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Masks Can’t Work–But Not for the Reasons You Think

I’ve been pondering this issue since last fall, waffling constantly about whether I should write about it at all. I was sure that any number of other people would make the point I’m about to make, but I haven’t seen it. Maybe it’s too simple. Maybe people are past caring. I don’t know.

Here’s my point: Consumer-grade masks can’t stop SARS-CoV-2. It’s impossible. But not for the reasons you might think.

First, some background. Surgical masks were originally developed to protect vulnerable patients from pathogens exhaled by doctors. They were not designed to protect healthcare workers from patients. Some people recognized this early on, in memes stating (rather too confidently) “My mask protects you. Your mask protects me.” In a perfect world, that might be true. Such a world does not and cannot exist.

The key word here is perfect.

In order to be effective, a mask must meet these requirements:

  1. It must be made of a material allowing the flow of air while seriously restricting the flow of droplets and aerosol virus particles. Such masks are uncommon. The only ones I know of are N95 masks, without exhalation ports. (Exhalation ports render an N95 mask pretty much worthless, as this study showed.) And I’d just as soon reserve N95 masks for front-line healthcare workers.
  2. A mask must fit close to perfectly. I don’t know how anybody expects one mask design to fit all the infinite varieties of human faces. Fit often requires that the mask straps be very tight, so tight as to be nasty uncomfortable. A couple of loose straps over your ears won’t do it, especially if your face is unusually long or wide.
  3. The mask must be worn perfectly. If adjusted for comfort, even a perfectly fitted mask will leak like a sieve and ceases to be effective.
  4. Touching the filtering medium of your mask is a no-no. If you’re in an area with aerosol virus particles floating around, those particles will accumulate on the outside of the mask. Touching them transfers them to your fingers, which can then easily transfer them to food or tissues.

The primary failure mode for masks is leakage. When the whole mask fetish first became a thing, we bought some masks and I did some experimenting. I put a mask on as best I could, dipped a finger in a glass of water, and held the wet finger around the edges of the mask while I breathed normally. I could easily sense jets of air at several places around the edge of the mask, no matter how I adjusted it. These jets did not pass through the mask material, and if the wearer is contagious, the aerosol virus particles will be sent in several directions with significant force. I was surprised, in fact, at how much force was behind the jets from even normal breathing.

Think about jets of air for a moment. Even a tiny amount of air will move quickly if forced through a small hole or gap. Those jets leaking around the edges of your mask will carry aerosol viruses a long way. Sure, droplets quickly fall to the ground within the standard distance of six feet. SARS-CoV-2 travels as both droplets and as aerosols. Droplets are big enough to be trapped by the mask’s filtration medium. Aerosols are so small that most go right through it, absent expensive materials like those used in N95 masks. Cloth masks depend on the nature of the cloth. Cheap surgical masks barely stop them at all. Woodworking masks are completely worthless. Hold that thought; I’ll come back to it.

I’ve found some interesting videos. In this first one, a woman takes a hit off her vapestick, puts her mask back down, and then exhales. She immediately blows two jets of smoke right into her eyes, and then starts choking. Bad idea. The takeaway is that smoke came out the edges of her mask in a hurry. Obviously the mask was not being worn correctly. Hold that thought too; I’ll come back to it.

Here’s another, better video, in which a man wearing several types of masks inhales from a vapestick and exhales while wearing the masks. (I can’t tell whether he’s wearing the masks correctly or not, though it looks correct to me.) Smoke or vapor (I’m not especially familiar with the technology) streams out from the edges of the mask on every side. The smoke or vapor is there there simply to help you visualize how leaky cheap masks are. Clearly, my mask doesn’t protect you, and your mask doesn’t protect me. (The video was originally posted on YouTube several times, and taken down every time. It’s now on BitChute. The Powers obviously don’t want you to see failure modes in enforced conventional wisdom.)

Even a high-quality mask will leak around the edges, especially if you have a nonstandard face. We needn’t mention gaiters, which have no mechanism for preventing significant jets through the gaps on either side of your nose.

Now, I told you all that to tell you all this: Suppose a high-quality, perfectly fitting mask worn perfectly traps a significant number of aerosol particles. Here’s the extra-large economy-sized question:

How do you guarantee that all mask wearers are wearing effective masks that fit well and are worn correctly?

We all know the answer: You don’t. Masking is a collective exercise. It’s gotta be almost everybody or it might as well be nobody. There is no enforcement mechanism that will render a mask-wearing public immune to SARS-CoV-2. I’m pretty sure there’s no enforcement mechanism that will keep a mask-wearing public from exhaling massive numbers of aerosol viruses. Post mask cops on streetcorners, checking mask types and adjusting them to fit correctly and well? Really? Most of the public doesn’t like masking and will do the minimum necessary to meet a mask mandate. I’m thinking a lot of them will wear their masks as loosely as possible, just for spite.

My conclusion is this:

Enforcing an effective mask mandate on the public is impossible.

I can already hear the crowd screaming at me: “The perfect is the enemy of the good!” Well, yes. In this case, the chain of contingencies leading to effectiveness is so long that anything less than perfect is just about no good at all.

