64%tests ≥ 4 pCi/L
270tests on record
5.6median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Darke County

ResultShareEPA guidance
Below 2 pCi/L14%Below EPA's levels
2 to 4 pCi/L22%Consider fixing
4 pCi/L or more64%EPA recommends fixing

What the data shows

Where Darke County sits among Ohio's 88 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 Darke County compares

Darke County ranks 2 of 9 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Miami County65%Darke County64%Preble County63%Randolph County, Indiana61%Shelby County60%Mercer County58%Wayne County, Indiana56%Montgomery County50%Jay County, Indiana44%Ohio 52%
Data table
AreaTests ≥ 4 pCi/LTests
Miami County65%690
Darke County64%270
Preble County63%212
Randolph County, Indiana61%28
Shelby County60%248
Mercer County58%149
Wayne County, Indiana56%140
Montgomery County50%2,922
Jay County, Indiana44%9
Ohio (88 counties)52%98,840

Same source as Darke County.

What it means for your home

More than half of all results in Darke 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: 270. 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