The origin story of the N95 mask | Hacker News Reader

The origin story of the N95 mask

fastcompany.com

212 pointswallflower153 comments

Other than invented face mask, Dr. Lien-teh Wu was the first medical student of Chinese descent to study at the University of Cambridge and graduated top class. Later Dr. Wu had also studied at Pasteur Institute, the world's renowned institute on infectious disease. After successfully led the containment effort for Manchurian Pneumonic Plague of 1910–1911, he co-founded Chinese Medical Association. He was also widely considered the pioneer of public health and the founding father of modern medicine in China.

https://en.wikipedia.org/wiki/Wu_Lien-teh

Didn't the plague doctors with the bird masks predate that?

> Wu explains to the French doctor his theory that plague is pneumonic and airborne (...) And the French guy humiliates him . . . and in very racist terms says, ‘What can we expect from a Chinaman?’ And to prove this point, [the French doctor] goes and attends the sick in a plague hospital without wearing Wu’s mask, and he dies in two days with plague.

Maybe we're like this French doctor, and that this is still the reason why we don't wear masks in the west? A widespread practice in several East Asian countries - but what do they know?

The reason we don't is because we weren't dramatically affected by SARS. SARS in the early '00s was primarily a problem in Asia.

Japanese people also have an etiquette of wearing a mask when ill to avoid spreading disease.

Both of these habits are widespread in Asia because of this.

Also in many Asian cities masks are worn due to air pollution.

and even in clean areas some people still wear them because they help keep your face warm when it's cold.

or it's just common courtesy trying to not infect others with your illness like in Japan

Or, maybe because people go from clean to dirty areas.

I picked up this habit because of widespread pollution in New Delhi

Mask culture in Southeast Asia (to stop disease transmission) predated SARS for decades.

If we have a high percentage of asymptomatic carriers, and masks reduce transmission substantially, it would be great to see a cultural change in Western countries to make them commonplace whenever you are in public.

If the fashion industry gets on board to make them look nice and production ramps up to make them widespread and affordable, we may actually see mass societal change around this.

One major weakness of the current N95 masks is that sometimes it doesn't seal very well to the contours of people's faces. When this happens, it doesn't work as well because particles can still travel into the airway via open space gaps.

I personally have not seen this implemented, but one possible solution I believe may work is to apply a thin layer of sticky hydrogen tape right along the edges of the mask so it would act like an adhesive that helps seal the open space gaps as it can fit with the unique shape and contour of each person's face.

Medical hydrogen tape is the same material that we often see being used in those sticky pads that they put on a person's body during an electrocardiogram (EKG) test. It's also the same adhesive that used by those electro pads in TENS pain-relief machines. This sticky adhesive material is safe for human skins and can last multiple uses.

It would be great if someone could add a feature in which you can insert a removable HEPA filter so it can be swapped in and out when needed.

For public health use (as opposed to medical use), the difference between an N95 mask and a surgical mask is pretty small. They both make a huge difference.

It's true: air can come around if the seal isn't perfect. However, you've eliminated most of the virus. At that point, other modes of spread become dominant.

In a medical setting, where you're guarding against all modes of spread with a full body suit, googles, etc., and where you're dealing with large numbers of exposures, it's a completely different story.

Ballpark numbers for masks+frequent handwashing suggest that they'd bring R0 close to 1, assuming a whole bunch of unvalidated assumptions (e.g. they have the same impact on coronavirus as on the flu). At that point, we should be able to get things under control with social distancing and similar measures.

When I was doing a lot of sanding, I had one of these masks, and taped it around the edges to my face. The mask would have been utterly useless if I hadn't done so, as all the dust would have just come around the edges. I just used painters' masking tape. It worked.

Most people probably won't put it on correctly, per this claim:

"I remember my respirator training, the last time I worked in a hospital. They gave the standard two minute explanation, made you put the respirator on, and then made you go underneath a hood where they squirted some aerosolized sugar solution. If you could smell the sugar, your respirator was leaky and you failed. I tried so hard and I failed so many times. It was embarrassing and I hated it.

"I’m naturally clumsy and always bad at that kind of thing. Some people were able to listen to the two minute explanation and then pass right away. Those kinds of people could probably also listen to a two minute YouTube explanation and be fine. So I don’t want to claim it’s impossible or requires lots of specialized background knowledge. It’s just a slightly difficult physical skill you have to get right...You are unlikely to be able to figure out how to use an N95 respirator correctly. I’m not saying it’s impossible, if you try really hard, but assume you’re going to fail unless you have some reason to think otherwise."

https://slatestarcodex.com/2020/03/23/face-masks-much-more-t...

The problem of facial sealing is well-solved in the industrial space. People who routinely need respiratory protection for stuff other than particulates use a half-face (or full face) respirator [0] that has a body made of some flexible material that seals to the face far better than an N95 mask.

You can get particulate cartridges in the N or P-flavored type, which I use for sanding. It's also usually possible to get a particulate pre-filter on top of e.g. an organic vapor cartridge.

Respirators also come in sizes and need to be fit-tested. The quick and dirty method is to take off the cartridges, seal the holes they mount to and breathe in. If you feel your ears popping, it fits-ish (EDITED TO ADD: I am not an industrial hygienist, and I'm principally worried about wood dust not organic vapors or acid vapors or anything really bad. Don't take industrial hygiene advice from some random on the internet!). A proper fit test involves somebody puffing something around the mask while you breathe, talk, and possibly a few other things.

As it happens, for a proper seal, you also need to be clean-shaven. As I'm principally protecting myself from wood dust, I don't bother. If I'm using something noxious (like paint stripper), I'll shave and put on the correct cartridges.

Whether or not this is a solution to the current medical problem is beyond my expertise. There may be an advantage to regularly disposing of your N95 mask to prevent accidental contamination or something.

[0] https://www.3m.com/3M/en_US/company-us/all-3m-products/~/All...

