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Radon in Westerville, Ohio

Westerville, Ohio spans 2 counties, Delaware County and Franklin County. Radon data is published by county, so this page sets their figures side by side.

OhioAbout 38,165 people

What this means for you

  • Your area: Westerville lies in 2 counties. EPA rates Delaware County Zone 1 and Franklin County Zone 1, where Zone 1 is the highest of its three radon zones. Zones are predictions for whole counties, and homes with elevated levels occur in all three zones.
  • Local tests: For 2008 to 2017, the share of radon tests reported to CDC that were at or above 4 pCi/L was 72.2% in Delaware County (3,730 tests) and 71.9% in Franklin County (16,142 tests). EPA's action level is 4 pCi/L.
  • 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.

Westerville, What is published

What is published for Westerville

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

Each county has its own CDC test figures, shown below side by side. About 38,165 people live in Westerville.

Westerville, Counties

Westerville's counties, side by side

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.

  • Delaware County
    EPA zone
    Zone 1: Highest predicted potential
    At or above 4 pCi/L
    72.2%
    Median result
    6.4 pCi/L
    Tests reported
    3,730 tests
    Annual years on file
    0
  • Franklin County
    EPA zone
    Zone 1: Highest predicted potential
    At or above 4 pCi/L
    71.9%
    Median result
    6.8 pCi/L
    Tests reported
    16,142 tests
    Annual years on file
    0
The counties Westerville lies in, each with its own EPA zone and its own published CDC figures for 2008 to 2017, laboratory
CountyEPA zoneReported tests at or above 4 pCi/LMedian reported resultTests reportedAnnual years on file
Delaware CountyZone 1: Highest predicted potential72.2%6.4 pCi/L3,730 tests0
Franklin CountyZone 1: Highest predicted potential71.9%6.8 pCi/L16,142 tests0

The median reported pre-mitigation result for 2008 to 2017, laboratory was 6.4 pCi/L in Delaware County and 6.8 pCi/L in Franklin 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.

Westerville, Local resources

Local resources for Westerville

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

Radon Education and Licensing Program

Ohio Department of Health

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

Phone
614-728-0272
Email
indoor.radon@odh.ohio.gov
Licensing of radon professionals
This program licenses companies and persons directly involved with the radon testing and mitigation industry.
Visit the program's page(opens in a new tab)

Test kits

The program says: Free radon test kits are available for Ohio homeowners.

Free and low-cost kitsCompare kits

Radon professionals

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

Professionals in Ohio

Westerville, Questions

Questions about radon in Westerville

What radon zone is Westerville in?

EPA's Map of Radon Zones classifies counties, not cities. Delaware County and Franklin County are 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 Westerville's counties?

For 2008 to 2017, laboratory, the share of radon tests reported to CDC that were at or above 4 pCi/L was 72.2% in Delaware County (3,730 tests) and 71.9% in Franklin County (16,142 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 Westerville?

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 Delaware County and Franklin County, the counties Westerville lies in.

Westerville, Keep reading

Keep reading

Westerville / Next steps

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