Face Shields Ineffective at Trapping Aerosols, Says Japanese Supercomputer (theguardian.com) 112
Plastic face shields are almost totally ineffective at trapping respiratory aerosols, according to modelling in Japan, casting doubt on their effectiveness in preventing the spread of coronavirus. From a report: A simulation using Fugaku, the world's fastest supercomputer, found that almost 100% of airborne droplets of less than 5 micrometres in size escaped through plastic visors of the kind often used by people working in service industries. One micrometre is one millionth of a metre. In addition, about half of larger droplets measuring 50 micrometres found their way into the air, according to Riken, a government-backed research institute in the western city of Kobe.
This week, senior scientists in Britain criticised the government for stressing the importance of hand-washing while placing insufficient emphasis on aerosol transmission and ventilation, factors that Japanese authorities have outlined in public health advice throughout the pandemic. As some countries have attempted to open up their economies, face shields are becoming a common sight in sectors that emphasise contact with the public, such as shops and beauty salons. Makoto Tsubokura, team leader at Riken's centre for computational science, said the simulation combined air flow with the reproduction of tens of thousand of droplets of different sizes, from under 1 micrometre to several hundred micrometres.
This week, senior scientists in Britain criticised the government for stressing the importance of hand-washing while placing insufficient emphasis on aerosol transmission and ventilation, factors that Japanese authorities have outlined in public health advice throughout the pandemic. As some countries have attempted to open up their economies, face shields are becoming a common sight in sectors that emphasise contact with the public, such as shops and beauty salons. Makoto Tsubokura, team leader at Riken's centre for computational science, said the simulation combined air flow with the reproduction of tens of thousand of droplets of different sizes, from under 1 micrometre to several hundred micrometres.
Duh. (Score:5, Informative)
Aerosols move with air. Anything that doesn't restrict air flow can't feasibly protect against them. The only useful things that visors can do are prevent you from touching your face and prevent people from sneezing directly on you (droplet propagation).
Whether that is useful or not is an entirely different question from whether visors prevent the spread of aerosols.
There's still some discussion about whether (Score:3)
That said, I'm not going back to normal until this shit is well and truly under control, and that means my *dollars* aren't going back to normal either. I haven't filled my gas tank in months and haven't eaten out since February. If we want the eco
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Just to point out, that's actually kind of disingenuous. If I had to sit next to someone and was asked to choose between sitting next to a person with a cloth mask or a person with a vented N95 mask, unless the person with the N95 mask was actively coughing, I'd pick the person with the vented N95 mask any day of the week and twice on Sunday. Why? Because assuming all else is equal, that person is far less likely to have gotten sick in the first place, which more than makes up for the loss of the tiny b
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"I'd pick the person with the vented N95 mask any day of the week and twice on Sunday. Why? Because assuming all else is equal, that person is far less likely to have gotten sick in the first place, "
So you also ASSume that person does this 24/7 and can't be infected by their kids or cats at home?
Can I subscribe to your newsletter?
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There's been no evidence of transmission from pets. And if you're wearing an N95 mask, I'm betting you're keeping your kids safety as a high priority as well. There are no absolutes, only odds, and that's his point.
Re: There's still some discussion about whether (Score:2)
Say it, don't spray it (Score:2)
Most of us have heard the expression "say it, don't spray it".
Those droplets are much, much larger than 5nm.
> it's not replacement for a proper multi layer cloth mask or an N95 if you're in healthcare.
Agreed. If you're in healthcare, especially dealing with probe who have serious infectious diseases, you want really good protection. For everyone else, reducing the spread rate of covid by just 50%, something that is only halfway effective, can mean the number of new infections DROPS by 30% each month, u
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What crap twaddle. A bureaucrat in love with bullshit number. One person in an internation airport can spread it to say 100,000 people in 48 hours. You numbers are entirely delusional and take zero account of chaotic spread. Look like they mean something but in reality, it is all down to the interactions, completely chaotic, because those individual interactions can spread it to none or spread it to 100,000 entirely down to individual interactions.
The only big difference in spread has been the level of TB
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> but of course not at $3,000 a dose, on no, fuck all profit in that.
Just FYI, the vaccines are $10-20dose.
