I tried this using a bandana. I think I need different hair ties because the ones I use are super tight. While it worked, my husband started giggling because my ears looked like they were gonna rip off of my head…or so he says.
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Apparently the Ninja Hoodie is a thing:
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I agree.
Unfortunately she heard somewhere that it was bad to re-use masks so she threw it away when she got home from the airport. By the time I found out, the trash had been picked up. So now she is back to no mask. 
I get that re-using masks is not preferred when you have an unlimited supply but no mask is definitely a downgrade.
Interesting anecdote. When she exited immigration at the Cebu airport security was there and escorted her to an ambulance that drove her home. They were doing this so that people flying into the country did not interact with the taxi drivers. She is in quarantine for a month and health care workers visit her every morning and evening to check on her status in person.
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I compared it to various birth control methods. Condoms, even when used correctly, are not 100% effective, nor are birth control pills, or diaphragms. However using these three together can significantly decrease your odds of getting pregnant. Similarly, a 50% effective mask (approximate rating for a t-shirt, according to some rankings) seems pretty useless, and it is … if that’s all you’re using!
Wear a DIY mask, maintain social distances, and wash your damned hands.
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I reluctantly too some insurance photo gigs because we need the money, so I scrounged around the house for that mask that I absolutely knew was here because I saw it when we moved two years ago. (Easy, right? Should be right over … um …?) Found it this morning and not only was it in a seal package, it turned out to be an N95. It felt like finding a unicorn in your backyard.
Yes, I read the directions and used it correctly. Unfortunately, although it had been in a seal package, the elastic on the bottom strap did not age well and it broke as I was putting it back on for the second gig. Luckily, only the first gig was with someone that I’m sure wasn’t taking things as seriously, so felt alright about that.
Still time to make some masks, I think.
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Funny that you phrased it that way because I finished sewing a stuffed unicorn for my daughter today just before starting on sewing a batch of these masks.
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If you can’t find the unicorn, you have to make your own, of course! I’m considering going with a steampunk styling with mine, but it’s going to depend on what we have in the boxes labeled “crafting materials, fabric.”
Doh! I also noticed a typo in that quote from me. Should have been “sealed,” of course, but I kind of like it that way.
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Is there a mask style that’s still effective for people with facial hair, or a style of facial hair that’s ok with these masks? My kids are begging me not to shave my beard but I’m pretty sure that’s necessary for most of the masks to be reasonably effective.
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I think it would depend on the specific mask / beard pairing. One of our camp medics posted that he did have to shave his beard for his EMT job, as it wouldn’t let their N95 masks seal properly. I think even with a purely cloth mask, a fuller beard is going to reduce efficiency some, unfortunately, but I have no data on how much.
I know I want my boyfriend to keep his beard, but it’ll grow back if he does, whereas he won’t if he gets sick. Luckily he was already on a WFH option, but it could be important if he does need a mask. (He had a quadruple bypass a few years back, so is very much in the higher risk category. Then again, so’s most of my polycule. Yay.)
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That’s not bad at all. The folding adds layers of fabric which adds to the effectiveness as well.
I think a little more clarity & discussion is needed here. Sorry so long, but there’s a lot to cover. I can provide links to a lot of this stuff, but I am tired and want to go to bed soon, so I’m not linking all these points.
As mentioned above, the virus itself, were it aerosolized, would go through all available face masks & face respirators (a surgical mask is a mask, an N95 is technically a respirator, as referred to by CDC and WHO and often Niosh, but most people call them all masks ,and so that’s easier). The COVID19 virus rides around on droplets when we cough, sneeze, breathe, and the droplets are bigger than 0.3 microns, which is why masks can work. In that, we are lucky.
But - masks are not perfect, and they only work if they FIT. That’s why hospital staff have to get Fit tested every year - to know which mask actually works, and which size of which mask. If they don’t fit right, air comes around the mask instead of through the mask.
There are various levels of filtering. Look up the MERV chart before you grab “HEPA” vacuum bags, and look at actual HEPA filters. They are not thin and easy to use, and what you think are HEPA filters that fit into a surgical style mask are probably not. Most medical grade HEPA filters are part of PAPRs - they use a blower to pull air through the filter, bc HEPA filters can be too difficult to breathe through.
MERV filter ratings are commonly applied to things like furnace filters. MERV 16 is about equivalent to N90. Pretty good. But no one has actually tested a furnace or vacuum filter to see if it really Does work out to N90.
N ratings & such -
NIOSH rates filtration by the percentage of 0.3 micron particles that the mask stops. So N100 stops them all, N95 stops 95%.
N means Not oil proof
P means oil Proof (great for paint!)
R means oil resistant
Surgical masks are actually close to the filtration rates of N95 (if not the same, if you believe Halyards claims (no reason to doubt them)). It is the fit of a surgical mask that is inferior, plus some of the coatings that cause the surgical mask to perform less well.
