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 Gunnison County, Colorado
EPA puts Gunnison County in Zone 1, its highest radon zone, and 34.7% of its 147 reported radon tests (2023) were 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
34.7%
4.2 pts below CO
- Gunnison
- 34.7%
- Colorado
- 38.9%
147 tests, 2023
Median result
2.5pCi/L
Below action level
- Gunnison
- 2.5 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
147
22nd of 38 by tests
- Gunnison
- 147
- Jefferson
- 3,068
Reported to CDC before any fix, 2023
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Colorado
30 of 38
Lowest quarter
- Gunnison
- 34.7%
- Park
- 57.5%
By share, of 38 with 30+ tests
Read a result for Gunnison County
Starts at Gunnison County's median, 2.5 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 2.5 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. Gunnison County's median reported result, 2023.
The data
Gunnison County, At a glance
Gunnison County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Gunnison County in
USGS geologic potential: High across 74% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Gunnison County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 51.9% |
| 2015 | 55.9% |
| 2016 | 52.7% |
| 2017 | 46.3% |
| 2018 | 45.2% |
| 2019 | 46.3% |
| 2020 | 45.6% |
| 2021 | 53.7% |
| 2022 | 39.7% |
| 2023 | 34.7% |
2023: 34.7%. Across these years the share ran from 34.7% to 55.9%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 147 tests reported to CDC for Gunnison County over 2023, many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Gunnison County, Compared
Gunnison County radon figures, compared
Calculated by Radon411In Gunnison County, about 3 in 10 reported tests in 2023 (51 of 147) were at or above EPA's action level. Against the national pool of 33.4%, the gap is 1.3 points higher. Across 61 Colorado counties pooled together, 38.9% of tests reached that level, so Gunnison County runs 4.2 points below its state.
Of 6 neighbours with a figure, 5 reported a larger share at or above 4 pCi/L and 1 a smaller one; the spread is 18.9% (Mesa County) to 55.6% (Delta County). By share, Gunnison County is 30th of 38 Colorado counties with 30 or more tests for the same period.
Year by year, 2014 opened at 51.9% and 2023 closed at 34.7% (down 17.2 points), with 2015 the high at 55.9%. Half the tests came in under 2.5 pCi/L and half over it; the single highest reached 38.9 pCi/L. Below the action level, 60 tests (40.8%) came in under 2 pCi/L, against 39.2% statewide, and 36 tests (24.5%) fell between 2 and 4, against 22.0% statewide.
Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 34.7% share point the same way here. USGS geology rates 74% of the county's land high radon potential. CDC also counts 5 tests taken after mitigation in Gunnison County for the same period: tests in homes where a fix was already in.
The busiest year on file was 2019, with 175 tests reported; the quietest, 2015, had 34.
Gunnison CountyColorado, pooled
| Year | Tests | Gunnison County, at or above 4 pCi/L | Colorado, pooled |
|---|---|---|---|
| 2014 | 52 | 51.9% | 46.5% |
| 2015 | 34 | 55.9% | 47.2% |
| 2016 | 55 | 52.7% | 38.5% |
| 2017 | 82 | 46.3% | 41.0% |
| 2018 | 135 | 45.2% | 44.2% |
| 2019 | 175 | 46.3% | 44.1% |
| 2020 | 171 | 45.6% | 41.9% |
| 2021 | 147 | 53.7% | 47.3% |
| 2022 | 131 | 39.7% | 38.6% |
| 2023 | 147 | 34.7% | 38.9% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Gunnison County, State data
Colorado's own radon test data
MeasuredWhat Colorado's own agencies publish about radon tests in Gunnison County, with their period. These are not CDC's figures and are never added to them.
MeasuredState figures, not CDC's
What Colorado CDPHE reports for Gunnison County
Radon data (county results): radon test results received from radon testing labs, primarily short-term household tests taken by the homeowner. Period: 2005-2025.
Share over 4 pCi/L
39.5%
669 of 1,693 tests
Median result
2.7 pCi/L
Highest result
263.0 pCi/L
Tests behind these figures
1,693 tests
- CDPHE says these data do not give actual radon levels in homes that have not been tested.
- When possible, only tests conducted before a mitigation system was installed are used.
- Some counties have very small numbers of test results, and their summaries may be less representative.
- These figures describe tests reported to Colorado CDPHE in this area. They count a different set of tests than CDC's figures and are not a reading of any one home.
Measured: Colorado CDPHE data, 2005-2025.
Gunnison County, Geology
The ground under Gunnison County
PredictedUSGS's geologic map splits Gunnison County: 74.1% of its land is high radon potential and 25.9% moderate. The map puts 41.3% of Gunnison County in the area it calls Rocky Mountains and 28.9% in Mancos Shale Lowlands, with 3 smaller areas beside them. USGS gives the first a radon index of 15 and the second 13, both in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Rocky Mountains | Precambrian granites, gneiss, amphibolite, variable uranium content, abundant shear zones.Sedimentary rocks shed from the granitic highlands. | High | 15 | 41.3% |
| Mancos Shale Lowlands | Marine shales (Mancos Shale) and Tertiary sandstones. | High | 13 | 28.9% |
| Western Slope | Paleozoic and Mesozoic sandstone, siltstone, shale, basalt. | Moderate | 11 | 14.4% |
| San Juan Volcanic field | Volcanic rocks, rhyolite, tuff, basalt | Moderate | 11 | 11.5% |
| Paradox Basin | Tertiary sandstone, siltstone and shale. | High | 13 | 3.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Gunnison County beside the ground around it
On high-potential ground Gunnison County is close to Colorado as a whole: 74.1% of its land against 74.8%. Of the 8 counties that border it, 4 have more high-potential ground, Delta County the most at 100%.
