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  • sharon sanders
    replied
    bump this

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  • Mary Wilson
    replied
    Counterfeit Covid Masks Are Still Sold Everywhere, Despite Misleading Claims

    Rising Covid cases have spurred a return to mask-wearing in the U.S. and overseas, at a time when flawed KN95s from China continue to dominate e-commerce sites.

    Nov. 30, 2021Updated 12:32 p.m. ET

    By Andrew Jacobs

    The N95 mask, arguably the most essential and coveted piece of pandemic protective gear, is no longer a rare commodity, thanks to the return of Chinese imports and a resurgence in U.S. domestic production.

    ... Consumers who try to purchase N95 masks, mainly on Amazon, are often led to vendors selling fake or poorly made KN95s, a Chinese-made mask that is often marketed as an N95 equivalent despite the lack of testing by U.S. regulators to confirm virus-filtering claims.

    In fact, KN95 masks offered on Amazon and through other retailers are being sold without authorization for use in health care settings from the Food and Drug Administration, which last July revoked its emergency use authorization for imported masks that lack approval from the Centers for Disease Control and Prevention — a category that includes all KN95s from China.

    They include brands like Boncare, which is produced by a company that has repeatedly failed federal testingstandards; Yotu, whose manufacturer has also failed European Union testing; and ChiSip, an Amazon top seller whose manufacturer, Chengde Technology, was cited by the C.D.C. for falsely claiming approval by federal regulators.

    https://www.nytimes.com/2021/11/30/h...?smid=tw-share

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  • sharon sanders
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    bump this

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  • sharon sanders
    replied
    Sadly Dr. Modesto passed away in 2013 but her contributions live on here.

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  • kiwibird
    replied
    Originally posted by T. Modesto,PhD View Post
    From the New York Times

    http://www.nytimes.com/2006/10/25/op...th&oref=slogin

    Face Facts
    By LAWRENCE M. WEIN
    Published: October 25, 2006

    Stanford, Calif.

    DESPITE all the attention given to anthrax and smallpox and potential weapons of mass destruction, pandemic influenza is probably the world's most serious near-term public health threat. If a strain similar in effect to the 1918 Spanish flu (which killed tens of millions of people worldwide) emerges in the next several years, it is highly likely that an effective vaccine will not be available during the pandemic's first wave, that we won't have enough antiviral drugs for large-scale prophylactic use, and that hospitals will be too overwhelmed to treat most cases.

    Consequently, as in 1918, we will need to combine medical efforts with voluntary and forced social changes ? closing schools and churches, canceling public gatherings, keeping workers at home ? to hinder the flu's spread. Our government must draw up a plan for educating the public about effective nonpharmaceutical interventions like hand washing and face protection like masks.

    A prerequisite for doing so is determining the biggest culprit in spreading influenza: droplet transmission, in which an infected person sneezes or coughs directly into the mouth, nose or eyes of someone who is susceptible); contact transmission, in which virus is transferred via hands either directly, say, through a handshake, or indirectly through an object like a doorknob; and aerosol transmission, in which evaporated virus-containing particles are inhaled.

    Remarkably, this issue has not been resolved: the Department of Health and Human Services' Pandemic Influenza Plan states that "the relative clinical importance of each of these modes of transmission is not known." As a result, the government enthusiastically endorses frequent hand washing ? which would reduce contact transmission, and costs nothing ? but remains noncommittal about face protection. While the government says that it might be beneficial, it doesn't make respirators or masks available. Yet face protection would guard against aerosol and droplet transmission, and even reduce contact transmission by making it difficult to place fingers into one's mouth or nose.

    A Stanford graduate student, Michael Atkinson, and I recently performed a detailed study of the routes of transmission, using data on influenza and on rhinovirus, which causes the common cold. Our findings suggest that the dominant mode of transmission for influenza is aerosol ? implying that hand washing will make little difference. This is consistent with the views of leading researchers several decades ago, views that have somehow been forgotten by the public health community.

    We found that ventilation, like placing a fan in an open window, and humidifiers (most influenza strains survive in the air for much less time when the humidity is raised to about 65 percent) can reduce transmission slightly. Sleeping in separate bedrooms (and working in separate offices) can help even more.

