Increase Respirator/N95 mask effectiveness
Began watching your videos a couple weeks ago, thanks for the no-spin info. I just registered on the site and wanted to share some info I came across a while back.
Not sure if you’ve covered this topic or have seen this, but it appears simple sodium chloride – yes, table salt – can increase the effectiveness of n95 and other fiber-type respirators against virus particles.
A saltwater solution can be applied and allowed to dry, which once in contact with a droplet or aerosol containing virus will mechanically destroy many of those virus particles. The paper does not go into great detail about the process (the original article mentioned that the researcher intended to patent the process), but there is a short section in the paper published about the preparation and application process. Also a theorized description of how/why this works is included:
Universal and reusable virus deactivation system for respiratory protection
Published Jan 4, 2017
It’s important to note that a wet mask is generally not as effective as a dry one, so it must be dried thoroughly. As for concentration, I believe the figure in the paper was 29% w/v sodium chloride and distilled water. A small amount of surfactant was also used to ensure even spread throughout the fibers.
This may, at the very least, allow for shorter rotation times for those of us with limited numbers of masks who cannot dispose of them after each use. Right now you should give them about 10 days (stored outside your home – they are biohazardous after use!) before a second use. Always use gloves when handling a used mask and do so carefully. Do not use disinfectant sprays or cleaners on them – it will damage them, reduce airflow and filtration ability. UV light is a good disinfectant, so maybe store them in a window in an outbuilding or shed, etc., as sunlight has plenty of UV. Don’t keep them in plastic bags or anywhere moisture can build or not escape, or where the humidity fluctuates. You may end up with a colony of bacteria or mold, fungi, etc. grow on them which could be much worse for you to inhale.
It is also important to properly fit your mask! I cannot stress this enough. Watch a short video of how to properly don, fit and doff your type of respirator. Even if you think you know how to do this correctly, search youtube and watch a video reminding you how to properly do it.
Remember, the point is to reduce your initial viral load. We may not all be able to prevent exposure in the long run, but your chances of serious illness are greatly reduced if your initial exposure is very low.
Yes, we found out about that study on 3/5. Here are the comment and discussion at the time:
gyrogearloose: Standard surgical masks stop 0% of H1N1 aerosole
I read this. Quick summary. Standard surgical mask material 0% effective at stopping H1N1 virus aerosols but after being treated with salt water became 100% effective. Article suggests other RNA viruses will performs similarly.
So an infected person wearing a standard surgical mask coughing will still disperse a cloud of infectious aerosole paertcles. Mask will only stop larger droplets that would fall quickly anyway. ( unless treated of course )
Rang my local health center ( oxford ) and spoke with receptionist about this. She said she would talk with the doctor in charge of their covid response. Got a call back that he would like to hear from me. I will get an insight into their preparedness and let you know.
nordicjack: regarding the salt coated surgical masks
They did demonstrate an increased affinity to hold virus aerosols. This was not a sanitizing action.. but I believe more of an ionic static charge barrier. This may increase the filtration of the mask. but, when you are talking about aerosols – u need a mask that seals completely – so its probably moot. are you a health worker? if not, a standard mask still reduces transmission from and to the wearer. for low concentration normally appearing low symptomatic contact with individuals.
dtrammel: Great video Sparky
Great video Sparky. I learned quite a bit. Seems the difference between the 3M pancake filters and the oblong canisters, is the canisters have a layer of activated charcoal and a HEPA filter layer.
He did do a good explanation on why even though the actual virus particles are in at 1.25 microns, and the N95 masks are rated just down to 3 microns, that the virus almost always piggie backs on a contaminate which will increase their size. Also that the N95 filters do more than just strict size filtration. They also depend on a variety of other methods, including the electo static which has been discussed re: salt solution soaking to increase mask efficiency.
Now one thing I’ve been wondering about. That is does the virus die when its dried out or does it go inactive?
