Article 37 requires Management to treat "employees with dignity and respect at all times." That means referring to employees by their name, or by their job title, (sorter, preloader, etc.,) or by their revelant status (part-time, full-time, Local Sort, etc.,) depending on the situation.
Except perhaps in the Payroll Department, there is almost never a situation where an employee is to be referred to by his payroll method.
Chinese workers didn't like to be called Coolies. Dark skined people don't appreciate being called Darkies. A hard-working husband doesn't like to learn his spoiled, high-maintenance wife calls him "my Meal Ticket." And I'm sure low-level Supervisors and Managers wouldn't like upper Management or especially "Hourlies" calling them "the Saleried Help." It's demeaning.