33%tests ≥ 4 pCi/L
43tests on record
2.7median pCi/L
Zone 2EPA zone (1993 prediction)

Test results in Ralls County

ResultShareEPA guidance
Below 2 pCi/L33%Below EPA's levels
2 to 4 pCi/L35%Consider fixing
4 pCi/L or more33%EPA recommends fixing

What the data shows

Where Ralls County sits among Missouri's 115 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%

How Ralls County compares

Ralls County ranks 4 of 6 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Pike County, Illinois46%Marion County42%Pike County40%Ralls County33%Audrain County30%Monroe County23%Missouri 31%
Data table
AreaTests ≥ 4 pCi/LTests
Pike County, Illinois46%108
Marion County42%282
Pike County40%35
Ralls County33%43
Audrain County30%127
Monroe County23%30
Missouri (115 counties)31%58,525

Same source as Ralls County.

What it means for your home

About 1 in 3 results in Ralls 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: 43. 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