34%tests ≥ 4 pCi/L
2,452tests on record
2.5median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Knox County

ResultShareEPA guidance
Below 2 pCi/L40%Below EPA's levels
2 to 4 pCi/L26%Consider fixing
4 pCi/L or more34%EPA recommends fixing

What the data shows

Where Knox County sits among Tennessee's 95 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 Knox County compares

Knox County has the lowest 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
Jefferson County57%Loudon County54%Sevier County53%Anderson County48%Grainger County48%Blount County43%Union County38%Roane County34%Knox County34%Tennessee 33%
Data table
AreaTests ≥ 4 pCi/LTests
Jefferson County57%146
Loudon County54%859
Sevier County53%328
Anderson County48%269
Grainger County48%56
Blount County43%745
Union County38%53
Roane County34%258
Knox County34%2,452
Tennessee (95 counties)33%31,066

Same source as Knox County.

What it means for your home

About 1 in 3 results in Knox 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: 2,452. 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