There are reasons why some items are designed as “single-use” or “limited use.” For example, would you consider re-using the same sheets of standard toilet paper through multiple trips to the toilet? Of course, disposable N95 masks are not exactly the same as toilet paper. Using a N95 mask more than once may still fall within the manufacturer’s guidelines for that given mask. And while not using toilet paper according to guidelines poses risks to your butt, not following guidelines for N95 respirators could put more than your butt on the line. With the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) spreading, straying from guidelines could put the butts of everyone whom you contact on the line, which is a lot of people if you are a health care professional. Note that in this case, butt is the proverbial butt and not the actual butt. If you are wearing an N95 respirator on that end of the body, you are doing it wrong and should absolutely throw the mask away immediately.
The question of mask reuse during a pandemic was already extensively addressed over a baker’s dozen years ago. Consider what a National Academies of Science Engineering and Medicine Report from 2006 entitled Reusability of Facemasks During an Influenza Pandemic: Facing the Flu offered as one conclusion: “The committee could not identify or find any simple modifications to the manufacturing process that would permit disposable N95 respirators to be reused without increasing the likelihood of infection.”
Moreover, you can’t see all of the viruses that may accumulate in the mask during use, because they are teeny-weeny. The N95 mask is a filter and not Captain America’s shield or Iron Man’s face plate. Viruses don’t just bounce off of the mask but instead get trapped inside it. That’s why you’ve got to be super careful when handling a mask that has been used. If the outside of the mask ends up touching your face while you are removing the mask, you will actually be rubbing on your face something that collects and concentrates viruses from the air.
So, got it? In “normal” pandemic situations, science says that you should not be reusing N95 masks. But. But. The current pandemic isn’t even a “normal” pandemic situation. Yes, despite the NASEM report from over 13 years ago, despite warnings that N95 mask shortages may be a problem, did hospitals and health care systems really prepare to appropriate levels? Did they maintain adequate stockpiles to account for the additional demand that would occur with an epidemic? Did they have systems in place to make sure that their health care professionals would be protected according to what science has been saying? The current situation makes you wonder.
Well, the NASEM report did also provide recommendations on what to do if N95 mask shortages were to lead to situations where such mask reuse would be necessary. Of course, the committee may have been thinking that this could occur somewhere later during a pandemic rather than near the beginning.
For example, take a look at the letter accompanying the following tweet from when COVID-19 cases were just starting to really rise in New York City:
Saman Nematollahi @TxID_Edu
This is a very scary message from @Columbia
They will run out of ICU beds and PPE soon @Atul_Gawande @EricTopol @CMichaelGibson @drsanjaygupta @CNN @mlipsitch @MackayIM @CarlosdelRio7 @kevinmd @NIHDirector
They will run out of ICU beds and PPE soon @Atul_Gawande @EricTopol @CMichaelGibson @drsanjaygupta @CNN @mlipsitch @MackayIM @CarlosdelRio7 @kevinmd @NIHDirector
Just one N95 mask for each employee is not exactly in line with the NASEM report guidance.
The first NASEM report recommendation for reuse was to “protect the respirator from external surface contamination when there is a high risk of exposure to influenza (i.e., by placing a medical mask or cleanable faceshield over the respirator so as to prevent surface contamination but not compromise the device’s fit).” Even though the SARS-CoV2 is not the same as the flu virus, repeat is not the same as the flu virus, in this case, you may be able to replace “influenza” with “SARS-CoV2.” This is where do-it-yourselfers (DIY) who don’t have the materials and technical capabilities to replicate N95 masks may be best able to help. If they can create something that can shield or protect the N95 respirator without suffocating the user, which incidentally would be a bad thing, then this could potentially extend the effective lifetime of the respirator. Note the emphasis on the word potentially.
The second NASEM report recommendation was to “use and store the respirator in such a way that the physical integrity and efficacy of the respirator will not be compromised.” This certainly means no head butting, planned or unintentional, while wearing the respirators. But even more subtle pressure to the mask could end up deforming it somewhat. Also, the mask is not a condom or a diaphragm. You shouldn’t keep it in your pocket, wallet, purse, handbag, or fanny pack. Instead, the Centers for Disease Control and Prevention (CDC) website suggests that you “hang used respirators in a designated storage area or keep them in a clean, breathable container such as a paper bag between uses.” Also, store respirators as you would make bed arrangements for an overnight school class trip. Don’t have respirators pushed against each other: “To minimize potential cross-contamination, store respirators so that they do not touch each other and the person using the respirator is clearly identified. Storage containers should be disposed of or cleaned regularly.