    But the single most effective intervention is face protection. And because roughly one-third of influenza transmissions occur before an infected person exhibits symptoms, these precautions should be taken whenever people are in the same room throughout the pandemic period.

    There are two kinds of face protection: N95 respirators, as worn by construction workers, for instance, and surgical masks of the sort worn by dental hygienists. (The respirators cost roughly a dollar apiece, the surgical masks 10 cents.) Their efficacy in preventing aerosol transmission depends on three factors: the extent to which the face filter prevents virus particles from passing through, how tightly the device fits and ? most important ? how long people can be coerced into wearing them.

    To our surprise, we found that the filters in surgical masks, although not as good as the filters in N95 respirators, are still quite effective. And although a surgical mask fits much more loosely and allows more leakage, it's also more comfortable ? and therefore likely to be effective because it's used more. Wearing nylon hosiery over a surgical mask essentially eliminates the face leakage, making this combination a practical, albeit macabre, alternative. The less comfortable N95 respirators would probably result in lower compliance.

    The government doesn't stockpile masks and respirators, and the manufacturers aren't able to produce a huge number of them quickly. But the way forward seems clear: the government needs to build up a supply of respirators and masks just as it does with vaccines and antivirals. It should first hire a whiz-bang design company to create, within one month, a surgical mask that comfortably adheres to the face, and then decide on the appropriate mix of respirators and masks. Next, it needs to sign contracts with manufacturers to stockpile masks and respirators, relieving the manufacturers of liability issues.

    Although there is very little technological risk involved (masks and respirators are easier to make and safer to use than vaccines), several issues need to be ironed out. First, the effectiveness of N95 respirators and masks varies widely. The government needs to educate the public (the brands are anonymous in the published studies) and should stockpile only the most effective brands.

    Also, if respirators and masks are discarded daily, as they are in many hospitals, the national demand during a three-month pandemic could be 10 to 20 billion, and the cost for respirators for a family of four several hundred dollars. Such waste isn't necessary. The virus does not survive longer than a few hours on the material used for masks and respirators, so they should be re-used until they disintegrate.

    The government and the public health community must switch mindsets, from the current perspective of protecting workers paid to do a dangerous job everyday, to that of providing citizens with the tools to best protect themselves during a pandemic.

    It may take 18 months to build a stockpile of respirators and masks, so there is no time to lose. The American people's faith in their government will be seriously undermined if, along with larger measures like school closings, it cannot provide effective face protection for its citizens during a deadly pandemic. Masks and respirators may be our main lines of defense during a pandemic.

    Lawrence M. Wein is a professor at Stanford's graduate school of business.
    Very interesting - this is a very salient thread - given that we are now dealing with Covid. Surgical masks should be changed every two hours. A more recent study has been done.
    https://www.nature.com/articles/s41598-020-72798-7

    All of the above experiments were also repeated with vented N95 respirators, albeit with only 2 participants (due to shortages at the time of testing). The small sample size precludes significance testing, but in general the particle emission rates of the two tested were comparable to the surgical mask and unvented KN95 in terms of reduction in the overall emission rates.
    I am not sure that Delta should have banned vented N95's on this basis. https://www.travelandleisure.com/air...sks-with-valve


    Thank you to T. Modesto,PhD for this thread.

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  • gsgs
    replied
    Re: Masks & suggestions for how to use them

    can someone post pictures, how the filtermaterial looks under the microscope ?

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  • Lynda
    replied
    Re: Masks & suggestions for how to use them

    Wow. There's a lot of misinformation here.

    Once a mask begins to break down, it begins to get horizontal collapse which alters the fit, rendering it useless.

    Viruses can live much longer than that on environmental surfaces, especially in the cold.

    Anyone who has ever worn a Nano knows that they don't even come close to fitting, even if they did work, and there's absolutely no reason to think they do work. All research is private, paid for by them. In fact, they recently changed the shape, admitting that the old shape was a problem. So what about the millions of masks already sold at a HIGH price? If BF comes, the people depending on those masks will be exposed. They are genius marketers.

    DEPARTMENT OF HEALTH & HUMAN SERVICES Public Health Service
    __________________________________________________ ______________________________________
    June 29, 2006
    NIOSH RESPIRATOR USERS NOTICE: CAUTION
    Subject: Misleading representation of the Nano Guard Particulate Respirator as a NIOSH Approved N-95 Respirator


    It has been brought to the attention of the National Institute for Occupational Safety and Health (NIOSH) through the process of a product audit, that 2HDistributors is representing and selling a Particulate Respirator called Nano Guard as a NIOSH approved respirator.

