I wish the media and government would have spent more time in educating people in things like how N95 masks work and that it isn't like a coffee filter. Even thought the pores are larger than a virus the masks are statically charged causes smaller things to get trapped. Many people don't know this but probably had an interaction with static electricity sometime in school and would understand it if someone explained it. Instead people get put in a bucket and no dialog is possible.
Education is key to understanding. You can't reach everyone most.
> Even thought the pores are larger than a virus the masks are statically charged causes smaller things to get trapped.
Even filters that aren't statically charged stop particles that are smaller than the gabs between the fibers. There are actually several mechanisms by which a filter can stop a particle.
1. Big particles don't fit between the fibers of the filter. Think fish in a fish net. This is called sieving.
2. Particles too small for sieving but heavier than the surrounding flow don't make the turns as well as the surrounding flow when the flow goes around the fibers. The particles can get embedded in the fibers. This mechanism is called inertial impaction.
3. The smallest might be too small to actually be affected much by the flow of the surrounding fluid through the filter. The move by diffusion, and many will randomly hit the fibers and get stuck.
4. Particles too big for diffusion but too light for inertial impaction still can run into fibers and get stuck. This is called interception.
5. As you mentioned, some filters have an electrostatic charge which can help trap particles.
The effectiveness of sieving, inertial impaction, and interception all follow S shaped curves that start out low for small particles, then at some point start rising, and then level out. The sieving curve's rise is almost vertical. The rise for inertial impaction is steep but not nearly as steep as it is for sieving. The curve for interception's rise is much more relaxed.
The effectiveness for diffusion goes the other way. Much more effective for very small particles, then above some size drops down and is low from then one.
When you put all these together, you get a curve that is effective at the small end, and at some point as size goes up effectiveness drops, reaching a minimum, and then rises again to reach high effectiveness for particles above some certain size.
The reason 0.3 microns is used for many HEPA filter ratings is that is in the middle of the low part of that U shaped curve, so when you get a filter that removes, say, 99.97% of 3 micro particles, it should actually do better for both larger and smaller particles.
I’m not sure there was any popular doubt over the efficacy of N95 masks. The problem was rather getting one - marketplaces like Amazon restricted access to masks if you weren’t affiliated with a hospital. So you were left with sketchy deals and weird vendor sites.
I suspect Amazon killed quite a few people over the last year by restricting access - supply scaled pretty quickly.
According to the data presented, surgical masks are still highly effective even after converting the scales to linear. Add social distancing on top, it is almost as good as N95.
And I very much doubt that N95 masks are effectively utilized by the general public considering how many poorly fitted masks I have seen over the past year.
Before the pandemic there had been several studies looking at the efficacy of N95 vs. surgical masks at preventing the transmission of influenza in hospitals. Most of them never got anywhere because it was soon realized that even doctors and nurses cannot be trusted to wear and change masks properly during the daily routine. Let's hope things have improved by now.
> And I very much doubt that N95 masks are effectively utilized by the general public considering how many poorly fitted masks I have seen over the past year.
I agree. When people can't even wear surgical masks properly, there's no hope with an N95.
> Most of them never got anywhere because it was soon realized that even doctors and nurses cannot be trusted to wear and change masks properly during the daily routine. Let's hope things have improved by now.
At the very least, everybody is washing their hands. Before Covid, you couldn't even get all the doctors to do something even that simple.
Unfortunately, a few of my friends fell victim to the Qanon conspiracy bandwagon and the fact that mask pore size is wider than the virus was heavily circulated as a reason for mask ineffectiveness.
Everyone is having assumptions about these observations. The conclusions might not be always right, but at least the observation is real. And when you observe that mask mandating states don’t do significantly better than mask-free states, then a curious mind rightfully starts pondering. No need to unterstand conspiracy theories (a difficult topic) to understand that science isn’t getting it right yet.
> And when you observe that mask mandating states don’t do significantly better than mask-free states, then a curious mind rightfully starts pondering.
