48%tests ≥ 4 pCi/L
350tests on record
3.5median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Clarke County

ResultShareEPA guidance
Below 2 pCi/L37%Below EPA's levels
2 to 4 pCi/L15%Consider fixing
4 pCi/L or more48%EPA recommends fixing

What the data shows

Where Clarke County sits among Virginia's 131 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 Clarke County compares

Clarke County ranks 3 of 7 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Jefferson County, West Vi…53%Berkeley County, West Vir…51%Clarke County48%Frederick County44%Warren County37%Fauquier County30%Loudoun County27%Virginia 30%
Data table
AreaTests ≥ 4 pCi/LTests
Jefferson County, West Virginia53%898
Berkeley County, West Virginia51%2,888
Clarke County48%350
Frederick County44%2,451
Warren County37%536
Fauquier County30%1,199
Loudoun County27%4,457
Virginia (131 counties)30%53,199

Same source as Clarke County.

What it means for your home

About 1 in 2 results in Clarke 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: 350. 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