Without a filter, the valved masks protect the wearer but not his interlocutor. They represent a certain perspective.Originally Posted by Balisong
Without a filter, the valved masks protect the wearer but not his interlocutor. They represent a certain perspective.
Ignore Alien Orders
I truly thought they had a built in filter though?
Here are the masks they tested. There is no way that valved mask is an N95? More like a kn95.
Also, the valved kn95 does a better or relatively the same than the other types of masks especially compared to no mask.
Go to page 8 of the pdf to see the corresponding table for the masks in the picture.
https://advances.sciencemag.org/cont...bd3083/tab-pdf
Mask, Name Description 1, ‘Surgical’ * Surgical mask, 3-layer 2, ‘Valved N95’ N95 mask with exhalation valve 3, ‘Knitted’ Knitted mask 4, ‘PolyProp’ 2-layer polypropylene apron mask 5, ‘Poly/Cotton’ Cotton-polypropylene-cotton mask 6, ‘MaxAT’ 1-layer Maxima AT mask 7, ‘Cotton2’ 2-layer cotton, pleated style mask 8, ‘Cotton4’ 2-layer cotton, Olson style mask 9, ‘Cotton3′ 2-layer cotton, pleated style mask 10, ‘Cotton1’ 1-layer cotton, pleated style mask 11, ‘Fleece’ Gaiter type neck fleece 12, ‘Bandana’ * Double-layer bandana 13, ‘Cotton5′ * 2-layer cotton, pleated style mask 14, ‘Fitted N95’ N95 mask, no exhalation valve, fitted ‘Swath’ Swath of mask material, polypropylene ‘None’ * Control experiment, no mask
Last edited by Doug; 08-10-2020 at 11:45 PM.
Those masks are Personal Protective Equipment generally intended to offer the wearer a high level of protection from industrial contamination. They were never intended to be Medical or Societal Protective Equipment. I have a few cases of them for use around the garage or when smoke from wildfires makes the air unhealthy to breathe.
The exhaust valve keeps the mask a lot cooler which makes it a lot more comfortable when wearing for extended periods of time. It also makes a world of difference during during heavy exertion (without the valve, you breathe in a fair amount of your previous exhale). In non-covid times, these valved marks are the main type stocked at department or hardware stores in this area:
Here:
Last edited by 0ddl0t; 08-11-2020 at 01:27 AM.
I was surprised by the results for using a neck gaiter ("fleece") being worse than no mask. Apparently this is due to large droplets being converted to smaller droplets. Another takeaway for me is that if this is a good proxy of protection for others, the easiest and cheapest way to protect others may be a disposable surgical or procedure mask especially as supply chains have caught up somewhat.
Another study which would back up the use of masks to help reduce spread showed that viral load for asymptomatic patients was close to or equal to that of those displaying symptoms. Link here: https://jamanetwork.com/journals/jam...rticle/2769235
Summary: "Many individuals with SARS-CoV-2 infection remained asymptomatic for a prolonged period, and viral load was similar to that in symptomatic patients; therefore, isolation of infected persons should be performed regardless of symptoms."
...and yet they are approved for us on duty at this point.
But hey, I was an idiot for saying that improper masks worn improperly were showmanship over effectiveness so whatever. Something is better then nothing, etc. etc.
Sorta around sometimes for some of your shitty mod needs.
The appearance of doing something is just as good as doing something...
Minor pet peeve of mine: The Bandana, Nothing, and Fleece entries are basiclly identical. The noise in those data sets is too much to draw any conclusions beyond "bandana/fleece don't work".
The results might also suggest that the study isn't perfect.
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