“Can’t touch this” applies to everything. Minimize touching the respirator with anything that may in any way deform, contaminate, or be contaminated by the mask. The third NASEM report recommendation was to “practice appropriate hand hygiene before and after removal of the respirator and, if necessary and possible, appropriately disinfect the object used to shield it.” The CDC website recommends that you “use a pair of clean (non-sterile) gloves when donning a used N95 respirator and performing a user seal check. Discard gloves after the N95 respirator is donned and any adjustments are made to ensure the respirator is sitting comfortably on your face with a good seal.”
While there is no established method of cleaning these disposable N95 masks, some have looked at different approaches. A study published in a 2009 issue of the Annals of Occupational Hygiene evaluated five possible decontamination methods: ultraviolet germicidal irradiation (UVGI), ethylene oxide, vaporized hydrogen peroxide (VHP), microwave oven irradiation, and bleach. Two of the approaches didn’t work very well. For example, microwave oven irradiation caused the samples to melt. By the way, a N95 mask is not like cheese. Melting it doesn’t make it better. The most promising options were UVGI, ethylene oxide (EtO), and VHP, but the evidence at the time was far from conclusive.
These three approaches have since gotten more attention. For example, the ABSA International website has a link to the preprint of a manuscript has been accepted to Applied Biosafety, the association’s journal. In this case, ABSA stands for the Association for Biosafety and Biosecurity and not for the Association of Bulgarian Schools in America. The manuscript described how a team from Duke University put a cohort of N95 respirators through VHP treatment and subsequently conducted testing. The testing suggested that the masks were adequately decontaminated and retained their structural integrity and function. The manuscript also cited a 2016 study for the U.S. Food and Drug Administration (FDA) that had similar conclusions.
The findings from these studies are encouraging in what’s currently a desperate situation. However, it does not mean that getting new N95 masks shouldn’t still be a priority. N95 masks aren’t cars, where used ones may replace new ones. So many things could happen during the wearing of mask that could limit what such a decontamination procedure can do. For example, what if the mask gets splashed by liquids such as blood or other body fluids? What if the mask gets bent in any way? What if the load of microbes in the mask is so high that decontamination is tougher?
If you’ve been wearing your N95 mask for more than the manufacturer’s guidelines (or more than five times if there is no specific guidance for that mask), your mask may not really be that effective anymore. In fact, it may have become more like a sponge for microbes. The more you reuse your mask, the greater the risk. Not just for you but also for all those who come into contact with you.
Might telling people that they can reuse their N95 masks well beyond normal guidelines be a bit like telling people that they can go to a lengthy battle wearing nothing but one pair of underwear? It could them a false sense of re-assurance while leaving them very much exposed.
The only real solution to the shortage is to fix the shortage as soon as possible. Manufacturers must make many, many, many more legitimate and National Institute for Occupational Safety and Health (NIOSH)-approved N95 respirators as quickly as possible. Hospitals and health care systems need to purchase them and provide them to health care professionals without any delay. Time spent negotiating or pretending that other approaches are adequate means more and more potential deaths that could have been averted. It is a sad statement that the wealthiest country in the world can’t even provide basic pandemic protection to health care professionals, the most important people in the fight against the pandemic.
https://www.forbes.com/sites/brucelee/2020/03/30/reusing-n95-masks-against-covid-19-coronavirus-the-risks-and-options/#4a77b87cdf7e
The first NASEM report recommendation for reuse was to “protect the respirator from external surface contamination when there is a high risk of exposure to influenza (i.e., by placing a medical mask or cleanable faceshield over the respirator so as to prevent surface contamination but not compromise the device’s fit).” Even though the SARS-CoV2 is not the same as the flu virus, repeat is not the same as the flu virus, in this case, you may be able to replace “influenza” with “SARS-CoV2.” This is where do-it-yourselfers (DIY) who don’t have the materials and technical capabilities to replicate N95 masks may be best able to help. If they can create something that can shield or protect the N95 respirator without suffocating the user, which incidentally would be a bad thing, then this could potentially extend the effective lifetime of the respirator. Note the emphasis on the word potentially.
