5 ms·

This[0] article goes over recommendations for extended use, reuse, and risks. It also has a healthy list of references, some of which are by Fisher et al., the

This[0] article goes over recommendations for extended use, reuse, and risks. It also has a healthy list of references, some of which are by Fisher et al., the author of the paper you linked. Most masks have a metal tab bending over the bridge of the nose, as well as metal staples for the elastic bands, which would prevent you from microwaving. Cartridge type filters would work though. [0]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3373043/#!po=12.5000 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3373043/#!po=12...

doodlebugging 7y ago
I had considered the metal parts of the mask to be a potential problem. In the worst case scenario it should be relatively simple for mask owners to remove the metal tab from the nose and the staples holding the elastic bands before microwaving. Once they are done in the microwave the bands could be stapled in place with your ordinary stapler and the band reattached with hot glue. Those who have a needle and thread could also stitch a sleeve onto the nose piece that is open at one end and just reinsert the metal nose piece once it is out of the microwave. The thin metal should withstand several bend cycles before needing to be replaced and it can be replaced with any thin aluminum strip which one could obtain from lots of places around the house or at the hardware store. The bands and straps could be washed in ordinary soap to sterilize them before reuse. Just thinking outside the box here. What do you think?
- mattkrause 7y ago
  You probably want to avoid manipulating the mask a lot, both because it may be contaminated and to avoid punctures.
  - doodlebugging 7y ago
    I agree that the mask could be contaminated. In fact, I would hope that the person wearing the mask has a good reason to wear it, either someone in their household is sick and they are protecting themselves or they are sick and they are protecting everyone else who is home with them. I think it is a bad idea for everyone to wear a mask when there is no threat to their health. With people furloughed home it is likely that many of us can avoid contact with an infected person and therefore we don't need masks. But if the user has paid close enough attention these last few weeks, then they are probably already washing hands anyway so as long as they wash up after putting the mask in the microwave and before they touch their face they should be good. If the mask is punctured that creates a much larger path for droplets to get behind the mask or if the user is the infected one, to get past the mask into the clean air on the other side. To mitigate that situation, there is no reason that I can see where coating the puncture with elmer's glue, hot glue, etc doesn't solve that issue. Bending the mask will probably create permeability that could allow larger particles to pass anyway. The plastic filaments they talk about are not likely to hold up to much flexing and it is a decrease in the tortuosity of the path through the media that creates the risk. Therefore, breakage along clearly defined planes creates an easy path through the media even if the mask is perfectly fitted to spec. I think bending the mask is the easiest way to send it out of spec so like you say, manipulating the mask creates a situation where it may no longer be effective against the particles sizes that it should protect against.
    - paulmd 7y ago
      While I suppose it’s an interesting academic discussion, frankly the idea of being able to safely contain an aerosolized upper respiratory disease at home is ludicrous to begin with, so it doesn’t really matter. The simple truth of the matter is that if you are in a home or apartment with an infected person, and you remain present during their period of high viral shedding, you’re practically certain to contract it as well. You don’t have a negative pressure containment room, your home furnace is going to drag it all over the house. Normal airflow as you open the door will probably drag it out. It’s perfectly valid to stay and care for grandpa, just don’t have any illusions that you’re not going to get it as well. You 100% will. Doctors who are trained in cleanliness and with access to real, non-makeshift gear are getting it. That’s fine if you’re not a senior yourself. Severe reactions are fairly rare for anyone under 60 or so. And it can’t really be helped without abandoning grandpa.
      - doodlebugging 7y ago
        I am going to use recent personal experience to disagree with your conclusion that uninfected people in a house with someone who is infected cannot protect themselves and will end up sick. This past December, in the week before Christmas, my wife had surgery that required an overnight stay. She was released with instructions to avoid laughing, coughing, no physical activity, etc. for several weeks. A couple days after she was home our son came down with an infection that turned into a deep, dry, raspy cough with sudden fever over 102*F. Since she needed to avoid any sort of infection and he was getting worse by the hour I took him to ER where he had a test for flu since people at his school had been down with it in the weeks prior. The ER doctor told us it was a viral infection but the flu test was negative meaning that we either got there before there was enough viral material for a positive test or that it was something