That's the contracted prices for the first 100 million doses or so. Of course it may come down after that.
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The problem is defining "halfway effective".
If by that you mean, cloth masks do not stop the spread of the virus (which they don't) and only reduce the distance doplets travel, then I think its not effective at all. A droplet sprayed out doesn't magically disintegrate like a computer game bullet after a certain time.
so masks do little to nothing to stop the spread. They may feel like they do, but they don't. This was proven in 1918. Studies showed cities that mandated masks had just as many virus deaths as
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> The problem is defining "halfway effective".
Halfway effective meaning it reduces by half the number of people who catch it from each currently infected person, on average. Suppose in the control group, each infected person passes it to 1.5 other people, so each round 50% more people get it. A "halfway effective" protection would be one for which each infected person passes it to 0.75 people. Which would mean that the nunber of people who get infected drops by 25% each round.
I'm fortunate that before
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That first video was wierd. But it had this as "next up". I've stopped it at the right point for you:
https://youtu.be/0Tp0zB904Mc?t... [youtu.be]
as he says, if you don't wear one fitted just right, it's as ineffective as not wearing one - like the plastic visors.
And that's the point, as the stockton v boston analysis showed, masks do not work. They do if you're a medical professional, but not if you're wearing a home-made one that's a bit grubby, too tight, too loose, or you shift it about to stick your fingers up you
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> They go on and on about how they work, why you should wear one, and use only "no mask" against "perfect mask" as examples afterwards. That's not what happens in the real world, their apolgism is useless.
That's what YOU are doing. YOU are saying "not perfect" == "useless". Which SO the opposite of the truth here - the total in infections reduction is EXPONENTIAL to the reduction in droplets!
The very first words at the point where you cued the video are "mask you sewed at home they all have a lot of d
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I'll watch the results of those experiments, and the videos of stuff coming out people's mouths even with a mask on. Note - these are well placed, clean masks, not the crap people are wearing.
These videos are apologists for them, did you think, wacthing the petri dish experiment "so what, all the virus particles may not travel to infect someone, but the ones that do come out closely, will hang around in the air and infect anyone who walks into them?"
Did you not wonder that because you're blindly nodding alo
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This has actually been pretty darn well tested over the last 120 years or so. Which is why masks have been standard equipment in every medical practice for the last hundred years. Only in the US in 2020 did somebody try to say its NOT good idea to stop the saliva spray of an infected person from spraying directly unto your mouth and nose. The rest of the world sees the US as crazy for this kind of crap.
You can start for example with this landmark 1905 study in JAMA.
https://books.google.com/books... [google.com]
Where the anti-maskers are right (Score:2)
I should acknowledge where the anti-maskers are right and where I think some of this is coming from. In certain cities and counties, local government instituted stiff fines and even jail time for not wearing a mask.
That was a fight in Texas, for example where certain counties even put people in jail and Texas governor Greg Abbot said no, you can't do that, you can't throw someone in jail for forgetting their mask. OF COURSE that kind of thing led to a "fuck you and your masks" reaction.
I absolutely underst
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This was proven in 1918.
Well, we certainly would rather go with 102 year old research
than 2020 research!
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The only 2020 research says that masks are ineffective - you're replying to a story on /. about it.
And viruses and cotton masks haven't changed since they were invented.
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https://health.clevelandclinic... [clevelandclinic.org]
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> No numbnuts - in case you're still following the WHO
The WHO has stated the "novel corona virus" is not human transmissible, so I don't see why you're worried.
"Preliminary investigations conducted by the Chinese authorities have found no clear evidence of human-to-human transmission of the novel #coronavirus (2019-nCoV) identified in #Wuhan, #China"
https://twitter.com/WHO/status... [twitter.com]
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That was in January. Pretty sure that the clear evidence of human to human transmission has now been found.
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WHO says: "...found no clear evidence of human-to-human transmission"
You interpret as: "is not human transmissible"
How do you manage to make that jump in logic? They're not even close to the same meaning.
If they haven't found something happening, then that does not imply it does not happen.
I'm quite sure that both the Chinese authorities and the WHO chose their words very carefully so as to be as clear and precise as possible.
