
I'm one of 100 experts urging governors to require public mask-wearing - teaman2000
https://theconversation.com/masks-help-stop-the-spread-of-coronavirus-the-science-is-simple-and-im-one-of-100-experts-urging-governors-to-require-public-mask-wearing-138507
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nabla9
VTT-research has tested different mask fabrics and made simulations of the
spread

With mask: [https://youtu.be/blpit-6A7Yo](https://youtu.be/blpit-6A7Yo) (red
is dry particles, blue is droplets)

Without mask: [https://youtu.be/HsGJlANzeq8](https://youtu.be/HsGJlANzeq8)

Tests re-affirm the existing conclusion that non-medical mask-wearing helps
from spreading the disease but is not very effective in protect the wearer.

The best available masks are made of microfiber and can filter up to 70% of
particles smaller than 2.5 micrometers. Conventional garment fabrics filter
20-45% of particles smaller than 0.65-3.3 microns in size, while FFP2 shields
96% and FFP3 99% of particles up to 0.35 micrometers. This means that a user
of fabric masks will receive several times the dose of viruses under exposed
conditions compared to a user of professional respirators.

From conventional fabrics microfiber mask is best, second is polyester, cotton
is the worst. One should wash them in hot water (90 celsius) after each use or
throw them away.

source (in Finnish):

[https://www.vttresearch.com/sites/default/files/2020-05/Medi...](https://www.vttresearch.com/sites/default/files/2020-05/Mediainfo14052020-kangasmaski-
simulaatio-teollinentuotanto.pdf)

[https://www.vttresearch.com/fi/uutiset-ja-
tarinat/kangasmask...](https://www.vttresearch.com/fi/uutiset-ja-
tarinat/kangasmaski-ei-suojaa-kayttajaansa-koronavirukselta-mutta-voi-suojata-
muita)

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2rsf
That's a good lesson in data science (the author is one). He has all the
numbers right but did he forget some things ?

I didn't see anything about re-usability of the masks (no one has an endless
stash of mask with a fresh one for every use)? What about using them right
when putting them on/off and while wearing them (masks are efficient only when
worn correctly, or not?)?

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pcunite
I've been following Dr. Fauci's advice. He is the expert.

[https://youtu.be/LScHAvufgfM](https://youtu.be/LScHAvufgfM)

Thoughts?

~~~
Vastov
You are correct, Fauci is an expert.

It seems that you are being obtuse to prove some kind of point about how masks
are useless and this is a grand conspiracy, especially since you have linked
to a “QAnon” YouTube channel, but I will play along.

In this video, Dr. Fauci discusses the usefulness of an individual wearing a
mask. The conversation is specifically about a mask’s efficacy in preventing
the wearer from becoming exposed to viral particles.

Dr. Fauci expresses concern that individuals will believe they are more
protected than they actually are, and they may be lulled into a false sense of
security, as any mask except a properly fitted N95 respirator will not
actually prevent you from inhaling sufficiently small droplets containing
viral particles.

Dr. Fauci also expresses concern that the general public may not understand
how to appropriately use masks by which he means that it is imperative that
wearers do not touch the outward facing part of the mask and contaminate their
hands and that they don and doff the mask appropriately.

Neither of those concerns have anything to do with the entirely separate
societal benefit of individual mask wearing by preventing you,as a potential
symptomatic/asymptomatic/pre-symptomatic carrier of COVID, from contributing
to the infection of others. At a minimum, masks reduce the volume and the
distance you spread viral-laden droplets by talking, coughing, breathing, etc.

It is also worth noting that your linked interview appears to have been
recorded before the push for mask wearing as a potential guard against
transmission was a part of public discourse. This explains why the second
point is not mentioned.

As an aside, I hope that you can see your way out of this conspiratorial
mindset. I am sure you are, like many on this forum, a very bright person, but
you have to understand that by posting these things and contributing to the
spread of misinformation, you are going to harm people.

