Many hospitals are wearing two masks but for slightly different reasons. N95s are almost certainly sufficient to protect you if they’re worn correctly. If you’re an employee at a hospital, they’ll do what’s called a fit-test to ensure you can get a full seal on your mask. It involves a strong-smelling substance outside the mask and if you can smell it, your mask hasn’t sealed properly.
The second (often cheap surgical) mask is merely to protect the more expensive N95 since they’re in relatively short supply still. Surgical masks have plenty of supply and are cheap so they can be tossed out in between patients to limit the risk of cross infection.
Outside of healthcare settings, N95s are rare and often worn incorrectly so a second mask over the first is actually providing moderately more filtration and protection.
No, but double masking will help until the real solution is acknowledged and implemented.
Everyone should be wearing properly fit and sealed N95 masks from well known brands like 3M. Pieces of cloth that vaguely cover the mouth and nose but leave giant gaps do not protect the user very well. A proper 3M N95 that intentionally worn un-fit, with large gaps along the nose and sides becomes an ~N40.
Unfit masks of any type, and fit "KN95" masks that have such a high pressure drop all air goes around the edges (they suck in and out) barely protect the user of the mask at all. Yes, they're better than nothing. Much like wearing sandals in a blizzard is better than being barefoot. But it won't stop your toes from freezing off and unfit, unrated masks won't protect you from aerosol infection.
The solution of two masks hardly helps if there are still large open apertures along the sides. The only real solution (within the USA) is to use the defense production act to force 3M and Ameritech to fully hire-up and run their factories full time, as well as building new electrospun N95 mask factories. Every single person in the USA (and canada, and elsewhere) should have enough N95 masks to use a new one each day. That is the only solution to the mask problem. Double masking with bad masks is just more security theater.
It's been an entire year. The excuse the real masks are only for hospital personel is no longer valid. The people deserve, they need, real masks.
It's a narrow line you have to walk when relaying the science. Things are so polarized a nuanced/realistic view is hated by both "sides". But stick to the truth, eventually, and even if it's 3-6 months late, the press and eventually government will catch up to reality.
People were told last year that home made cloth masks were perfectly fine. I applaud skepticism at new claims, made without scientific backing, that now not even one mask is enough.
My guess is that in order to increase the number of people wearing masks, they're trying a new scare tactic: maybe you should wear 2 or 3 masks. Maybe they hope that will cause people to wear at least one.
I know several virulent anti-maskers and telling them to wear 2-3 masks will just make them dig their heels in further. They’re literally laughing out loud at all these articles now.
It's pretty polarized in the US right now, so people will naturally lump people into the "pro-mask" camp and the "anti-mask" camp, and the latter is closely tied to a lot of anti-science views. It's an unfortunate heuristic we use a lot. You'll get it less if you provide more nuance and context, or signal that you do take things seriously. "We need to start using N95 and surgical masks because cloth masks don't work." won't get you called anti-science. (Maybe impractical, though surgical masks pretty widely available.)
To respond to your specific statement, part of the problem is that "don't work" is too blunt and not quite true. "Don't protect the wearer" might be true. "Barely protect the wearer" would be. "Don't provide strong protection for others" also true. But even a poorly fitted cloth mask is almost certainly better than nothing. (Of course, I'd also believe that they likely provide a false sense of security, leading to risk-taking that more than offsets their benefits.)
This ties in with one of my biggest frustrations of the whole pandemic, at least individual behavior: so many people's risk analysis is just sorting things into "safe" and "unsafe", rather than thinking in degrees. "Cloth masks don't work" is unhelpfuly binary and non-specific. (Though including "poorly fitting" makes it better -- "ensure proper fit" is actionable advice.)
And while efficacy of "cloth mask" vs. N95 is good to know, "cloth mask" is a super-broad category. I'll occasionally see people specify "single layer cloth masks", but the only single-layer cloth masks are gaiters, and even those are frequently folded over double.
How good is my 2- or 3-layer cloth mask? What materials should I use? (To be fair, I have seen some people answer this question.) Is it relevant that I can barely feel my breath through it or around the edges even if I blow hard? How much of a difference does fit make?
Ideally we'd all have and use good quality N95s, but we shouldn't make perfect the enemy of the good. We need information that will help us do better, rather than a binary "N95 good; everything else bad."
