48%tests ≥ 4 pCi/L
512tests on record
3.6median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Clark County

ResultShareEPA guidance
Below 2 pCi/L31%Below EPA's levels
2 to 4 pCi/L21%Consider fixing
4 pCi/L or more48%EPA recommends fixing

What the data shows

Where Clark County sits among Indiana's 92 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 Clark County compares

Clark County has the highest 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
Clark County48%Jefferson County46%Trimble County, Kentucky46%Floyd County42%Washington County42%Jefferson County, Kentucky39%Oldham County, Kentucky37%Scott County35%Indiana 39%
Data table

Same source as Clark County.

What it means for your home

About 1 in 2 results in Clark 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: 512. 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