Skip to content
RADON411
$5

County radon report

Get it

Locations and reports

Radon in Madison, Wisconsin

Madison, Wisconsin lies in Dane County, which EPA places in Zone 1, highest predicted potential. Radon data is published by county, so this page reads Dane County's figures.

WisconsinAbout 286,233 people

What this means for you

  • Your area: EPA rates Dane County, where Madison is, Zone 1, the highest of its three radon zones. That is a prediction for the whole county, and homes with elevated levels occur in all three zones.
  • Local tests: Of 2,887 radon tests reported to CDC for Dane County (2023), 34.9% were at or above 4 pCi/L, EPA's action level.
  • Your home: The only way to know your home’s level is to test it.
How to testFind a certified tester

pCi/L (picocuries per liter) is the unit radon is measured in. EPA recommends fixing a home at 4 pCi/L or above, its action level.

Madison, What is published

What is published for Madison

Information:

Radon data is published by county, not by city

Radon data is published by county, not by city. EPA assigns radon zones to counties, and CDC publishes radon test figures by county. Neither publishes a figure for Madison, so every radon figure on this page belongs to a county and is labelled with it. Only a test tells you about one home.

Dane County has an EPA zone and its own CDC test figures, shown below. About 286,233 people live in Madison.

Madison, Counties

The county Madison lies in

Measured

Each county's own EPA zone and its own published CDC figures for 2023, the newest period any of them has. A county without a figure for that period is shown without one, never with a figure from another year.

Dane CountyZone 1Highest predicted potential

34.9%
Reported tests at or above 4 pCi/L, 2023
2.5 pCi/L
Median reported result
2,887 tests
Tests reported to CDC
9
Annual years on file

The median reported pre-mitigation result for 2023 was 2.5 pCi/L in Dane County.

CDC counts radon tests that were reported to it, not homes, and figures from few tests can swing widely from year to year. Each county’s report has its full history.

Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2023.

Madison, Local resources

Local resources for Madison

Who to ask in Wisconsin: the state's radon program, test kits and professionals.

Wisconsin's radon program

Wisconsin Department of Health Services

Wisconsin’s radon program answers questions about testing, mitigation and the rules where you live.

Phone
1-888-569-7236
Email
DHSRadon@dhs.wisconsin.gov
Licensing of radon professionals
The State of Wisconsin does not require contractors performing radon measurement or mitigation work to be state licensed or nationally certified.
Visit the program's page(opens in a new tab)

Test kits

The program says: We recommend starting with your regional Radon Information Center since many centers provide test kits for free or reduced cost, and often with laboratory fees covered.

Free and low-cost kitsCompare kits

Radon professionals

Radon testers and mitigators in Wisconsin, each with how its listing was checked.

Professionals in Wisconsin

Madison, Questions

Questions about radon in Madison

What radon zone is Madison in?

EPA's Map of Radon Zones classifies counties, not cities. Dane County is in Zone 1 (highest predicted potential). A zone is a prediction for a whole county and never tells you the level in one home.

How many radon tests come back high in Madison's counties?

For 2023, the share of radon tests reported to CDC that were at or above 4 pCi/L was 34.9% in Dane County (2,887 tests). Each is that county's own figure, counting tests reported to CDC, not homes. Radon411 does not average or combine them into a figure for the city.

Should I test my home in Madison?

Yes. Testing is the only way to know the radon level in a specific building. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. How to test a home.

The answers use the published figures of Dane County, the county Madison lies in.

Madison, Keep reading

Keep reading

Madison / Next steps

What to do next