Im a fan of the pink p95 & p100 disposables with nuisance level organic filtering. I want to say 2097? I used them for small painting, welding, and brazing jobs. Work a treat with organic solvents & weak acid vapors and IIRC they werent much more than the regular N & P series. The carts were nice with theprefilters but then I just have more things to keep in stock.

2097/2297 are nice, 7093 is a bit better as the plastic casing provides a bit of protection against the rain.

60926 is anecdotally proven to work in environments highly polluted with oily crystals for at least a few hours.

The difficulty in achieving a proper face seal is apparently why the US Army doesn't allow most soldiers to have beards.

"Actually, when I went to Israel I went and … talked about beards and challenges and issues, and had a lot of long discussions about it, and bottom line is, it poses a threat to our soldiers on the battlefield. There’s … data to prove it’s very difficult for the seal on a protective mask."

https://taskandpurpose.com/news/army-daniel-dailey-tattoos-b...

it's already being done. In today's (very disturbing) article about New York health workers:

A nurse on her unit has already contracted the virus and one doctor is so scared he affixes an N95 mask to his face with tape at the beginning of each shift.

https://www.nytimes.com/2020/03/30/nyregion/ny-coronavirus-d...

You know, while I like stories like these, I find them equally frustrating because there doesn't seem to be any sources. Just Google the ignorant French doctor's name, for example.

It reminds me of my college psychology class. Our teacher would teach us from a book, then tell us the book was wrong and India had such discoveries prior. Cool to know, but now who knows the truth anymore.

I got sent down a rabbithole of searching by this article too, apparently the doctor wrote an autobiography (in English!) in 1959 that was republished as recently as 2014, but apparently the only way to get ahold of it here is to have it shipped from Malaysia. Or some college libraries, which are unfortunately closed right now due to COVID.

I think we forget that the vast majority (i.e, pre-2005-ish) of human knowledge still exists in the old physical world of print and libraries. Unless you're exceedingly lucky (or it was recently reprinted), its basically impossible to get your hands on a digital version of an old book. Your best hope is that Google Books (which seems mostly abandoned) scanned it and will let you read a few pages.

>Unless you're exceedingly lucky (or it was recently reprinted), its basically impossible to get your hands on a digital version of an old book.

I read a lot of old books - early 20th C, 19th, 18th, 17th C, and medieval and ancient. Archive.org has most of what I search for - nice scans, in multiple formats, free. Also you can often borrow mid-late 20th C stuff online from there for a few weeks if not they're not downloadable outright. Libgen has a lot of stuff from early-mid 20th C and before. If those fail, I order it online, usually a few dollars. We're so spoilt!

Just take solace in the fact that you learned something and you know how to apply what you learn. There are so many things where there is no right answer and one can never be found. Your teacher probably helped you remember the concept better by making a story out of it.

This is such a dumb article.

It focuses on just the one piece of PPE that has gotten an undeserved amount of attention in the coronavirus crisis, when it's not the only tool in the arsenal of healthcare workers (compared with normal surgical masks, face shields, papr devices, etc).

And it is not necessarily the best tool for the general populace. (hypothetically (ballpark numbers from some stuff i remember reading) If a normal surgical mask can be replaced twice as often and is easier to breath through while only sacrificing 30% of protection, etc, what is recommended for the general public? Even the N95 only protects against... 95% of particulates of the specified size, why not wear a P100 filter on a gas mask?).

From a macro and epidemiological standpoint, what is the optimal guidance on the level of PPE for the general public to wear for the greatest net effect? Is what I consider the most interesting and relevant question.

There is also an unchecked assumption in this article that the N95 is "most important design object of our time".

It also fails to explain that N95 is a standard of protection rather than a certain object, it fails to explain the meaning of the standard.

(Which is) N = Not oil resistant 95 = Removes 95% of all particles that are at least 0.3 microns in diameter

It merges the development paths of protective masks against particulates, which is the true purpose of N95 masks, and protective equipment for healthcare. To me, I think N95 happened to be a standard similar enough to the requirements of healthcare, so they simply adopted it. Rather than the false narrative the article paints of the N95 mask being developed FOR medicine.

I would have been interested to read about the additional requirements a FDA defined "surgical N95" must meet (additional fluid resistance), or how the N95 plays into the entire suite of relevant protective equipment in this crisis (When doctors use a normal surgical mask, N95, PAPR, face shield, or goggles).

edit: clickbait article that doesn't give any information beyond what 5 minutes googling would use.

edit2: would have been interesting to read about how people are making face masks and other protective equipment or experiments in sanitizing and reusing one time use face masks.

The mask denialism in the comments is incredible to see.

Let's all agree (without polemics): masks can be helpful, so we should encourage everyone to wear them, unless there is a shortage, in which case priority should be given to healthcare workers/elderlies/front-line staff/etc.

It's fucking stupid. It's like seeing condom denial because some priest says only abstinence works.

And even then people should make their own mask and wear that.

From what I understand the WHO guidance around masks has to do with the shortages on one hand and human behavior on the other hand. People who wear masks behave in a higher risk way, and because the safety benefit from the mask by itself is quite low (without medical training you are likely to use it wrong), statistically it is better to recommend people to not wear masks so they will behave more safely.

It’s a bit like gun ownership: intuitively it makes you safer, but statistically it makes you less safe because of behavioral and opportunity changes.

According to the Corona expert in South Korea, masks help a great deal. His assumption on why the WHO only recommends masks in Asia and not anywhere else is due to the limited amount of supply anywhere but in Asia. In Asia people like already own masks. Anywhere else people would first need to stock up. Leading to shortages. As such, it's better not to recommend them so medical professionals are prioritized.

It's also interesting that in in Europe/US they focus on a person not getting a disease. In Asia they often wear a masks if the person isn't feeling well. Meaning, the mask is to prevent the person who is wearing it from infecting others. This bit is often glossed over.