Home made masks, without actual filter material (ie, cut from cloth) are probably closer to N50, maybe less, definately less if they are wet (from breathing hard, from rain, from washing it…).
Someone at UFL recently showed that blue surgical wrap (halyard h600 is what they tested) that is used to wrap up surgical instruments before they get sterilized, is N95+ when double layered. They are making masks out of it, bc it is cheap and plentiful and you can sew it and you can sterilize it. Other hospitals around the US appear to be doing the same. (Note that the UFLorida people are trying to patent their masks - bc profit matters more than saving lives all over the world. see link at bottom of this post for their webpage, with directions to make your own mask)
The protective bonus of wearing a mask (outside of healthcare) is basically that you aren’t spreading the virus from yourself to others. That’s why everyone should be wearing some sort of mask - we could be infective and asymptomatic, so the maks will help keep us from spreading the disease. They also provide some protection, so that’s awesome. But if you wear a mask, and it has virus on it, and you take it off wrong and rub your eye… There’s a reason we practice using PPE at work. It’s hard to be just right.
In regard to @yancy_espinoza comment - no, a mask is better than no mask. Provably. What you have to do when wearing a mask is to continue to social distance as if you had No Mask. Then you are getting the benefit of both the bahvior and the mask. But that’s hard to do for @anon29537550 or for an ICU RN.
Summary:
Bad PPE is better than no PPE.
A cotton mask is better than no mask (especially to protect others).
A surgical mask is better than a cotton mask.
An N95 is better than a surgical mask.
A PAPR with a HEPA or N100 is the best, but not often reasonable
Facial hair is BAD for mask fit.
Wearing a mask makes people realize when they touch their face, and can help you not touch your face when the mask is on - which just might slow the spread.
We should all start wearing masks to the grocery store. Watch for the CDC to belatedly recommend that. Keep washing your hands when you get home.
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I made four masks from the rag-mask pattern this evening, after fixing my long-disused sewing machine. The pattern is easy to sew and the seal around the face is surprisingly good. Much better than I thought it would be.
I used an old T-shirt for the outer cotton part. For the inner filter material, I used a piece of X90 Wypall disposable shop towel. It’s non-woven and extremely durable – will definitely stand up to washing. I might try two layers of filter for my next couple and see how the breathability feels.
I highly recommend this pattern.
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Thanks for the feedback!
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Or motorcycle helmets.
Out of curiosity, since you seem like one who might know: at .3 microns(especially in fairly modest airflow/pressure situations) one is getting down to the scale where filtration can no longer be treated as neatly analogous to idealized billiard balls passing, or not, through idealized wire mesh of various sizes; and one has to worry about charges attracting and repelling and adsorption and surface tension and suchlike witchcrafty stuff that they don’t cover in 101-level approximations class.
Are there mask materials(or materials that seem like they should be great mask materials but pointedly aren’t because of these problems) that exhibit drastic and unintuitive changes in effectiveness one way or the other in response to environmental factors like humidity; or ones whose effectiveness degrades over time in a particularly nonlinear way?
Also out of curiosity, are there any even approximately mask-scale systems that have active components(beyond pumps to assist with filters that have lousy flow rates or to provide positive pressure) to exploit these properties: keeping the mask material either like-charged with respect to the expected contaminants so that they get attracted and absorbed by the filter; or opposite-charged to repel particles that are, mechanically, small enough to sneak through?
I’m assuming that, in broad strokes, anything sold, reasonably honestly, as a protective mask gets less effective with use; probably isn’t quite what it once was(though potentially better than loaded-with-virus) after a wash or sterilization attempt; etc. but I can imagine that there might be less than totally intuitive(and, unless you have test gear that most of us don’t, hard to empirically verify): I’d suspect that a material used for facial masks is optimized to work when comparatively damp(since ■■■■■ is the word we cannot say), since anything the user breaths through is effectively in a high humidity environment, while a furnace/air duct filter might be fantastic at dealing with a fairly high flow rate of hot air; but potentially designed on the assumption that it will remain nice and dry.
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As I am a pediatrician, that is a kinda huge issue for me, even with the much-less-apocalyptic masks we are currently using!
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Any mask/respirator degrades functionally with humidity. Much of the function is not so much x nm ball and <x nm hole, but electrostatic attraction (as you mentioned) which stops working with increasing humidity. Also they just get harder and harder to breath through as breath condensation occurs inside the filter material. In my experience, that is a much more limiting factor than plugging from external sources. In fairness, I have never tried to use one in a very dusty environment, so takes that for what it is worth. As @fiatrn points out, how you handle the mask plays a huge part in the protection as well. You have to treat the outside of the mask as if it is coated in virus, which is where the reuse becomes a real issue.
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(Artist’s dramatization of PPE-induced pediatric relations setback)
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Yup, that’s about right!
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