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Radon in Wausau, Wisconsin

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

WisconsinAbout 40,188 people

What this means for you

  • Your area: EPA rates Marathon County, where Wausau 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 349 radon tests reported to CDC for Marathon County (2023), 51.9% 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.

Wausau, What is published

What is published for Wausau

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 Wausau, so every radon figure on this page belongs to a county and is labelled with it. Only a test tells you about one home.

Marathon County has an EPA zone and its own CDC test figures, shown below. About 40,188 people live in Wausau.

Wausau, Counties

The county Wausau 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.

Marathon CountyZone 1Highest predicted potential

51.9%
Reported tests at or above 4 pCi/L, 2023
4.3 pCi/L
Median reported result
349 tests
Tests reported to CDC
9
Annual years on file

The median reported pre-mitigation result for 2023 was 4.3 pCi/L in Marathon 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.

Wausau, Local resources

Local resources for Wausau

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

Wausau, Questions

Questions about radon in Wausau

What radon zone is Wausau in?

EPA's Map of Radon Zones classifies counties, not cities. Marathon 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 Wausau's counties?

For 2023, the share of radon tests reported to CDC that were at or above 4 pCi/L was 51.9% in Marathon County (349 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 Wausau?

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 Marathon County, the county Wausau lies in.

Wausau, Keep reading

Keep reading

Wausau / Next steps

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