else causing it besides flu. It became my job to keep his infection from spreading to my wife. To manage that I used sanitation instructions from my sister, a nurse, and I kept him isolated in his bedroom and my wife in our bedroom. I prepared all meals, etc. and cleaned the house, etc. I slept in a spare bedroom in case I was infected. I bought some cheap face masks, not hospital grade, just over-the-ear masks and made sure that she wore one every time she left her room and he wore one every time he left his room. I also wore one every time he left his room. Once he returned to his room I went along behind him and wiped every knob, switch, flat surface, etc that he could've contacted and put his used glasses and utensils in the dishwasher. Then I washed my own hands. My son's fever broke after 4 days on Motrin and his cough went away too. My wife never got sick and neither did I. We were all in the same house sharing the same air on days when the heater ran regularly due to a strong cold front. No one wore a mask all the time. We wore them only when we had the opportunity to have contact with each other. When the stories started breaking in China about this, I started following it all here on HN. I understood the challenges they would face having just faced similar challenges myself. I found myself with part of a container of lysol wipes, a few cheap face masks that hadn't been used, some hand sanitizer for each bedroom, and the knowledge that one could beat something like this if they were diligent. I realize that this is just my story but it is all true. Isolating the infected person, using PPE, sanitizing everything diligently can prevent everyone in the house from being infected if someone in your family does come down with an airborne infection. My house is cluttered and disinfecting was potentially a chore but I made it easier by following each person along and watching carefully everything that they did while they were out "in public". Once they were isolated, I retraced their steps wiping everything down. I hope you don't have to share my experience but you can rest easier knowing that there is hope.
- tim333 7y ago
  Apparently salt on the mask kills viruses https://www.sciencedaily.com/releases/2017/01/170105160228.htm https://www.sciencedaily.com/releases/2017/01/170105160228.h... https://www.businessinsider.com/mask-coated-in-salt-neutralizes-viruses-like-coronavirus-2020-2 https://www.businessinsider.com/mask-coated-in-salt-neutrali... I was going to DIY. Soak in brine then dry the thing.
  - Engineering-MD 7y ago
    I believe it also recommends the addition of a surfactant to make small crystals and a more even coating
    - doodlebugging 7y ago
      I read the same thing. Glad to see others investigating their options. I'm not sure a DIYer could accomplish this without compromising the filter media unless there were kits available or a crystal clear guide for the task. I realize that you can just wash the mask to remove the salt and surfactant and in the process any pathogens will be killed by the salt and soap. However, if you have to wait on this to dry between uses since the washing will fill some percentage of the pore spaces with water then you haven't accomplished as much as you could have if you had simply microwaved the mask in a boil-in bag allowing the steam to do the same work. As a bonus, people already know how to use microwaves and most have them at home. I'm not trying to say that salt and surfactant doesn't work, only to say that this is better accomplished in a controlled environment with equipment that can insure that crystal size is controlled and filter media is relatively unaffected.
  - doodlebugging 7y ago
    I read about this option. The potential problem that I see is that coating the mask with salt or another substance, especially if part of a DIY project, is likely to leave you with a mask that is unusable since you have no way to control salt crystal size, nucleation points, etc. The crystals will inevitably grow on the treated surface and block the filter media so that you start with an N95 rated mask and end up with an N99 or higher rated mask that can only be used for a few minutes before it leaves the user gasping for breath. Preserving the filter ability should be the goal in the sterilization process. I don't see a way to accomplish that without specialized equipment that allows the user to limit crystal size and nucleation sites. That is why microwaving or UV sterilization seem the most viable to me. UV sterilizers require the user to follow specific guidelines to avoid health negative consequences and it seems unlikely that everyone could or would take steps to protect themselves from the UV damage. Microwaves are nearly ubiquitous, though I personally don't own one and haven't since I had my wife get rid of ours once our son was done with bottle feeding. People know how to follow directions for using microwaves. It just seems easier to me to accomplish the objective with something that is a common or easily obtained household item that people are already familiar with.
doodlebugging 7y ago
BTW, I think you hit the mother lode on links about potential decontamination methods. I need to read some of this for future reference. Thanks!
roel_v 7y ago
"as well as metal staples for the elastic bands, which would prevent you from microwaving" My microwave works fine with metal inside. Would only be a problem for some people.
- doodlebugging 7y ago
  Thanks for this information. Very useful.

