Short-term kit
PicoCan short-term charcoal canister radon test
- Lab fee included
Method: Charcoal
In home: 48 to 96 hours
Locations and reports
Radon Levels in Greenlee County, Arizona
EPA puts Greenlee County in Zone 2, its middle radon zone. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Nearest county
8.9%
Pinal County, 124 miles
- Pinal
- 8.9%
- Arizona
- 16.8%
Share at 4+ pCi/L, 101 tests, 2008 to 2017
Ground above low
97.7%
40.5 pts above Arizona
- Greenlee
- 97.7%
- Arizona
- 57.2%
Share of land USGS rates moderate or high potential
Tests reported
0
None published
A home here needs its own test
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 Greenlee 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
Greenlee County, At a glance
Greenlee County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Greenlee County is a
USGS geologic potential: Moderate across 98% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
No CDC test figures here
CDC has published no radon test figures for Greenlee County. Pinal County, 124 miles away, is the nearest county with a figure over the 2008 to 2017 laboratory totals.
Greenlee County, Compared
Greenlee County radon figures, compared
Calculated by Radon411CDC's county radon counts over the 2008 to 2017 laboratory totals cover 13 Arizona counties, and Greenlee County is not among them: no year's figure and no ten-year laboratory total names it. Pooled across 13 Arizona counties, 16.8% of reported tests reached that level; across every county in the country with a figure, 35.7%.
The nearest counties with a figure are Pinal County (124 miles away) at 8.9%, Pima County (167 miles away) at 6.8% and Maricopa County (188 miles away) at 17.4%. Statewide for the same period, Coconino County reported the highest share (30.0%) and Mohave County the lowest (4.1%).
EPA's 1993 map puts Greenlee County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 98% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Greenlee County, Geology
The ground under Greenlee County
PredictedMost of the ground under Greenlee County is one class on USGS's geologic map: 97.7% of its land is moderate radon potential, with 2.3% low. 97.7% of it lies in the area the map calls Transition Zone, to which USGS gives a radon index of 10, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Transition Zone | Precambrian igneous, metamorphic and sedimentary rocks and Tertiary volcanic rocks. | Moderate | 10 | 97.7% |
| Basin and Range/Sonoran Desert | Quaternary to Tertiary sediments, with uranium-bearing Tertiary volcanic rocks, highly variable volcanic, metamorphic, and sedimentary rocks, and eolian deposits | Low | 8 | 2.3% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Greenlee County beside the ground around it
Across Arizona 0.1% of the land is rated high; none of Greenlee County's is. Of the 6 counties that border it, 2 have more high-potential ground, Catron County, NM the most at 5.8%.
The map rates the ground, not the air in any home.
Local help
Greenlee County, Local resources
Radon testing and mitigation in Greenlee County
- Arizona's radon programArizona Department of Health ServicesArizona's radon program answers questions about testing, mitigation and the rules in Arizona.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- See the Arizona directoryNo professionals are listed in Arizona yet. The state program can point you to registered testers and mitigators.
What it means
Greenlee County, Questions
Questions about radon in Greenlee County
Are radon levels high in Greenlee County?
No CDC testing statistics are published here for Greenlee County, Arizona yet. Of the 6 nearest counties with a figure, within 310 miles, the share of tests at or above 4 pCi/L runs from 4.1% to 30.0%.
Which counties border Greenlee County?
Greenlee County borders 6 counties: Graham County, AZ, Grant County, NM, Catron County, NM, Cochise County, AZ, Hidalgo County, NM and Apache County, AZ.
Products
Greenlee County, Products
Testing a home in Greenlee County
No CDC figure names Greenlee County; the nearest county with one, Pinal County (124 miles away), reported 8.9% of its tests at or above 4 pCi/L over the 2008 to 2017 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 Greenlee 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
Monitor
RadonScan-Plus USB-powered radon monitor with Wi-Fi
- C-NRPP 2024/25: Not included
- Plug-in
- Wi-Fi
- Alarm
- Screen, app
First reading: Within 5 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Greenlee County, Bordering counties
Counties bordering Greenlee County
Calculated by Radon411- Radon levels in Grant County, NMEPA zone 2
46.7%at or above 4 pCi/L
Median 2.3 pCi/L · 15 tests
- Radon levels in Graham County, AZEPA zone 2
36.4%at or above 4 pCi/L
Median 3.0 pCi/L · 11 tests
- Radon levels in Cochise County, AZEPA zone 2
26.9%at or above 4 pCi/L
Median 2.8 pCi/L · 26 tests
- Radon levels in Catron County, NMEPA zone 2
0.0%at or above 4 pCi/L
Median 3.9 pCi/L · 1 test
- Radon levels in Apache County, AZEPA zone 2
0.0%at or above 4 pCi/L
Median 1.9 pCi/L · 4 tests
- Radon levels in Hidalgo County, NMEPA zone 2
No CDC figure for 2008 to 2017; its page reads it against its own neighbours.
Greenlee County, Cities and towns
Cities and towns in Greenlee County
About 9,312 people live in Greenlee County by the Census Bureau's estimate for July 1, 2025, 219 fewer than in 2020 (−2.3%). Spread over its land, that is 5.1 people to the square mile. Its largest town, Clifton, has 3,752 residents, 40.3% of the total. Together its 2 incorporated places hold 47.5% of those residents; the other 52.5% live outside any of them. CDC publishes no radon test count for Greenlee County; across Arizona its counts for 2008 to 2017 come to 0.5 tests for every 1,000 residents (2025 estimate).
From Clifton to Duncan, CDC publishes no figure by town: each reads Greenlee County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Clifton | 3,752 | −4.2% | 40.3% |
| Duncan | 672 | −2.5% | 7.2% |
2 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).
Greenlee County, Homes
Homes in Greenlee County
Of Greenlee County's 4,422 homes, 69% are detached houses, against 64% across Arizona; 21% are mobile homes. The homes are older than Arizona's as a whole: half were built before 1981 (1992 for Arizona), and 17% date from before 1960. 56% of occupied homes are lived in by their owner (Arizona: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Greenlee County | Arizona |
|---|---|---|
| Housing units | 4,422 | 3,142,443 |
| Detached houses | 69% | 64% |
| In buildings of 5 or more | 4% | 16% |
| Mobile homes | 21% | 10% |
| Built before 1960 | 17% | 8% |
| Built since 2000 | 10% | 35% |
| Middle year built | 1981 | 1992 |
| Owner-occupied | 56% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.