If this is true, which I haven't confirmed, wouldn't that say more about the effectiveness of political policy rather than about masks themselves? When we have seen throughout the pandemic that healthcare workers have a dramatically lower rate of infection compared to the general population, despite having more direct contact with infected populations, it is clear to the that proper precautions including protective equipment (principally masks, for a respiratory disease) can impede COVID transmission heavily. With that being the case, the question becomes: has mask policy been effective in getting enough people to wear masks properly and consistently, in states where it is mandated?
That wasn't a Quanon conspiracy: that was misunderstanding that I saw plenty of mainstream doctors and other health professionals promote. What it showed is that either they were intentionally lying - which I kinda doubt - or that they were so confident in what they had heard that they never bothered to do any research for themselves. Just reading the relevant wikipedia pages carefully would have corrected that misunderstanding.
This is your not frequent enough reminder that "doctor" is not a synonym for "scientist", or more specifically epidemiologist.
Medical doctor's are basically mechanic's for the human body. The human body is complex, so this is a high bar to clear and an important function, but it doesn't magically grant them knowledge about concepts outside that field.
The US seems to have relied heavily on cloth masks, even long after the shortages were over. From my understanding, surgical masks are much more effective (while often being more comfortable) than community/cloth masks. (I don't have a source for this on hand, but the German government did ban cloth masks/require at least surgical masks in many areas for this reason.)
I suspect a lot of that was out of a desire to not appear as backtracking on a previous position.
This was an education issue. There were KN95 and KF94 masks available for purchase. I bought KN95 masks off Amazon sold by Amazon proper and later switched to KF94 when they became widely available. Both masks have similar performance to N95. Someone of the KF94 masks i bought showed 99% filtering effectiveness in government testing.
You could get halfway with other solutions. The 3-layer design with the synthetic layer in the middle tries to achieve the same idea. It's not going to be as effective as a certified N95, but it's better than a simple cloth. Not sure how common the idea was globally, but it was quite common to make them in Australia.
Unfortunately there is _absolutely_ popular doubt about this, and every other thing you likely think is obvious about covid and the world. I don't think educating people about masks is really the answer though. I don't know what the answer is, or if there even is one. Feel like our society is coming apart at the seams.
I don't think people need to know how they work. They just need to know that those are what doctors wear and that they are very, very effective. And much better than a mask you make from ad hoc materials.
Once N95 masks became readily available and cheap, it was (and is) mysterious why people weren't being told to wear them to protect themselves instead of wearing whatever was at hand to sort of protect themselves and others.
Last I checked in Canada, N95 masks are still about 3$ a pop for disposable, single use masks from industrial distributors. Pre pandemic, we bought 3M 8210s for about 15 cents in boxes of 160. I wouldn't call the current situation available and cheap.
Oh, and if you thought surgical masks were mildly uncomfortable, N95s are an order of magnitude worst. They pretty much need a perfect seal with your face and the 3Ms use a really tight rubber band to achieve that. 2 bands, actually.
I currently work on site and wear surgical masks all day, it's fine. Not sure I would want to do the same if it was N95s.
3M 8210s are US $26 for 20 now. $1.30 per mask seems pretty reasonable to me, but I've never bought them in industrial quantities so don't have that anchor.
I've worn N95s for hours (actually P95s which have a nicer seal) and I agree that they're less comfortable than less effective alternatives. But it is a bit curious that people are concerned enough to be wearing their homemade mask alone in a car or walking outside by themselves but are unwilling to endure the slight additional discomfort of a known effective mask.
Not to mention fervently touching mask surface that could be contamination might not be a good idea, especially if there is a chance you might then touch your eyes.
Grant me the steel man. What's the mental model of the people wearing them outside on a walk in the woods or on a beach? Not the inconvenience of taking them off between stops at the bank and the drug store.
I don't know, but who cares. Maybe for pollen and dust allergies.
Part of the problem is everyone feels the need to judge others. Why does it bother you that people wear masks on the beach? Why can't you just let them be?
I don't care what the others are doing per se. In fact, I think it's optimal if everyone else would wear a mask all the time.
What bothers me is that the sort of inconsistency I described is emblematic of the same muddled thinking that the CDC has demonstrated throughout. This is a problem for a number of reasons.
