Short-term kit
RA400 short-term liquid scintillation radon test kit, lab fee included
- Lab fee included
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Treasure County, Montana
EPA puts Treasure County in Zone 2, its middle radon zone, and only 1 radon test from it is 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
43.1%
Yellowstone County
- Yellowstone
- 43.1%
1 of 3 neighbours have 30+ tests, 2006 to 2015
Nearest county
43.1%
Yellowstone County, 52 miles
- Yellowstone
- 43.1%
- Montana
- 47.4%
Share at 4+ pCi/L, 1,421 tests, 2006 to 2015
Ground above low
100.0%
Level with Montana
- Treasure
- 100.0%
- Montana
- 100.0%
Share of land USGS rates moderate or high potential
Tests reported
1
Too few for a share
- Treasure
- 1
- Needed
- 30
2008 to 2017, laboratory
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Read a result for Treasure 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
Treasure County, At a glance
Treasure County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Treasure County is a
USGS geologic potential: Moderate across 73% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Treasure County, 2008 to 2017, laboratory
CDC holds 1 reported test for Treasure County over the 2008 to 2017 laboratory totals, a result of 7.5 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Treasure County beside the counties around it is how this page reads it.
What these figures count
Only 1 test was reported to CDC for Treasure 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. Measured data period: 2008 to 2017.
Treasure County, Compared
Treasure County radon figures, compared
Calculated by Radon411CDC's largest figure for Treasure County rests on 1 test over the 2008 to 2017 laboratory totals, 1 of them at or above 4 pCi/L, so each test moves its share by 100.0 points and no rank or comparison is drawn from it. Results reached as high as 7.5 pCi/L, with a middle value of 7.5 pCi/L.
Yellowstone County, the one bordering county with a figure over the 2006 to 2015 laboratory totals, reported 43.1% of its tests at or above 4 pCi/L. Farther out, Carbon County (109 miles away) at 52.5%, Stillwater County (109 miles away) at 61.8% and Fergus County (118 miles away) at 72.2% 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 Treasure County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 73% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Treasure County, Geology
The ground under Treasure County
PredictedUSGS's geologic map splits Treasure County: 73.5% of its land is moderate radon potential and 26.5% high. The map puts 73.5% of Treasure County in the area it calls Plains and Mountains and 26.5% in Great Plains. USGS gives the first a radon index of 10, in the moderate band (9 to 11), and the second 12, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Plains and Mountains | Marine and continental shale, siltstone, and sandstone of Cretaceous and Tertiary ages, and volcanic rocks. | Moderate | 10 | 73.5% |
| Great Plains | Tertiary sandstone, siltstone, shale, coal. | High | 12 | 26.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Treasure County beside the ground around it
Montana as a whole has more high-potential ground than Treasure County: 78.5% of its land, against 26.5% here. Of the 3 counties that border it, 2 have more high-potential ground, Rosebud County the most at 56.2%.
The map rates the ground, not the air in any home.
Local help
Treasure County, Local resources
Radon testing and mitigation in Treasure 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
Treasure County, Questions
Questions about radon in Treasure County
Are radon levels high in Treasure County?
Over the 2008 to 2017 laboratory totals, 100.0% of the radon tests reported to CDC for Treasure County, Montana were at or above 4 pCi/L, and the median reported pre-mitigation result was 7.5 pCi/L. Yellowstone County, the one bordering county with a figure over the 2006 to 2015 laboratory totals, reported 43.1% of its tests at or above 4 pCi/L.
Which counties border Treasure County?
Treasure County borders 3 counties: Rosebud County, Big Horn County and Yellowstone County.
Products
Treasure County, Products
Testing a home in Treasure County
No CDC figure names Treasure County; the nearest county with one, Yellowstone County (52 miles away), reported 43.1% 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 2 a short-term kit (2 to 90 days) is the quick first check in Treasure County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
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
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
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Treasure County, Bordering counties
Counties bordering Treasure County
Calculated by Radon411- Radon levels in Rosebud CountyEPA zone 1
50.0%at or above 4 pCi/L
Median 4.4 pCi/L · 6 tests
- Radon levels in Yellowstone CountyEPA zone 2
43.1%at or above 4 pCi/L
Median 3.5 pCi/L · 1,421 tests
- Radon levels in Big Horn CountyEPA zone 1
25.0%at or above 4 pCi/L
Median 1.9 pCi/L · 20 tests
Treasure County, Cities and towns
Cities and towns in Treasure County
About 728 people live in Treasure County by the Census Bureau's estimate for July 1, 2025, 30 fewer than in 2020 (−4.0%). Spread over its land, that is 0.7 people to the square mile. Hysham, its one incorporated place, has 262 residents, 36.0% of the total. Reported testing is thin here: 1 test over 2008 to 2017, or 1.4 for every 1,000 residents (2025 estimate), where Montana as a whole comes to 8.6.
Hysham is the one incorporated place here; CDC publishes no figure by town, so it reads Treasure County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Hysham | 262 | −4.0% | 36.0% |
One incorporated place, 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).
Treasure County, Homes
Homes in Treasure County
Treasure County is a place of houses on their own lots: 82% of its 479 homes are detached single-family houses, against 69% across Montana. The homes are older than Montana's as a whole: half were built before 1970 (1980 for Montana), and 39% date from before 1960. 66% 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 | Treasure County | Montana |
|---|---|---|
| Housing units | 479 | 522,939 |
| Detached houses | 82% | 69% |
| In buildings of 5 or more | 2% | 9% |
| Mobile homes | 14% | 10% |
| Built before 1960 | 39% | 26% |
| Built since 2000 | 17% | 27% |
| Middle year built | 1970 | 1980 |
| Owner-occupied | 66% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.