    The Nano Guard respirator is individually packaged and improperly labeled with the NIOSH and Department of Health and Human Services logos. Additionally, the label contains a NIOSH approval number, TC-84A-4175, which was not issued to 2HDistributors.

    The Nano Guard package label is illustrated below.

    A NIOSH approval is issued to a respirator only after it has been evaluated in the laboratory and found to comply with all the requirements of Title 42, Code of Federal Regulations, Part 84, including a review of the manufacturers quality plan.

    The Nano Guard N95 Particulate Respirator is not certified and approved by NIOSH.

    Sincerely yours,
    Heinz W. Ahlers
    Chief, Technology Evaluation Branch
    National Personal Protective Technology Laboratory
    Centers for Disease Control
    and Prevention (CDC)
    National Institute for Occupational
    Safety and Health (NIOSH)
    National Personal Protective
    Technology Laboratory (NPPTL)
    P.O. Box 18070
    Pittsburgh, PA 15236-0070
    Phone: 412-386-4000
    Fax: 412-386-4051
    ----end document

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  • Jonesie
    replied
    Re: Masks & suggestions for how to use them

    Originally posted by T. Modesto,PhD
    Wearing nylon hosiery over a surgical mask essentially eliminates the face leakage, making this combination a practical, albeit macabre, alternative. The less comfortable N95 respirators would probably result in lower compliance.
    That's amusing. I mentioned in a really old post...a year or more ago,, as a joke, to pull a nylon stocking over the face to hold down a mask. I never thought someone would take the ball and run with it!

    Actually. if stuck with just a surgical mask, use micropore tape to tape it to the face. then you have better protection and close the gaps.

    But then. if the tape refuses to stick, an old nyon might be a good alternative.
    Red fishnet stockings might be sexier and less macabre, but probably won't work as well at closing gaps..

    Micropore tape is better than wearing a nylon stocking over your head, alarming the public, and being chased around by cops wherever you go!

    3M makes the tape:
    http://www.qualitymedicalsupplies.co...QMS/CTGY/73-MP

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  • sharon sanders
    replied
    Re: Masks & suggestions for how to use them

    Thanks everyone for a great discussion on masks.

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  • sameo416
    replied
    Re: Masks & suggestions for how to use them

    Laidback Al has got it right.

    An info sheet on the preparation for a fitting of an N95 mask:

    http://www.orcbs.msu.edu/biological/...al/n95_fit.pdf

    They state that even one day's growth of facial hair can impair the sealing of an N95 type mask. You can tolerate more facial hair with a half- or full-face respirator but it can still compromise the seal. The razor idea is a great one - if you're in a life-threatening situation the loss of some beard is probably a good trade-off.

    A further consideration for the re-use of disposable masks is the danger of increasing the risk of infection. If you re-use a mask in a contaminated environment pathogens will become concentrated within the filter material. Once the filter material is damp from moisture in the wearer's exhaled breath, it can also provide a suitable growth media for some pathogens. This could lead to a mask user breathing through a higher concentration of pathogens than would otherwise be present, and potentially increasing their risk of infection.

    In trying to 'clean' a disposable mask you would need a technique that could neutralize pathogens contained within the rabbit warren of air passages in the filter material. Contaminents do not rest only on the outer surface, but are distributed through the filter media - the filter works by providing twisting paths that make it difficult for particles to penetrate. I'm not aware of any process that would achieve this (steam autoclaving maybe, but how would this affect the filter material?).

    Also, once you've worn a mask for a period of time dust in the air begins to increase the breathing resistance by blocking some of the air pathways. This tends to increase filter efficiency (good) but the increased resistance also causes more leakage (bad).

    They're disposable masks for a reason. These same comments apply to all air-purifying filters whether on a disposable N95 mask or in a canister filter attached to a full-face respirator.

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  • Laidback Al
    replied
    Re: Masks & suggestions for how to use them

    Originally posted by DRJJ
    Three questions
    ..... 2. Should we include razor blades in emergency preparedness kits for shaving, so that masks may be fitted to male faces properly?
    That is an excellent suggestion. Generally, most face masks on men with full beards do not pass the fit test and seal safely.

