Download the instructions here (PDF).
Be creative! Use what you have at home! The materials specified are purposefully vague, you won't find any Amazon links because if we all tried to use the same thing, we'd all just run out faster.
Use anything. Old bedsheets, pillowcases, dish towels, napkins. Literal rags. No need to go out any buy anything new, that would miss the point. Flannel is super cozy. High thread count stuff actually has pretty decent filtration ability even without a "real" filter layer.
More info forthcoming. For now check out https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/ for a good overview of existing data. We've been using air conditioning filters (1 or 2 layers of MERV-13 and MERV-14 filters, no fiberglass!). Anything is better than nothing, so even if you leave this out, the mask will help. (But don't let it give you a false sense of security).
14 gauge copper wire works great, stiff but flexible enough to conform to the nose. (12 gauge will do in a pinch, but it's really stiff). Doubling up 18 gauge also works. If you don't have wire, be creative! You can also try:
Here's an unedited collection of random bits of info, updated very intermittently.
...Rigorous testing, known as particulate filtration, to evaluate 13 different designs from approximately 400 masks made by community volunteers...
The best homemade masks achieved 79% filtration as compared to surgical masks (62% to 65%) and N95 masks (97%). But other homemade masks tested performed significantly worse, sometimes demonstrating as little as 1% filtration, Segal said.
The best-performing design was constructed of two layers of high-quality, heavyweight “quilter’s cotton” with a thread count of 180 or more, and those with especially tight weave and thicker thread such as batiks. A double-layer mask with a simple cotton outer layer and an inner layer of flannel also performed well, he said.
Covid-19 moves like a silent assassin, with unwitting accomplices. Maybe you’ll be one of them. The best way to ensure that you’re not: wear a mask, and keep your distance from others.
...the virus is primarily transmitted through tiny droplets of saliva ejected when we speak. You can’t see them, but they are there. We also know that these droplets can go significantly further than the 6ft which is widely cited as a safe distance
...placing a layer of cloth in front of a person’s face stops 99% of the droplets
Prof David Heymann CBE, a World Health Organization (WHO) adviser, said, “I think that wearing a mask is equally effective or more effective than distancing.”
In a paper published in Nature on Friday, a five-year study from the University of Hong Kong and the University of Maryland has found that a simple non-fitted mask blocked 100% of coronavirus droplets and aerosol.
Every country with enforced mask usage shows dramatically lower death rates compared with countries not using masks widely.
Modeling by Yale researchers estimates that “the benefits of each additional cloth mask worn by the public are conservatively in the $3,000-$6,000 range due to their impact in slowing the spread of the virus”. A cloth mask is basically free, since you can make one from old T-shirts or sheets. So the economic payoff is hard to question. What other investment pays off by over 1,000 to 1?
“Masks for All laws” are now in place in Israel, Austria, the Czech Republic, Hong Kong, Mongolia and elsewhere, with more locations added every day.
If we can’t rely on our governments to take this step, then we will have to take things into our own hands. We must rely on grassroots community efforts to get up to that magic 80% compliance number. We know this is possible, because the Czech Republic did it last month.
Out of curiosity, we tested non-medical materials for filtration. A scarf is NOT helpful for filtering aerosols, which may carry coronavirus. Instead, what about furnace filter/pillowcase? Thanks, @linseymarr for the filtration test doc! @MissouriSandT @JGB_Burken @aaqrl_wustl https://t.co/nm4j1WA3ct pic.twitter.com/5RkzYdYdnt
— Yang Wang (@carlwangyang) April 3, 2020
Oooh, handy for those of us who can't sew or don't have a machine! Mask-making with a handkerchief & hair ties: https://t.co/xnp30VzmpQ
— N. K. Jemisin (@nkjemisin) March 31, 2020