There are two primary methods of transmission, they said. The first is via droplets a carrier expels, which are about one-third the size of a human hair but still large enough that we can see them. Masks create an effective barrier against droplets.
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Transmission by aerosol particles
The second major transmission method is via the aerosol particles we expel when we talk. Those are about 1/100th the size of a human hair and are more difficult to defend against. Social distancing and staying outdoors, where there is more air flow, are helpful, Blumberg and Ristenpart said.
“Studies in laboratory conditions now show the virus stays alive in aerosol form with a half-life on the scale of hours. It persists in the air,” Ristenpart said. “That’s why you want to be outdoors for any social situations if possible. The good air flow will disperse the virus. If you are indoors, think about opening the windows. You want as much fresh air as possible.”
The mask(whatever type) doesn't matter if it doesn't have an airtight seal around the entire airway, and have a filter system that stops all particles down to .1 microns(?) both coming and going. Surgical masks, n95 masks, cloth masks, your favorite face diaper can't do that. So unless you properly use a true, certified airtight face sealing respirator whether it be industrial or military, and protect your eyes from ingress, and sterilize everything every time you take it off/put it on before entering/leaving your home/office school etc. etc. ad nausium you ain't gonna stop jack.....and that's science.
“Some ideas are so stupid that only intellectuals believe them.” ― G. Orwell
"Why can't men kill big game with the same cartridges women and kids use?" _Eileen Clarke
"Unjust authority confers no obligation of obedience." - Alexander Hamilton
