22%tests ≥ 4 pCi/L
105tests on record
1.2median pCi/L
Zone 2EPA zone (1993 prediction)

Test results in Santa Cruz County

ResultShareEPA guidance
Below 2 pCi/L60%Below EPA's levels
2 to 4 pCi/L18%Consider fixing
4 pCi/L or more22%EPA recommends fixing

What the data shows

Where Santa Cruz County sits among California's 56 counties with dataEach dot is a county's share of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017
0%20%40%60%

How Santa Cruz County compares

Santa Cruz County has the highest share of high results among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Santa Cruz County22%Monterey County15%Santa Clara County9%San Mateo County9%San Benito County0%California 10%
Data table
AreaTests ≥ 4 pCi/LTests
Santa Cruz County22%105
Monterey County15%87
Santa Clara County9%793
San Mateo County9%468
San Benito County0%19
California (56 counties)10%9,415

Same source as Santa Cruz County.

What it means for your home

About 1 in 5 results in Santa Cruz County were at or above 4 pCi/L, where the EPA recommends a fix. Only a test shows your own home's level.

Levels in pCi/L from the EPA. The WHO reference level is 100 Bq/m³, about 2.7 pCi/L.

Test your home

Start with a short-term test (2–90 days) and confirm a result of 4 pCi/L or more with a second test. EPA guide

Sponsored: we earn a commission on purchases through these links. We haven't tested Airthings monitors yet.

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Fixing high radon

No local job records yet. National range: $800–$2,500, average $1,200 (EPA, 2003). Cost guide →

About this data

Source: Radon test results from laboratories (CDC Environmental Public Health Tracking Network). Period: 2008–2017. Tests: 105. Read the methodology →

These are voluntary and real-estate tests, not a random sample of homes, so they describe tested homes rather than every home.

About this page

Published by Ray Roman, editor of Radon by County. Figures are loaded from the cited source and spot-checked against it. Editorial policy · About us