· Indoor radon
Radon atlas covers 117 CMA and regional communities in 2026
The highest indoor radon ranking now spans 117 places drawn from Health Canada survey geographies, with prairie cities still leading the chart.
By OpenStats research desk
The 2026 highest indoor radon ranking now covers 117 CMA and regional proxy communities drawn from Health Canada survey geographies. Prairie cities remain at the top of the chart: Winnipeg, Regina, and Saskatoon continue to show elevated long-term means relative to many coastal and Great Lakes centres, with Calgary also in the national conversation.
What the coverage note means
Coverage here means the ranking and the radon atlas publish a page when Health Canada survey data can be matched to a census metropolitan area or a documented regional proxy. Direct municipal microdata is rare for radon; most hometown pages are regional estimates and are labeled that way so readers can judge confidence.
Rankings flip the scale so rank 1 is the highest mean indoor radon. Figures are comparative community context from the survey, not a measurement of any single home. Health Canada's guidance still points households toward testing living areas, especially in basements and ground-contact rooms.
Where to go next
Open a prairie hometown chart on this hub, then the radon atlas city page for the survey mean and the share of homes above 200 Bq/m³ where the source supports it. Background reading sits in the indoor radon guide. This article is informational. For health decisions, follow Health Canada guidance and a licensed professional.
Data tiers, corrections, and advertising disclosure are spelled out under editorial standards. Named sources live on the data sources page.