The video is available at https://youtu.be/gAk7aX5hksU. I don't know exactly where they discussed the masks. The entire video is great, so suggest to watch the whole thing.

Note: It also talks about spreading by touching your nose and then someone or some surface.

>In Asia people like already own masks.

A mask is a biohazard and should be one-use or sterilised and removed with gloves. If you do that then yes a mask is a help. If not you are playing Russian roulette with a Corona bomb on your face. It is amazing how much energy users on HN use on talking and discussing mask use and still don't understand why a mask used wrongly is worse than no mask. Walking around town collecting germs and bringing them home with you is the mindset you need to be in if masks should be a good idea and safe.

Who says we don't understand?

I get that not everyone has been through both SARS and the wanton deployment of tear gas, but it's just common sense for us to dump everything in the wash and have a thorough shower as soon as we get home.

We waste energy on you deniers because we don't want you to become a walking biohazard yourself and infect everyone else.

Part of the supply issue is that China effectively nationalized 3M (etc.) mask production there to prevent export to other countries. Now, they are using the surplus to effectively use mask donation as political donations.

Smart move on their part. Guess this risk was not considered when all the outsourcing was going on.

I think your intuition on safety with gun ownership is culturally specific and maybe not the best example...

I think anything Wuhan Health Organization says should be taken with big grain of salt anymore, they are either extremely incompetent or paid by Chinese gov, none of them serves them well

https://thehill.com/opinion/international/487851-china-and-t...

Same with bike helmets, kids drive riskier and the statistics proofs it.

Like motorcycle helmets wrong use is worse than no use.

The most offensive idea I'm seeing here is that Americans are somehow too stupid to be trusted with masks because they can't put them on properly or will use them as an excuse to ignore social distancing protocols.

I sincerely hope we don't dismiss the success of South Korea simply because of this kind of fatalistic presumption of ineptitude. If South Koreans can do it, Americans ought to be up to the challenge as well, no?

Of course, people clearly will need to be open to listening carefully to their government and to closely adhering to all aspects of transmission-limiting protocols, and be instructed in proper mask fitting. I could certainly imagine seeing a breakdown of that in America, of course, since we'd need people to trust in their government, and for their government to be competent and properly funded. Which are things we frankly aren't good at, apparently for deep-seated cultural reasons.

Can the "mask shaming" be worked around by wearing a bandanna or scarf over the top to hide it, or does that reduce its effectiveness?

In my part of the US (midwest), you would be less likely to be shamed for wearing a mask, even before all this, than a bandanna.

Subsequently, that's the first time I've ever typed bandanna, and I just found out I've been spelling it wrong my entire life in writing. I thought it had one 'n' at the end. Weird.

> The most offensive idea I'm seeing here is that Americans are somehow too stupid to be trusted with masks because they can't put them on properly...

And yet when I watch the news on TV, I see multiple cases of people wandering around outside with a mask over their mouth but not their nose. Perhaps the news people should be pointing that out, and doing a "here's how to use a mask properly" section.

> Perhaps the news people should be pointing that out, and doing a "here's how to use a mask properly" section.

No doubt. We definitely have got a long way to go toward educating the public if mask-wearing is ever going to be a part of slowing down this pandemic.

Is it possible that the business model of 24-hour news is to misinform people by highlighting exceptional cases and portraying them as normal in order to drive views? No, it must be that the public are all dumb-dumbs.

Advocating against the use of other protective measures - condoms, helmets, safety belts - because they're not 100% wouldn't be given the time of day, and it's high time people stopped tolerating or even assuming good-faith from people repeating the same anti-vaxxer level crap they've read someone else regurgitate in another threads.

Actual lives are being put at risk by this anti-mask idiocy; dangerous advice shouldn't be allowed to spread unhindered any more than Covid itself.

Well, you sure told the US Surgeon General [1] and the CDC [2] - good job.

[1] https://twitter.com/Surgeon_General/status/12337257852839321... [2] https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-si...

> masks can be helpful, so we should encourage everyone to wear them

Whether it does or doesn't make sense to use masks, this is not a logical argument. "Masks can be helpful" is almost certainly true, but it doesn't imply that using them is necessarily worth the cost (in terms of material, production capacity required, convenience, etc.).

"X can be helpful so we should do it", without any regard whatsoever to cost (especially opportunity cost), does seem to be the predominant thought process at the moment.

I am a strong believer in the universal mask protocol for controlling COVID-19. I've created https://www.maskssavelives.org/ to help spread the message.

Thank you for this. I wish it was as obvious to others as it is to pretty much anyone who has spent time in East Asia. Masks and the culture of being polite about not spreading disease would be a game changer in the US.

100% agree. Thanks for creating the website. I'll spread the website link in my circle.

This is brilliant.

I’m interested to see if the numbers from Japan that are prevalent on your site hold up. They are doing even less testing than America...

https://www.vox.com/covid-19-coronavirus-explainers/2020/3/2...

It's OK that your 'belief' contradicts official WHO guidance but that 'MASKS-NO MASKS' graph went a bit too far as a misstatement (i.e. "presenting facts in an alternative way").

Let me paste the official advice here for educating readers: https://www.who.int/emergencies/diseases/novel-coronavirus-2...

> If you are healthy, you only need to wear a mask if you are taking care of a person with suspected 2019-nCoV infection. > Wear a mask if you are coughing or sneezing. > Masks are effective only when used in combination with frequent hand-cleaning with alcohol-based hand rub or soap and water. > If you wear a mask, then you must know how to use it and dispose of it properly.

The kind of misinforming you are doing is dangerous in these times, especially that the official WHO standpoint is that wearing masks in a wrong way (using it multiple times, touching or taking off in a wrong way) is worse than not wearing them at all during already decreased social encounters (i.e. already staying at home, and going out at most for groceries).

Or are you stating that the WHO is lying?