    Originally posted by DRJJ
    Three questions
    ..... 3. Can used masks be rendered safe with exposure to several days of sun or saturation in bleach solution?
    Short answer - No.

    see:

    http://www.flutrackers.com/forum/showthread.php?t=5342


    and

    The effectiveness of a face mask decreases as the mask material becomes saturated, so re-use or extended use is not wise if you are in a contaminated environment. This is exacerbated if you are wearing a mask in a cold environment as there is increased condensation on the mask material. There are N95 type masks with an exhaust vent that protects the filtering surfaces from compromise by moisture. (I've worn N95 masks outdoors in the Canadian winter and had most of the filter surface blocked by frost in short order)

    The WHO recommends changing surgical type masks every two hours and N95 masks every 6-8 hours. (http://www.wpro.who.int/sars/docs/masks/masks_faq.asp)
    from thread: http://www.flutrackers.com/forum/showthread.php?t=12144

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  • DRJJ
    replied
    Re: Masks & suggestions for how to use them

    Three questions



    through second-hand contact of a contaminated surface or person (and then through the skin by a cut or cross-contamination of a mucus membrane).

    1 What is the danger of contamination through vaginal mucus membrane through toileting activities for females?

    2. Should we include razor blades in emergency preparedness kits for shaving, so that masks may be fitted to male faces properly?

    3. Can used masks be rendered safe with exposure to several days of sun or saturation in bleach solution?

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  • Sisterobin
    replied
    Re: Masks & suggestions for how to use them

    Can anyone tell me at what temperature does the BF virus die? Is it possible to 'bake' a paper or cloth mask at a low temperature {say 150 or 165 degrees} or pressure can it like an auto clave to kill the germs? Or perhaps a food dehydrator? They can reach those temperatures.

    I know this is a bit 'out' there, but in reading all the posts on FT I've not found this subject addressed.

    Sisterobin~

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  • sameo416
    replied
    Re: Masks & suggestions for how to use them

    Originally posted by DeadAhead
    It should be noted that N95s, EVEN IF FITTED PROPERLY, do NOT reliably block viral particles.

    The current strain of the H5N1 virus, or avian flu, is approximately 0.1 micron (100 nm) in size.

    Examples of particle size:

    Viruses 0.02 to 0.3 microns - N95 mask not effective
    Bacteria 0.5 to 10 microns - N95 mask effective
    Mold spores 1 to 70 microns - N95 mask effective
    Fungi 2 to >200 microns - N95 mask effective

    Best, DA
    All true.

    I have not seen any research suggesting that individual viral bodies can become airborne (any comments from those with medical backgrounds?). Pathogens are usually transmitted attached to droplets or dust sized in the 1-10 micron range, which is why N95 masks are used in hospitals for infection control both ways (patient <-> caregiver) and against viral and bacterial threats. Even 'weaponized' pathogens used as biological warfare agents are in the 1-5 micron range.

    Also recall that '95' means 95% effective, so the mask will let through 5% of particles 0.3 microns or larger even though it is rated for that size of threat.

    This is the reason why anyone working with known nasty pathogens will wear self-contained breathing apparatus. Your own clean air supply is the only way to ensure the lowest chance of infection. The CDC recommends the minimum level of protection (this is in a biological warfare situation) as a full-face mask with P-100 or HEPA filter but only if no aerosol production is present. http://www.bt.cdc.gov/DocumentsApp/A...001Protect.asp
    Last edited by sameo416; November 24, 2006, 01:16 PM.

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  • DeadAhead
    replied
    Re: Masks &amp; suggestions for how to use them

    It should be noted that N95s, EVEN IF FITTED PROPERLY, do NOT reliably block viral particles.

    The current strain of the H5N1 virus, or avian flu, is approximately 0.1 micron (100 nm) in size.

    Examples of particle size:

    Viruses 0.02 to 0.3 microns - N95 mask not effective
    Bacteria 0.5 to 10 microns - N95 mask effective
    Mold spores 1 to 70 microns - N95 mask effective
    Fungi 2 to >200 microns - N95 mask effective

    Best, DA

    Leave a comment:

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