8%tests ≥ 4 pCi/L
289tests on record
1.0median pCi/L
Zone 3EPA zone (1993 prediction)

Test results in Collin County

ResultShareEPA guidance
Below 2 pCi/L81%Below EPA's levels
2 to 4 pCi/L12%Consider fixing
4 pCi/L or more8%EPA recommends fixing

What the data shows

Where Collin County sits among Texas's 138 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%100%

How Collin County compares

Collin County ranks 4 of 7 among its neighboursShare of tests at or above 4 pCi/L · Radon test results from laboratories, 2008–2017 · whisker: 95% range
Hunt County25%Rockwall County19%Dallas County8%Collin County8%Denton County7%Grayson County5%Fannin County0%Texas 10%
Data table
AreaTests ≥ 4 pCi/LTests
Hunt County25%4
Rockwall County19%16
Dallas County8%728
Collin County8%289
Denton County7%192
Grayson County5%20
Fannin County0%1
Texas (138 counties)10%4,615

Same source as Collin County.

What it means for your home

About 1 in 13 results in Collin 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: 289. 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