Radon levels in Arizona

Verified county-level radon indicators are available for 13 Arizona counties. Select a county for its source period and sample details.

High results are most common in Coconino County (30%) and least common in Mohave County (4%)Share of tests at or above 4 pCi/L by county · Radon test results from laboratories, 2008–2017 · 13 of 15 counties have data
Mohave County: 4% of tests at or above 4 pCi/L · 49 testsSanta Cruz County: 0% of tests at or above 4 pCi/L · 6 testsCoconino County: 30% of tests at or above 4 pCi/L · 273 testsLa Paz County: no dataGila County: 65% of tests at or above 4 pCi/L · 17 testsPima County: 7% of tests at or above 4 pCi/L · 410 testsGreenlee County: no dataPinal County: 9% of tests at or above 4 pCi/L · 101 testsNavajo County: 0% of tests at or above 4 pCi/L · 16 testsYuma County: 0% of tests at or above 4 pCi/L · 18 testsMaricopa County: 17% of tests at or above 4 pCi/L · 2,393 testsGraham County: 36% of tests at or above 4 pCi/L · 11 testsCochise County: 27% of tests at or above 4 pCi/L · 26 testsApache County: 0% of tests at or above 4 pCi/L · 4 testsYavapai County: 16% of tests at or above 4 pCi/L · 265 tests
  • Under 10%
  • 10–20%
  • 20–30%
  • 30–40%
  • 40% or more
  • No data

Counties

CountyTests% ≥ 4 pCi/LMedian (pCi/L)EPA zone (1993)Source
Apache County40%1.9Zone 2Radon test results from laboratories through 2017
Cochise County2627%2.8Zone 2Radon test results from laboratories through 2017
Coconino County27330%2.3Zone 2Radon test results from laboratories through 2017
Gila County1765%5.7Zone 2Radon test results from laboratories through 2017
Graham County1136%3.0Zone 2Radon test results from laboratories through 2017
Greenlee County———Zone 2—
La Paz County———Zone 2—
Maricopa County2,39317%1.6Zone 2Radon test results from laboratories through 2017
Mohave County494%0.2Zone 2Radon test results from laboratories through 2017
Navajo County160%1.1Zone 2Radon test results from laboratories through 2017
Pima County4107%1.1Zone 2Radon test results from laboratories through 2017
Pinal County1019%0.9Zone 2Radon test results from laboratories through 2017
Santa Cruz County60%1.7Zone 2Radon test results from laboratories through 2017
Yavapai County26516%1.6Zone 2Radon test results from laboratories through 2017
Yuma County180%0.6Zone 2Radon test results from laboratories through 2017

Test your home

County figures show how often tests come back high, not the level in your home. Only a test tells you that: see how to test for radon.

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