If you know any healthcare workers (doctors or nurses), have them checkout https://www.n95decon.org/ to follow the latest on sterilizing face masks.
N95 masks should be reserved for HCWs as there is a major shortage. Most people should just wear nonmedical fabric or homemade masks, but everyone should wear some kind of mask when out and near other people. See https://shouldiwearafacemask.com
- If it is true that soap kills the virus by breaking up it's outer lipid layer, does that mean soaps and degreasing agents and coatings may also kill it on surfaces like clear visors, gloves and other fabrics?
- While N95 (non oil particulate) masks are considered sufficient, and P and R 95+ (oil particulate filters) are not considered necessary - are those oil particulate filters also considered sufficient?
- can folded, oil-absorbant paper shop cloths provide more protection than cut-up t-shirts and regular cotton?
This is very useful, I have made a 3 layer Qualitative Filter based face mask with middle layer soaked in brine solution for possible virus deactivation[1].
With more governments officially recommending DIY face masks for public, so that proper N95 masks can be left to the health care workers; I would love to get my mask scientifically tested.
I also wonder how such re-use of a mask combined with more durable N99 masks that are ordinarily rated at hundreds of hours for the filter (compared to 8 hours for your average N95 mask) could be used as a more permanent mask for households if only used occasionally when going to get groceries for example.
There's been a lot of press about people making their own face masks out of fabric and it got me thinking about copper-impregnated fabric (if you watch enough late-night TV you'll have seen those CopperFit infomercials). Copper itself has antimicrobial properties (studies say SARS-CoV-2 only lives 4 hours on copper), but does anyone know if there is enough copper content in those fabrics to make them a better fabric for face masks than cotton?
>Copper itself has antimicrobial properties (studies say SARS-CoV-2 only lives 4 hours on copper), but does anyone know if there is enough copper content in those fabrics to make them a better fabric for face masks than cotton?
I think you answered your own question. Viruses only get killed if they're on copper for 4 hours, so it might be useful if you wanted a self-disinfecting mask, but if the material itself doesn't filter properly the antimicrobial properties of copper doesn't matter because the viruses fly straight through and aren't affected by the copper.
Right. I should've phrased the question as: is the copper content sufficiently high enough to make a significant impact on the disinfection rate compared to just say, cotton? Obviously it won't make a difference (I think?) during wear, but if it the virus dies quicker than on cotton then one could potentially disinfect the mask less frequently.
Thanks, that was pretty informative. We have a bunch of one time use standard surgical masks at home. I wonder if I can just put them in a bag of salt after single use.
What if you dip in isopropyl alcohol then dry, sounds safer than bleach and less destructive for the fabric. Bleach is chlorine you would have to wash it afterwards.
that is the N95 masks made of blown polypropylene, not cloth masks made at home (for example two layers of teatowel is quite an effective filter apparently)
What if I have X masks and rotate their usage without any cleaning at all. Would this allow the virus to die naturally without the need to clean the mask?
Yes, this will work and is current healthcare professional practice in many places. It will take a few days, though, so people usually line up like 5-6 and then rotate through those.
If you can heat the masks that's cool, too, but then you have to make sure you don't damage the elastic or seal. Waiting will work.
according to the OP paper, that's an unproven strategy. i can't find anything else supporting it in the literature linked by that paper either. so the real answer is that we don't know.
however, while it appears to be unproven, given what we know about how long the virus survives on different materials, i would say that it is probable that leaving a mask aside in a dry spot for a week or so is effective at ensuring there are no viable viral particles remaining on the mask.
as long as we're using unproven decontamination methods, i'd say to also leave the external surface of the mask in direct sunshine for a few hours too.
as the OP paper notes, sun bleaching / UVR does degrade the quality of the filtration by a small amount (around 1.5% if i recall) but it's also effective at destroying viral particles in a short period.
Tech Ingredients did a fantastic video on the subject recently, I love everything from this guy and the recent series in response to COVID-19 is great stuff.
After reading the article there is an important insight I did not know of and clearly neither did Tech Ingredients as they demonstrate use of alcohol.
from the article
"the FE (filtration efficiency) of these masks is influenced by the electrostatic charges embedded within the fibers of the filtration layer(s) in the interior part of the masks."
"... using alcohol will erase the charges. However, exposing the masks to air at elevated temperatures such as 70℃ for 30 minutes allows the charges to be retained."
"He does not give any advice on the performance of the re-sterilized N95 or mask against the virus."
So... we want the attention but not the risk of you taking our advice. If you have something of interest, why haven't you contacted people whose lives you could save?
N95 masks should be reserved for HCWs as there is a major shortage. Most people should just wear nonmedical fabric or homemade masks, but everyone should wear some kind of mask when out and near other people. See https://shouldiwearafacemask.com