[Yizahi]

I use self made cotton mask to go for groceries. It's garbage - it doesn't fit tightly around the face and most of the air I inhale or exhale goes through the sides unobstructed. Proper masks would be nice but unavailable everywhere and of course washing hands is a must.

[TheAdamAndChe]

It's not about protecting you from other people, it's about protecting other people from you. Many people are asymptomatic or very mildly sick, yet are able to infect other people. When you cough or wipe your nose, you risk infecting other people. The cheap mask prevents you from touching your face as much and catches heavier particles that can't curve around the bends of the facemask as easily like water and mucus.

[claudeganon]

No, it actually does protect you, just not as effectively as N-95s. That’s why hospitals are seeking out donations of homemade masks right now.

“The masks don’t do anything” story was just something floated around to prevent runs on hospital supplies. A better strategy would’ve have been to say “everyone make and wear your own masks and it will afford us some additional amount of protection.”

[slantyyz]

Dr Michael Lin, the author of that PDF on COVID that was posted here a while ago had this to say:

"A T-shirt is 79% as effective as a surgical mask. So if someone is coughing next to you and you can't escape, breathe through your shirt sleeve. Any filtration is better than none."

[1] https://twitter.com/michaelzlin/status/1241052444798279680

[Symmetry]

I wouldn't rush to assume that it was part of a deliberate deception. People assume the function of an item from its intended use all the time and surgical masks genuinely don't provide that much protection from some viruses like measles or chicken pox. I think it's just a case that "they don't protect you" being the unexamined received wisdom and people just not bothering to look at actual studies.

[claudeganon]

I wish this was true, but I saw this claim made by more than one public-facing scientist that I’m certain knows better. If we had started adopting mass mask wearing, we could have helped reduce the spread and had people geared up to make masks for frontline healthcare workers.

[downerending]

One perhaps underappreciated benefit of even a "garbage" mask is that it's a great reminder not to touch your face. That might turn out to be important.