Attention! The manufacturer's instructions only describe the basic procedure for patients who need ventilation for support and can still breathe independently while the mask is being changed. In my case, since the mask is necessary for life support, we have to reconnect the tube much earlier and my ventilator is never switched off.
The steps described here only serve as a basic illustration. You can find out exactly how I change masks, with lots of sexy photos of me, in the section of the same name entitled "Changing masks.
Release the lower headgear from the lower hooks of the mask frame.
With the lower head straps open, pull the head strap off over the head.