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Radon in Ann Arbor, Michigan

Ann Arbor, Michigan lies in Washtenaw County, which EPA places in Zone 1, highest predicted potential. Radon data is published by county, so this page reads Washtenaw County's figures.

MichiganAbout 122,233 people

What this means for you

  • Your area: EPA rates Washtenaw County, where Ann Arbor 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 8,500 radon tests reported to CDC for Washtenaw County (2008 to 2017, laboratory), 41.3% 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.

Ann Arbor, What is published

What is published for Ann Arbor

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

Washtenaw County has an EPA zone and its own CDC test figures, shown below. About 122,233 people live in Ann Arbor.

Ann Arbor, Counties

The county Ann Arbor lies in

Measured

Each county's own EPA zone and its own published CDC figures for 2008 to 2017, laboratory, 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.

Washtenaw CountyZone 1Highest predicted potential

41.3%
Reported tests at or above 4 pCi/L, 2008 to 2017, laboratory
3.2 pCi/L
Median reported result
8,500 tests
Tests reported to CDC
0
Annual years on file

The median reported pre-mitigation result for 2008 to 2017, laboratory was 3.2 pCi/L in Washtenaw 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, 2008 to 2017, laboratory.

Ann Arbor, Local resources

Local resources for Ann Arbor

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

Michigan Indoor Radon Program

Michigan Department of Environment, Great Lakes, and Energy

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

Phone
800-723-6642
Email
Radon@Michigan.gov
Licensing of radon professionals
Michigan does not license or regulate radon testing and mitigation contractors.
Visit the program's page(opens in a new tab)

Test kits

Ask the program whether it has free or discounted kits, or compare kits you can buy.

Free and low-cost kitsCompare kits

Radon professionals

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

Professionals in Michigan

Ann Arbor, Questions

Questions about radon in Ann Arbor

What radon zone is Ann Arbor in?

EPA's Map of Radon Zones classifies counties, not cities. Washtenaw 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 Ann Arbor's counties?

For 2008 to 2017, laboratory, the share of radon tests reported to CDC that were at or above 4 pCi/L was 41.3% in Washtenaw County (8,500 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 Ann Arbor?

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 Washtenaw County, the county Ann Arbor lies in.

Ann Arbor, Keep reading

Keep reading

Ann Arbor / Next steps

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