2%tests ≥ 4 pCi/L
48tests on record
0.9median pCi/L
Zone 3EPA zone (1993 prediction)

Test results in Yolo County

ResultShareEPA guidance
Below 2 pCi/L83%Below EPA's levels
2 to 4 pCi/L15%Consider fixing
4 pCi/L or more2%EPA recommends fixing

What the data shows

Where Yolo 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 Yolo County compares

Yolo County ranks 6 of 7 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Sutter County43%Solano County16%Lake County13%Napa County11%Sacramento County8%Yolo County2%Colusa County0%California 10%
Data table
AreaTests ≥ 4 pCi/LTests
Sutter County43%7
Solano County16%38
Lake County13%24
Napa County11%57
Sacramento County8%194
Yolo County2%48
Colusa County0%1
California (56 counties)10%9,415

Same source as Yolo County.

What it means for your home

About 1 in 48 results in Yolo 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: 48. 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