doodlebugging 7y ago

I had considered the metal parts of the mask to be a potential problem. In the worst case scenario it should be relatively simple for mask owners to remove the metal tab from the nose and the staples holding the elastic bands before microwaving. Once they are done in the microwave the bands could be stapled in place with your ordinary stapler and the band reattached with hot glue. Those who have a needle and thread could also stitch a sleeve onto the nose piece that is open at one end and just reinsert the metal nose piece once it is out of the microwave. The thin metal should withstand several bend cycles before needing to be replaced and it can be replaced with any thin aluminum strip which one could obtain from lots of places around the house or at the hardware store. The bands and straps could be washed in ordinary soap to sterilize them before reuse. Just thinking outside the box here. What do you think?

mattkrause 7y ago
You probably want to avoid manipulating the mask a lot, both because it may be contaminated and to avoid punctures.
- doodlebugging 7y ago
  I agree that the mask could be contaminated. In fact, I would hope that the person wearing the mask has a good reason to wear it, either someone in their household is sick and they are protecting themselves or they are sick and they are protecting everyone else who is home with them. I think it is a bad idea for everyone to wear a mask when there is no threat to their health. With people furloughed home it is likely that many of us can avoid contact with an infected person and therefore we don't need masks. But if the user has paid close enough attention these last few weeks, then they are probably already washing hands anyway so as long as they wash up after putting the mask in the microwave and before they touch their face they should be good. If the mask is punctured that creates a much larger path for droplets to get behind the mask or if the user is the infected one, to get past the mask into the clean air on the other side. To mitigate that situation, there is no reason that I can see where coating the puncture with elmer's glue, hot glue, etc doesn't solve that issue. Bending the mask will probably create permeability that could allow larger particles to pass anyway. The plastic filaments they talk about are not likely to hold up to much flexing and it is a decrease in the tortuosity of the path through the media that creates the risk. Therefore, breakage along clearly defined planes creates an easy path through the media even if the mask is perfectly fitted to spec. I think bending the mask is the easiest way to send it out of spec so like you say, manipulating the mask creates a situation where it may no longer be effective against the particles sizes that it should protect against.
  - paulmd 7y ago
    While I suppose it’s an interesting academic discussion, frankly the idea of being able to safely contain an aerosolized upper respiratory disease at home is ludicrous to begin with, so it doesn’t really matter. The simple truth of the matter is that if you are in a home or apartment with an infected person, and you remain present during their period of high viral shedding, you’re practically certain to contract it as well. You don’t have a negative pressure containment room, your home furnace is going to drag it all over the house. Normal airflow as you open the door will probably drag it out. It’s perfectly valid to stay and care for grandpa, just don’t have any illusions that you’re not going to get it as well. You 100% will. Doctors who are trained in cleanliness and with access to real, non-makeshift gear are getting it. That’s fine if you’re not a senior yourself. Severe reactions are fairly rare for anyone under 60 or so. And it can’t really be helped without abandoning grandpa.
    - doodlebugging 7y ago
      I am going to use recent personal experience to disagree with your conclusion that uninfected people in a house with someone who is infected cannot protect themselves and will end up sick. This past December, in the week before Christmas, my wife had surgery that required an overnight stay. She was released with instructions to avoid laughing, coughing, no physical activity, etc. for several weeks. A couple days after she was home our son came down with an infection that turned into a deep, dry, raspy cough with sudden fever over 102*F. Since she needed to avoid any sort of infection and he was getting worse by the hour I took him to ER where he had a test for flu since people at his school had been down with it in the weeks prior. The ER doctor told us it was a viral infection but the flu test was negative meaning that we either got there before there was enough viral material for a positive test or that it was something else causing it besides flu. It became my job to keep his infection from spreading to my wife. To manage that I used sanitation instructions from my sister, a nurse, and I kept him isolated in his bedroom and my wife in our bedroom. I prepared all meals, etc. and cleaned the house, etc. I slept in a spare bedroom in case I was infected. I bought some