43%tests ≥ 4 pCi/L
93tests on record
3.6median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Richland County

ResultShareEPA guidance
Below 2 pCi/L24%Below EPA's levels
2 to 4 pCi/L33%Consider fixing
4 pCi/L or more43%EPA recommends fixing

What the data shows

Where Richland County sits among North Dakota's 53 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%100%

How Richland County compares

Richland 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
Marshall County, South Da…81%Sargent County75%Ransom County62%Cass County58%Roberts County, South Dak…46%Richland County43%North Dakota 59%
Data table
AreaTests ≥ 4 pCi/LTests
Marshall County, South Dakota81%16
Sargent County75%24
Ransom County62%151
Cass County58%862
Roberts County, South Dakota46%26
Richland County43%93
North Dakota (53 counties)59%6,607

Same source as Richland County. Other bordering counties: Clay County, Minnesota, Traverse County, Minnesota, Wilkin County, Minnesota.

What it means for your home

About 1 in 2 results in Richland 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: 93. 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