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When I go out to one of my death scenes, I am required to wear an N95. No surgical mask, no cloth mask. Used to have to have a face shield on also but that got squashed. They never stayed put anyway..

Those rules come down from the state DOH. Not my office. State says anything other than an N95 is pretty much useless, but what we hear changes day to day. Who knows...

.

Look at the November 2020 guidance I posted as well as the studies they cite in finding masks do help.... Or not.. your call.

I can see you regard the CDC as a reliable authoritative source, and I agree. Here is their webpage on masks in which they offer their conclusion that masks have some efficacy and in which they repeatedly urge-mask-wearing:

https://www.cdc.gov/coronavirus/2019-ncov/more/masking-science-sars-cov2.html

And here, for ease of your review, is the "Conclusion" section of that webpage. More details are available if you click on the link above, and some studies are discussed there:

Experimental and epidemiological data support community masking to reduce the spread of SARS-CoV-2. The prevention benefit of masking is derived from the combination of source control and personal protection for the mask wearer. The relationship between source control and personal protection is likely complementary and possibly synergistic14, so that individual benefit increases with increasing community mask use. Further research is needed to expand the evidence base for the protective effect of cloth masks and in particular to identify the combinations of materials that maximize both their blocking and filtering effectiveness, as well as fit, comfort, durability, and consumer appeal. Adopting universal masking policies can help avert future lockdowns, especially if combined with other non-pharmaceutical interventions such as social distancing, hand hygiene, and adequate ventilation.

Masks vs. face coverings
 

One point to keep in mind, a N95 face mask, the one with the plastic exhalation valve molded into the filter media, when properly worn, protects the wearer.

The face coverings (surgical masks, cloth masks, etc.) when properly worn, are used to protect others.

An interesting dilemma, we are evaluating radiological suit-up (think a hazardous material suit up) activities at work where an entrant is assisted by an attendant during the suit-up process. Full face respirators protect the wearer from inhaling contamination, unwanted particulate, or noxious fumes. They also incorporate an exhalation valve, allowing the wearers breath to escape. If the wearer is asymptomatic, they could be exhaling virus laden droplets and aerosols during this suit up process, putting the attendant at risk. The close proximity of this type of suit up requirement has already exposed some of our workers to Covid-19, infecting a handful of workers before the transmission risks were fully recognized. Difficult to do effectively and efficiently.

[QUOTE=Superman;11197412]I can see you regard the CDC as a reliable authoritative source, and I agree. /QUOTE]

Actually I don't trust the CDC, they have conflicting reports. I guess they feel they have to advise us of some form of "protection". It would sound so hopeless to tell us there's nothin you can really do but avoid people

Remember when we shut down the entire damn country for that same purpose and it didn’t do any good?

[QUOTE=gregpark;11197444] You cited the CDC. And now that the CDC says something you don't like.....

"We" have never "shut down the entire damn country," not even close. What on earth are you referring to? Health directives that prohibited indoor gatherings? How do you know that those did not do any good? The Covid numbers could have been triple with absolutely nothing done.

Your opinions really seem to be political, not medical or scientific. That's ok, as long as you realize it. They don't have any value wrt controlling the pandemic, though.

Of course masks are ineffective
http://forums.pelicanparts.com/uploa...1611627452.jpg
The CDC study said so just a month ago
They change their minds? and apparently Fauci changed his mind at one point too

Here's more of the study I cited earlier. Straight from the US CDC

..........
In our systematic review, we identified 10 RCTs that reported estimates of the effectiveness of face masks in reducing laboratory-confirmed influenza virus infections in the community from literature published during 1946–July 27, 2018. In pooled analysis, we found no significant reduction in influenza transmission with the use of face masks (RR 0.78, 95% CI 0.51–1.20;*I2*=*30%, p = 0.25) (Figure 2). One study evaluated the use of masks among pilgrims from Australia during the Hajj pilgrimage and reported no major difference in the risk for laboratory-confirmed influenza virus infection in the control or mask group (33). Two studies in university settings assessed the effectiveness of face masks for primary protection by monitoring the incidence of laboratory-confirmed influenza among student hall residents for 5 months (9,10). The overall reduction in ILI or laboratory-confirmed influenza cases in the face mask group was not significant in either studies (9,10). Study designs in the 7 household studies were slightly different: 1 study provided face masks and P2 respirators for household contacts only (34), another study evaluated face mask use as a source control for infected persons only (35), and the remaining studies provided masks for the infected persons as well as their close contacts (11–13,15,17). None of the household studies reported a significant reduction in secondary laboratory-confirmed influenza virus infections in the face mask group (11–13,15,17,34,35). Most studies were underpowered because of limited sample size, and some studies also reported suboptimal adherence in the face mask group.

Disposable medical masks (also known as surgical masks) are loose-fitting devices that were designed to be worn by medical personnel to protect accidental contamination of patient wounds, and to protect the wearer against splashes or sprays of bodily fluids (36). There is limited evidence for their effectiveness in preventing influenza virus transmission either when worn by the infected person for source control or when worn by uninfected persons to reduce exposure. Our systematic review found no significant effect of face masks on transmission of laboratory-confirmed influenza
.........
I don't know what to believe from an agency that talks out of both sides of the mouth if that's the case. I guess I'll just trust my own common sense telling me that a loose fitting mask is not going to protect either way from a microscopic bacteria

We were pretty well shut and locked down for quite a while. I was actually amazed at how shut down LA was.
The 10 and 110 freeway and Sunset Blvd., for example. It was remarkable.

http://forums.pelicanparts.com/uploa...1611631936.jpg
http://forums.pelicanparts.com/uploa...1611631936.jpg

That looks apocalyptic.

It was

greg,
Read the limitations in the findings of the studies the CDC used in determining whether masks work.... Or not... your call. And please, make sure you use that meme a lot! It's exactly how a virus works and that vapor is exactly what the mask is trying to stop! They're useless! Don't wear them! Go on out and get your "herd immunity"!

Just found out one of our neighbors passed away last night . He had recently tested positive for Covid along with his adult son and daughter in law that lived there . Don't know anything about if they were mask wearers or not and really don't care . Add another one to the pile of folks that have passed from the virus 🙁 . He was a hospice worker so I am sure that increased his exposure . Sad

well...
Yoda now thinks wearing 2 mask might work....


Rika

You have that last part wrong. Emphatic, but wrong.

When respiratory viruses are shed via droplets, even more virus particles are shed in sub-droplet size.

Please make a note of it.

Or research this yourself.

A quick search on that claim gave me this light reading on the topic: https://www.pnas.org/content/115/5/1081

a snippet from that link.

To me, this whole thing should be an eye opener to every American... but it won't be. We were able to make planes, bombs, tanks and guns for a war effort but we can't produce enough masks to keep people in a healthcare environment protected. Men went off to fight faced with almost certain death in some instances... today you can't get them to put a mask on or to get a vaccination. The "greatest generation" has to look down in disbelief at what has happened to this country.

Mask wearing was maybe 10% here until the fall. We had 1 or 2 cases a week, then it became 50 a week and you slowly started seeing more masks. We're now at 3236 cases (8% of the population) and it's rare to see someone without a mask.