I think they may help by reducing the velocity of the particles that are ejected from a persons mouth, making things safer for people around them. But a loose cloth bandana around your face probably won't stop a virus.
Anti-science means that you don't follow the given narrative in this day and age. There is very little solid science behind most of the covid measures. Basically we just trusted what China told us and followed suit.
Interested to hear you say KN95 masks are much worse than N95. Aren’t they the same specification? Assuming of course you can find a legitimate non-counterfeit one on the FDA/CDC list.
When you say a KN95 barely protects the user at all, are you stating that they are worse than a cloth/surgical mask? I recently purchased some kn95's to wear instead of the surgical masks when these variations started to pop up.
Sorry, I didn't meant to imply all KN95 are bad. I only mean the specification means very little in north america and of all the KN95 masks I have tried they have too high of a pressure drop across the actual filter to do filtering. When I use medical tape to seal them to my face they puff out and suck in dramatically. A low pressure drop N95 mask, when sealed with medical tape will barely move. You can even feel drafts from air conditioning through it.
What I am saying is that KN95 types in the USA are of such variably quality they are not a good choice. Use local standards and brands.
The idea is to rotate the masks, not to throw them away. You wear one then let it sit alone, without being touched, for a week or more. The next day you wear a new mask then do the same to it. A week later you can go back and wear the original mask again.
Throwing them away after 1 use would be silly. I personally have enough masks, and few enough indoors engagements, to let my N95 sit for a full month between re-uses.
That's nothing compared to Starbucks coffee cup waste precovid.
And besides if you're arguing that we need to reduce landfill you shouldn't be advocating for any sort of anti-virus measures as any sort of population reduction will do more to reduce landfill than any sort of reusable mask could ever hope to accomplish.
We already have more deaths from COVID than ww2 yet...crickets on the mask production front. I’m guessing it is because in a year when COVID is not a thing anymore it will not be profitable to have that much capacity and corporations do not want to ramp up that much.
Also making masks is probably not the best strategy. If we used reusable p100 filters that would be much more effective even for the general public. I used to work with fiberglass wearing a similar respirator with an organic vapor cartridge and it was usable for hours at a time, so no idea why we haven’t started using these in high risk [grocery/prisions/schools] instead of KN-95/N-95 of which there is a counterfeit mask problem.
I applaud any initiative to make life safer, but given that most accidents happen at home, why should you ever take your helmet off? They are literally killing people by telling them to only wear them outside!
Glad they are pivoting to this 'Upgrade your Mask,' approach. Noticed a few months ago a lot of energy seemed to be spent on encouraging the final 5-7% of people to wear masks. Also noticed many people 'wearing masks,' were still wearing ineffective or fashion-first masks. So you had 5-7% unwilling to adopt the health practice, but another 20-30% with proven willingness, just poor implementation, yet all messaging was focused on that smaller, resistant audience.
I would assume that if you wear two masks, and the lower mask doesn't fit properly, you make things worse. Air will take the path of least resistance, and the more resistance there is in the filtering layers, the more air will leave using other ways.
The hospitals have been doing this from the beginning. There must be some truth to it. I think it's simple probability. A n95 mask lets in 5% of particles getting though. Layering two masks should effectually make a n99 mask ((1/20) * (1/20)) = 0.9975 The added mask only adds n4.9. It's probably a more effective use for second mask to go to someone who has a surgical mask.
Let's do the math for surgical masks which are like n20. Adding two n20's gives you a n40, which is marginally better than the n95 double masks.
Let me vent by saying I was on the pro-mask side when the CDC and WHO were against them, I made a website that went viral and got 7 million view letting people know your government officials were wrong. I had my account banned from Reddit and Facebook over being pro-mask. I even got contacted by the CDC to think about taking down the site. I told them to fuck off. When this pandemic is over and we can do a post-mortem on the pandemic the CDC and WHO will have blood on their hands for the poor messaging around masks.
I for one have been double masking n95's for a while.
Did they really? We all know more layers is better for this kind of diffusion filter. However, the other key variables are fit and leakage, where double masking tends to not help at all with respirators, but may with very soft masks.
We don't have any data that it does, though.