Those Asian cultures have a different epidemic curve not due to mask wearing, but because a totally different social structure, prior experience concerning epidemics, preparedness, attitude towards authority & emergency measures and other factors. So it's a fallacy of cherry picking to say that it's 'because they wear masks and all our authorities are wrong'.

> Or are you stating that the WHO is lying?

yes, the page does indeed state that. what do you think of the cited research, vs nitpicking the hero image?

Out of the 7 references, most of them are journalistic articles and not actual scientific research.

The question is 'does wearing masks out in the public decrease virus spread, when social distancing measures are already in effect?'.

One linked (not cited...) research examines virus transmission and effects of mask use in a hospital setting - irrelevant for the question.

Another examines filtration properties of homemade masks, and concludes that they have little if any effect if not used with other measures, and doesn't (!!!) recommend their use.

A third one, a SCMP journalistic article refers to a Chinese scientific journal article that has been retracted.

I don't find these as very compelling arguments.

https://docs.google.com/document/u/0/d/1HLrm0pqBN_5bdyysOeoO... (linked on the page) was what I was referring to, not the list of references which I agree are not very compelling. SSC did a writeup too: https://slatestarcodex.com/2020/03/23/face-masks-much-more-t...

Thanks for sharing more detailed thoughts!

WHO’s statement itself says that the mask is helpful when you are caring for someone with a suspected infection, therefore it admits the mask can provide some level of infection protection. It likewise says the mask should be worn by someone coughing or sneezing, showing that it protects others from your germs.

The obvious answer to the “wearing masks in a wrong way” is to teach people to use and dispose of them correctly, just like we don’t dismiss hand washing because many people don’t know how to do it.

I think these statements by health authorities are simply because there has been no RCT of mask wearing among the general public and for them lack of evidence is equivalent to evidence of absence.

The decision to treat absence of evidence as evidence of absence is surely driven by evidence of absence of masks, if you pardon the pun. It's very reasonable to prioritize healthcare workers who are far more exposed than anybody else and the lack of formal, peer reviewed studies is a welcome opportunity to subdue a panic buying bidding war.

If truth was the only concern, I think that comparing the rough numbers between "masked countries" and "unmasked countries" should be more than enough to recommend masks. It's a planet-wide experiment and the control group is clearly seeing worse results. And it's not just SEA countries, there are also places in Europe that didn't play down masks, like the Czech Republic. And their metrics are looking quite good so far, with far more liberal measures than in neighboring Bavaria, except for the masks. With much of the intra-European spread being incubated in ski resorts one would expect them to be hit quite hard as well. And the Czech Republic doesn't have a magical stockpile either, from what I'm reading there's a lot of improvisation going on there regarding masks.

Speaking of improvised masks, would vacuum cleaner bags be a good MacGuyver material that's present in almost any household? It's surely better at filtering than random t-shirt cloth, but would there be a risk of ruining lungs with fibers from the bag material? The fact that they are apparently safe to force air through them in living quarters with a two kilowatts blower suggests that they don't shed anything harmful, but I'd be glad to hear any counterarguments from the wide variety of expertise present in hn readership.

I'd like to see the terms 'hording' and 'panic buying' discouraged. They're being almost universally used to simply refer to people who simply have different needs, preferences, or concerns... and the net effect is shaming people for being cautious or prepared.

The end result is that in some places people are being denied the ability to purchase up more than a few days of supplies at once, forcing repeated trips out that increase everyone's risk.

Virtually no one simply concerned for their own safety is creating a big problem for anyone with their purchases (at least not above and beyond the background level of synchronized need)-- sure, a gouger wanna-be here or there is a problem-- but that is its own separate thing.

> better at filtering than random t-shirt cloth,

Cotton is pretty good at absorbing water, if we're in the land of pure speculation it wouldn't be unreasonable to guess that it's not bad for droplets.

I agree that it's both important and difficult to distinguish between hoarding and a laudable and well invented switch to a lower supermarket run frequency. But this will create temporary shortages even in the most cooperative and well-meaning environment if everybody tries to switch at the same time. Everybody needs to put on the brakes a little for a soft ramp-up of per trip volume or else you get an actual survival of the most ruthless shopper situation.

The characterization as "hording" and "panic buying" though is resulting in bad public policy: https://www.nbcbayarea.com/news/coronavirus/san-mateo-county...

A comment I've heard from someone at a grocery supplier is that stores haven't even called in to restock many out of stock items because they're simply overwhelmed. It's not clear to me what good public policy would be to address that, beyond patience.

Telling people to hold off a bit would probably be prudent but with low item limits already being implemented by some stores and even ordinances being discussed, ... makes holding off sound potentially unwise. :( exactly opposite the needed effect.

> Speaking of improvised masks, would vacuum cleaner bags be a good MacGuyver material that's present in almost any household? It's surely better at filtering than random t-shirt cloth, but would there be a risk of ruining lungs with fibers from the bag material?

https://smartairfilters.com/en/blog/best-materials-make-diy-...

This notes it is very hard to breathe through the vacuum cleaner bag in comparison to a surgical mask. It is more effective at filtration. I’m not sure about the possibility of it releasing fibers. The analysis on that link suggests to me that for a DIY, cotton is probably the right balance although it doesn’t provide nearly the same level of protection as an official surgical mask.

Here's what makes sense to me:

* The single most effective intervention we have right now is staying home and avoiding every unnecessary contact, as authorities recommend.

* Worn carefully, several kinds of masks probably have a range of marginal positive effects.

* BUT recommending them runs the risk of (a) people over-relying on them and not following isolation protocols (b) people wearing them incorrectly for a mix of less effective benefits and added risks (c) contributing to a run on masks which constrains supply for medical workers where the benefits are more critical.

If this is all true, it can simultaneously be the case that official guidelines against masks are reasonable recommendations and that it's also a reasonable recommendation to wear masks (on top of other more important precautions).

