[pinky1417]

Two nitpicks: an FFP2 should also work pretty well with its 94% filtration capacity. Second, I assume you're in Europe, because USA-spec N95 or N100 masks would also work. Doesn't affect the point you're making.

Reason and recent scientific evidence, however, does affect your point that nothing but the highest-rated respirators prevent contraction. The FFP2/FFP3/N95/N100s of the world prevent contraction much more effectively than lower-rated masks or respirators, but it's wrong to say that other masks don't protect against this coronavirus.

Common sense suggest that homemade masks prevent the contraction of COVID, just to a substantially lower extent than the higher-end respirators. Even before the scientific studies came out showing that homemade masks could reduce contraction, it wouldn't be dumb to wear a mask for purely selfish reasons. A bandana blocks some particles. A Chinese spec KN95 is likely better. Even if the bandana only blocks 25% of particles that could cause COVID, I'd definitely wear it if it was all I had and I had to go to the grocery store.

But you don't need to take my word/logic for it. Here are a few pre-prints I found on the great medRxiv. https://www.medrxiv.org/content/10.1101/2020.04.14.20065375v... https://www.medrxiv.org/content/10.1101/2020.05.06.20093021v... https://www.medrxiv.org/content/10.1101/2020.05.07.20093864v...

[TomMarius]

I agree with everything you said except about the protection thing. I would except things that are supposed to protect me from a thing to be capable of it - a bandana, a mask, or a lower-rated respirator protect me from most droplets containing the virus, but have no capability of protecting me from the virus itself. However this is, as another commenter said, probably too much technical correctness.