Masks - Review & Charcterization

[RWebb]

Flow regimes characterized

also - silk is good


https://aip.scitation.org/doi/10.1063/5.0029767

[island911]

Wow. Good find.

However, N95 was found to be most effective in limiting the spread of cough droplets. Leung et al.91 performed experimental studies to investigate the efficacy of surgical facemasks to prevent respiratory virus shedding. The surgical facemasks’ efficiency was measured against the coronavirus, influenza virus, and rhinovirus of two broad particle sizes, respiratory droplets (≥5 μm) and aerosols (droplet nuclei with aerodynamic diameter ≤5 μm). The results indicated that surgical facemasks could efficaciously prevent the transmission of human coronaviruses and influenza viruses into the environment in respiratory droplets, but no significant reduction in aerosols.

I bolded the parts that I've been saying for months.

[island911]

more bold on what I've been saying

According to the reported clinical observation study by Samannan et al.,101 the wearing of facemasks neither significantly restricted the gas exchange (oxygen circulation) nor contributed to carbon dioxide buildup, even in persons with severe lung impairment.
Nevertheless, prolonged use of facemasks has some side effects on human respiratory health, such as thermal stress, drowsiness, breathing problems because of restricted fresh airflow, and unusual heart rate.102,103 The discomfort felt with surgical mask use has also been ascribed to neurological reactions or associated psychological phenomena such as anxiety, claustrophobia, or affective responses to the perceived difficulty in breathing.101 In addition, if a facemask is donned for a longer period, the filter gets wet because of facial sweat, and vapor is formed inside the facemasks due to the breathing, resulting in clogging of particulates. In addition, wearers get a false sense of security, encouraging them to spend more time in public places.104 Other potential side effects of facemasks’ wearing include skin irritation, uncomfortable feeling due to the arrival of exhaled air into the eye, comprised quality, and the volume of the speech during the conversations.19,105,106

That last bit I hadn't really thought too far on. That when talking with a surgical mask on you have to almost shout thru the mask.

[island911]

And I have to point out, that while I can follow the math I often wonder why people include it.

A bunch of pedantic approximations to say what a masked guy with a vape pipe can say.

[RWebb]

The math is there b/c it is written physicists who like to figure out how fluid flow works.


The paper directly contradicts a number of memes that island has been posting for some time.

[island911]

Oh webb...

physicists know how fluid flow works. Those eqns are nothing new.

[island911]

And I'll bite, where are these big contradictions?

[Zeke]

That's a very long article. So instead of you scientists bickering, why not decipher and give us the cliff notes and what the skinny is.

[island911]

I thought that I did.

surgical facemasks could efficaciously prevent the transmission of human coronaviruses and influenza viruses into the environment in respiratory droplets, but no significant reduction in aerosols.

[facemask] wearers get a false sense of security, encouraging them to spend more time in public places

Of course there is a lot more specificity about the physics, but the take-away is in that vape mask image.

I have been saying for a very long time that this virus does not escape bodies only as spittle - that much smaller aerosols will also be exhaled.

Yes, the study says a surgery mask stops/slows spittle. Yes some spittle will fall just 3 feet away..

Maybe if I had a Paul Harvey The rest of the story line people would hear about the vapor nature of expelled virus. But, too many are focused on one mental model - spittle transmission. They cling to this as the ONLY thing that needs to be considered. :-/

[ckissick]

The article is very scientific and all, but doesn't the set of graphs in the attached article shed some doubt on the conclusion that masks are effective? Should we rely on equations and theory, or raw data?

https://swprs.org/face-masks-evidence/#jp-carousel-38978

[island911]

Originally Posted by ckissick

The article is very scientific and all, but doesn't the set of graphs in the attached article shed some doubt on the conclusion that masks are effective?..

Yes it does. But it slices and dices the relative fluid (particle) dynamics. Which is fun for some.

Originally Posted by ckissick

. Should we rely on equations and theory, or raw data?

https://swprs.org/face-masks-evidence/#jp-carousel-38978

Exactly.

I will note that people like the solidarity of mask wearing. - oh look, everyone else is miserable behind a mask too. Then some guy walks along with a bare face and resentment and rage fills the masked minion.

Like Cramer, not wanting to wear the Rrrribbon.

[RWebb]

Originally Posted by Zeke

That's a very long article. So instead of you scientists bickering, why not decipher and give us the cliff notes and what the skinny is.

I am the only scientist who has posted here.

as the OP noted silk is interesting

[island911]

Originally Posted by RWebb

I am the only scientist who has posted here.

as the OP noted silk is interesting

LOL

Hey Mr Scientist... Remember when you railed on about how the China virus could not survive without being in some sort of liquid? Yeah, fun times.

[URY914]

island thinks he's an expert in face masks.

[island911]

Originally Posted by URY914

island thinks he's an expert in face masks.

Speaking for what I think eh?

Sounds like Paul Woodbury thinks he's an expert on what island911 thinks.

So Paul, what am I thinking right now? - besides the obvious that you added nothing to this thread but a stupid slight.

indeed.

[URY914]

Did I touch a nerve?

[Bob Kontak]

Originally Posted by URY914

Did I touch a nerve?

You chapped his ass. Like a boss.

[dad911]

For Island:

[ckissick]

Originally Posted by RWebb

I am the only scientist who has posted here.

as the OP noted silk is interesting

Just curious, what sort of scientist are you? I guess I'm the only other scientist here. (Geologist)

[RWebb]

Originally Posted by island911

LOL

Hey Mr Scientist... Remember when you railed on about how the China virus could not survive without being in some sort of liquid? Yeah, fun times.

only a fool would misinterpret what I actually said - that isn't far off tho