When people don't understand the reasoning behind a policy they are less likely to comply with it and it will lead to excess deaths.
Another reason is that, if no explanation or an incoherent explanation is given for a recommendation, people have to decide whether to follow it based solely on trust or the authority of the recommender. I don't think either of these is good for the long term health of society. You can see how this problem has manifested itself in the resistance of many people to being vaccinated or wearing masks.
They are expensive, and I do not reccommend wearing them. I do not reccommend doing anything, expecially anything that has a high chance of bringing unknown costs.
If you tell me how something works and it fits within my mental model of the world then I will trust you. I will add this information to my mental model of the world.
If you tell me something works but can't explain how I will consider if the claim is worth evaluating then attempt to understand it myself before accepting it.
If you tell me to trust you with no explanation I will immediately distrust you.
When Semmelweiss invented handwashing, all the other doctors ignored him because they didn't like his model, even though he had empirical evidence.
Similarly, people like to argue against things like the minimum wage because it doesn't fit some economic model, but they don't realize those models are made up post-hoc to fit older real world data that turned out to be biased and incomplete.
Oh, and the West had to deal with scurvy for hundreds of years after discovering the cure (lemon juice) because we'd invented the food poisoning and germ theories of diseases and so we refused to believe you could cure one with food.
That's reasonable and also what I would like. But what is the mental model of someone wearing their mask alone in the woods or in their car?
So, yes, we should explain why an N95 is better than a handkerchief, but it seems like there are plenty of people who don't care about the details and just need to be told that one is more effective.
The mental model of many wearing masks "alone" is that it's more annoying to take the mask on and off all the time than it is to just leave it on. Also, touching the mask constantly leads to concerns about contaminating your hands and then spreading that.
> Once N95 masks became readily available and cheap, it was (and is) mysterious why people weren't being told to wear them
Because they're difficult to wear. There are a bunch of photos on social media of HCPs who've got bruised faces after correctly wearing N95 / FPP3 for a day or two.
Tens of thousands of doctors manage to wear them every day without injury. So color me skeptical in finding social media testimony less than persuasive that a real issue exists with the proper use of masks.
Bless your soul, but what I've learned from the way we handled the pandemic worldwide (and are still handling it) is that information that's readily available and should in theory reach everyone, flows ridiculously slowly, even among specialists and political figures, it's easily corrupted and distorted, and a loud ignorant minority counts as much in the public discourse, as the voices of millions of reasonable people.
I'd say we have more evolving to do. Both biologically and socially. Individually (some) of us are relatively smart. Together we're as dumb as a piece of wood.
Absolutely. Considering how long it took CDC and WHO to even acknowledge airborne transmission, even though the Chinese were very clear about it from very early on.
"even though the Chinese were very clear about it from very early on"
I'm not sure this adds as much credibility as you seem to think.
See (for example) - propaganda videos of people dropping dead in the street in Wuhan in early 2020.
I'm not defending what they did, but let's make the facts clear.
Initially (december?) they denied there was human-human transmission, and tried to down play magnitude of the virus.
And once Wuhan was locked down, they down played how harsh it was, cut out the media (with the excuse of not causing panic).
But even before Wuhan locked down, they allowed the release of the virus sequence (Jan 2020), their mitigation efforts in Wuhan (the field hospitals built there, the thousands of doctors sent there, the treatment strategy the doctors used, what worked, what didn't), the air borne transmission, treatment methods, and all of that.
I was following this pretty closely, and the Chinese released very relevant information very early on.
But when Italy got hit, it was like they didn't even bother listening to anything the Chinese already put out. The Italians re-discovered pronation, low oxygen flow intubation, anti blood clot medication, etc.
Blaming the Chinese health authorities for not being credible is fine. But simply discounting everything they said is stupid. And completely ignoring their information even with mounting other evidence because "The Chinese are not credible", is doubly stupid.
It's like the world put on stupid blinders, and just wished that the Chinese were lying and Covid would just disappear magically.
