Part II of the Canada Labour Code deals with occupational health and safety. It applies to both the federal private sector and the federal public sector. Canada Post's unions usually negotiate to incorporate all those provisions into the collective agreement so that they can have them enforced at rights arbitrations through the grievance process. Usually, for example, the Canadian Union of Postal Workers has been successful in negotiating additional guarantees over and above the standards in part II of the Canada Labour Code.
I see the analogy.