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There have been a number of do-it-yourself (DIY) mask designs released and tested by both universities and other institutions on account of world wide Personal Protection Equipment (PPE) shortages. Some were designed at the time of the SARS epidemic, and use double-folded kitchen paper towels with tissue.

Even though double tea towel masks are more effective in reducing viral exposure, it's difficult to breathe with it on.

What design has been tested to provide relatively good protection while being comfortable to wear and breathe while wearing them? And it needs to use readily available materials throughout the world.

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    Why is this being downvoted? There is a huge shortage in masks in many parts of the world. If this question is off-topic please direct us to the correct place to ask this.
    – Teimpz
    Mar 19, 2020 at 19:21
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    I suspect that the downvotes are from people who haven't seen the meta discussion in which we agreed we would temporarily relax the prior research rule on questions and answers regarding this pandemic.
    – Carey Gregory
    Mar 21, 2020 at 1:12
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    We don‘t wear masks to protect ourselves but to protect others, doctors and nurses protect patients. The reason that people in Japan and China are wearing Masks is to filter particles of air pollution. Mar 21, 2020 at 4:35
  • I assume there have been down votes because the question suggests that masks protect from infections. Women are making coronavirus face masks out of their bras, but experts warn masks won’t necessarily stop you from catching the virus... insider.com/women-making- coronavirus-face-masks-out-of-their-bras-2020-3 We don‘t wear masks to protect ourselves but to protect others, doctors and nurses protect patients. The reason that people in Japan and China are wearing Masks is to filter particles of air pollution. Mar 21, 2020 at 6:34

5 Answers 5

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DIY Designs - most do not carry efficacy data claims

Note that many of these are only respiratory protection designs. You also need to protect your eyes in a high risk situation eg. looking after an infected relative. Get protective goggles or your own glasses and attach a plastic shield eg. plastic pamphlet holder to the glasses for a full face shield.

Combined mask with face shield

University of Hong Kong-Shenzen Paper Towel Mask

  • Claims 90% filter protection of a surgical mask

https://www.youtube.com/watch?v=aNjpH5lBZ8w

Masks only

Freesewing sew your own mask from cotton T-shirt etc

A4 PDF Pattern

CDC letter - simple mask (uses heavyweight T shirt material)

CDC

Instructables Cloth Masks patterns

  • as with all cloth based, wash in hot water to pre-shrink

Instructables

Copper 3D design using PLA 3-D printer

  • seems to need their special filter but perhaps use HEPA material?

3d printed masks unsafe poor fit or build up of CO2

Instructions

Face shield only

Field Respirators

First industrialized field 3D printed emergency respiration device to support hospitals and ICUs.

Door Handle Opener

More Reading

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

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  • Also remember, masks, even for N95 masks, to be effective, they need to be fitted properly.
    – paulj
    Mar 25, 2020 at 14:49
  • Normally you have what is called a "Fit" test to see if your face can seal against a mask. Mar 26, 2020 at 4:03
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Here is a relevant link on the best materials to use in creating a handmade face mask:

https://www.cambridge.org/core/journals/disaster-medicine-and-public-health-preparedness/article/testing-the-efficacy-of-homemade-masks-would-they-protect-in-an-influenza-pandemic/0921A05A69A9419C862FA2F35F819D55

Also, here is relevant study on the effectiveness of a saline solution applied to a face mask that can kill flu-like viruses (through the osmotic effect) even within five minutes:

https://www.thestar.com/news/canada/2020/02/11/salt-is-the-secret-ingredient-in-these-face-masks-that-could-prevent-spread-of-next-coronavirus.html

https://www.nature.com/articles/srep39956

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There is literature to support that wearing a mask decreases transmission of infection ([Leung, N.H.L., Chu, D.K.W., Shiu, E.Y.C. et al. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med 26, 676–680 (2020).1), however, there is exceedingly limited evidence that wearing an improvised mask is anywhere near as effective as standard protective equipment (N95 respirator or better).

However, with that said, although I wear a powered air purifying respirator at work (and my company owns the equipment specifically for my personal use, so I could in theory use it elsewhere), I use a homemade cotton mask when outside of home for routine tasks (shopping, getting the vehicle fixed, etc.).

As others have said, wearing a mask is for protection of others from droplets that you might generate, and as such these masks function similar to how the surgical mask was designed (to protect the patient from the surgeon, not vice versa). If everyone was to wear a mask, this could be compared to the concept of "herd immunity" where people are protecting each other. It is a bigger concept than purely personal protection, which an improvised mask fails at any way you wish to look at it.

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  • How much the cotton mask protects others? Jun 4, 2020 at 16:05
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    @América There is not a definite answer to that question at this moment. In conjunction with handwashing and social distancing, the combination seems very effective. As a single intervention, there is no high-quality data to quantify the protection. Older studies on influenza had quoted a number needed to treat of 6 (six people needed to wear a mask to prevent one infection). We do not have coronavirus-specific newer data.
    – RudyB
    Jun 13, 2020 at 20:23
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In a scenario of being forced to choose from DIY designs (yikes!): Perhaps understanding: How are masks tested for efficacy? would provide insight into comparing DIY mask designs.

Efficacy Test example: https://www.astm.org/Standards/F2101.htm

Possible Mask features that drive efficacy:

  • physical design: does the design effectively position the filter?
  • filter material & design: Which materials will work better than others?
  • comfort: Will users be able to wear these for extended periods without discomfort?
0

From {1}:

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References:

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    Downvoted for information as image with no information in text extrapolating and explaining the results to 1) those who cannot see the image, and 2) those who may not understand the information in the image. This is tantamount to a link only answer. Mar 27, 2020 at 8:13
  • @ChrisRogers you want me to convert a histogram into some text? lol Mar 27, 2020 at 8:59
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    Well, that could be a start for reasons mentioned in the meta post linked. You could list each homemade mask material mentioned with their effectiveness in % for the 2 tests. Plus, for those who don't know, a brief explanation maybe useful on what the significance is between the virus and bacteria mentioned and the fact that we are trying to block the virus which causes COVID-19. Mar 27, 2020 at 9:43
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    What exactly do these numbers tell us? Which of them are "good enough" and which aren't?
    – Philipp
    Mar 27, 2020 at 10:08
  • @Philipp Good enough depends simply on your acceptance threshold. Mar 27, 2020 at 10:10

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