I don't suggest ignoring everything the Chinese health authorities said, that would be ridiculous. "Take everything China allows to be released to the West with a pinch of salt" is a sensible starting point though - you can use it as an input, but you have to be more skeptical of information fed to you by a communist-controlled authority than you would otherwise be, and you certainly don't add credibility by pointing out "the Chinese authorities said so".
My point is that even the "untrustable Chinese" were saying airborne transmission at the outset. And other evidence that they were right came pouring in from other countries like Korea, Hong Kong, Italy, etc right from the start.
The CDC and WHO's decision to deny airborne transmission 14 months into the pandemic is purely idiotic.
So who do I trust now? Independent Scientists. Basically Twitter, ffs.
There hasn't been a single case reported in the West, of anyone dying instantly in the street of COVID-19. Ergo, videos filmed within China, allowed by the authorities to be viewed outside China, purporting to show this scenario, are the very definition of propaganda.
Accusing others like this is not allowed on HN, and we ban accounts that do it, so please don't.
"Please don't post insinuations about astroturfing, shilling, brigading, foreign agents and the like. It degrades discussion and is usually mistaken. If you're worried about abuse, email hn@ycombinator.com and we'll look at the data."
True, but there was many other reasons to think masks would work. Its demonstrated efficacy in other coronaviruses and the cultural evolution of dense Asian countries to use masks as a way to combat virus transmission. The WHO and CDC behaved liked total idiots, setting the burden of proof way too high for what should've been a pragmatic, common sense decision made with some uncertainty. Not atypical of bureaucrats to miss such a layup.
I don’t think they were total idiots, at least not from the angle you’re pointing out. The CDC knew masks were effective, but they wanted to make sure masks were reserved for healthcare workers. Remember at the time nurses were given a single mask to use for multiple days, and many hospitals had drives to collect donated masks. The CDC lied to prevent the general public from making the situation worse. Was it worth the long-term loss of credibility? It’s easy to say no, but we’ll never know the counterfactual. For all we know some other issue would have become as politicized as masks were.
To me, this was a glaring reminder that public health deals with more than cold hard science. It’s about ensuring public health first and foremost, given the realities on the ground. See harm reduction as another example. Again, I’m not sure they made the right call here. But it wasn’t due to ignorance.
It's hard to attribute the same charity to the WHO. They were dragged kicking and screaming to mask recommendation and this happened many, many months into the pandemic, well after any concerns of mask shortages were alleviated.
I see your point about the CDC. But they should've recommended home made masks. Other countries did that. They messed up big time. It's impossible to know the counterfactual with perfect confidence, but we can make a sound judgement given what we know.
Yeah, it's disappointing to see how I still see people wearing their masks incorrectly, e.g. just over the mouth and not covering their noses.
Sometimes I think human beings are advanced, but then I walk into a public toilet and I see evidence how many are still no better than animals. It's a simple technology, urinate into the hole where the water can wash it away and we'll remain hygienic, but a lot of people still fail at that.
There are a couple of defensible reasons that people don’t put their mask over their nose outdoors. Firstly, if you wear glasses, then on humid days your glasses can fog up to a degree that you can’t even cross the street safely.
Secondly, in some countries the public has chafed against laws requiring outdoor mask wearing in places that are not even remotely crowded. (In my own country, the same scientists advising the government on the COVID response have also opposed this law and urged the government to overturn it, arguing that it is clearly unscientific and only undermines the government’s credibility in getting the population to observe the public-health measures that really matter.) At that point, wearing a mask in a half-ass way is a way for the population to signal their discontent. It has happened that such laws were lifted when ruling parties saw mass flaunting of them, because such strictness might cost them the next election.
To elaborate, I saw these people inside a supermarket, where it's probably in their own interest to wear it properly. And no they weren't glasses wearers.
But yes governments just repeating unscientific rules also annoy me, I agree in the empty outdoors masks are most probably unnecessary. (This statement is hedged because hey, I'm not an epidemiologist). They emphasize the "6ft apart" stuff but not the ventilation of indoor places...
And they say outdoor dining is okay, so restaurants put up tents which are poorly ventilated, and hey, the fucking things are outside, that follows the rules, so that means they're safe, right?
