17%tests ≥ 4 pCi/L
228tests on record
1.3median pCi/L
Zone 2EPA zone (1993 prediction)

Test results in Madison County

ResultShareEPA guidance
Below 2 pCi/L63%Below EPA's levels
2 to 4 pCi/L20%Consider fixing
4 pCi/L or more17%EPA recommends fixing

What the data shows

Where Madison County sits among North Carolina's 99 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%10%20%30%40%50%

How Madison County compares

Madison 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
Cocke County, Tennessee46%Greene County, Tennessee46%Unicoi County, Tennessee37%Yancey County31%Haywood County31%Buncombe County29%Madison County17%North Carolina 23%
Data table
AreaTests ≥ 4 pCi/LTests
Cocke County, Tennessee46%56
Greene County, Tennessee46%385
Unicoi County, Tennessee37%132
Yancey County31%290
Haywood County31%1,872
Buncombe County29%6,359
Madison County17%228
North Carolina (99 counties)23%73,139

Same source as Madison County.

What it means for your home

About 1 in 6 results in Madison 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: 228. 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