Personal Protective Equipment (PPE)
Personal protective gear has had an explosion of Development activity over the past four decades with the discovery of many toxic chemical exposure to humans in their work environment and the biological effect which unfortunately was were only identified after decades of toxic chemical exposures and much loss of life and morbidity.
The surgical masks and cloth masks now widely used to avoid droplet transmission amongst humans are an initial step which has been useful to some degree.
Respirators ,on the other hand , are protective devices designed to provide a seal such that fumes and particles are not able to enter the respiratory system
There are many kinds of respirators which people use to guard against toxic or infectious substances being breathed into their respiratory system.
The now familiar in 95 mask is an example which permits us to breeze air through a filter with very small holes which are smaller than the virus particles we wish to exclude.
People are also familiar now with the difficulties in wearing an N 95 respirator mask for prolonged periods of time. They must be tight fitting and the very small holes allowing air transmission through the mask require one to breathe in quite strongly and this is found uncomfortable by many.
N95 will not seal properly with a beard!