SARS-CoV-2 is expelled and carried in respiratory droplets and stays infective for 3hrs-9days based on what it lands on ... if you can smell their breath or fart, they can infect you ... while *droplets* do get filtered out by N95 masks, the vast majority of viral particles anyone is likely to encounter are dessicated and will be stirred up and aerosolized by walking/touching/pressing/etc...
N95 masks (the ones you see many folks in the public wearing) are useful for three reasons only 1. to *partially* filter out viral laden droplets from INHALED air 2. to reduce viral particles droplets from EXHALED air and 3. primarily to physically remind you NOT TO TOUCH YOUR FACE ... the N95 masks are not airtight, they do not filter out the sub-micron, dessicated airborne viral particles and, as such, do only a little to prevent the wearer from getting infected beyond reminding them to not touch their face ... in essence - N95 masks are to prevent the WEARER from infecting others and to physically prevent the WEARER from touching their faces ... you don't have some cloak of protection when wearing these things ... give the stash you're hoarding to the local hospital - PLEASE
You'll notice that Ebola health workers don't wear N95 masks, they wear full face, air tight, sealed rebreathers - think scuba gear ... N95 masks are not "N95 respirators" ... this latter equipment is not commonly available to the public
Also, facial hair affects whether an N95 *Respirator* is going to be effective since the hair creates gaps in the mask "seal" ... this is largely moot with an N95 *mask* since it does not seal against your face in the best of circumstances
