Ron Chusid Jan 16, 2023
WHO updates their recommendations to advise masking by "anyone in a crowded, enclosed, or poorly ventilated space" regardless of local epidemiological conditions in light of its global spread.
#COVID #BringBackMasks
https://www.who.int/news/item/13-01-2023-who-updates-covid-19-guidelines-on-masks--treatments-and-patient-care
WHO updates COVID-19 guidelines on masks, treatments and patient care

The update is part of a continuous process of reviewing such materials, working with guideline development groups composed of independent, international experts.

Show threadNathanael NerodeJan 16, 2023

@rchusid Now we just need @WHO to mention #N95, #N99, #P100, #FFP2, #FFP3, #P3, #KF94, and/or #KN95 #elastomeric #respirators -- the ones which *work* -- rather than just vaguely saying "masks".

Cloth & surgical junk masks are 30% effective -- better than nothing.

#N95 and reusable #P100 #elastomeric #respirators are >95% effective -- MUCH better. And they're cheap enough.

Show threadSpencer W HunterJan 16, 2023
@neroden @rchusid
My favorite @masknerd quote:
“Cloth masks are better than nothing… but they’re a lot closer to ‘nothing’ than ‘better.’”
Show threadDavid Mitchell Feb 7, 2023

@neroden @rchusid @masknerd @swhunter7

Worth noting too, that the range of ‘things’ that fall under ‘cloth mask’ is very wide, from multilayered, well made and fitted masks with quality fabrics to a single layer gaiter pulled over the face.

Show threadSpencer W HunterFeb 7, 2023
@DavidM_yeg @neroden @rchusid @masknerd
I recall, in the time before the general public could access medical-grade masks, that some cloth masks made from certain chiffons that could carry an electrostatic charge were claimed to have filtration efficiencies similar to N95s; but I know of no accessible empirical test that verifies that.
Show threadRon Chusid Feb 7, 2023
@swhunter7 @DavidM_yeg @neroden @masknerd Yes, early on there were claims for this. It may or may not be accurate but these days it just seems simpler to go with an N-95, or at least a tight fitting KN-95.
Show threadTransitBiker
@rchusid @swhunter7 @DavidM_yeg @neroden @masknerd the problem with KN95’s is that 1. It’s not an independently verified standard 2. People often wear them without using the nose strip to actually seal against the face & 3. Earloop stuff is nowhere near as sealed as headband stuff. KF94’s for their odd construction are actually certified & actually work despite the earloop design. KN95’s should honestly not be seen as a real option.
Feb 7, 2023 at 1:37pmWeb
Show threadSpencer W HunterFeb 7, 2023
@TransitBiker @rchusid @DavidM_yeg @neroden @masknerd
I carry the Armbrust KN95 with me at all times as a backup (NASA maxim: never rely on the backup). Works great when I have to clear the dryer screen & don’t want to breathe the lint.
Show threadRon Chusid Feb 7, 2023
@TransitBiker @swhunter7 @DavidM_yeg @neroden @masknerd It depends on the mask. Fit and proper use make a huge difference. I use N-95s when with patients but will sometimes quickly throw on a KN-95 when doing something like running into a store. I only use ones which do fit me tightly and of course use a tight nose strip. I also have some KF-94s. Some have straps to tighten which I like but I have others which I don't use as they do not have as good a fit.
Show threadTransitBikerFeb 7, 2023
@rchusid @swhunter7 @DavidM_yeg @neroden @masknerd Yes! One of the big issues is people have different shaped faces and you want to find the best most economically sensible, most protecting mask for your face shape and use case scenario. I really do wish there was a one size fits all very inexpensive ubiquitous solution for this.