Regardless of whether or not they work for you or at the site, employers should ensure protection of any persons on or near their worksite.
A broad interpretation of OHS statutes allows regulators across Canada to begin enforcing proceedings for workplace incidents involving non-workers, and that’s just what they’re doing.
All Canadian jurisdictions have a version of a general duty clause in their H&S legislation that requires the employer to take all reasonable precautions for the protection of workers, read more from the Canadian Occupational Safety magazine on the topic here.