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 Santa Cruz County, Arizona
EPA puts Santa Cruz County in Zone 2, its middle radon zone, and only 6 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
6.8%
Pima County
- Pima
- 6.8%
1 of 2 neighbours have 30+ tests, 2008 to 2017
Nearest county
6.8%
Pima County, 68 miles
- Pima
- 6.8%
- Arizona
- 16.8%
Share at 4+ pCi/L, 410 tests, 2008 to 2017
Ground above low
None
57.2 pts below Arizona
- Santa Cruz
- 0.0%
- Arizona
- 57.2%
Share of land USGS rates moderate or high potential
Tests reported
14
Too few for a share
- Santa Cruz
- 14
- Needed
- 30
2007 to 2016, 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 Santa Cruz 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
Santa Cruz County, At a glance
Santa Cruz County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Santa Cruz County is a
USGS geologic potential: Low across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Santa Cruz County, 2008 to 2017, laboratory
CDC holds 6 reported tests for Santa Cruz County over the 2008 to 2017 laboratory totals, with a median of 1.7 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Santa Cruz County beside the counties around it is how this page reads it.
What these figures count
Only 6 tests were reported to CDC for Santa Cruz 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).
Santa Cruz County, Compared
Santa Cruz County radon figures, compared
Calculated by Radon411CDC's largest figure for Santa Cruz County rests on 14 tests over the 2007 to 2016 laboratory totals, 0 of them at or above 4 pCi/L, so each test moves its share by 7.1 points and no rank or comparison is drawn from it. Results reached as high as 2.5 pCi/L, with a middle value of 1.6 pCi/L.
Pima County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 6.8% of its tests at or above 4 pCi/L. Farther out, Pinal County (99 miles away) at 8.9%, Maricopa County (158 miles away) at 17.4% and Yavapai County (234 miles away) at 16.2% 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 Santa Cruz 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 low radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Santa Cruz County, Geology
The ground under Santa Cruz County
PredictedUSGS's geologic map puts all of Santa Cruz County's mapped land in one class: low radon potential. All of it lies in the area the map calls Basin and Range/Sonoran Desert, to which USGS gives a radon index of 8, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| 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 | 100% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Santa Cruz County beside the ground around it
Across Arizona 0.1% of the land is rated high; none of Santa Cruz County's is. Of the 2 counties that border it, 1 has more moderate-potential ground, Cochise County the most at 0.3%.
The map rates the ground, not the air in any home.
Local help
Santa Cruz County, Local resources
Radon testing and mitigation in Santa Cruz 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
Santa Cruz County, Questions
Questions about radon in Santa Cruz County
Are radon levels high in Santa Cruz County?
Over the 2008 to 2017 laboratory totals, 0.0% of the radon tests reported to CDC for Santa Cruz County, Arizona were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.7 pCi/L. Pima County, the one bordering county with a figure over the 2008 to 2017 laboratory totals, reported 6.8% of its tests at or above 4 pCi/L.
Which counties border Santa Cruz County?
Santa Cruz County borders 2 counties: Pima County and Cochise County.
Products
Santa Cruz County, Products
Testing a home in Santa Cruz County
No CDC figure names Santa Cruz County; the nearest county with one, Pima County (68 miles away), reported 6.8% 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 Santa Cruz 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
RadonPro Wi-Fi radon monitor with a built-in Geiger counter
- 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
Santa Cruz County, Bordering counties
Counties bordering Santa Cruz County
Calculated by Radon411- Radon levels in Cochise CountyEPA zone 2
26.9%at or above 4 pCi/L
Median 2.8 pCi/L · 26 tests
- Radon levels in Pima CountyEPA zone 2
6.8%at or above 4 pCi/L
Median 1.1 pCi/L · 410 tests
Santa Cruz County, Cities and towns
Cities and towns in Santa Cruz County
The Census Bureau estimates 50,020 residents in Santa Cruz County for July 1, 2025, 2,309 more than in 2020 (+4.8%). That works out to 40 people per square mile of land. Its largest town, Nogales, has 19,495 residents, 39.0% of the total. Together its 2 incorporated places hold 40.5% of those residents; the other 59.5% live outside any of them. Reported testing is thin here: 14 tests over 2007 to 2016, or 0.3 for every 1,000 residents (2025 estimate), where Arizona as a whole comes to 0.5.
From Nogales to Patagonia, CDC publishes no figure by town: each reads Santa Cruz County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Nogales | 19,495 | −1.3% | 39.0% |
| Patagonia | 771 | −3.5% | 1.5% |
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).
Santa Cruz County, Homes
Homes in Santa Cruz County
Of Santa Cruz County's 18,997 homes, 70% are detached houses, against 64% across Arizona; 7% are mobile homes. Half of its homes were built before 1990, close to Arizona's 1992: 11% date from before 1960 and 31% from 2000 or later. 68% 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 | Santa Cruz County | Arizona |
|---|---|---|
| Housing units | 18,997 | 3,142,443 |
| Detached houses | 70% | 64% |
| In buildings of 5 or more | 6% | 16% |
| Mobile homes | 7% | 10% |
| Built before 1960 | 11% | 8% |
| Built since 2000 | 31% | 35% |
| Middle year built | 1990 | 1992 |
| Owner-occupied | 68% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.