The map rates the ground, not the air in any home.
Local help
Gunnison County, Local resources
Radon testing and mitigation in Gunnison County
- Colorado's radon programColorado Department of Public Health and EnvironmentColorado's radon program licenses or certifies radon professionals, offers free or discounted test kits and states the rule for disclosing radon when a home is sold, and answers questions about testing and mitigation in Colorado.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
Order a discounted radon test kit
- Compare kits
- Professionals in Colorado25 professionals are listed in Colorado.
What Colorado's program says
- Licensing of radon professionals
Listed contractors are certified by the National Radon Proficiency Program or the National Radon Safety Board, and must be licensed by the Colorado Department of Regulatory Agencies.
- Disclosure when a home is sold or rented
As of August 7, 2023, landlords in Colorado are required to disclose radon information when a tenant signs a lease agreement.
What it means
Gunnison County, Questions
Questions about radon in Gunnison County
Are radon levels high in Gunnison County?
In 2023, 34.7% of the radon tests reported to CDC for Gunnison County, Colorado were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.5 pCi/L. Of 38 Colorado counties with 30 or more tests for the same period, 29 reported a higher share; pooled, the state comes to 38.9%.
Which counties border Gunnison County?
Gunnison County borders 8 counties: Pitkin County, Chaffee County, Delta County, Saguache County, Ouray County, Hinsdale County, Montrose County and Mesa County.
Products
Gunnison County, Products
Testing a home in Gunnison County
In Gunnison County, 34.7% of 147 tests reported to CDC in 2023 reached 4 pCi/L, against 38.9% pooled across Colorado. In Zone 1 the year-round level in Gunnison 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-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
Short-term kitFirst Alert
RD1 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 2 to 4 days
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Gunnison County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Gunnison County
Explore
Gunnison County, Bordering counties
Counties bordering Gunnison County
Calculated by Radon411- Radon levels in Hinsdale CountyEPA zone 2
100.0%at or above 4 pCi/L
Median 6.8 pCi/L · 1 test · 65.3 points above Gunnison County
- Radon levels in Delta CountyEPA zone 1
55.6%at or above 4 pCi/L
Median 4.6 pCi/L · 124 tests · 20.9 points above Gunnison County
- Radon levels in Montrose CountyEPA zone 1
55.3%at or above 4 pCi/L
Median 4.5 pCi/L · 215 tests · 20.6 points above Gunnison County
- Radon levels in Chaffee CountyEPA zone 1
55.2%at or above 4 pCi/L
Median 4.5 pCi/L · 165 tests · 20.5 points above Gunnison County
- Radon levels in Saguache CountyEPA zone 2
41.7%at or above 4 pCi/L
Median 3.1 pCi/L · 12 tests · 7.0 points above Gunnison County
- Radon levels in Ouray CountyEPA zone 1
37.2%at or above 4 pCi/L
Median 1.2 pCi/L · 43 tests · 2.5 points above Gunnison County
- Radon levels in Pitkin CountyEPA zone 1
36.6%at or above 4 pCi/L
Median 2.5 pCi/L · 164 tests · 1.9 points above Gunnison County
- Radon levels in Mesa CountyEPA zone 1
18.9%at or above 4 pCi/L
Median 2.2 pCi/L · 567 tests · 15.8 points below Gunnison County
Gunnison County, Cities and towns
Cities and towns in Gunnison County
The Census Bureau estimates 17,439 residents in Gunnison County for July 1, 2025, 489 more than in 2020 (+2.9%). Spread over its land, that is 5.4 people to the square mile. Its largest town, Gunnison, has 6,836 residents, 39.2% of the total. Together its 5 incorporated places hold 55.6% of those residents; the other 44.4% live outside any of them. Testing is reported here more often than across the state: CDC's 147 reported tests for 2023 come to 8.4 for every 1,000 residents (2025 estimate), against 3.6 for Colorado.
From Gunnison to Pitkin, CDC publishes no figure by town: each reads Gunnison County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Gunnison | 6,836 | +4.0% | 39.2% |
| Crested Butte | 1,693 | +2.2% | 9.7% |
| Mount Crested Butte | 966 | +2.9% | 5.5% |
| Marble | 133 | −1.5% | 0.8% |
| Pitkin | 74 | −2.6% | 0.4% |
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).
Gunnison County, Homes
Homes in Gunnison County
Of Gunnison County's 12,348 homes, 64% are detached houses, against 62% across Colorado; 18% are in buildings of five or more homes. Half of its homes were built before 1988, close to Colorado's 1987: 12% date from before 1960 and 29% from 2000 or later. 67% of occupied homes are lived in by their owner (Colorado: 66%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Gunnison County | Colorado |
|---|---|---|
| Housing units | 12,348 | 2,545,124 |
| Detached houses | 64% | 62% |
| In buildings of 5 or more | 18% | 22% |
| Mobile homes | 5% | 4% |
| Built before 1960 | 12% | 16% |
| Built since 2000 | 29% | 31% |
| Middle year built | 1988 | 1987 |
| Owner-occupied | 67% | 66% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.