20%tests ≥ 4 pCi/L
99tests on record
1.9median pCi/L
Zone 3EPA zone (1993 prediction)

Test results in Gem County

ResultShareEPA guidance
Below 2 pCi/L55%Below EPA's levels
2 to 4 pCi/L25%Consider fixing
4 pCi/L or more20%EPA recommends fixing

What the data shows

Where Gem County sits among Idaho's 44 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 Gem County compares

Gem County ranks 6 of 8 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Adams County52%Valley County27%Ada County25%Boise County22%Washington County21%Gem County20%Canyon County11%Payette County5%Idaho 42%
Data table
AreaTests ≥ 4 pCi/LTests
Adams County52%31
Valley County27%128
Ada County25%3,030
Boise County22%58
Washington County21%67
Gem County20%99
Canyon County11%563
Payette County5%61
Idaho (44 counties)42%12,961

Same source as Gem County.

What it means for your home

About 1 in 5 results in Gem 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: 99. 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