I should just join Wonko the Sane outside the asylum...
This is just something that happens with masks. I think you're reading too much into it.
In years past in Japan, where mask-wearing was always common, I noticed that just covering the mouth and not the nose was quite common. It still covers most of what people are trying to cover (odor, droplets). Which would still help for the worst contributors to covid too. If people are feeling claustrophobic or legitimately having difficulty breathing, I think it's an acceptable compromise.
Also, if people are talking a lot, then the mask tends to get pulled down off the nose constantly due to jaw movement. Hence in Japan you'd see store clerks and people in such roles often wearing the mask that way. Also this happens practically every word for many kinds of cloth masks. So if you see a public speaker somewhere with a fancy cloth mask not covering their nose (a shaming target I've noticed on twitter etc.) they probably can't help it.
I can't help but look at some peoples' rejection of public health guidance in the US as "not a bug/won't fix."
The relevant authorities (including traditional mainstream media) injected politics into the public discourse, which destroyed trust in what should be a normal public health process. Not only that but the relevant leaders of agencies decided to try manage the supply of masks through "steering" the public by downplaying the usefulness of masks.
Distrust of untrustworthy leaders is a feature, not a bug.
I get where you are coming from but something I've learned from this pandemic is that "wear a mask" is too complex and burdensome for a significant proportion of people in the west...
The only time "N95" was uttered was last year, when we were being told: 1. Masks aren't needed; 2. Don't buy masks, healthcare workers need them.
It's unfortunate that we didn't go back to talking about proper masks before people started knitting them and making them out of rags and beads. One wonders what difference it might have made.
You are being very generous in assuming the people in charge want you to be educated. It seems to me they wanted you to run around with a (relatively) useless cloth mask so they could horde the most effective masks for themselves.
The problem is wearing mask is annoying and uncomfortable. If I have to choose, I'll choose the increased risk of covid all the time rather than wearing mask.
A big part of why they are annoying and uncomfortable is the lack of one-way valves to make it easier to breath in them. In industry, when you actually need to wear a mask/respirator, they almost always have valves.
Unfortunately, we got stuck on the "wear masks to protect others" narrative, and people who actually were at risk were prevented from wearing much more effective, much more comfortable, masks that would actually work well at protecting them. Eg here in Canada, it's illegal to wear a mask/respirator with a valve on a plane.
I don't think it is an unfortunate narrative. two people wearing masks without valves is twice the reduction in likelihood that either one gives the other covid.
If someone does have covid the mask without the valve will greatly reduce the concentration of virus particles in the air around them. I think that is working as intended!
Masks that aren't worn correctly tend to have very low efficiencies, because the air just bypasses the mask at the edges. Depends on many factors like the type, how hard you are breathing, etc. But filtering just 20% of the air breathed in is quite possible. And let's face it, people intentionally wear them incorrectly all the time because they suck to wear.
If you and I both have 50% filtration, that's the equivalent of 75% filtration. For the person who is vulnerable, that is much less effective than just wearing a 95% minimum filtration valved N95 mask/respirator properly.
It's just ridiculous that an elderly man on a flight, sitting next to a healthy 15 year old more likely to be killed by a flu infection(1), will be told to take off his valved N95 respirator here in Canada, to protect that 15 year old. I have friends who have seen this happen first hand.
With the typical masks available to and worn by ordinary people, exhalation pressure seems to cause a lot of air to bypass the mask too - except that instead of doing it via a well-designed valve that redirects the airflow somewhere sensible, it blows out the top and steams up glasses or out the sides and towards whoever's standing behind you.
I'm my state we have a choice now and I still wear one most places except the gym. That's where my comfort vs risk threshold crosses. On that note one thing that's odd that I've observed in mixed mask rooms is that I don't like exposing my face to people who aren't exposing theirs. It's like my smile, a sign of peace, can't be reciprocated so I'm making myself vulnerable at their expense. I'll don a mask in mixed mask rooms not because of conformity per se, but what feels like defensiveness. My simian brain is thinking "you don't know if these are friendlies." I'm looking forward to any future psychological studies that explain this phenomenon.
