66%tests ≥ 4 pCi/L
1,071tests on record
6.2median pCi/L
Zone 1EPA zone (1993 prediction)

Test results in Winneshiek County

ResultShareEPA guidance
Below 2 pCi/L17%Below EPA's levels
2 to 4 pCi/L17%Consider fixing
4 pCi/L or more66%EPA recommends fixing

What the data shows

Where Winneshiek County sits among Iowa's 99 counties with dataEach dot is a county's share of tests at or above 4 pCi/L · Iowa radon test results from laboratories, 2008–2017
0%20%40%60%80%

How Winneshiek County compares

Winneshiek County ranks 2 of 6 among its neighboursShare of tests at or above 4 pCi/L · Iowa radon test results from laboratories, 2008–2017 · whisker: 95% range
Allamakee County73%Winneshiek County66%Fayette County63%Clayton County63%Howard County61%Chickasaw County59%Iowa 58%
Data table
AreaTests ≥ 4 pCi/LTests
Allamakee County73%492
Winneshiek County66%1,071
Fayette County63%746
Clayton County63%310
Howard County61%388
Chickasaw County59%498
Iowa (99 counties)58%95,245

Same source as Winneshiek County. Other bordering counties: Fillmore County, Minnesota, Houston County, Minnesota.

What it means for your home

More than half of all results in Winneshiek 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 →

Iowa licenses radon mitigators. Source

Buying or selling here

Iowa sellers complete the Real Estate Commission's disclosure statement and must give buyers the "Iowa Radon Home-Buyers and Sellers Fact Sheet" (Iowa Admin. Code 193E). Source

Checked against the official text on 2026-11-03. Not legal advice.

About this data

Source: Iowa radon test results from laboratories (CDC Environmental Public Health Tracking Network). Period: 2008–2017. Tests: 1,071. 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