The important part is probably the behind-the-head straps.
That’s my guess too.
that seal comes from your face deforming to fit a rigid mask
Are you sure? It seems to me that even the most “rigid” masks I’ve tried are still not very hard, and with sufficiently tight straps while my skin deforms slightly the masks deform much more?
Here is a typical disposable P100 mask.
Note that this is a valved mask, so it probably wouldn’t have done well in a source control comparison.
That’s my guess too.
Are you sure? It seems to me that even the most “rigid” masks I’ve tried are still not very hard, and with sufficiently tight straps while my skin deforms slightly the masks deform much more?
Note that this is a valved mask, so it probably wouldn’t have done well in a source control comparison.