The 2024 Cross Canada Radon Report compiled data on average household radon levels across the six Canadian metropolitan areas whose populations are at least 1 million people. Collectively, these six urban areas are home to 17.52 million residents of Canada or nearly half of the entire population. The information below is ranked in order of largest to smallest population and encompasses the broader metropolitan areas.

Toronto, Ontario, has a population of approximately 6.2 million. The average radon level for a Toronto area residential building is 43.0 Bq/m³.

● KEY FINDING = 1 in 22 properties in the Toronto Metro Area are above 200 Bq/m³

Montréal, Quebec, has a population of approximately 4.3 million. The average radon level for a Montreal area residential building is 82.4 Bq/m³.

● KEY FINDING = 1 in 5 properties in the Montréal Metro Area are above 200 Bq/m³

Vancouver, British Columbia, has a population of approximately 2.6 million. The average radon level for a Vancouver area residential building is 17.1 Bq/m³.

● KEY FINDING = 1 in 113 properties in the Vancouver Metro Area are above 200 Bq/m³

Ottawa–Gatineau, Ontario, has a population of approximately 1.5 million. The average radon level for an Ottawa–Gatineau area residential building is 85.9 Bq/m³.

● KEY FINDING = 1 in 6 properties in the Ottawa–Gatineau Metro Area are above 200 Bq/m³

Calgary, Alberta, has a population of approximately 1.5 million. The average radon level for a Calgary area residential building is 102.5 Bq/m³.

● KEY FINDING = 1 in 6 properties in the Calgary Metro Area above 200 Bq/m³

Edmonton, Alberta, has a population of approximately 1.4 million. The average radon level for an Edmonton area residential building is 106.4 Bq/m³.

● KEY FINDING = 1 in 6 properties in the Edmonton Metro Area are above 200 Bq/m³

The Cross Canada Radon Survey is a comprehensive national study conducted to assess radon levels in Canadian residential properties. The survey aims to provide data that informs public health initiatives and policies to reduce radon exposure and its associated health risks. 

The report was funded by the Canadian Institutes of Health Research Healthy Cities Research Initiative, Health Canada, the Alberta Real Estate Foundation and the Canadian Cancer Society.