Posted on 03/10/2021 9:43:38 AM PST by Red Badger
Cotton flannel (left) and polyester (right). (E.P. Vicenzi/Smithsonian Museum/NIST)
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While some still quibble over wearing masks a year into the pandemic, scientists have gotten on with working out exactly what strategy is best - and cotton face masks just received another tick of approval.
Various studies have tested different material combinations and health authorities such as the World Health Organization and the CDC recommend cloth masks for the general public, based on their conclusions. But some of these studies overlooked an important real-world factor - these face covering fabrics end up damp from our breath.
Now, a team of researchers has tested mask materials under high humidity conditions that mimic the air expelled from our mouths.
"This new study shows that cotton fabrics actually perform better in masks than we thought," said material scientist Christopher Zangmeister from the US National Institute of Standards and Technology (NIST).
Zangmeister and colleagues tested nine different types of cotton and six types of synthetic fibers including polyester and rayon in 99 percent humidity (about how humid our breath is) and 55 percent humidity.
This resulted in a remarkably visible difference in the performance of cotton.
Cotton masks become better filters when they absorb the moisture from your breath, making them even better at slowing COVID-19 than we thought: https://t.co/qbGtnC4a42 pic.twitter.com/91hNVIvlTX
— National Institute of Standards and Technology (@NIST) March 9, 2021 While synthetic fabrics, which also performed poorly compared to dry cotton, did not change performance under humid conditions, cotton fabrics increased their ability to capture particles by 33 percent.
The researchers used variously sized particles of salt as a test substitute for virus-transporting droplet and aerosol particles,and these appeared to absorb some of the moisture trapped by the water-attracting cotton fibers. The particles swell in volume, which makes it harder for them to pass through the fabric uninhibited.
Synthetic fibers, however, repel water, thus not creating the humid environment within the mask itself for this inhibition to happen. There was also no change in medical masks - but they are designed to work at high levels in all conditions (equivalent levels to cotton).
The best-performing type of cotton was cotton flannel, according to the results.
Microscopic images of the materials reveal a stark difference in structure - an orderly weave pattern in synthetic polyester compared to the chaotic network of crisscrossing fibers that give flannel its soft-to-touch feel.
NIST researchers believe this mess of fibers is what increases the chance airborne particles passing through the mask will collide and stick to the fabric.
However, all this doesn't mean wet masks are better: If your mask gets wet, it should be replaced. The amount of liquid present in the masks in these humid conditions amounts only to a few drops, which doesn't alter the material's breathability - the team found air pressure on both sides of the fabric remained relatively similar.
This is great news from an environmental perspective too. With mounting waste from disposable surgical masks that shed microplastics, it's comforting to know there's a safe, reusable option.
Research suggests owning a bunch of reusable masks that can be machine-washed together is the most eco-friendly option to keep you and your loved ones safe.
While the team says more research is required to fully appreciate the interactions between masks, humidity, and aerosol particle transmission, their study has contributed to the first international standards for fabric masks meant to slow the spread of COVID-19, recently released by the standards-developing organization ASTM International.
"To understand how these materials perform in the real world we need to study them under realistic conditions," Zangmeister concluded.
This research was published in ACS Applied Nano Materials.
Stop wearing masks. Just stop it. Masks have nothing to do with spreading “covid”.
Best solution: get two or three of them, wrap them around your mouth and nose really tight, and then add some plastic wrap to be really safe.
No mention whether the things work.
All I know is that nearly everyone who has gotten covid over the last feral months have all pretty much worn masks. 🤔
IF one were inclined to actually wear a mask. Stickin’ with the shield that mounts to my glasses frames when necessary.
We used to understand the fact that you cannot stop the movement of viruses. There is only one way, and that is immunity, which we would’ve hit long ago if we had acted like grown ups.....