“But if a mask stops even one virus…”

The fifty billion other viruses gleefully jetting away around the edges of your mask might want a word with you. Or maybe they’ll just laugh.

Note well: This is a controversial topic, and as with all such topics, I require heroic courtesy from all commenters. Screaming at me won’t convince me of anything; it just makes you look like a moron. I’d appreciate that if you take issue with something I’ve said, take issue with the point I actually made.


  1. Mapleton Reader says:

    You may be interested in a review of a 115 scientific papers on masks ( published a year ago. My summary of their summary is
    1. In the first few months of the pandemic, there was conflicting mask guidance was given by several official sources.
    2. From multiple controlled experiments and field observations (as of 2020) wearing masks ‘reduces’ the transmission of COVID-19 for healthcare workers and the public. Most of this evidence was COVID-19 specific. It is uncertain that mask wearing protects the wearer.
    3. Cloth masks can stop 90% or more of the dispersal of droplets carrying the virus.
    4. Masks are highly safe, with only minor and uncommon side effects. However, some individuals should not wear masks (see paper for exceptions). They are also quite cost effective.
    5. There is universal agreement that masking alone will not be enough to stop the pandemic. Social distancing, testing, handwashing, contact tracing (and my addition to his list, vaccination) all help.

    To your point, I agree that masking is not 100% effective, but apparently it is not 0% effective either (as you imply in your last argument which I assume was meant as hyperbole but to me invoked a ‘straw man’ logical fallacy). According to the research (admittedly a year old) mask wearing can slow the spread of Covid, even if the mask is not 100% effective.

    1. I might have been clearer in what I was describing: A sort of network effect for mask effectiveness. Within a population of a given size with intermittent proximity, there will be people who wear masks perfectly, more who wear masks imperfectly, and a certain number who do not wear masks at all. Even those who wear a good mask about as well as it can be worn will inhale some aerosols. (N95 mask use among the general public is very rare.) Those who wear bad masks or masks badly will inhale more aerosols. People who don’t wear masks at all will inhale lots of aerosols.

      It’s worse for exhalation, as the videos I linked to demonstrate. All masks leak at the edges, except possibly N95 masks worn correctly, again being so rare as to be ignored. I certainly agree that most masks filter out droplets reasonably well, but droplets are really not the problem.

      My reasoning goes like this: Over a period of time, a masked population with masks of various qualities and effectiveness will pass one another, sit next to one another (think public transport) and in consequence breathe other people’s exhaled air, which includes unfiltered air that leaks out of masks at the edges. Even people who wear good masks will not always wear them perfectly, and over a period of time their chances of encountering enough viral particles to be infected rises. People wearing bad masks will be infected sooner, and people deliberately trying to meet a mandate while having a mask barely hanging on at the tips of their noses (I saw this a lot in the mask era) will be infected early on.

      In short, people with masks of varying effectiveness (say, from 0 to maybe 60%) mix, and across time even the most careful maskers will become infected. (Even careful people mess up when they’re distracted or in a hurry.) The only way to raise the effectiveness of the masks of an entire population is to enforce mask quality and fit across that entire population, and I’m pretty sure this is impossible. Individual masks may work well. Masks in the aggregate do not. Jets of viral particles are real, and ubiquitous. (A study I cite below makes that point very clearly.)

      Most masks block droplets well, and aerosols badly. I’ve tried to find good numbers of what percentage of aerosols get through various kinds of masks made of various materials. Research is sparse. The paper cited below, from BMJ, has nothing good to say about cloth masks:

      Although the paper is well worth reading, here’s the money quote: “Penetration of cloth masks by particles was almost 97% and medical masks 44%.”

      The best study I’ve seen so far is from Cornell and can be downloaded as a PDF:

      They have a better opinion of masks than the BMJ paper. On the flipside, they’re the only study I’ve seen that looks closely at mask leakage in the form of jets. That study is the main reason I emphasize mask leakage as much as I do in my reasoning.

      So how well do masks work in the aggregate? Greater than zero, sure. Your point. How much greater is an unanswered question, because I have yet to see the question even asked. I will point out that masks have been sold to the public by governments as very strong protection, with little or nothing said about how they are to be worn or what their limitations may be. A bunch of masked people in a sports bar screaming at the umpires on TV will be all jets, and after a few hours of that, I doubt masks do any good at all.

      I’ve mostly come to the conclusion that we cannot stop the spread of SARS-CoV-2 by dubious and damaging things like masks and lockdowns, and should focus on viral preventives like quercetin taken with zinc, and vitamin D supplementation. Ivermectin works against SARS (the studies are out there) but if you say that on Twitter or Facebook, you’ll get banned. There are other issues (especially PCR testing and natural immunity) but that’s a whole ‘nother entry (or fifty) all by themselves.

  2. Oleg Panczenko says:

    You may find this paper of some interest:

    Abhiteja Konda et al. “Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks” (

    From the Abstract: “Our studies also imply that gaps (as caused by an improper fit of the mask) can result in over a 60% decrease in the filtration efficiency, implying the need for future cloth mask design studies to take into account issues of “fit” and leakage, while allowing the exhaled air to vent efficiently.”

    There is a correction at which does not invalidate the conclusion above.

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