Author Topic: Face masks - the case against (Read 5506 times)

jeremyp · « **Reply #25 on:** October 13, 2020, 10:08:53 AM »

Quote from: Blokey McBlokeface on October 13, 2020, 10:04:16 AM

If a mask protects other people from my germs, I fail to see how it can fail to protect me from other people's germs. If it forms an effective barrier in one direction, why doesn't it in the other direction?

Because when you breathe out, the droplets containing the virus are either captured by the mask which they hit straight away or redirected upwards where they condense on your specs (at least that is how it seems to me).

When you breathe in, the air tens to come in round the sides of the mask not through it.

SteveH · « **Reply #26 on:** October 13, 2020, 10:17:19 AM »

Quote from: jeremyp on October 13, 2020, 10:08:53 AM

Because when you breathe out, the droplets containing the virus are either captured by the mask which they hit straight away or redirected upwards where they condense on your specs (at least that is how it seems to me).

When you breathe in, the air tens to come in round the sides of the mask not through it.

Why doesn't my breath go out round the sides? I remain unconvinced. They are not 100% effective, but they must logically provide some protection both to others and to the wearer.

Udayana · « **Reply #27 on:** October 13, 2020, 11:34:19 AM »

Quote from: Blokey McBlokeface on October 13, 2020, 10:04:16 AM

If a mask protects other people from my germs, I fail to see how it can fail to protect me from other people's germs. If it forms an effective barrier in one direction, why doesn't it in the other direction?

https://www.truthorfiction.com/wear-your-mask-the-urine-test-analogy-meme/

"A meme likening the purpose of coronavirus masks to protecting from a random wild urinaters accurately describes the purpose of coronavirus mask recommendations."

Aruntraveller · « **Reply #28 on:** October 13, 2020, 11:40:19 AM »

Thanks for posting that Udayana, the very same meme came to my head whilst reading this thread.

Owlswing · « **Reply #29 on:** October 13, 2020, 02:17:55 PM »

Quote from: Trentvoyager on October 13, 2020, 11:40:19 AM

Thanks for posting that Udayana, the very same meme came to my head whilst reading this thread.

An analogy the truth of which even the thickest, even the freakin' Yanks, cannot fail to see!

ad_orientem · « **Reply #30 on:** October 13, 2020, 02:55:08 PM »

Quote from: Blokey McBlokeface on October 13, 2020, 10:04:16 AM

If a mask protects other people from my germs, I fail to see how it can fail to protect me from other people's germs. If it forms an effective barrier in one direction, why doesn't it in the other direction?

Exactly.

ippy · « **Reply #31 on:** October 13, 2020, 04:48:07 PM »

Quote from: ad_orientem on October 13, 2020, 02:55:08 PM

Exactly.

I'm sure there's no 100% answer to this blasted virus but I'll go with anything that even slightly improves our chances of surviving and I'll go with Blokey Mc B on this one too.

ippy.

Aruntraveller · « **Reply #32 on:** October 13, 2020, 10:47:24 PM »

Quote from: Owlswing on October 13, 2020, 02:17:55 PM

An analogy the truth of which even the thickest, even the freakin' Yanks, cannot fail to see!

It might interest you to know that the UK and the USA are recorded as being at the same level of compliance for wearing masks in public - around 75%. So your depiction of Americans as being thick on that basis is incorrect, although viewing the evening news I can see how you might conclude that they don't comply. That, I suspect, is a fault of news organisations and their agendas rather than the fault of the people of the USA.

Incidentally, Germany usually held up as an exemplar in Covid matters only achieves 65%. Still those freakin' Krauts, eh?

Figures available here: https://en.wikipedia.org/wiki/Face_masks_during_the_COVID-19_pandemic

Outrider · « **Reply #33 on:** October 15, 2020, 10:11:25 AM »

Quote from: Blokey McBlokeface on October 13, 2020, 10:04:16 AM

If a mask protects other people from my germs, I fail to see how it can fail to protect me from other people's germs. If it forms an effective barrier in one direction, why doesn't it in the other direction?

It theoretically reduces the range of dispersal - once someone else's germs are at the front of your mask, anything you breathe in is only going to one place, but when you breathe out the mask disrupts the air flow, and limits how far your germs spread.

It's a minor effect - there is some degree of capture within the fabic, but not much - but over a large population that minor effect adds up to significant gains in absolute terms, but only a small 'percentage' difference.

O.

SteveH · « **Reply #34 on:** October 17, 2020, 05:17:34 PM »

Quote from: jeremyp on October 13, 2020, 10:08:53 AM

Because when you breathe out, the droplets containing the virus are either captured by the mask which they hit straight away or redirected upwards where they condense on your specs (at least that is how it seems to me).

When you breathe in, the air tens to come in round the sides of the mask not through it.

