Short-term kitKidde
442020 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 3 days
Locations and reports
Radon Levels in Navajo County, Arizona
EPA puts Navajo County in Zone 2, its middle radon zone, and only 16 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
30.0%
Coconino County
- Coconino
- 30.0%
1 of 5 neighbours have 30+ tests, 2008 to 2017
Nearest county
30.0%
Coconino County, 87 miles
- Coconino
- 30.0%
- Arizona
- 16.8%
Share at 4+ pCi/L, 273 tests, 2008 to 2017
Ground above low
100.0%
42.8 pts above Arizona
- Navajo
- 100.0%
- Arizona
- 57.2%
Share of land USGS rates moderate or high potential
Tests reported
16
Too few for a share
- Navajo
- 16
- 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 Navajo 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
Navajo County, At a glance
Navajo County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Navajo County is a
USGS geologic potential: Moderate across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Navajo County, 2008 to 2017, laboratory
CDC holds 16 reported tests for Navajo County over the 2008 to 2017 laboratory totals, with a median of 1.1 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Navajo County beside the counties around it is how this page reads it.
What these figures count
Only 16 tests were reported to CDC for Navajo 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).
Navajo County, Compared
Navajo County radon figures, compared
Calculated by Radon411CDC's largest figure for Navajo County rests on 16 tests over the 2008 to 2017 laboratory totals, 0 of them at or above 4 pCi/L, so each test moves its share by 6.3 points and no rank or comparison is drawn from it. Results reached as high as 3.9 pCi/L, with a middle value of 1.1 pCi/L.
Coconino County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 30.0% of its tests at or above 4 pCi/L. Farther out, Yavapai County (138 miles away) at 16.2%, Pinal County (182 miles away) at 8.9% and Maricopa County (188 miles away) at 17.4% have figures too. Pooled across 13 Arizona counties, 16.8% of reported tests reached that level; across every county in the country with a figure, 35.7%.
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 Navajo County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 100% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Navajo County, Geology
The ground under Navajo County
PredictedUSGS's geologic map puts all of Navajo County's mapped land in one class: moderate radon potential. The map puts 30.5% of Navajo County in the area it calls Black Mesa and 25.9% in Colorado Plateau, with 3 smaller areas beside them. USGS gives both a radon index of 11, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Black Mesa | Cretaceous marine sandstones and shales. | Moderate | 11 | 30.5% |
| Colorado Plateau | Jurassic-Triassic nonmarine sandstones and shales. | Moderate | 11 | 25.9% |
| Colorado Plateau | Paleozoic sadstone, shale, and limestones, some Precambrian gneiss, metasedimentary rocks, granites. | Moderate | 9 | 23.1% |
| Colorado Plateau | Triassic and Jurassic eolian sandstones. | Moderate | 9 | 19.6% |
| Transition Zone | Precambrian igneous, metamorphic and sedimentary rocks and Tertiary volcanic rocks. | Moderate | 10 | 0.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Navajo County beside the ground around it
Across Arizona 0.1% of the land is rated high; none of Navajo County's is. Of the 5 counties that border it, 2 have more high-potential ground, San Juan County, UT the most at 21.7%.
The map rates the ground, not the air in any home.
Local help
Navajo County, Local resources
Radon testing and mitigation in Navajo 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
Navajo County, Questions
Questions about radon in Navajo County
Are radon levels high in Navajo County?
Over the 2008 to 2017 laboratory totals, 0.0% of the radon tests reported to CDC for Navajo County, Arizona were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.1 pCi/L. Coconino County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 30.0% of its tests at or above 4 pCi/L.
Which counties border Navajo County?
Navajo County borders 5 counties: Apache County, AZ, Coconino County, AZ, Gila County, AZ, Graham County, AZ and San Juan County, UT.
Products
Navajo County, Products
Testing a home in Navajo County
No CDC figure names Navajo County; the nearest county with one, Coconino County (87 miles away), reported 30.0% 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 Navajo 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
RadonEye RD200 plug-in continuous radon monitor
- C-NRPP 2024/25: Approved
- Plug-in
- Bluetooth
- Alarm
- Screen, app
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
Navajo County, Bordering counties
Counties bordering Navajo County
Calculated by Radon411- Radon levels in San Juan County, UTEPA zone 2
66.7%at or above 4 pCi/L
Median 5.1 pCi/L · 15 tests
- Radon levels in Gila County, AZEPA zone 2
64.7%at or above 4 pCi/L
Median 5.7 pCi/L · 17 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 Coconino County, AZEPA zone 2
30.0%at or above 4 pCi/L
Median 2.3 pCi/L · 273 tests
- Radon levels in Apache County, AZEPA zone 2
0.0%at or above 4 pCi/L
Median 1.9 pCi/L · 4 tests
Navajo County, Cities and towns
Cities and towns in Navajo County
The Census Bureau estimates 109,946 residents in Navajo County for July 1, 2025, 3,198 more than in 2020 (+3.0%). That works out to 11 people per square mile of land. No town dominates: Show Low, the largest, has 12,471 residents, 11.3% of the total. Together its 6 incorporated places hold 37.5% of those residents; the other 62.5% live outside any of them. Reported testing is thin here: 16 tests over 2008 to 2017, or 0.1 for every 1,000 residents (2025 estimate), where Arizona as a whole comes to 0.5.
From Show Low to Pinetop-Lakeside, CDC publishes no figure by town: each reads Navajo County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Show Low | 12,471 | +6.0% | 11.3% |
| Winslow | 8,464 | −5.9% | 7.7% |
| Snowflake | 6,902 | +13.0% | 6.3% |
| Holbrook | 4,866 | +0.4% | 4.4% |
| Taylor | 4,408 | +10.4% | 4.0% |
| Pinetop-Lakeside | 4,149 | +3.4% | 3.8% |
6 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).
Navajo County, Homes
Homes in Navajo County
Of Navajo County's 56,946 homes, 71% are detached houses, against 64% across Arizona; 19% are mobile homes. Half of its homes were built before 1988, close to Arizona's 1992: 8% date from before 1960 and 30% from 2000 or later. 73% 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 | Navajo County | Arizona |
|---|---|---|
| Housing units | 56,946 | 3,142,443 |
| Detached houses | 71% | 64% |
| In buildings of 5 or more | 3% | 16% |
| Mobile homes | 19% | 10% |
| Built before 1960 | 8% | 8% |
| Built since 2000 | 30% | 35% |
| Middle year built | 1988 | 1992 |
| Owner-occupied | 73% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.