Why does then the states with the highest mask use (CA, NYC) have much higher covid positive rates than states with some of the lowest mask use (Florida, NYC)?
> Education is key to understanding. You can't reach everyone most.
N95 masks improperly used will hold covid for 24hrs and spread them by the incessant touching most people do of their masks before they touch other things.
Education only works if the means as deployed are likely to have a positive effect, such as surgeons in a strict hospital settings (where they are still used the wrong way as most people still touch the mask).
> Why does then the states with the highest mask use (CA, NYC) have much higher covid positive rates than states with some of the lowest mask use (Florida, NYC)?
They don't. Stop spreading misinformation. (Also I love that in this repeat of your misinformation, you accidentally typed "NYC" where you meant to say "Texas". And it would behoove you to learn the difference between a city and a state.)
The confirmed cases to population is 10.3% for NY (not NYC- 2.08m cases to 19.4m population), 9.5% for CA (3.77m cases over 39.5m population), 10.1% for texas (2.93m cases over 29m population), 10.6% for Florida (2.29/21.48).
So to be accurate the confirmed covid cases to the population is about the same in states with and without mask mandated as well as other strict social distancing measures.
> Why does then the states with the highest mask use (CA, NYC) have much higher covid positive rates than states with some of the lowest mask use (Florida, NYC)?
Even if that was true, places that were hit hardest by the pandemic tended to impose the most severe restrictions.
It's like finding that crash barriers are installed on roads with the highest accident rate and asking whether crash barriers are useless.
People have traveled and moved extensively to Florida as well as TX from NY and CA, so any high-spread virus would spread to Florida and CA then spread within them.
If masks and other strict lockdown measures were effective then by now open states such as Florida and NYC would see much higher death as well as covid case rates. See other comment I made in parent thread showing its about the same.
Strict lockdowns are effective. It's a virus that spreads through social contact. You restrict social contact, you reduce spread of the virus. It's not plausible to claim they're not effective.
This feels like an argument from 12 months ago. They've demonstrably worked in Italy, the UK, New Zealand, China, and so on. They were the primary tool to constrain virus spread until vaccines came along.
As I've shown outcomes on covid cases are equivalent in populous strict lockdown states (NY, CA) and open states (Florida, Texas). Death rate to confirmed covid cases is about 1.6% for all of these except NY that has 2.6%, controlling somewhat for differences in testing.
We immediately face this issue:
You should not act on information, or even knowledge.
You should act on WISDOM.
Wisdom is hard to gain, and yet it proves itself time after time to be better than the other forms of truth.
Education is not the key; That would be wisdom.
I do admit that most of what they teach is falsehood, and it would be better if it were truth.It would be better of there were no education at all than what we have now. In fact, it would be better to have no education system at all than to have a good education system that is liable to deteriorate. This is especially true when that system is a cost and a burden to and on society.
Your information, however, is hardly better than the "n95 is coffee filter".
There is no good proof on how airborne viruses are transmitted!
Wearing a mask may do nothing, or it may do everything(Well, it can't do everything. Masks haven't stopped gov't from the vaccine)!
It is likely that much of the transmission is not even caused by the oral and nasal areas, but instead is due to fecal aerosols.
Our best solution may be the abolition of apartments and shared housing. SOme sort of filter should be put on the toilets, not on our faces.
Cleansing chemicals(like bleach) should be put in the toilets, not in our arms.
Let us remember that choices should be made carefully, with consideration, and only once all of the facts are present.
Let us not be hasty-We must wait until a length of time has past in which effects which take alonger time to present themselves are presented.
This may require the foregoing of many necessary things. But such is the cost of life. Such is necessary to avoid death, or things much worse.
I wish the media and government would have spent more time in educating people in things like how N95 masks work and that it isn't like a coffee filter. Even thought the pores are larger than a virus the masks are statically charged causes smaller things to get trapped. Many people don't know this but probably had an interaction with static electricity sometime in school and would understand it if someone explained it. Instead people get put in a bucket and no dialog is possible.
Education is key to understanding. You can't reach everyone most.