Mountains", rated high for radon potential, radon index 13.
Is radon higher in the counties around Bozeman?
Higher, in every direction measured: all 8 of the nearest counties with a figure report a larger share of high tests than Gallatin County's 42.8%, up to Jefferson County (71.0%, 59 miles off).
The answers use the published figures of Gallatin County, the county Bozeman lies in.
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