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Yeah, exactly. How do you only get rated as '0' but the parent is '3'....moderators suck.
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The aerosol versus non-aerosol question is like asking whether walking across the street outside will give you skin cancer. If you look at enough people, you'll find someone who got skin cancer that way. The question is the probability of that occurring.
Almost every non-blood-borne virus — and certainly almost every respiratory virus — is, to one extent or another, airborne. With some viruses, the probability of aerosol transmission is incredibly high because the number of virus particles re
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This NIH study would seem to refute your position.
https://pubmed.ncbi.nlm.nih.go... [nih.gov]
"Face shields can substantially reduce the short-term exposure of health care workers to large infectious aerosol particles, but smaller particles can remain airborne longer and flow around the face shield more easily to be inhaled. Thus, face shields provide a useful adjunct to respiratory protection for workers caring for patients with respiratory infections."
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Actually, they're agreeing with me. "Large infectious aerosol particles" is a fancy way to say "droplets", at least to within the margin of error.
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Sigh, another internet expert who can't accept science.
Cleveland Clinic also had this to say:
“Because they extend down from the forehead, shields protect the eyes as well as the nose and mouth,” says pediatric infectious disease specialist Frank Esper, MD. The coverage that face shields offer is ideal since the new coronavirus can enter the body through those points.
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Cleveland Clinic also had this to say: “Because they extend down from the forehead, shields protect the eyes as well as the nose and mouth,” says pediatric infectious disease specialist Frank Esper, MD. The coverage that face shields offer is ideal since the new coronavirus can enter the body through those points.
Okay, I think I understand the problem. You're not talking about what this article is talking about.
There are two very different things that qualify as face shields. One is the sort of bunny-suit face shield that medical researchers wear, and one is the cheap crap that you buy on Amazon. That doctor was likely talking about bunny-suite-style medical face shields, which seal against your head/chest and have built-in respirators or dedicated air supplies to provide the air that you breathe. They protect y
In hindsight, seems pretty obvious (Score:4, Interesting)
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I don't know how much practical meaning this study has. Most of the retail employees I see wearing shields tilt them up to about the bridge of their nose anyway. It's pretty obvious they're an excuse to not wear a layered mask. The sole function of face shields for me is as a litmus test for if a store's management takes Covid seriously or not.
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Either there is a major education failure or people don't care. A shopper, in a local store, was actually wearing a white hockey mask. Like that would stop droplets...
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> A shopper, in a local store, was actually wearing a white hockey mask. Like that would stop droplets...
The mask rule is just to appease morons. Are you not appeased?
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A shopper, in a local store, was actually wearing a white hockey mask
Was his name Jason?
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Some people are just taking their own peculiar paths to refusing to wear a mask -- such as wearing one that doesn't work, and everyone looking can tell it doesn't work. That's, like, double-owning the libs or something.
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I use mosquito netting for my "mask". Others are buying the "High Flow Exercise" masks that have visible holes in them. It's all theater so who cares.
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Exactly....why did they bother with a supercomputer for this simple logic.
The best it can do with an aerosol is direct air flow away from your face, and that is better than not doing so.
It's no replacement for something better, but in addition it is better. In addition to a mouth mask (adds protection for the eyes); in addition to washing hands often; in addition to distancing; more people doing likewise.
Essentially, don't be stupid people.
Self absorbed (Score:2)
It's not about being Self absorbed (Score:4, Insightful)
Nobody's going to feel like the Administration's COVID response has been a success when we're all still wearing masks.
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I'd argue that there's justification for people who work with the general public to have their mouth visible as it helps aid in communication [ucl.ac.uk], especially with those who suffer from hearing loss and/or utilize hearing aids.
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So almost nobody. Also, if the situation actually requires not wearing a mask, do it from a good distance away or use a plexi-glass shield.
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> So almost nobody.
lol. More people suffer from hearing loss than people who suffer from COVID-19...
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Flip it around. The topic at hand was people who must communicate clearly with the public. That would be almost nobody. Even less if you only count the ones who in spite of their need to communicate clearly with the public, have neglected to either learn ASL or hire an interpreter.