I noticed today, wearing a cloth mask, that when I breathed in, the material moved inwards towards my mouth and nose, s obviously most of the air is going through the mask.

Udayana · « **Reply #35 on:** October 18, 2020, 02:39:42 PM »

Quote from: Blokey McBlokeface on October 17, 2020, 05:17:34 PM

I noticed today, wearing a cloth mask, that when I breathed in, the material moved inwards towards my mouth and nose, s obviously most of the air is going through the mask.

Yes, of-course - along with any covid-19 viruses not in droplets large enough to be captured by a mask, fall to the ground, or blown away out of your immediate area. It all depends on the size of the droplets and how long small droplets can linger - the protection is not absolute but probabilistic.

SteveH · « **Reply #36 on:** October 18, 2020, 09:20:31 PM »

Quote from: Udayana on October 18, 2020, 02:39:42 PM

Yes, of-course - along with any covid-19 viruses not in droplets large enough to be captured by a mask, fall to the ground, or blown away out of your immediate area. It all depends on the size of the droplets and how long small droplets can linger - the protection is not absolute but probabilistic.

I know they're not 100% effective, but if they are effective at all, they must be so in both directions.

Outrider · « **Reply #37 on:** October 19, 2020, 08:43:06 AM »

Quote from: Blokey McBlokeface on October 18, 2020, 09:20:31 PM

I know they're not 100% effective, but if they are effective at all, they must be so in both directions.

Technically, yes, but to vastly differing degrees. Part of the effect 'outbound' is the fact that the droplets are dispersed more - passing through the cloth causes turbulence which both widens and shortens the dispersal pattern. BY contrast, on the in-breath, your physique tends to channel everything one way, and although the mask will capture a few tiny element most will still pass through, and if everyone else is wearing masks then the majority of particles too big to pass through your mask have already been caught on theirs.

O.

SteveH · « **Reply #38 on:** October 19, 2020, 09:50:38 AM »

Quote from: Outrider on October 19, 2020, 08:43:06 AM

Technically, yes, but to vastly differing degrees. Part of the effect 'outbound' is the fact that the droplets are dispersed more - passing through the cloth causes turbulence which both widens and shortens the dispersal pattern. BY contrast, on the in-breath, your physique tends to channel everything one way, and although the mask will capture a few tiny element most will still pass through, and if everyone else is wearing masks then the majority of particles too big to pass through your mask have already been caught on theirs.

O.

Thank you - a sensible explanation, at last, of why they are much more effective at protecting others than the wearer! That's all I wanted, because, while it's easy to understand when explained, it isn't obvious.

jeremyp · « **Reply #39 on:** October 19, 2020, 10:50:23 AM »

Quote from: Blokey McBlokeface on October 17, 2020, 05:17:34 PM

I noticed today, wearing a cloth mask, that when I breathed in, the material moved inwards towards my mouth and nose, s obviously most of the air is going through the mask.

No. Obviously it is not.

The moving in is caused by a difference in pressure between the two sides. i.e. the air molecules are hitting the mask and bouncing off, not going straight through.

If the mask was made of fishnet would it move in as much as if it were made of polythene?

Dicky Underpants · « **Reply #40 on:** October 21, 2020, 05:10:28 PM »

Quote from: Outrider on October 19, 2020, 08:43:06 AM

Technically, yes, but to vastly differing degrees. Part of the effect 'outbound' is the fact that the droplets are dispersed more - passing through the cloth causes turbulence which both widens and shortens the dispersal pattern. BY contrast, on the in-breath, your physique tends to channel everything one way, and although the mask will capture a few tiny element most will still pass through, and if everyone else is wearing masks then the majority of particles too big to pass through your mask have already been caught on theirs.

O.

May I also thank you for that helpful and lucid explanation.

jeremyp · « **Reply #41 on:** October 22, 2020, 11:42:19 PM »

Here is a Slow Mo Guys video about wearing masks. I think it shuts down the argument against mask wearing completely.

https://youtu.be/gZ66wJFD3bs

Also there’s an interview with a special guest.

Owlswing · « **Reply #42 on:** October 23, 2020, 12:26:44 AM »

Quote from: jeremyp on October 22, 2020, 11:42:19 PM

Here is a Slow Mo Guys video about wearing masks. I think it shuts down the argument against masks wearing completely.

https://youtu.be/gZ66wJFD3bs

Also, there’s an interview with a special guest.

If you do not wear a mask, watch this video; if you do wear one, tell everyone you know who doesn't to watch it!

Owlswing · « **Reply #43 on:** October 23, 2020, 02:20:52 AM »

Quote from: Beyoncé Castle on October 19, 2020, 09:50:38 AM

Thank you - a sensible explanation, at last, of why they are much more effective at protecting others than the wearer! That's all I wanted, because, while it's easy to understand when explained, it isn't obvious.

You want obvious? Watch the video in #41!