JMHO, but if you make the mask material so thick and impervious that air won’t flow relatively easily through it, the aspirations of the wearer will merely move the air AROUND the mask, through any available opening at the nose, etc., and there will be no filtering taking place at all. And then, as Archie Bunker would say, “What’s the pernt?”
Right. If you have ever been fit tested for a respirator, they have you move your mouth in a exaggerated way, jump up and down, talk, nod vigorously to check for leaks. Also, wearing one for a long time is very tiring.
At work we have to wear a mask when outside of the office or cubicle. One worker has a beard that looks loke a cross between Amish and Mountain Man. Unless his beard has some type of antiviral properties, that mask does nothing except filter a sneeze.
We got a whole list of instructions about cleaning hands before and after putting on and taking off the mask, how to store it and how to wash it daily. It looked like the suiting up scenes from The Hot Zone. I have seen no one follow those instructions.