Radon data & sources

Every displayed statistic traces to a public source with a reporting period and available sample context. Current result coverage comes from Pennsylvania, Michigan, Minnesota, Wisconsin, Iowa, Colorado, and Washington. Counties in 40 other states show laboratory test results from the CDC Tracking Network.

Sources

SourceGeographyPeriodRefreshLicense
Pennsylvania Department of Environmental ProtectionCounty1986–2026Checked for source updatesPublic Domain
Michigan Department of Environment, Great Lakes, and EnergyCounty (summed from ZIP codes)About 2016–2026Checked for source updatesMichigan public data
Minnesota Department of HealthCounty2016–2025Checked for source updatesMinnesota public data
Wisconsin Department of Health ServicesCounty2005–2017Checked for source updatesWisconsin public data
CDC Environmental Public Health Tracking Network (laboratory tests: Iowa and 40 other states)County2008–2017Checked for source updatesPublic Domain
Colorado Department of Public Health and EnvironmentCounty2005–2025Checked for source updatesCC0
Washington State Department of Health (Washington Tracking Network)County2000–2025Checked for source updatesWashington public data

Free CSV downloads

Pennsylvania's source data is Public Domain, Michigan's carries no use restrictions, and Colorado's is CC0 licensed. Minnesota provides a public data download through its health data portal. Download packaging is not yet available on this site; use thePennsylvania,Michigan,Minnesota, andColorado county directories to review the published statistics and attribution.