[dragontamer]

> Also, don’t forget that in medical facilities N95 masks are fitted specifically to individuals.

Lets not over-dramaticize N95 masks. An N95 mask is just 95% effective. Its not N99 or N100.

N95 is the relatively cheap and disposable mask. Its "custom fit seal" is the little metal bar that you push down on your nose.

Here is 3M's official fitting video. Its actually not very hard to use: https://www.youtube.com/watch?v=05wyH1-mLGk

Then elastic bands shove the mask against your face, forming an airtight seal. This can be effectively replicated with a decent hand-made mask solution (although the filtration of a hand-made DIY mask is much much worse, and completely untested compared to N95 designs)

Given the fact that we're in an N95 mask shortage situation, I think DIY home-made masks are the only solution for the general public. It just takes some scissors and a T-Shirt to make.