I did want to say that through the jurisprudence they actually have somewhat defined what a safety sensitive position is. It's:
A safety-sensitive job can be characterized as one in which incapacity due to drug or alcohol impairment could result in direct and significant risk of injury to the employee, others or the environment.
You have to consider that in workplaces, you have large workplaces, small workplaces, medium-sized workplaces, unionized and non-unionized ones. I think what's at the core of this, in determining what is a safety sensitive position, is really the tenet of the occupational health and safety regimes in Canada, which is that dialogue between the employer and employees to be able to determine what the hazards are in the workplace. In doing so, you would be defining what some of those safety sensitive positions are and what measures need to be taken to reduce and mitigate those risks in the workplace.
Having a definition that runs across all workplaces doesn't work. You need to have some ability, some flexibility, to respond to the variety of different types of work, workplaces, and sizes of workplaces.