I'm sure that masks are not the sole factor in gentler curves in those countries. They do seem to be a common factor.

I totally agree and it's likely that the public will be much better equipped after this pandemic ends. So all of us will have a box of disposable masks at home, and will be educated about when and how to wear them properly.

Right now, the average person probably only has 1 or at most a few masks, they don't dispose of them after use and probably wear (put on/off) them in a wrong way.

You know, you could have learned how to put on a mask properly within the time period you spent arguing here. It’s not fucking rocket science.

I was recently on a flight where a person on my row had difficulties taking her seatbelt off. After what seemed like two minutes the flight attendant assisted her. I'll even admit that it sometimes takes me a second to do it correctly when I try to only take it off with one hand. Despite this we still recommend that people use their seatbelts. In addition to this we play videos that instruct people on the usage of seatbelts. Imagine if we argued against recommending seatbelts because of the lack of education on using them despite never having attempted to explain how to use them.

Don't they also teach you how to put on that oxygen mask on the airplane?

> you could have learned how to put on a mask properly within the time period

I'm mostly arguing the other side here, but I should point out that well fitting an N95 mask is actually pretty tricky depending on the shape of your face.

I expect that even a lot of medical professionals don't manage it. You only really can tell that you've done it wrong if exposed to something you can smell or taste very strongly that the mask should stop.

A poorly fitted mask is almost certainly a big improvement over nothing, however.

I’m not talking about N95 masks here. I’m firmly in the camp suggesting the following: leave N95 masks to frontline health workers, and wear surgical masks when you go out. Which is at least consistent with government recommendations in Mainland China and Hong Kong (just checked, see https://news.ycombinator.com/item?id=22726566). Oh and there are two doctors in my family who recommend the same.

Tell us how to put on a mask.

We'll tell you how many errors you've made.

The Zeno mask: impossible to wear safely.

This!

The fact is that in "the wild", so many different factors are at play that it's very hard to establish the impact of one particular factor on the numbers.

In a sense, establishing the exact impact of wearing or not wearing masks is as difficult as establishing the exact impact of the population pyramid on how things evolve. Combine both and things become even more obtuse.

Worst case is that one ends up confounding correlation with causation which leads to harmful conclusions. Such as over reliance.

What you are saying is the rational sensible middle ground in this discussion. Most domain experts are very careful in the type of recommendations they make.

I'm not a domain expert, and so I put my trust in domain experts. I haven't heard any micro biologist or health care expert urge wearing masks as a basic necessity. I do hear them urge to vigorously wash hands, practice physical distancing and generally stay at home as much as possible...

There have been studies that indicate that masks are effective. There have been studies that showed no effect which also had low compliance. There has never been a study which showed people taking risky behavior because they were wearing a mask, as far as I've been able to determine.

To me that above comment sounds like rationalizing to justify misleading the public and risking their lives, out of some paternalistic assumption which has not ever been even suggested by the applicable science.

In practice, what little I've seen of people wearing masks causes a change in behavior -- additional distance, etc. from people around them. It raises awareness, and looks like it should reduce risk.

Most of the concern that people might take on additional risky actions would be adequately addressed by making it clear that masks aren't a sure thing-- especially if not expertly fitted and coupled with additional PPE and procedures.

Plenty of people are in "essential" jobs or just need to get groceries. In the bay area, many people already have used masks due to the history of fires... and many of those people are failing to use them because they have been materially and intentionally mislead by people who have, or ought to have, a professional obligation to provide honest information to them.

The loss of trust from this, as the public realizes it was mislead, will have lasting negative effects.

For an example of people relying on masks, not social distancing, here are photos of recent football matches. https://www.bbc.co.uk/sport/football/52084121

I used to be strongly anti mask, and I'm slowly changing that position, but I do struggle when I see 60,000 people turn up to horse racing in Cheltenham UK and some of them are wearing masks but doing dumb stuff -- pulling them off to cough or smoke or drink.

I can give you infinitely more examples of people neither wearing masks nor obeying social distancing, and that is in fact supported by your “example”. I hope “anti-mask” people could stop attacking the straw man already.

But the solution is "don't hold mass gatherings", it isn't "hold mass gatherings but encourage people to wear masks".

Hi,

Your comment fails to offer a counter-argument to the comment you are replying to; you are just repeating the position that the comment explicitly refutes.

> Or are you stating that the WHO is lying?

In fact, the site linked in the comment explicitly states that.

It refutes nothing — it's some layperson's uneducated opinion based on a couple of cherry picked statistics (as gombosg already pointed out).

Let the epidemiologists guiding global responses to the pandemic provide guidance and everyone else should call out anyone trying to peddle their own made up conclusions.

> Those Asian cultures have a different epidemic curve not due to mask wearing, but because a totally different social structure, prior experience concerning epidemics, preparedness, attitude towards authority & emergency measures and other factors. So it's a fallacy of cherry picking to say that it's 'because they wear masks and all our authorities are wrong'.

And you’re not cherry-picking because what exactly?

Pointing out that there are a huge number of other factors that influence the spread of COVID-19 in each country is not cherry-picking, it's highlighting that you can't simply look at said graph and say "it's because they wear masks."

Saying the difference is due to other factors but “not due to mask wearing” is cherry-picking everything else other than mask wearing.

It is not that WHO is lying, it can be misinformed or just do not know something. Previous global epidemic happened over 100 years ago, so I don't blame them for lack of knowledge.

We all have to learn and try new things, so if WHO says "mask are not helping" while there are evidences (maybe just correlation, but we just don't know for now!) that in some countries masks seems to help we should ask WHO if they are really sure. BTW: the fact that WHO pretends that Taiwan does not exists does not help investigating masks/no masks question.

"Wear a mask if you are coughing or sneezing" - sure, the problem is that even if someone breaths normally, talks normally can spread the virus. The problem with the coronavirus is that it has long incubation time. Someone might spread virus without having any symptoms.

