32%tests ≥ 4 pCi/L
385tests on record
2.3median pCi/L
Zone 2EPA zone (1993 prediction)

Test results in Belknap County

ResultShareEPA guidance
Below 2 pCi/L43%Below EPA's levels
2 to 4 pCi/L25%Consider fixing
4 pCi/L or more32%EPA recommends fixing

What the data shows

Where Belknap County sits among New Hampshire's 10 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 Belknap County compares

Belknap County ranks 3 of 5 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Carroll County48%Strafford County43%Belknap County32%Merrimack County31%Grafton County26%New Hampshire 35%
Data table
AreaTests ≥ 4 pCi/LTests
Carroll County48%425
Strafford County43%870
Belknap County32%385
Merrimack County31%1,179
Grafton County26%1,579
New Hampshire (10 counties)35%15,608

Same source as Belknap County.

What it means for your home

About 1 in 3 results in Belknap 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: 385. 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