I’d assumed that when you dry out the water droplets the virus’ enzyme shell cracks open and exposes the virus itself to the air, killing it but I’ve come across a couple of references to the virus going dormant, which might put a nick in the idea of storing soiled masks for 9 days and then reuse them.
Salt appears to add to the electro static effect, increase adhesion. I would’t say masks are ineffective. This method seems to be a method you could use to make DIY masks better.
Two things, yes you’d want to keep a watch on wet masks in plastic bags, but they are one of the few things you can seal which don’t block UV light like glass does.
Second, there are several studies and tests done using a variety of chemical disinfectants which will clean masks with little or no effect on mask structure or efficiency.
Take a look at the collections of comments I put together, posted here (Check the sanitation post). You can read thru them add see the methods.
Dear Chris and Adam,
Let me tell you on my first post: Great input you are giving us all. I gladly support your activities by premium membership since lately. Not to get a lot more from the paid section this moment but to support what you give out to the public for free.
Let me feel like a poor Covid19 virus now for a moment …. flying through the air from my source… trying to find another host to infect. I am getting dry… going to dye the longer I am in dry air and may be even in sunlight. Bad for me, ooh long distances…… ohhhh (distancing is the solution, be better in the outside air and so on)
Now MeTheVirus is coming close to another host to infect, have to go through a mask to get into the lung…. hard to get through… get in contact with something….it is salty, dries me, kills me, ouch, out.
I can well imagine salty environment is not good for viruses as the study tells us.
But should I soak my surgical mask with 30% salt, let it drye and put on my face? Or the N95 mask?
It will get wet and the salt get into contact with my skin, not so good.
May be I can isolate the mask from getting in contact, may be any plastic cover to attach on to the contact areas.
But colloidal silver has a good effect on bacteria and viruses as well. And I would not mind to have it on my skin compared to 30% salt solution. You may have it on your socks and other closings already my be without knowing.
So: soak you surgical mask with colloidal silver, with small amount of soap for good coating, may be in an ultrasonic bath. Let it dry.
Do you think this could enhance your surgical mask to help to get less amount of virus towards your lung?
what do you think?
The NanoMasks of the mid 2000s used silver nanoparticles to make them effective against virus. I have soaked our masks in CS.
just dropping liquid onto the mask (colloidal silver solution) does not work. The surface is hydrophobic and drops just drip down.
So please how do you turn your standard surgical mask into a silver loaded maks
The physical mechanism is pretty clear. The virus requires some level of water to be stable. Salt competes with the virus for available water…and therefore tends to deactivate/kill the virus. But getting the salt evenly dispersed in the mask seems tricky. I am sanitizing our masks with UV light.
I tried it with the 29%salt solution and a small amount of dish detergent as a wetting agent on a n95 mask, fully whetted by immersion and agitating till clearly fully wet.
Once dried the air resistance had increased so much I could only just breath at rest.
Their method delivered controlled volumes and a painstaking process.
My attempt ended up with too much salt in the mask blocking to much flow path.
Will be testing with a lower concentrations and report back with highest salt conc that leaves mask with sufficient air flow
Test with about half the salt and airflow good. now going to do math to check against paper’s salt levels per area.
solution I used today was 500ml water 68g salt and 2ml aprox of dish washing detergent.
The study on salt coated masks goes into the mechanism.
” When the salt-coated filter is exposed to virus aerosols, salt crystals below the aerosol droplet dissolve to increase osmotic pressure to virus. Due to evaporation, the salt concentration of the droplet significantly increases and reaches the solubility limit, leading to recrystallization of salt. As a consequence, virus particles are exposed to increasing osmotic pressure during the drying process and are physically damaged by crystallization. As shown in Fig. 3e,f, the superior advantage of physically destroying the virus adsorbed to the salt-coated PP filters through natural salt crystallization process was further confirmed in vivo.”
Trial of 14g of salt per 100ml water thoroughly soaking the entire mask, gave a mask that was free to breath through and matched the salt mass per area of the +600 micro liter experimental test level mask