Me too. And, after the initial BS a year ago, about 6 weeks after that we started doing our normal acticities except for wearing face shields that mount to your eyeware. We’ve been exposed to hundreds of people we don’t live with and seems so far we’re okay. Some of our acquaintances have gotten it despite “following the rules”. Some more severly than others. Shots? Nope. Still 300+ million folks in the U.S. don’t have it.
I prefer slave harvested cotton for all my masks, sure its more expensive, but the quality of hand picked cotton cant be beat.
That has been what I have seen also. Of the two people I know who got CCPVirus, they were mask wearing, social distancing, etc. before it was mandated.
I just put up a chain link fence to keep out mosquitos.
#MalariaProofing
Better put up another one, just in case! </Falsi>
My Lord, are we spending money on this crap.
A nice picket fence, maybe?
Those pictures show a black & white bar scale at the bottom scaled in 250 uM (micrometers) units. Consider a virus is 5 to 10 uM. That’s 25 to 50 times smaller than one of the units in the scale.
“Materials that suffocate you more in use are better for you.”
Yep- in most states masks are mandatory- and until recently- covid cases were still as bad as a year ago, per day- this proves that masks were not working. 1000’s who wore masks, did the social distancing, washing hands etc were still getting it every day-
I think the scientific evidence is showing they don’t make a difference- Florida, which hasn’t mandated masks for awhile now, should be much higher covid cases than rest of country, but they arent.
NIST is a very legitimate lab that practices hard science.
With that being said, they state clearly that this design is “more likely to catch the virus.” (Paraphrased) I would accept that from NIST as I hold them in very high regard.
Here is the quote - “NIST researchers believe this mess of fibers is what increases the chance airborne particles passing through the mask will collide and stick to the fabric.”
What is the “increased chance”? Keep in mind that these materials are tested in ideal situations.
It is a simple fact that masks do not prevent airborne virus transmission. Even assuming the mask is of proper design, is worn properly, and it is clean and in good condition, it will only catch some amount of the virus. The mesh size or filter size is far larger than the virus itself and this is the problem they cannot overcome.
Do they provide some small level of protection?
Ask yourself if you would have sex using a condom and wanting to avoid a pregnancy IF the failure rate was 1 in 2 for example. I am pretty convinced after lots of reading and some experience that 50% reduction is optimistic, but we do not know.
They are a risks reduction measure that may not be very effective based on real world data.
Masks also have a downside in that they provide people with a false sense of confidence and as many have pointed out, even assuming you have a good seal and airflow, they tend to be used for days (not minutes as intended) so they get dirty and may collect the virus providing other pathways. This “collection” (not to mention the thriving bacterial farm on your face) might pose a larger risks.
The cheaper masks we have seen also lose their effectiveness in a short time. They are disposable for a reason. When I worked in a surgical suite many years ago you NEVER kept the same mask. They were “disposable” and you disposed of them frequently.
It is a simple fact that masking was never accepted as a protective measure for an airborne virus prior to Covid. In a hospital setting, used as PPE, it was supposed to avoid airborne liquid droplets (much like eye protection) from saliva and blood. Prior to Covid, positive pressure respirators or respirators were recommended to protect against airborne viruses and N95 masks were not considered or used for protection from airborne viruses like Covid. This is why airborne viruses are so scary!
The science was settled before “orange man bad”. I am fine if people want to wear a mask. I wear one when businesses, my employer, or other people request it of me. Fine and I don’t make any fuss about it. However, too many people issuing mandates to us have oversold the protection of these masks and put too much blind faith in them.
Don’t believe me? Look at the real numbers of people “wearing masks” who have been infected. The available data does not support the claims that one mask, two mask, or more will stop you from getting the virus. The few studies that I have seen show little effect.
The virus is very small (all viruses are) and the best analogy might be that you are hiding behind a chain linked fence and someone is shooting a BB gun at you. You are going to get hit.
Is this in honor of Dr. Fraudci’s one year anniversary of telling the public “MASKS DON’T WORK.”? Did Dr. Fraudci lie to the public last year when he stated masks were ineffective in stopping the spread of the virus or is he lying now? ... asking for a friend.
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