Posted on 04/08/2020 12:48:45 PM PDT by nickcarraway
Since the coronavirus pandemic broke out, we have seen various versions of face masks people use to protect themselves against the virus, be it store-bought or homemade. But just how effective are these masks?
To find out, a Japanese chemistry professor compared three different types of face masks in a science experiment: a surgical mask, a homemade paper towel mask and a homemade cloth mask.
Dr Tomoaki Okuda, an associate professor of applied chemistry at Keio University, measured how well the three masks could block airborne particles using a Scanning Mobility Particle Sizer (SMPS).
To put it simply, the hose sucks the air in the room and measures its concentration of particles per cubic centimetre.
In his experiment, Okuda tuned the equipment to search for particles of virus size, which are estimated to be between 20 and 100 nanometers in diameter.
He wrapped the three masks around the opening of the hose and measured the number of air particles that were able to pass through. Here is a breakdown of his findings:
Surgical mask
With a store-bought surgical mask, the SMPS measured around 1,800 particles per cubic centimetre of air passing through. The results show that the mask has a collection efficiency of around 70 per cent, a high blockage rate for the estimated virus particle size.
Paper towel mask
Using three paper towels folded in half, Okuda tested a six-layer paper towel "mask". The SMPS measured around 1,000 particles per cubic centimetre of air passing through. With a collection efficiency of around 80 per cent, the paper towel mask appeared to be more effective in blocking out the estimated virus particle size compared to the surgical mask.
Cloth mask
A makeshift mask made out of a handkerchief folded thrice emulated the results of the surgical mask. The SMPS measured around 1,800 particles per cubic centimetre of air passing through, with a collection efficiency of around 70 per cent for the estimated virus particle size.
No mask
Additionally, Dr Okuda tested the hose without a mask covering it and the SMPS measured around 6,000 particles per cubic centimetre of air in the room that are between 10 and 150 nanometers in size.
So what does it mean? If we are near an infected person, there is potentially a lot of virus particles that we're breathing in.
Looking at the results, wearing a mask does seem to lower the chances of getting infected. Surprisingly, the mask fashioned from a handkerchief has the same effectiveness as a surgical mask, but even more so, who knew paper towels were the most effective?
However, regardless of which mask is the most effective, what's most important is to have good hygiene care and to wear masks properly. Here are also some tips on how to modify or wash your government-issued mask so that it can last longer.
but you can repurpose it by making a lovely origami flower or perhaps a crane..?
Cambridge U, UK, did a study as well.
British tea towel material was up there, but I believe a double layer of cotton t-shirt fabric was the best compromise weighted towards “breathability”.
Going the other way, a double layer of pillowcase fabric [linen?] offered more protection for slightly more effort in breathing.
“If they prevent an infected person from releasing viruses, why would they not prevent an uninfected person from taking in those viruses? “
The viral load in the air is very small so generally there is no virus to take in.
If you must maintain close contact with an infected person then you should were a qualified mask.
The surgeon doesn’t were the surgical mask for his protection, he wears it to protect his patient.
What about handy-wipes... Will they work?
Sounds good, but be sure your breathing tube has a secure connection to your portable ventilator - helps with the built-in cloaking device.
When I go to the store I wear a mask because it makes those around me feel better.
Necessity is the mother of invention? Or something?
“as anyone mathematician knows in elementary probability, the layering of several defense mechanisms multiply the protective effect.”
As every engineer knows, you don’t spend money trying to make very small risks slightly smaller.
I’d think Meth would kill everything..even the wearer.
“Going the other way, a double layer of pillowcase fabric [linen?] “
One cannot breathe through my wife’s pillowcases.
In the true story “The Hot Zone”, researchers into Ebola at Fort Detrick, MD were looking at viruses no larger than the period (.) at the end of a sentence...so I don’t believe any of this hokum...We’re being dazzled with stats which mean bonkers...I was told that wearing a “dust” mask wouldn’t trap the virus...if any old cloth can trap it, why can’t a “dust” mask? And I would say a solid material as in a dust mask should do it better! But what do I know? I don’t get paid for my opinion...
I would like to suggest.... the squad, Pelosi, Nadler, schumer, shitt, a large garbage bag around the head with a zip tie around the neck
They need to try one of those weird yellow dust cloths that can wipe all of the dust from a 2700 sq ft home.
—helps with the built-in cloaking device.
How did you know about that? I didn’t tell anyone. I think.
I sell coffee
Thought it was hilarious...
referring to the risk of infection. you want to make that smaller.
What about toilet paper?
“referring to the risk of infection. you want to make that smaller.”
Then you would keep every non-essential person in quarantine and every essential person. in full PPE! Duh ...
no. you decrease the probability of infection probablility by probability. i guess i’m not being clear. sorry.
say, three individual measures: mask, gloves, sanitizer gives you a 1/2 chance of infection. then using all three gives you. that’s what i mean, anyway.
1/2*1/2*1/2 = 1/8 = .125 = 12.5% probability of individual infection, instead of a 50% chance of infection.
the probability of non-infection 1-.125 increases to .875 or 87.5%. ok enough said.
Actually the test is bogus.
None of the masks made out of the material suggested will ever be snuggly worn on a face.
And unless they are sealed against the face, the more they trap, the harder it is to get air through them, and the more air will just come AROUND them.
THIS is why these masks are ineffective. Sure, clamping them down on a hose will limit what gets to the hose. But not if the hose can pull air around them.
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