Usually people use sub par (cloth, surgical), badly fitted (loose rubber bands, misfitting nasal) masks or wear them wrong - the classic being a mask not covering the nose.
That's not how masks work.
The masks rating is mostly a function of leakage not filter material for the particles of concern (biological aerosols) and using multiple harder respirators can compromise fit or provide no benefit.
The rating percentage is for specific test setup. For biological aerosols, the result is quite different in that small particles are stopped by diffusion, and the filter rates tend to be better than rated for masks, as long as leakage is low.
Now, the situation is different with weak filtering materials such as used in surgical or cloth masks, but the result is not additive either.
Have you actually tested that the specific double N95 configuration even provides single N95 protection? (Esp. leakage) No? Then better not mess with the design.
A couple days dfter Fauci said "If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective." Which is quoted in the article he said: "There are many people who feel, if you really want to have an extra little bit of protection, maybe I should put two masks on. There's nothing wrong with that, but there's no data that indicates that that [double masking] is going to make a difference, and that is why the CDC has not changed their recommendation."
For what its worth, I've seen KN95 masks and N95 masks being in stock from trustworthy retailers at reasonable prices (~$1 per mask) so I picked some up. My layman's assessment was that they did a significantly better job of sealing around the sides of the mask than the cloth masks I'd purchased early on or the surgical-type masks I'd more recently switched to. They also had the side benefit of not allowing air to escape out the top and fog up my glasses.
Double masking - using a N95 and a cloth mask - works better because it protects you and others.
The N95 protects you, but many N95 masks have exhalation valves that blast particles away and make it easier for you to breath.
The cloth mask on top of the N95 protects others, by reduce the amount and distance of particles. This is especially true for N95 masks that have valves.
If we are taking this seriously, then surely wearing some swimming goggles would have more benefit, considering that you can be infected through your eyes.
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[ 3.0 ms ] story [ 102 ms ] threadThe second (often cheap surgical) mask is merely to protect the more expensive N95 since they’re in relatively short supply still. Surgical masks have plenty of supply and are cheap so they can be tossed out in between patients to limit the risk of cross infection.
Outside of healthcare settings, N95s are rare and often worn incorrectly so a second mask over the first is actually providing moderately more filtration and protection.
Everyone should be wearing properly fit and sealed N95 masks from well known brands like 3M. Pieces of cloth that vaguely cover the mouth and nose but leave giant gaps do not protect the user very well. A proper 3M N95 that intentionally worn un-fit, with large gaps along the nose and sides becomes an ~N40.
Unfit masks of any type, and fit "KN95" masks that have such a high pressure drop all air goes around the edges (they suck in and out) barely protect the user of the mask at all. Yes, they're better than nothing. Much like wearing sandals in a blizzard is better than being barefoot. But it won't stop your toes from freezing off and unfit, unrated masks won't protect you from aerosol infection.
The solution of two masks hardly helps if there are still large open apertures along the sides. The only real solution (within the USA) is to use the defense production act to force 3M and Ameritech to fully hire-up and run their factories full time, as well as building new electrospun N95 mask factories. Every single person in the USA (and canada, and elsewhere) should have enough N95 masks to use a new one each day. That is the only solution to the mask problem. Double masking with bad masks is just more security theater.
It's been an entire year. The excuse the real masks are only for hospital personel is no longer valid. The people deserve, they need, real masks.
My guess is that in order to increase the number of people wearing masks, they're trying a new scare tactic: maybe you should wear 2 or 3 masks. Maybe they hope that will cause people to wear at least one.
Gotta herd the cattle somehow, I guess.
To respond to your specific statement, part of the problem is that "don't work" is too blunt and not quite true. "Don't protect the wearer" might be true. "Barely protect the wearer" would be. "Don't provide strong protection for others" also true. But even a poorly fitted cloth mask is almost certainly better than nothing. (Of course, I'd also believe that they likely provide a false sense of security, leading to risk-taking that more than offsets their benefits.)
This ties in with one of my biggest frustrations of the whole pandemic, at least individual behavior: so many people's risk analysis is just sorting things into "safe" and "unsafe", rather than thinking in degrees. "Cloth masks don't work" is unhelpfuly binary and non-specific. (Though including "poorly fitting" makes it better -- "ensure proper fit" is actionable advice.)
