31%tests ≥ 4 pCi/L
1,600tests on record
2.2median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Middlesex County

ResultShareEPA guidance
Below 2 pCi/L46%Below EPA's levels
2 to 4 pCi/L24%Consider fixing
4 pCi/L or more31%EPA recommends fixing

What the data shows

How Middlesex County compares

Middlesex County has the highest 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
Middlesex County31%New London County28%New Haven County26%Hartford County21%Suffolk County, New York8%Connecticut 26%
Data table
AreaTests ≥ 4 pCi/LTests
Middlesex County31%1,600
New London County28%2,081
New Haven County26%5,084
Hartford County21%4,918
Suffolk County, New York8%551
Connecticut (8 counties)26%25,572

Same source as Middlesex County.

What it means for your home

About 1 in 3 results in Middlesex 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.

Prefer a digital monitor? See Airthings radon monitors, or enter code radonbycounty-10OFF at their discount store for 10% off.

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: 1,600. 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