My masks protects someone else, not me (unless I am wearing some pro stuff), as I am not spreading virus 2 meters around me, but 50 cm - maybe this is not that much, but in case of something that spreads according to power laws it might be a visible factor.

So the WHO doesn't know but some random techies on a forum do? That's absurd.

Some random techies on a forum, as well as East Asian governments and medical experts. But hey, what do they know.

But it's not an East Asian government or a medical expert who made the website that started this thread, is it? It's fasteddie31003, whose HN profile reads "Software engineer in San Francisco."

Leave the medical advice to medical experts, just as you expect the medical experts to keep their mouths shut about the advantages of Rust over Go or whether Vue is the right choice in 2020.

You mean like [0][1][2]?

[0] http://www.chinacdc.cn/yyrdgz/202001/t20200123_211390.html

[1] https://www.coronavirus.gov.hk/eng/health-advice.html

[2] http://www.cdc.go.kr/index.es?sid=a2

Well I can't judge [0] and [2] for rather obvious reasons, but [1] would have been a much better link than what was posted, and it has a much more differentiated views on masks. The website that started this thread is plain bad. The Hong Kong page [1] contradicts OP's site in its recommendation of N95 masks ("N95 respirators are generally not recommended for use by the general public in community settings because special training is required for proper wearing and removal of the mask. Otherwise the infective risk due to inadequate protection and contamination may be ironically increased." [1] vs "N95 masks are better than surgical masks" on the OP's site).

Then there's stuff like "Going in public without a mask in a pandemic is like riding a motorcycle without a helmet." That's bad because it implies that surgical masks protect you, but all the information by actual experts seems to say that they generally don't, and that their primary purpose is to prevent the spread of the infection by people who don't know they have it.

I mean, the page even admits that "We only have anecdotal research at this point" on the efficacy of masks. Yet the headline claim, "Western countries are experiencing higher rates of COVID-19 infections compared to Asian countries because of the West's aversion to wearing masks", implies direct causation between mask wearing and infection rates. Why should anyone trust someone who makes such elementary mistakes?

We need the computer people (myself included, obviously) to keep doing the computer things and leave giving medical advice to the medical experts. The OP's website is bad and they should take it down.

> contradicts official WHO guidance

A few weeks ago official WHO guidance included:

- that there was "no clear evidence of human-to-human transmission" of the virus

- that international air travel should not be suspended "because of the social disruption they cause and the intensive use of resources required" (nothing about the efficacy of such a move).

Well look at us now. Maybe, just maybe, their guidance on this topic is also flawed.

The lack of critical thinking on the issue of masks is astonishing. There are study after study[0] showing that masks mitigate the transfer of virus particles. Then there's common sense which points in the same direction.

---

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3810906/

https://www.ijidonline.com/article/S1201-9712%2808%2901008-4...

https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

God, I was so annoyed reading WHO statements and people quoting them as an authority when this first started to blow up in China.

The numbers quickly went from dozens to hundreds, and they still tried saying there was no chance of human-to-human transmission (pretty unlikely that they all ate the same food and that a virus with the main symptom being coughing isn't transmitted by coughing) and that it'd all be contained and there was no need to worry.

In this crisis, the WHO has been bending over so far backwards that it's spinning donuts to serve as a political mouthpiece for certain governments. There was panic over people being under-supplied and under-prepared, and one of the main supplies in short supply was masks. Masks aren't perfect, but even if they're reducing transmission by 10% and keeping people from touching their mouth, that's a decent effect.

I think saying “misinforming”, “dangerous”, or relying solely on the generic guidance of the WHO is a bit strong.

I think common sense prevails. Wearing equipment that filters airborne particulates will expose a person less than going without.

Personally, I would prefer being overprotected versus becoming a statistic in a WHO researcher’s Excel spreadsheet.

"Common sense" leads to empty aisles that are usually stocked with toilet paper.

I think that points more to how fragile the world economy is. You have a personal choice where you can do everything to increase your chances of survival, or go with common/generic advice that’s provided to society as a whole. I guess it depends on what your goals are.

My goal is not to be an asshole, and to survive too, by listening to people who actually know their shit instead of using their "common sense" to guess. If we relied on common sense, the earth would still be flat, and we'd still prohibit women on their period from pickling food.

Mask wearing is mandatory in several countries. This is not a situation where people are making shit up, this is a situation where you have several authorities saying different things. In the absence of solid evidence, applying common sense to evaluate the arguments of those authorities is a lot better than just picking one of the authorities and proclaiming "This is the truth!"

A grocery store aisle is about 4 feet wide.

Given the minimum 6 feet of social distancing, then there is no room for maneuvering around people here.

And all it takes is for one idiot to cough in your face without covering themselves, while you are walking past them, to get sick.

And now, you have a 14 day incubation window, to wait to see if you indeed got sick from this person.

The point of masks is that everyone must wear it, while in public. No exceptions are allowed.

This is a team effort. And all it takes is one person, to screw it up for everyone.

If someone coughs in your face then you're probably going to get infected whether you wear a mask or not, because the virus can get in via your eyes, and none of the "wear masks all the time" people are telling you to also wear eye protection all the time.

2019-nCoV transmission through the ocular surface must not be ignored: https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

And furthermore, even if the virus can't directly infect you via your eyes, the virus particles can move from the eye area to the nose/mouth after removing a mask, e.g., by touching one's face (even with washed hands) or when taking a shower or washing one's face.

> none of the "wear masks all the time" people are telling you to also wear eye protection all the time

Huh? The earliest local news article I could find[0][1] that mentioned the importance of wearing glasses and goggles was back in January. But we didn't wait for the authorities to tell us -- we did our own research, and I purchased my pair of goggles in mid January.

[0]: https://news.rthk.hk/rthk/ch/component/k2/1504801-20200125.h...

