DreamWear FFM - technical question

[Arik]

Hi Guys,
 
I’m using the DreamWear FFM for about a week. So far so good.
The way I understand how the mask is functioning, the following happens when I breath via my mouth:
1.      Mouth Inhale phase- atmospheric air is coming from outside through the two little “windows” on both sides of the cushion.
2.      Mouth Exhale phase – the two little “windows” are closed by plastic valves and the exhaled air is pushed to other “outlets” of the mask (mainly back to the machine).
 
See attached image of the cushion and the “window” I’m talking about.
 
Does this makes sense? Doesn’t it affect the various calculations?
Thanks,

[KobeT]

I'm not an expert but I think you have it backwards.

[edfreeman]

It isn't supposed to work the way you described. Once the machine pressurizes the mask, those valves remain closed for both inhale and exhale.