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Flip it around. The topic at hand was people who must communicate clearly with the public. That would be almost nobody. Even less if you only count the ones who in spite of their need to communicate clearly with the public, have neglected to either learn ASL or hire an interpreter.
So the grocery store clerk who has to explain to a customer who is hard of hearing where the baking soda is, doesn't need to communicate? That being said, there's solutions [rafinova.com] that are available [etsy.com].
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How hard if it to speak up and say "Aisle 5" while gesturing towards the aisles then holding up 5 fingers?
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13% of the US population has hearing loss. If that's almost nobody, what's the 2% of the US population had COVID-19? Definitely nobody. And the fraction of that who died from it? Meh.
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READ CAREFULLY!
I was referring to the number of people who have a pressing need to communicate clearly with the public as a percentage of the people who are out and about.
I was NOT talking about the number of people who have impaired hearing.
The whole thread was started as a red herring by yet another person looking for an excuse why nobody can wear a mask ever.
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Aside from disabilities, health concerns, religious exemptions, political bias, fake news, and a mask mandate being an illegitimate power grab, simply not wanting to wear a mask should be reason enough in a free country.
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Have you ever heard the expression "Your right to swing your fist ends at my nose."? That applies here. You do NOT have a right to spread disease to others and contribute to prolonging a pandemic. Just like you don't have the freedom to dump your garbage can in your neighbor's pool (I'm HOPING you don't believe otherwise on that one) or poop in a public fountain (REALLY hoping you don't believe otherwise!).
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It violates the NAP to intentionally make someone else ill. But you can fuck right off with forcing draconian measures on healthy people.
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The problem is, you don't necessarily know you have and are spreading covid until days later.
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That's part of the human condition. You can spend your life living in fear if you choose, but don't demand the rest of the world do the same. Especially for something that has proven no more deadly than the flu.
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I guess your worst nightmare is "No Shirt, No Shoes, No Service".
Mask mandates have been repeatedly shown to reduce illness and deaths from covid.
Next time you need surgery, feel free to suggest the surgeon forego the mask if you want, but for the duration when going out and about, do try not to be a flaming asshole making people sick.
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Private businesses should be free to make their own rules. But government has stepped in and changed that. Bake the cake! I still support their decisions, and I am not spending my money in places that enforce masks.
Mask mandates have been shown to make a 3%-4% reduction in infections. That means they did 96%-97% fuck all.
I'm not wearing a mask. I'm not making others sick. I'm not sick. You can wear a mask if you want. You can stay home if you want. But you don't get to control everyone else just be
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And yet where there are mask mandates, infection rates are going down and the economy is starting to thaw. Where there are not, the infection rate is going up and the economy is freezing up.
Enjoy your high death rate and fried economy, but kindly stay away from me.
Perhaps you should try protesting the restriction of your freedumbs by running naked through a city park.
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Infections are down everywhere. The death rate was never high except for those who were already beyond their life expectancy. The fried economy is from locking healthy people down for 6+ months after the "15 days" most people agreed to.
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Not self-absorbed. I teach English as a Foreign language. That means a lot of modelling pronunciation & sometimes demonstrating how sounds (phonemes) are physically articulated. I doesn't mean we can't teach anymore but it does put some awkward limitations on how well we can teach & that we can't address certain pronunciation issues. Also, my & my students' voices are quite muffled by masks which makes it difficult to hear some fricative phonemes which are essential for understanding.
In practica
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Pretty self-absorbed [psychologytoday.com], actually.
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> How self absorbed do you have to be to not want your face to be obscured by a mask?
They should make a law that you have to wear a garlic bulb around your neck to ward away vampires. I'm sick of all these vamps!
It was polite about it though (Score:3)
In addition, it said, "If you're not wearing a mask and must sneeze or cough, please do so in your sleeve [youtu.be]. Also, please stop sneezing on me."
Moderately impactful study (Score:1)
This is not surprising. Visors don't even offer full protection against droplet spread. We already know that only upscale filters offer sufficient protection when disregarding other factors.
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Yeah, Captain Obvious was promoted to Major Obvious, and well on his way to General Obvious on this.
That makes intuitive sense (Score:2)
Micron, not micrometer! (Score:1)
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"Micron" is indeed the common name and valid, but "micrometre" is still entirely correct.
