n95's have guaranteed penetration protection and make a conformable seal around your face. That doesn't mean a high density face mask can't protect you against frontal respiratory droplets, especially against a virus that hates absorbing surfaces.
https://www.calpaclab.com/blog/does-your-mask-work-against-coronavirus/
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Its has nice imagery but does not discuss the main player in filters, the triboelectric effect, two dissimilar materials rubbing to generate static charge. This is often the minimum two layers in a medical mask. In Africa (2nd time I lived there, years after the ranger stuff) a friend's kid had pollution sensitivities issues and I had to make decent filters similar to merv13 furnace filters. I achieved it by spray doping non-woven/blast spun polyurethane fabric with a common mineral.
Its an interesting area filter design. I have built a dozen different kinds of propotype filters. Of course a basic particle detector is needed however when you get a room down to a below 70 or so under 0.3um per cubic, you can literally just smell it, or the absence rather.