If you have a room with two people, and both are wearing masks, and one is infected (overtly symptomatic or otherwise), the odds of the other person being infected are considerably lower than if only one of them is wearing a mask, or especially if neither are.
It obviously depends on a lot of factors, including proximity, air flow, what each person is doing, the material of the mask, how tight it is to the face, etc. But it definitely helps, even if it doesn't reduce the chance to 0.
>>11895784>Nano.... nano... a fucking bandana works with nano?Your questioning is valid, but it's more complicated. You're assuming you have a direct path between the nanoparticles, the outside world, and your face or orifices. If the particle is carried on a droplet of saliva, or mucus, or anything else, that carrier may be caught by a mask, either outbound (if the transmitter is wearing a mask) or inbound (if the receiver is wearing one).
Also, N95/99 respirators don't work on the principle of making the holes too small for viruses to pass through. They can pass through. They use other properties to make it likely that they get "stuck" before they come out of the other side of the mask:
https://www.youtube.com/watch?v=eAdanPfQdCAI don't know what research has been done on it, but I believe makeshift masks may also "catch/stick" some % of pure viroids traveling through the air, due to various properties. Probably the thicker the material, the harder it'd be to breathe through it for a long period of time, but the more likely it'd be that a viroid or a carrier of them gets stuck before it comes through the mask.
Some will make it through, but some won't. This means you may not get infected at all, and if you do, your initial viral load will be smaller, which makes it more likely that your symptoms will be less severe and that your immune system will take care of it more quickly.