[1]: https://www.reuters.com/article/us-china-health-hongkong/hon...

We need to use our own common sense here sometimes, and the WHO are not making sense here. Kind of how they don't make sense regarding Tiwan and breast feeding. The WHO is being careful to say don't wear a mask unless you are ill, but with this virus we don't know until several weeks after we are infected, they are also mixing recommendations for non medical staff with recommendations with medical staff.

what happened to south coreea? did they only start wearing masks later?

https://www.xkcd.com/552/

Search for 'Patient 31 Korea'.

Aren't all the Countries that are doing better, also countries that eat overall less carbs? I am a strong believer that Diabetes and Insulin resistance makes a huge difference.

I mean all those countries eat a ton of rice. I would not consider any of them to have low carb diets.

Masks can also result in a false sense of security causing people to ignoring physical distancing and washing hands.

I'd much rather have people keep their distance and wash their hands regularly than wearing masks which may or may not have any effect depending on material/age/fit etc.

well, the message has arrived here. the masks haven't ;). the bad thing about the whole issue is that these are low-labor products (just look at youtube for videos), so nothing would prevent a business from producing them domestically in the US/Europe... Unfortunately it's low-margin/low-tech as well, so we optimized it away...

3M makes 1 million N95 masks every day in the US, about 1/3 of their global production. The problem is that it isn't enough to respond to the situation.

I am not arguing against wearing masks but your masks/no-masks graphic at the top does not show the full story.

I don't know why you consider China to be a non-mask wearing culture. There is plenty of evidence China is a mask wearing culture. Below [1] are articles from before 2015 about mask wearing in China. Anecdotally I have plenty of Chinese national friends and colleagues who wear masks.

As far as your mask wearing group goes, South Korea's trajectory is much like Western countries, which will also level off eventually. Hong Kong and Singapore are city states and are not comparable with large countries.

Evidence China is a mask wearing culture before 2015 (an arbitrary date to ensure no COVID-19 related articles):

https://www.theguardian.com/environment/2014/aug/10/pollutio...

https://www.nytimes.com/2012/08/04/world/asia/in-china-sun-p...

https://qz.com/299003/a-quick-history-of-why-asians-wear-sur...

https://www.webmd.com/cold-and-flu/news/20090916/best-swine-...

The graph shows first 4 weeks only. That means the early stage of infection in China when the virus basically spread unhindered; if you extend the curve to after emergency was declared nationally then you would absolutely see the effect of masks.

Edit: First 4 weeks after the 100th case actually. But the numbers are clearly delayed and reflect transmission that happened much earlier, and you can already see the curve leveling off in the graph.

The graphic seems a bit misleading, but China, Malaysia, and India seem to be deliberately not circled, meaning they are considered Mask wearing, or at least not "No masks". It could be more clearly presented, though.

Maybe. You may also just be leading the way as a cargo cultist. Maybe there's something else happening that mask wearing is a signal of. But at the moment your site is a poster child for "correlation implies causation".

I'm rather shocked at how much thoughtless agreement there is in this comment thread given the website makes only one incomplete argument in the case for masks.

Consider that in absence of real science, your site might do harm with such a bold claim.

You seriously think a bedsheet will stop the coronavirus, which is about 100nm wide?

An N95 mask doesn't "stop" coronavirus either, that's the 95 part of it.

A bedsheet would absolutely reduce viral load you spread, even at naïve assumption of the size - simply because it's an obstacle that inevitably catches some of particulate and reduces the airflow range.

But coronavirus is spread in suspended aerosol particles 3µm or so in size, which are filtered out even more efficiently by a wide range of materials.

This is a common misconception. The virus doesn’t arrive as individual viruses. If it were purely a matter of filtering 100nm particles, a n95 mask wouldn’t be very effective either - the ratings are for particles 0.3um or larger.

Luckily, people don’t generally sneeze out plumes of pure virus. They’re embedded in much larger particles, and even cotton has some benefit: https://smartairfilters.com/en/blog/coronavirus-pollution-ma...

N95 masks aren't very effective either, especially when they don't seal well. When they become moist, they're useless.

What your cloth mask is doing is to effectively spread a giant fishing net to collect all the particles around you. The moisture in your breath will help keep the viruses inside intact. You'll be constantly breathing air through that, loosening some of those particles and inhaling them. The idea that the mask would protect you makes no sense.

If you're already infected, it's a different story. The mask will reduce the amount of virus you'll be spreading around.

You might mean well, but what you did is spreading of misinformation and make the world a little worse. I would urge you to take down your website, but like e.g. anti-vaxers who by and large are well meaning as well, I doubt you will.

Nice! Really, masks can be hand made & there is really no reason one should not be wearing one during the pandemic.

As for hand made mask npt protecting you enough - well, this is actually a secondary concern. The biggest problem are people being infected that do not know that yet & if everyone has a mask this is much less of a problem, as they will contaminante much smaller area & the chance of them infecting others go way down.

The Czech government made masks mandatory in public more than two weeks ago & Slovak government followed suit quickly afterward.

So far it seems to be helping, so hopefully more states will follow suit.

Like your site, though I would suggest to put more weight on the correct use of the mask. Since the lockdown, when I go out for food supply I see plenty of people touching the mask, adjusting it, moving it on the forehead or chin just to answer a phonecall. Considering all these activities mask are doing more harm than good. Once interpersonal distance limit and hands hygiene are observed you are quite good to go. Then there are all those situations (eg. healthcare) where interpersonal distance cannot be observed and that's why countries are adopting measures in order to prioritize the adoption of the mask, especially with the shortage we are facing.

If you look at the standard equipment used in healthcare you'll notice that everyone wears mask and eye protection (goggles or face shields), because the virus can also transmit through the eye.

I'm not saying that masks are not effective, but I would be very careful with certain affirmations, such as: "going in public without a mask in a pandemic is like riding a motorcycle without a helmet", it's more like: "going in public with a mask only covering your mouth and nose is like walking through a fire while wearing a fire proximity suit and sandals".

