30%tests ≥ 4 pCi/L
6,751tests on record
2.5median pCi/L
Zone 2EPA zone (1993 prediction)

Test results in Lake County

ResultShareEPA guidance
Below 2 pCi/L39%Below EPA's levels
2 to 4 pCi/L30%Consider fixing
4 pCi/L or more30%EPA recommends fixing

What the data shows

Where Lake County sits among Illinois's 102 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%80%

How Lake County compares

Lake County ranks 2 of 3 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
McHenry County42%Lake County30%Cook County20%Illinois 43%
Data table
AreaTests ≥ 4 pCi/LTests
McHenry County42%2,777
Lake County30%6,751
Cook County20%14,199
Illinois (102 counties)43%108,909

Same source as Lake County. Other bordering counties: Allegan County, Michigan, Berrien County, Michigan, Kenosha County, Wisconsin, Van Buren County, Michigan.

What it means for your home

About 1 in 3 results in Lake 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: 6,751. 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