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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsDuke U study: Neck Fleece Masks Are Worse Than No Masks
Folded bandanas and knitted masks also performed poorly and did not offer much protection.
"We were extremely surprised to find that the number of particles measured with the fleece actually exceeded the number of particles measured without wearing any mask," Fischer said. "We want to emphasize that we really encourage people to wear masks, but we want them to wear masks that actually work."
https://www.cnn.com/2020/08/08/us/duke-university-face-mask-test-trnd/index.html
underpants
(182,271 posts)I stopped wearing mine after the first time I wore it.
Didnt make sense that it could work very well.
Mike 03
(16,616 posts)that theirs are used by Serena Williams and Dwyane Wade. Some of you might have heard the ads. I don't recall if they specifically make the claim they prevent COVID-19, but I feel that is the strong implication of the ad. Also, this is a company I've never heard ads from prior to the COVID-19 pandemic.
nuxvomica
(12,360 posts)I saw one yesterday with an ear to whether they mention viral or bacterial protection and they didn't.
LisaL
(44,962 posts)Even N95s only block 95% of particles (thus N95), so they are not going to be 100 % effective. And that 95% depends on a perfect fit with no leaks.
mucifer
(23,371 posts)If I'm in a place with strangers, I add the
face shield over my mask and eyes.
2naSalit
(86,039 posts)concluded they were only half implying that you could use them as virus protection. But if you think out what they are highlighting as features, the cooling aspect, is anything but protective. They claim that the fabric is "moisture activated" for cooling purposes. Anything that increases droplets is just the wrong thing. I figured out the neck ring thing is not an option for protection.
nuxvomica
(12,360 posts)The guy spends every moment he can duck-hunting or fishing and has plenty of these things, and wears them when he's out among people for COVID protection. He's also very liberal but rarely goes online and might not be aware of this study. He's the type that when I tell him this will probably rush out to get some N95s. Thanks for posting.
LisaL
(44,962 posts)Even cotton masked worked, per the study. As far as I can tell the study focused on spread from the wearer. So N95 work best in preventing the spread as well as protecting the wearer (which we know from other studies)). But surgical masks also prevented spread pretty well, and cotton masks surprisingly did well too (not as well as N95s, but still...)
mucifer
(23,371 posts)LisaL
(44,962 posts)I think the key here to fit close to the face with no leaks. And material that is not knitted.
sl8
(13,584 posts)This is the best no-sew bandana mask design that I've tried so far:
Seems to seal very well. I think the fit around/under the chin is actually better than the disposable 3M N95s I use. Overall, you end up with 4 layers of bandana cotton fabric + 1 layer of filter element. Also, the elastic straps go around the back/crown of head, rather than around the ears.
LisaL
(44,962 posts)sl8
(13,584 posts)The "cowboy-style" bandana has 2 layers, no filter element, no elastic, no formable nose strip, is completely open along the bottom, and forms a poor seal across the top.
About the only similarity between the the one in the Duke study and the one in my post is that they both incorporate a bandana.
crickets
(25,896 posts)I can save it to wear when bike riding in winter after this is all over I guess. I am glad to hear how well the basic paper masks work, as well the cotton homemade. I have both, but the cotton is so hot I've relied on paper recently and hoped for the best. Good to know!
I do need to send this to a family member who has been relying on bandanas - maybe she'll finally spring for something safer.
Thanks, mucifer!
LisaL
(44,962 posts)I don't think there were any tests done on valved N95 masks before declaring them useless for protecting others because exhaled air is not filtered. This study suggests at least some of the valved masks might be o'key.
Ms. Toad
(33,915 posts)If something is snug against your face and you are breathing directly into it, the force of your breath will expel the droplets through the covering, and when there is resistance, it will break the droplets into the size necessary to fit through the holes in the covering.
mucifer
(23,371 posts)I wear the disposable procedure masks you can buy stores when I don't work.
Ms. Toad
(33,915 posts)in the mask or filtration device).
If you think about sending used cat litter through a sieve - as long as the sieve holes are bigger than the kitty litter components, the sieve will break up the clumps and send them through the holds.
When you get to an N95 sieve, the holes are too small for the basic kitty litter to go through.
That's the basic principle.
Now use a mask that has holes large enough for the virus to pass through. If you are using a mask that porous right next to your mouth when you cough, speak, etc, the sieve (mask) will break up the droplets that are too large into smaller droplets that still fit through - and aerosolize them.
Your N95 mask has holes too small to let even aerosolized droplets through - so it doesn't matter how close it is to the point of expulsion from the body - they ain't gonna get thorugh.
Buckeye_Democrat
(14,846 posts)Good video about the physics of N95 masks:
Thanks for posting the video. I think a lot of people are thinking of the meltblown fiber of the mask as having "holes" which are smaller than the virus, which is not the case.
I heard one analogy which comparedthe filtering action to shooting an arrow. Imagine shooting an arrow at a target 70 yards away. You're a good shot and all arrows hit the target. Now imagine that the space between you and the target is full of trees and branches. The space betwen the trees and branches tends to be far larger than the cross-section of the arrow, yet the chances of an arrow making to the target are greatly diminished. An imperfect analogy, to be sure, but I liked it.
LisaL
(44,962 posts)muriel_volestrangler
(101,146 posts)It (#11 in the picture on CNN) looks like it's made out of a shiny material.
At first, I was using a neck gaiter made out of fleece - with a drawstring around the top edge (again, not something theirs seems to have). However, I haven't used it for some time, and in case their shiny 'fleece' is somewhat related to real fleece material, I won't use it again.
ProfessorGAC
(64,413 posts)A lot of those gaiters are made of materials other than fleece.
I wonder if a tighter knit of something like athletic wear would be more effective.
Obviously, the broader the weave, the less effective it will be.
LisaL
(44,962 posts)Which apparently breaks large droplets into small droplets, thus making mask worse than no mask at all in protecting other people.
LeftInTX
(24,541 posts)It is too vague.
14 masks used in the test, but they don't bother to assign the mask number to their results...
mucifer
(23,371 posts)Limitations of the study are also in the article.
I just thought it's important people know about the neck fleece.
LeftInTX
(24,541 posts)LisaL
(44,962 posts)You can see how well each mask did in the figure.
LeftInTX
(24,541 posts)Which one is poly/cotton, PolyProp, swath, Cotton1,2,3,4,5 etc etc?
The N95 is obviously #14, Surgical is #1, Fleece is #11 Bandana is #12. But what are #2, #3, #4 etc? You can't tell the material just be looking at a picture. Which one is the MaxAT? #6, #9, and #10 look identical to me...which materials are they made of and where are the in results?
They need better descriptions of each of the masks....
LisaL
(44,962 posts)It has a table.
sl8
(13,584 posts)ismnotwasm
(41,917 posts)I fold them for protective layers. They are annoying and have turned into hair bands. Im just using regular masks
LisaL
(44,962 posts)They did worse than no mask at all.
ecstatic
(32,566 posts)enough getting people to buy and wear masks. We're over 5 months into this disaster, ffs! At the store, I see a lot of people wearing masks with the valves and all I can do is shake my head and hope that everyone survives this clusterf*ck. Everything about this crisis has been mishandled from day 1.
LisaL
(44,962 posts)It did better than some of the cottons or a fleece.