FACE MASK v COVID

[RoyGBiv]

Just going to cut to the chase and hope there are some experts here who have some solid info.
Since face mask are required in some places it seems prudent to lay in a supply.
Ive noticed a lot of the N 95 medical mask dont seem to fit so well. Gaps around the face. Then there is the cost of those mask especially if you need a new one daily.

Speaking on N/KN95...

I am not any kind of qualified expert. I've been dabbling in masks for 3 months. I was a Chemist long ago, FWIW.
This is my OPINION. Not medical advice.

I've tried to fit more than a dozen KN95 and N95 masks to my face over the past 3 months. I've sent them to customers who know what they're doing, and we've compared some results. The reality is that your face shape, the mask dimensions, your attention to fitting.... all matter.

Most masks you find available these days are flat-fold. Well, my nose certainly won't seal under a metal nose-bridge triangle. You need to spend some time matching the shape of the un-folded mask to the shape of your nose. I've found that most masks CAN be shaped to fit me correctly, but some are better than others.

Size matters. The Honeywell H930 is a great mask.... for my wife and kids. Not for me. Too small.
The H910 however, is slightly bigger and fits me awesomely. And it has a foam pad that seals under my eyes. And it's an ear loop. Bonus.
One of my customers swears by the H930. I assume their staff are all microsyphalic, like my family.

Bottom line... you can make most masks fit reasonably well, but not every mask fits every face.

For running errands and such, I find I'm using 1 mask every 3-4 weeks. The package says 8 hours. I figure 5-6 hours over 3 weeks is ok. Just my opinion.
Put on, buy groceries, hang on hook for 24 hours. Sanitize hands before and after donning and doffing.

There are some great looking fabric masks .... There's a thread going on it here. I gave my kid a fabric mask with a charcoal filter. Supplosed to be >95% filtration. He handles it WAY better than an N95 with ear loops. The velcro is way better for him than elastic ear loops.

The better the filtration, the less likely it will be for you to get infected by others.
You have to strike whatever balance is best for you between effectiveness, comfort, availability, etc.

IMO... I'm not going into any enclosed spaces without a mask that protects my airway. N
Outside in the breeze... depends on the exposure time. Exercising... No mask, distance.
Social distance cocktails in the yard... maybe no mask at all, if I am sitting upwind.

[UNM1136]

We have an annual fit test for N95s. Tester goes over the propper way to don the mask, and then puts on a huge hood on you into which they spray a very bitter aerosol compound, while you move your head around and then read a printed paragraph. If you taste the aerosol your mask is not sealed, and you get to repeat everything. We have a number of Bio-chemical labs in the area, including one the FBI investigated during the anthrax scare after 9/11.

A more political question that several co-workers is asking is if stay at home and social distancing work, why are masks now manditory? If masks work why were there stay at home orders in effect for so long. In my state positive tests are up, but hospitalizations and deaths are on the way down. That was originally the goal with all of this, so why are we being threatened with fines for not wearing masks, on the basis of an executive order, and not statute. Why are we not hearing about herd immunity any more? The scientists seem to go back and forth, and like it or not, the issue is politicized, so each side is looking for science types who support their positions...

pat

[TiroFijo]

Herd inmunity is far, FAR away...

Even in countries with extremely severe and devastating outbreaks like Spain, studies estimate around just 5% of the population has developed antibodies. And no one knows the degree of inmunity or long it would last. Compare to the 2/3 needed for herd inmunity.

https://www.bbc.com/news/world-europe-53315983

We'll likely have to live adjusted for COVID (and that means different things dependinf on where you are an many variables) for a long while until a vaccine arrives.

[Nephrology]

I have afew boxes of disposable N95s I wear when indoors around my apt complex. Been reusing them to make them last. The elastic is clearly wearing out on some of the older ones - I strongly doubt they fit terribly well anymore.

Preparing to go back to lab soon-ish, and will be using a 3M 1/2 mask respirator with P100 filters. It's clunky, hot, and makes me feel a bit ridiculous, but it is way more comfortable and provides much better protection than my N95s.

When I am walking around outside (and can easily steer clear of people) I generally take my mask off just to get some fresh air. I am not as worried about transmission in well ventilated outdoor places than I am inside.

