Live data from Hacker News

Low-cost measurement of facemask efficacy for filtering expelled droplets

advances.sciencemag.org

41–50 of 92 posts

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#43
The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media.

Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/

And here is a study that warns that wearing masks leads to cardiac damage:

https://link.springer.com/article/10.1007/s00392-020-01704-y

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#44
post #16

Earlier quoted context omitted.

You touch your face more when adjusting the mask so if it's not efficient enough it may be a net negative. Edit: This is one of the main reason the Scandinavian countries recommend against _all_ mask use (including N95) so not sure why I'm getting downvoted for merely saying an inefficient mask could have that problem.

> You touch your face more when adjusting the mask so if it's not efficient enough it may be a net negative. Keep hand sanitizer in your pocket. Whenever you touch the mask, sanitize your hands. Both before you touch (in case you touched a COVID19 infected surface, you don't want to add COVID19 to the mask), and after you touch (in case your mask prevented COVID19 from entering your lungs, you don't want to contamina…

Yes, of course but that's the point. That people are unable follow correct mask usage and get sloppy, especially over time.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#45
post #43

The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media. Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ And here is a study that warns that wearing masks leads to car…

From first study: "The null hypothesis is that there is no difference between medical masks and cloth masks. ... The control arm was ‘standard practice’, which comprised mask use in a high proportion of participants [NOT "mask free"]." -- this means "increase relative to surgical masks", not relative to no mask.

Second study is only N95s. Just don't wear an N95 if you need more air for aerobic capacity. The OP study shows that they're not _that_ much better than surgical masks anyway.

But hey believe what you want to believe.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#46
post #23

Earlier quoted context omitted.

I've seen that idea being tossed around, but are there any sort of studies showing that the increased face touching can indeed make the virus spread more than not wearing masks? It's a geniune question, I'd like to see studies related to that. For me, it's not really obvious that more face touching (even if that happens in significant numbers across the population), causes the virus to spread more than it would have…

I think the reason that various authorities advised against masks is political - there simply weren't enough and to direct the supply to clinical workers.

That was a colossal mistake. Not only have they ruined their credibility in this pandemic but they've guaranteed that there will be panic buying during all future pandemics. It was a one-time weapon that provided marginal benefit and terrible long term consequences that go far beyond contagious diseases. Don't be surprised if anti-vaxxers use this incident for decades to come as proof that health authorities lie.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#47
post #16

Earlier quoted context omitted.

I think the broader point is one that still stands: wearing literally anything over your nose and mouth is shown, by this study, to cut droplet by at least 50%. Even the cotton varieties cut it from 70% to 90%. So...people need to just slap something over their two air exchanging orifices on their faces before leaving the house and contribute to the our greater health. You're right about the differences in effectiven…

You touch your face more when adjusting the mask so if it's not efficient enough it may be a net negative. Edit: This is one of the main reason the Scandinavian countries recommend against _all_ mask use (including N95) so not sure why I'm getting downvoted for merely saying an inefficient mask could have that problem.

[deleted]

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#48
post #44

Earlier quoted context omitted.

> You touch your face more when adjusting the mask so if it's not efficient enough it may be a net negative. Keep hand sanitizer in your pocket. Whenever you touch the mask, sanitize your hands. Both before you touch (in case you touched a COVID19 infected surface, you don't want to add COVID19 to the mask), and after you touch (in case your mask prevented COVID19 from entering your lungs, you don't want to contamina…

Yes, of course but that's the point. That people are unable follow correct mask usage and get sloppy, especially over time.

But why do you think that?

The more you practice something, the better you get at it. Assuming people to be 100% noobs at masks for months is a bit pessimistic.

It's easier today to use hand sanitizer with masks than months ago. In my experience anyway.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#49
post #43

The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media. Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ And here is a study that warns that wearing masks leads to car…

We’ve also had studies which claim something along the line of ”Apples cause cancer” and the truth is that it happens only under some certain rare conditions and even then one might have 0.01% chance of increasing their chance to get a cancer by 0.1%. But hey, that’s an increase in possibility nevertheless!

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#50
post #43

The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media. Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ And here is a study that warns that wearing masks leads to car…

The question is whether I trust your "survey" or the CDC's recommendation.

But also, in both cases based on a quick skim it seems to me like you're misrepresenting the studies. In the first study, the control was "normal practice" which included mask use. In the second study, I see no claims about cardiac damage; I understand it to say that masks make it harder to breathe, which is useful information but not very surprising.

Post reply on HN