Glorthan wrote:"The least expensive cloth masks removed just 39-65% of standard particles of 30-, 100-, and 500-nanometers, and 1- and 2.5-micrometers"
https://www.sciencedaily.com/releases/2 ... 114227.htm"The 65% total incombustible content required for intakes was based on the measured size of coal dust found in mines during the 1920’s and the amount of rock dust required to inert that size of coal in full-scale experimental mine tests (Nagy, 1981). The term “mine size coal” was adopted in about 1925 and refers to coal dust, all of which passes a U.S. Standard No.20 sieve (850 μm) and contains 20% minus 200-mesh (75 μm). The justification for adopting it is given in Bureau of Mines Technical Paper (TP) 464 (Rice and Greenwald, 1929). In the 1920’s, representative dust samples were collected from mine passageways that were not rock-dusted, and then they were sized using sieves. TP 464 states that these coal dust samples collected from the mine floors had 5% to 40% of the material less than 200 mesh. TP 464 further indicates says that the values were weighted as far as possible, and for 80% of the mines, the final values ranged from 15% to 25% through 200 mesh."
https://www.cdc.gov/niosh/mining/UserFi ... /cdpss.pdfSo cheap cloth masks are ~50% effective at blocking particles at under 2.5μm, and better as the size increases. 80% of particles under 850 μm are bigger than 75 μm.
A cloth mask blocking 90% of coal dust damage seems a very conservative estimate.
It is ironic that you are defending this idea by posting a paper which has in the title that cloth provides POOR PROTECTION.
"our results suggest that cloth masks are
only marginally beneficial in protecting individuals from particles of 2.5 μm."
In addition, they don't really specify what these masks were, other than that they were bought from some random street vendors in Kathmandu.
These masks are probably industrially produced with cool modern mechanized looms, and something that hearthlings couldn't produce.
Cloth made by hearthlings is probably of lesser density and poorer quality, not giving as good protection.
And the second paper is related to
modern mines with
modern mining methods, and addresses the
explosiveness and how particle size affect that. Which is not related to this issue at all.
Perhaps we should add chance for explosions while mining coal as well, is that what you are suggesting by linking this?
Black lung is caused by particles smaller than 5-10µm in size, <2.5µm being the most dangerous. Larger particle sizes than that won't get deep enough in your lungs without any mask anyway.
There are other problems with masks too. The larger dust builds up in the mask over time, making breathing difficult.
And wrapping the mask tightly while still not preventing the breathing too much is difficult, which is maybe one of the biggest reasons why your suggestion is bad.
Mining is hard work, you sweat, and it's very very moist in caves. Wearing even thin layer of cloth in front of your face is really not a good idea, you will soon faint and struggle to breath.
Your estimate of 90% is ridiculous, even the papers that you linked didn't claim prevention of that level.
If there was 90% prevention by using some simple piece of cloth, black lung as a disease wouldn't exist.
In addition your paper used some mannequin doll to do these experiments, which doesn't take into account how the mask leaks stuff because of how actual human face works.
https://oem.bmj.com/content/oemed/75/6/446.full.pdf In here, some actual 2.5µm filters were used, but what I want to point out in this is how much leakage there was with especially the more-primitive-looking masks when they used actual volunteers for testing.
If the bandit mask was to provide some protection, it would have to be very, very minor protection, like 0-10%
at most. Even that is a bit questionable.
You may as well delete the whole wound instead of adding some shitty and 1000% unrealistic mechanic like this prevent it.
tldr: ur defending of this idea sucks, stop linking papers if you dont even read them
shitposter
Not agreeing with you = shitposting, nice logic
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