If the OP was Canadian he should have made that clear. This US based forum allows anyone to jump in a coach with air brakes and have at it. I drive a Canadian built Prevost bus but I am not required to follow Canadian rules. I know very little about how air brakes work other than I push the pedal and the brakes stop the bus. I let Prevost handle the normal maintenance including the air dryer and brake pads. My old coach requires manual adjustment of the brakes and that is taken care of as well.
Since you have no idea what you are talking about when you point fingers at me you might want to mind your manners.
Here in the US you really DON'T need to know any more about air brakes than you would know about hydraulic or manual brakes and I will say it again, you just push the pedal to stop.
OK, on edit I should have said you need to make sure you have air pressure in the system but I would assume that most folks would at least ask "What do these gauges mean?" before driving the coach off the lot.