The second NASEM report recommendation was to “use and store the respirator in such a way that the physical integrity and efficacy of the respirator will not be compromised.” This certainly means no head butting, planned or unintentional, while wearing the respirators. But even more subtle pressure to the mask could end up deforming it somewhat. Also, the mask is not a condom or a diaphragm. You shouldn’t keep it in your pocket, wallet, purse, handbag, or fanny pack. Instead, the Centers for Disease Control and Prevention (CDC) website suggests that you “hang used respirators in a designated storage area or keep them in a clean, breathable container such as a paper bag between uses.” Also, store respirators as you would make bed arrangements for an overnight school class trip. Don’t have respirators pushed against each other: “To minimize potential cross-contamination, store respirators so that they do not touch each other and the person using the respirator is clearly identified. Storage containers should be disposed of or cleaned regularly.
“Can’t touch this” applies to everything. Minimize touching the respirator with anything that may in any way deform, contaminate, or be contaminated by the mask. The third NASEM report recommendation was to “practice appropriate hand hygiene before and after removal of the respirator and, if necessary and possible, appropriately disinfect the object used to shield it.” The CDC website recommends that you “use a pair of clean (non-sterile) gloves when donning a used N95 respirator and performing a user seal check. Discard gloves after the N95 respirator is donned and any adjustments are made to ensure the respirator is sitting comfortably on your face with a good seal.”
While there is no established method of cleaning these disposable N95 masks, some have looked at different approaches. A study published in a 2009 issue of the Annals of Occupational Hygiene evaluated five possible decontamination methods: ultraviolet germicidal irradiation (UVGI), ethylene oxide, vaporized hydrogen peroxide (VHP), microwave oven irradiation, and bleach. Two of the approaches didn’t work very well. For example, microwave oven irradiation caused the samples to melt. By the way, a N95 mask is not like cheese. Melting it doesn’t make it better. The most promising options were UVGI, ethylene oxide (EtO), and VHP, but the evidence at the time was far from conclusive.
These three approaches have since gotten more attention. For example, the ABSA International website has a link to the preprint of a manuscript has been accepted to Applied Biosafety, the association’s journal. In this case, ABSA stands for the Association for Biosafety and Biosecurity and not for the Association of Bulgarian Schools in America. The manuscript described how a team from Duke University put a cohort of N95 respirators through VHP treatment and subsequently conducted testing. The testing suggested that the masks were adequately decontaminated and retained their structural integrity and function. The manuscript also cited a 2016 study for the U.S. Food and Drug Administration (FDA) that had similar conclusions.
The findings from these studies are encouraging in what’s currently a desperate situation. However, it does not mean that getting new N95 masks shouldn’t still be a priority. N95 masks aren’t cars, where used ones may replace new ones. So many things could happen during the wearing of mask that could limit what such a decontamination procedure can do. For example, what if the mask gets splashed by liquids such as blood or other body fluids? What if the mask gets bent in any way? What if the load of microbes in the mask is so high that decontamination is tougher?
If you’ve been wearing your N95 mask for more than the manufacturer’s guidelines (or more than five times if there is no specific guidance for that mask), your mask may not really be that effective anymore. In fact, it may have become more like a sponge for microbes. The more you reuse your mask, the greater the risk. Not just for you but also for all those who come into contact with you.
Might telling people that they can reuse their N95 masks well beyond normal guidelines be a bit like telling people that they can go to a lengthy battle wearing nothing but one pair of underwear? It could them a false sense of re-assurance while leaving them very much exposed.
The only real solution to the shortage is to fix the shortage as soon as possible. Manufacturers must make many, many, many more legitimate and National Institute for Occupational Safety and Health (NIOSH)-approved N95 respirators as quickly as possible. Hospitals and health care systems need to purchase them and provide them to health care professionals without any delay. Time spent negotiating or pretending that other approaches are adequate means more and more potential deaths that could have been averted. It is a sad statement that the wealthiest country in the world can’t even provide basic pandemic protection to health care professionals, the most important people in the fight against the pandemic.
https://www.forbes.com/sites/brucelee/2020/03/30/reusing-n95-masks-against-covid-19-coronavirus-the-risks-and-options/#4a77b87cdf7e
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