And it's only spelled the same as "micrometer" in the USA, the only major country in the world that doesn't primarily use the metric system in the first place, so I'm honestly not sure that it matters very much.
Not mention that words that are spelled the same can have different meanings simply depending on how they pronounced (or sometimes even that is the same), and when looking at how the word is being used, you
A face shield is for eye protection (Score:2)
and you wear it in addition to your mask.
Or you could wear goggles or protective glasses.
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still (Score:2)
it is still better than nothing.
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>"It is still better than nothing."
For aeresol protection? No, not really. It does absolutely nothing but:
1) Look like something (AKA- virtue signaling)
2) Cost money for nothing
3) Interfere vision and speaking, lower comfort
3) Give a VERY false sense of security
Aeresol protection requires a properly-fitted and properly-rated respirator, nothing less (and even that doesn't protect skin or eyes). Ask ANY healthcare worker with any PPE training.
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Ask ANY healthcare worker with any PPE
Who all wear shields when close to people who are coughing or sneezing. And healthcare workers can't do their job and maintain safe distance.
Breathing isn't the only way to spread COVID:
having someone sneeze close by could cause droplets
to land in your eyes. That's just as bad.
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>"Breathing isn't the only way to spread COVID: having someone sneeze close by could cause droplets"
The article and my posting are about aerosols and face masks. Not COVID-19 and droplets.
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>"That's a bit like saying body armor is useless because it doesn't help if you get shot in the back. It protects you in the direction most people care about, directly in front."
An aerosol hangs in the air and spreads everywhere, very quickly. Once contaminated, if you are breathing the air, you are infected, shield or no. Bullets do not act that way at all. I don't think you made a reasonable analogy.
"Not perfect" or ineffective? (Score:2)
What is actually interesting is: How much does the number of viruses reduced that cover 1 meter, 2 meters, 3 meters, or 10 meters to another person?
Zero percent reduction = ineffective. Anything above that but below 100% is effective, but not perfect. I'm told that face masks with valves, like those that the UK Chanc
Was this even in question? (Score:5, Informative)
>"A simulation using Fugaku, the world's fastest supercomputer, found that almost 100% of airborne droplets of less than 5 micrometres in size escaped through plastic visors of the kind often used by people working in service industries."
1) Duh. An aerosol is not the same category as droplet.
2) They are examining the wrong direction- face SHIELDS are worn by healthcare workers to protect against droplet spray from patients. I have NEVER seen them used in the OTHER direction (to protect patients from a health worker).
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> found that almost 100% of airborne
Why do people keep not reading 'almost'?
It literally means it is better than not.
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OK, but why are they wearing them? ...and does it matter why? The fact is, they do provide some protection so they're better than nothing. Even this study says that (use of the word 'almost' is literally saying as much).
Never even considered (Score:3)
Recently had people mention face shields are ineffective and it made me wonder what BS they've been reading online.
I never even considered people would think of using shields as substitutes for masks. Apparently it takes fancy fluid simulations to confirm this is just as dumb as it sounds.
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I find that difficult to believe. I suspect she was just objecting to having to put the effort into re-forming the boxes, and preferred to waste the fuel rather than put in the effort.
> That's when I understood why she kept saying she could only fit a few empty boxes into her car at a time
This made me laugh, though. You should have told her that you could put in some packing material (peanuts?) and then she can get more in her car.
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I never even considered people would think of using shields as substitutes for masks. Apparently it takes fancy fluid simulations to confirm this is just as dumb as it sounds.
People use face shields *in addition to* masks, just like what health care professionals do when working with covid patients.
It protects the wearer, especially the eyes, from *droplets*. If anyone thinks it is useless, just consider if you want to be sneezed at directly with or without a face shield, even if you were already wearing a surgical face mask.
Face shields... Gimme a break (Score:2)
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If they are 3D-printed they are not bullshit, they are usually PLA or PETG.
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Face shields are used specifically to prevent droplet spray from sick people hitting healthy people in the face. They are completely different in purpose to a mask. A mask won't protect you if someone sneezed in your face.
Masks are to protect others from you
Face shields are to protect your face from others.
