1. I can expand on any topic I choose; as you can and have done on this one.
2. The reason this has turned into a furball is b/c you simply don't have the integrity to state, "Gee. I learned something." You agreed with Jetpilot's statement: The pilots mask forces oxygen into the lungs under pressure allowing absorbtion by the body. Wrong!! A diluter demand mask DOES NOT do this. Period. So, instead you choose to redirect and continue the argument.
3. You don't have a clue what pressure breathing is, and you admit you haven't done it. Maybe you should think about that for a moment. What's the diff? The masks look the same...Could it be DELIVery Pressure???
My response was:
There are two types of O2 masks for cockpit use:
Pressure demand - these masks are typically used on high g capable, military a/c. In use, the O2 is supplied at pressures that actually interfere with speaking. In other words, much more than the slight over pressure of the second mask:
Diluter demand - most common on airliners and business a/c. Typ has 3 positions: Normal, 100% and Emergency. Normal will dilute the O2 w/ambient air up to a specific pressure alt, above which 100% O2 is delv'd. 100% delivers, of course, 100% O2 even at lower alts. Both "normal" and "100%" positions only provide flow when a breath is drawn. "Emergency" provides continuous flow, 100% O2 (ie very slight positive pressure) in order to clear the mask/goggles if smoke is present. A diluter demand mask WILL NOT force O2 into the lungs.
To which Bellerophon and FredT strongly concurred. As Bellerophon and I both stated, if you've ever used a pressure demand mask, you'd know the distinction, which makes the difference b/t the two types blatantly clear. The fact that you still think that a diluter demand mask is in ANY way pressure breathing, or has any impact on human respiration donwstream of the nose, indicates you haven't experienced the distinction and are ignorant of the difference. Yet you argue.
So try this, and report the results:
Go sit in your seat. Put on your mask, and try to let it force air into your lungs. Talking or not. Stand/sit; whatever. What you'll find is, with a diluter demand mask, no matter what you do,
*****until you decide to INHALE (conciously or sub conciously!), NO O2 will get to your lungs. The mask WILL NOT do it FOR YOU.*****
That would be PResure Breathing, and that is the distinction you have missed in stellar fashion.