I see bearded men in all sorts of jobs, civilian and military, that use oxygen masks, respirators, etc.
The dudes working in my company's blade and paint shops with respirators all day--almost all beards.
If they are wearing beards they are in direct violation of OSHA's respiratory protection standards. Unless they are wearing supplied air systems..
I hear SEALs occasionally SCUBA dive--beards.
Different physics, the molecular size of air vs water is what allows SCUBA to most likely fit with light to moderate beards.
Fire departments use a full face mask that is designed to provide a larger seal area compared to a nose/mouth mask.
Go on the manufacturer's sites, and they will have the data for how they meet appropriate ANSI standards.
If the "quantitative fit test" shows beards failing, is that truly representative of operational conditions?
Yes, that's the who point of the test. If it is leaking while seated for a test, it definitely is leaking during operational use.
Qualitative test allow the user to state whether they think the mask is good or not, quantitative compares air inside and outside the mask.
Some OSHA standards, such as Asbestos, state that only a quantitative test may be used.
Almost every European military--beards.
And? Some are unionized also. What's that got to do with proper fit of a respirator or O2 mask?
This is about uniformity and aesthetics
Absolutely not, it's about proper use of any safety/survivability equipment.
Any Flight Physiologists or DOSSs wish to chime in?