For proper protection you should wear both which is precisely what medical professionals do. And as for the "making money" angle. Don't be frigging stupid. The large majority of them are being managed thr
Face shields were never about trapping aerosols (Score:1)
It's all about appearing to trap aerosols to psycho people. The same people who freak out if you are standing at 5'9" instead of 6'. A face shield will appeal to these people, why? because its something over your face.
It's all about appearing to trap aerosols to dumb people.
The same people who wear masks in their cars or outside when they are a mile away from people.
Masks are about social appeasement. I think they work personally, I wear one, but the social aspect has gone way to far.
Japanese Suercomputers. Or common sense. (Score:2)
Did anybody think that a face-shield alone would do anything to prevent aerosols transmitting virii? I didn't. They're a quasi stop-gap for goggles, but I don't know anybody who seriously thought that a face-shield would replace a mask.
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Also what has that super computer been used for instead of Covid topics for the past six months? Figuring out Pi?
To paraphrase "The Wedding Singer" :
Things that could have been brought to my attention in MARCH !
Shields protect the wearer. Still need a mask! (Score:2)
Shields protect the wearer, such as protecting a health professional from a COVID-19 patient sneezing toward them.
The shield does not in any way replace or reduce the need for a mask.
Masks protect both the wearer (to a limited extent) and others (to a far greater extent).
In light of new CDC statistics... (Score:1)
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allow the rest to go back to normalcy and get regular healthcare and socialization.
Without masks. Even though the data you are basing this on says
So, even though it's easily spread by people who don't even know they are infected. You want people to just go back to normal without masks. All because it's only 50+ year old's, who have a 5% chance of dying. When they stumble upon
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Uh, it's those above 70 years old that have a 5% chance of dying. Those from 50 to 70 have a 0.5% chance. And there are many who ARE dying from lack of healthcare, joblessness, depression, and more. At what point do we realize the "cure" (it was supposed to be "flatten the curve" so we don't overwhelm the hospitals) is worse than the disease?
I know my local ACE hardware - family owned for 55 years - is now permanently closed, because they've been forced to be locked down. Meanwhile, the Lowe's and Home
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deaths with CoVID (not necessarily FROM CoVID)
Oh you're one of them.
So you want to...
allow the rest to go back to normalcy and get regular healthcare and socialization.
Without masks. Even though the data you are basing this on says
So, even though it's easily spread by people who don't even know they are infected. You want people to just go back to normal without masks. All because it's only 70+ year old's, who have a 5% chance of dying. When they stumble upon one of your, "going back to normal infected young people". Active known cases in America are around 2.5 million. Plenty more unknown cases. And with an R0 of 2.5 that will grow quite quickly with your "let her rip" strategy.
Do you not understand, or do you just not care?
How many 70+ year old's are there in that 1 million?
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Eighty percent of the population suffers from gingivitis. Eighty percent of people who die, died with gingivitis.
So you need to explain why they didn't all die last year or the year before that etc.
The fail here is in your position.
My failure was in taking you the slightest bit seriously.
I notice you completely failed to answer the question. Instead trying to steer the discussion off topic.
I'll answer it for you, and show why you tried to hide it away.
There are about 65,000 people in Ventura 70 years or older.
Your "don't wear a mask", "go back to normal", "let
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Huh?
NY: 33,188 deaths (1706 deaths per million).
FL: 13,795 deaths (642 per million).
NY has nearly triple the number of deaths. FL did what we were supposed to use the masks to do - flatten the curve. And flatten, they did. NY is the death-capital of the world..
Source [worldometers.info].
Shields are not about trapping aerosols (Score:2)
That's what a mask is for. Face shields protect the face of someone from spray by someone else infected. A mask won't prevent you getting COVID-19 if someone sneezes in your face.
There's a reason medical professionals wear both.
NIH Study on Face Shields (Score:2)
https://pubmed.ncbi.nlm.nih.go... [nih.gov]
Face shields can substantially reduce the short-term exposure of health care workers to large infectious aerosol particles, but smaller particles can remain airborne longer and flow around the face shield more easily to be inhaled. Thus, face shields provide a useful adjunct to respiratory protection for workers caring for patients with respiratory infections.