5%tests ≥ 4 pCi/L
671tests on record
0.7median pCi/L
Zone 3EPA zone (1993 prediction)

Test results in Richland County

ResultShareEPA guidance
Below 2 pCi/L86%Below EPA's levels
2 to 4 pCi/L9%Consider fixing
4 pCi/L or more5%EPA recommends fixing

What the data shows

Where Richland County sits among South Carolina's 46 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 Richland County compares

Richland County ranks 6 of 7 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Newberry County16%Lexington County13%Sumter County12%Fairfield County7%Kershaw County5%Richland County5%Calhoun County0%South Carolina 19%
Data table
AreaTests ≥ 4 pCi/LTests
Newberry County16%75
Lexington County13%591
Sumter County12%42
Fairfield County7%27
Kershaw County5%60
Richland County5%671
Calhoun County0%11
South Carolina (46 counties)19%26,481

Same source as Richland County.

What it means for your home

About 1 in 20 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: 671. 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