A more political question that several co-workers is asking is if stay at home and social distancing work, why are masks now manditory? If masks work why were there stay at home orders in effect for so long. In my state positive tests are up, but hospitalizations and deaths are on the way down. That was originally the goal with all of this, so why are we being threatened with fines for not wearing masks, on the basis of an executive order, and not statute. Why are we not hearing about herd immunity any more? The scientists seem to go back and forth, and like it or not, the issue is politicized, so each side is looking for science types who support their positions...

pat

I obviously can't speak for policy makers, etc, but my basic understanding is as follows:

- Staying at home is, strictly speaking, safer than going out with/without a mask
- There isn't really a lot of quality evidence on how well masks protect the user from infection - this is not something most people cared about until recently - so the degree of protection they offer is hard to state with certainty
- Initial forecasts suggested the virus was going to spread much more rapidly than it has, so staying at home seemed like a reasonable way to prevent healthcare systems from being overwhelmed
- Really perilous economic situation, plus general social/cultural climate in USA right now (which I would describe as "don't give a fuck!"), makes returning to shutdown almost untenable
- given all of the above I guess the feeling is that city/state govt's may a well make people wear a mask if they can't keep them at home
- In the case of private businesses, at least, they probably feel safer to require masks than open themselves to lawsuit if a customer gets sick.

As for herd immunity that's a big question that's still all over the place as far as I know. There seems to be a lot of variance in the quality of the serum antibody tests so I don't know what the most accurate estimates of seroprevalence are right now. I am sure it varies highly based on very specific demographics. I am sure in in NYC metro area there is big variance in true immunity rates by zip code. I am actually curious to see what current thinking is so i'll take a quick peek at pubmed now.

Edit: Here is more commentary on that study TiroFijo mentioned earlier re: herd immunity

[Malamute]

Question about disinfecting masks. Will they disinfect themselves by simply leaving them sit at room temp for several days? Does the virus die off at some point making them safe to wear again with no other disinfection required? How long is considered safe regarding die off of virus on fabric? Is there anything that can help disinfect without being damaging to the mask?

If nothing else, Id be fine with letting masks sit several days and just rotating use to let them sit but I dont know what time period is appropriate for that to work. In my regular routine, it can be days to a week or more before Im around any humans and need a mask, so have just been using two. When out and about Im also not normally in very close proximity to people or in a potentially highly infectious environment like a health care facility.

[Nephrology]

Question about disinfecting masks. Will they disinfect themselves by simply leaving them sit at room temp for several days? Does the virus die off at some point making them safe to wear again with no other disinfection required? How long is considered safe regarding die off of virus on fabric? Is there anything that can help disinfect without being damaging to the mask?

If nothing else, Id be fine with letting masks sit several days and just rotating use to let them sit but I dont know what time period is appropriate for that to work. In my regular routine, it can be days to a week or more before Im around any humans and need a mask, so have just been using two. When out and about Im also not normally in very close proximity to people or in a potentially highly infectious environment like a health care facility.

Yes, living viral particles on surfaces, etc will eventually die off on their own. I think some people/places use UV light to disinfect, or bake in an oven at low temp, but I'm not sure how evidence based that is really.

The big study I remember reading re: SARS CoV2 surface viability is here. The cliffnotes version is that when they applied virus to a variety of surfaces (copper, cardboard, stainless steel, and plastic) they found that on every surface but plastic there was not enough viable virus left to cause an infection after 48h. On plastic it was viable until a little over 72h.

I feel like I read a study that also looked at fabric but I am not sure I remember where it is at this point. 72h seems like a safe cutoff to me.

[Malamute]

Thank you.


I recall something about fabric, either in a post or link, in the corona thread, but it could have been a couple hundred pages back.

[Malamute]

Just remembered this, improving mask efficiency by using a pantyhone wrap to gain better fit.

https://www.npr.org/sections/goatsan...sks-study-find

[Stephanie B]

Yes, living viral particles on surfaces, etc will eventually die off on their own. I think some people/places use UV light to disinfect, or bake in an oven at low temp, but I'm not sure how evidence based that is really.

A gadget-freak relative gave us a gizmo to disinfect cell phones; we put the phone in, close the lid and it bathes the phone with UV-C for ten minutes. We've been using that for our masks.

[Nephrology]

A gadget-freak relative gave us a gizmo to disinfect cell phones; we put the phone in, close the lid and it bathes the phone with UV-C for ten minutes. We've been using that for our masks.

We use UV light to sterilize biosafety cabinet working surfaces so it definitely does something. I just dont know of any papers I could point to to show it works on viruses/other surfaces. I am sure there are some out there