This would work in an ideal situation. We would need 10 years of manufacturing to try this experiment for a month on a global scale.

His analysis documented on this book

A treatise on pneumonic plague, by Wu Lien-Teh https://wellcomelibrary.org/item/b19164415#?c=0&m=0&s=0&cv=0...

His mask sounds simpler than N95 masks, only replaced by the newer design during SARS period in 2013. By the way, anyone has the original design of Dr Wu's mask? Can we mass produce this design for everyone? We need it

Found answer for my question if anyone is interested to do DIY at home

page 393-394 This consists of two layers of gauze enclosing a flat oblong piece of absorbent cotton 6 inches by 4 inches. It can beeasily made by cutting the usual surgical gauze (9 inches wide), as supplied from the shops, into strips, each measuring 3 feet in length. Each strip is then doubled lengthwise so as to contain in the middle a flat piece of cottonwool measuring 4 inches by 6 inches. At either end of the gauze two cuts, each measuring 15 inches, are made. Thusturning the pad into a three-tail gauze bandage, with the central piece of wool for covering the respiratory entrance.The upper tail of one side should be passed round the side of the head above the ear and tied to the othercorresponding tail. The lowermost tail should in a similar manner be passed under the ear and tied to the one on theother side, while the middle tail should be passed over the crown of the head, so as to fix the pad and prevent it fromslipping down the neck

The secret ingredient in N95 masks (and surgical) is a very fancy modern material: melt-blown non-woven polypropylene.

This is what makes a paper thin surgical mask way better than a thick cotton one.

Totally agree, that's said most people cannot get surgical masks anymore, not to mention N95 masks. If we can learn the lesson from outbreak happened before modern tech invented, world would be a better place. We cannot produce or easily buy nanotech material used for N95 masks. However we can use whatever materials avail in our house easily. If need extra protection, add 2 layers of tissue between mask and face. Do not touch mask when you are outside. Stay away at least 2m from any human being. Do not touch anything outside. Immediately take shower and disinfect youself with 80p alcohol at home. :) hopefully most of us will not get infected, I do not want scenario in movie like Contagion or World War Z to happen for human race.

Does anyone know if there's any truth to ideas that certain metals like copper are "antibacterial"?

I am worried because I have seen stories (e.g. [1]) that claim that masks incorporating copper can be effective against the virus (never mind that "antibacterial" apparently also means it can fight viruses, which makes no sense). Basically, I am seeing an increase in people selling "masks" that are not approved and that has me worried. I would like some information about whether there is any science, for or against, to the idea that particular materials, especially metals, have any kind of "special" effect against bacteria and viruses.

[1] https://www.efe.com/efe/america/sociedad/mascarillas-de-cobr... (spanish)

Don't be lazy. Just Google search SARS-CoV-2 on surfaces and you will see that Coronavirus lasts about 4hrs in Copper, while it can stay one day in Cardboard and several days in Stainless Steel and Plastics.

So, yes, there is something special about copper. But copper is not a virus killer (i.e. kills them at contact), it justs seems that viruses don't survive that long in copper. This has been known since ancient times (where Copper pantry and utensils was preferred over Steel).

The New England Journal of Medicine. The scientists found that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detectable in aerosols for up to three hours, up to four hours on copper, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel.

https://www.nih.gov/news-events/news-releases/new-coronaviru...

The anti-microbial effect of copper has been known for decades, which is why it fathoms next that fixtures in hospitals are still made from steel.

Millennia, actually. There is clear evidence that people understood the medical importance of copper in ancient Rome, and even some evidence of Bronze-age Egypt and ancient India (which is to say it's clear copper was used in medicine, but it's unclear people had evidence it helped). That's 2000 years definitely, and 5000 years possibly.

Prior to disinfectants, hospitals used a lot of copper. It only became a relic with industrial-grade disinfectants.

That said, the timelines aren't such that it seems useful for use in masks. Viruses and bacteria survive on copper for hours, instead of days. There are a lot of uses of copper which aren't grounded in science and make no sense (superstitious nonsense).

But copper for things people touch a lot? Doorknobs? Definitely makes sense.

It's simply that copper is too expensive to use on an extensive scale such as hospital fittings.

Copper costs about twice as much as stainless steel per tonne and that is with current demand levels. Squeezing supply would raise that significantly.

Annual worldwide copper production is 18M tonnes and increasing. Most of it is used in plumbing and wiring. Taking a little bit for hospital hardware wouldn't impact demand much, and the extra cost would be a rounding error compared to all of the other equipment that goes into a modern healthcare facility.

> Don't be lazy.

Thanks, your answer was very helpful. However, I feel you could have given it without this prefix, without any detriment to the content of your post.

The proper name is the oligodynamic effect [1], and that seems well-proven to me at least but I'm certainly no expert. It seems the effect does cover viruses too, and copper has such an effect [2].

[1]: https://en.wikipedia.org/wiki/Oligodynamic_effect [2]: https://en.wikipedia.org/wiki/Antimicrobial_properties_of_co...

Here's an interesting reference (viruses): https://www.sciencedirect.com/science/article/pii/S030438941...

And more generally (bacteria): https://en.wikipedia.org/wiki/Antimicrobial_copper-alloy_tou...

EDIT: https://en.wikipedia.org/wiki/Antimicrobial_properties_of_co...

> By the late 1870s, scientists learned about bacteria.

Bacteria had been discovered in the 17th Century, the moment the microscope was invented. I think by Robert Hooke, but I could have misremembered that.

What was new in the 1870s was the germ theory of disease.

Not a single mention of the disastrous pollution caused by the disposal of millions of non-biodegradable single-use masks into landfills. Yes, they are a big innovation. Yes, the tech is saving lives. But come on, this is 2020, not one mention of pollution?

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