Originally Posted by
Flight Alloy
No mask can work as a 'pressurized' mask, aka delivering more pressure to the lungs than ambient, ..... pressurized breathing is only possible with suits that also pressurize the chest area to the same pressure as the breathed gas
TBH I'm struggling to reconcile that statement with the practical training in pressure breathing that I and I'm sure some others here with an ex-military flying background will have experienced in the past.
It certainly is an interesting sensation, but as long as the differential isn't too excessive a pressure suit is not required, certainly not if you are going to only be pressure breathing for a short period of time.....