And while efficacy of "cloth mask" vs. N95 is good to know, "cloth mask" is a super-broad category. I'll occasionally see people specify "single layer cloth masks", but the only single-layer cloth masks are gaiters, and even those are frequently folded over double.
How good is my 2- or 3-layer cloth mask? What materials should I use? (To be fair, I have seen some people answer this question.) Is it relevant that I can barely feel my breath through it or around the edges even if I blow hard? How much of a difference does fit make?
Ideally we'd all have and use good quality N95s, but we shouldn't make perfect the enemy of the good. We need information that will help us do better, rather than a binary "N95 good; everything else bad."
What I am saying is that KN95 types in the USA are of such variably quality they are not a good choice. Use local standards and brands.
Throwing them away after 1 use would be silly. I personally have enough masks, and few enough indoors engagements, to let my N95 sit for a full month between re-uses.
And besides if you're arguing that we need to reduce landfill you shouldn't be advocating for any sort of anti-virus measures as any sort of population reduction will do more to reduce landfill than any sort of reusable mask could ever hope to accomplish.
We already have more deaths from COVID than ww2 yet...crickets on the mask production front. I’m guessing it is because in a year when COVID is not a thing anymore it will not be profitable to have that much capacity and corporations do not want to ramp up that much.
Also making masks is probably not the best strategy. If we used reusable p100 filters that would be much more effective even for the general public. I used to work with fiberglass wearing a similar respirator with an organic vapor cartridge and it was usable for hours at a time, so no idea why we haven’t started using these in high risk [grocery/prisions/schools] instead of KN-95/N-95 of which there is a counterfeit mask problem.
https://www.trendhunter.com/trends/scandinavian-walking-helm...
Let's do the math for surgical masks which are like n20. Adding two n20's gives you a n40, which is marginally better than the n95 double masks.
Let me vent by saying I was on the pro-mask side when the CDC and WHO were against them, I made a website that went viral and got 7 million view letting people know your government officials were wrong. I had my account banned from Reddit and Facebook over being pro-mask. I even got contacted by the CDC to think about taking down the site. I told them to fuck off. When this pandemic is over and we can do a post-mortem on the pandemic the CDC and WHO will have blood on their hands for the poor messaging around masks.
I for one have been double masking n95's for a while.
I agree with you a 100%.
It was such a common sense thing. I was telling my friends back in Feb/March that they should make it mandatory.
Sometimes experts get it wrong and it costs millions of lives. So sad..
Usually people use sub par (cloth, surgical), badly fitted (loose rubber bands, misfitting nasal) masks or wear them wrong - the classic being a mask not covering the nose.
The rating percentage is for specific test setup. For biological aerosols, the result is quite different in that small particles are stopped by diffusion, and the filter rates tend to be better than rated for masks, as long as leakage is low.
Now, the situation is different with weak filtering materials such as used in surgical or cloth masks, but the result is not additive either.
Have you actually tested that the specific double N95 configuration even provides single N95 protection? (Esp. leakage) No? Then better not mess with the design.
Your advice is going to kill people.
> I for one have been double masking n95's for a while.
1) You don't have the equipment to check that those are actually N95s that meet the spec
2) You don't have the equipment to do a correct fit-test
3) Modifying safety critical equipment is dangerous. You haven't doubled the safety, you've made these masks less safe.
I'm pretty sure you're not wearing the masks tight enough. Here are example photos from people who spend a day in PPE:
https://twitter.com/LondonNurse2015/status/12472750559874252...
https://twitter.com/jbon93/status/1247626644208189444
https://twitter.com/RochesterKaren/status/124644595651562700...
https://twitter.com/gabbyjackson95x/status/12479391789623255...
https://m.youtube.com/watch?v=5XdeMD7YueY
The N95 protects you, but many N95 masks have exhalation valves that blast particles away and make it easier for you to breath.
The cloth mask on top of the N95 protects others, by reduce the amount and distance of particles. This is especially true for N95 masks that have valves.
Not like this: https://twitter.com/jane_whitelaw/status/1334653360683839488...
Or like this: https://twitter.com/jimmyhawk9/status/1354240965498654720/ph...