cheap face masks, not hospital grade, just over-the-ear masks and made sure that she wore one every time she left her room and he wore one every time he left his room. I also wore one every time he left his room. Once he returned to his room I went along behind him and wiped every knob, switch, flat surface, etc that he could've contacted and put his used glasses and utensils in the dishwasher. Then I washed my own hands. My son's fever broke after 4 days on Motrin and his cough went away too. My wife never got sick and neither did I. We were all in the same house sharing the same air on days when the heater ran regularly due to a strong cold front. No one wore a mask all the time. We wore them only when we had the opportunity to have contact with each other. When the stories started breaking in China about this, I started following it all here on HN. I understood the challenges they would face having just faced similar challenges myself. I found myself with part of a container of lysol wipes, a few cheap face masks that hadn't been used, some hand sanitizer for each bedroom, and the knowledge that one could beat something like this if they were diligent. I realize that this is just my story but it is all true. Isolating the infected person, using PPE, sanitizing everything diligently can prevent everyone in the house from being infected if someone in your family does come down with an airborne infection. My house is cluttered and disinfecting was potentially a chore but I made it easier by following each person along and watching carefully everything that they did while they were out "in public". Once they were isolated, I retraced their steps wiping everything down. I hope you don't have to share my experience but you can rest easier knowing that there is hope.
tim333 7y ago
Apparently salt on the mask kills viruses https://www.sciencedaily.com/releases/2017/01/170105160228.htm https://www.sciencedaily.com/releases/2017/01/170105160228.h... https://www.businessinsider.com/mask-coated-in-salt-neutralizes-viruses-like-coronavirus-2020-2 https://www.businessinsider.com/mask-coated-in-salt-neutrali... I was going to DIY. Soak in brine then dry the thing.
- Engineering-MD 7y ago
  I believe it also recommends the addition of a surfactant to make small crystals and a more even coating
  - doodlebugging 7y ago
    I read the same thing. Glad to see others investigating their options. I'm not sure a DIYer could accomplish this without compromising the filter media unless there were kits available or a crystal clear guide for the task. I realize that you can just wash the mask to remove the salt and surfactant and in the process any pathogens will be killed by the salt and soap. However, if you have to wait on this to dry between uses since the washing will fill some percentage of the pore spaces with water then you haven't accomplished as much as you could have if you had simply microwaved the mask in a boil-in bag allowing the steam to do the same work. As a bonus, people already know how to use microwaves and most have them at home. I'm not trying to say that salt and surfactant doesn't work, only to say that this is better accomplished in a controlled environment with equipment that can insure that crystal size is controlled and filter media is relatively unaffected.
- doodlebugging 7y ago
  I read about this option. The potential problem that I see is that coating the mask with salt or another substance, especially if part of a DIY project, is likely to leave you with a mask that is unusable since you have no way to control salt crystal size, nucleation points, etc. The crystals will inevitably grow on the treated surface and block the filter media so that you start with an N95 rated mask and end up with an N99 or higher rated mask that can only be used for a few minutes before it leaves the user gasping for breath. Preserving the filter ability should be the goal in the sterilization process. I don't see a way to accomplish that without specialized equipment that allows the user to limit crystal size and nucleation sites. That is why microwaving or UV sterilization seem the most viable to me. UV sterilizers require the user to follow specific guidelines to avoid health negative consequences and it seems unlikely that everyone could or would take steps to protect themselves from the UV damage. Microwaves are nearly ubiquitous, though I personally don't own one and haven't since I had my wife get rid of ours once our son was done with bottle feeding. People know how to follow directions for using microwaves. It just seems easier to me to accomplish the objective with something that is a common or easily obtained household item that people are already familiar with.

doodlebugging 7y ago

BTW, I think you hit the mother lode on links about potential decontamination methods. I need to read some of this for future reference. Thanks!

roel_v 7y ago

"as well as metal staples for the elastic bands, which would prevent you from microwaving" My microwave works fine with metal inside. Would only be a problem for some people.

doodlebugging 7y ago
Thanks for this information. Very useful.