Paper: Occupational exposure limits in Canada: A comparison across the provinces and territories

Author(s) and Affiliation(s):
Cheryl E. Peters, University of British Columbia
Daniel Sarkany, University of British Columbia
Paul A. Demers, University of British Columbia
Day/Time: Friday at 13:30
Room: St. David Room, 3rd Floor

Canada’s occupational exposure regulations vary by jurisdiction, which could lead to regional differences in workers’ exposure to hazardous substances. This has implications for exposure assessment, as well as for human health. The objectives of this project are to perform a survey of threshold limit values for a set of high priority carcinogens (selected for CAREX Canada, a national exposure surveillance project), and qualitatively review differences between the provinces/territories, highlighting where improvements could be made.


We located and reviewed the occupational exposure regulations for the jurisdictions covering Canadian workers (10 provinces and 3 territories, and the Canada Labour Code for federally legislated workers). For comparison, we also reviewed the ACGIH recommended standards, and a select group of international exposure limits known for being especially protective of worker health. We summarized the organizations responsible for setting occupational limits and reviewed their legislation for comparison and contrast. We categorized jurisdictions with respect to how flexible and current their regulations were (i.e. fixed in time, or updated with ACGIH yearly), how much they varied from accepted ACGIH standards, and where they provided exceptions for specific substances. We also summarized information on substances where a wide variation in occupational exposure limits occurred across Canadian jurisdictions.


Canadian jurisdictions regulate occupational exposure limits very differently. Responsibility is held by a variety of institutions and transparency about how limits are set, and even what those limits are, differed regionally. The most striking regulatory finding was that of the 14 Canadian jurisdictions, only four (29%) automatically adopt widely accepted ACGIH recommended standards yearly (MB, NL, PE, NS). Several other provinces adopted ACGIH regulations for a fixed year (i.e. 1997 for New Brunswick) and then have, in some cases, applied updates for specific substances at various times since. Some substances (e.g. formaldehyde) have very different exposure limits depending on jurisdiction.


Regional variation in occupational exposure limits exists in Canada, and sometimes within a single province. This is likely to lead to differences in exposure levels experienced by Canadian workers. This is of particular importance for human health, and also for exposure assessment at a national level (such as the work of CAREX Canada). Differences in exposure limits were due to bureaucratic barriers (i.e. legislation not designed for flexibility), lack of resources (i.e. the territories), and industry pressure (i.e. for formaldehyde). We recommend that a national standard for occupational exposure limits would be the best practice for protecting the health of Canadian workers.