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THE EFFICACY OF MASKS PLEASE, RT AND SHARE!!
General Overview:
Wearing a mask does little to protect you. However, wearing a mask helps to protect other individuals around you by helping to prevent the spray of respiratory droplets.
Studies show that homemade single-layer masks have ONE-THIRD the overall effectiveness of medical grade masks. That’s significant!!
Medical grade masks have 3 layers of synthetic non-woven materials.
Medical grade masks have 3 layers of synthetic non-woven materials.
The middle layer is a microfibre layer that filters out MOST micro-particles. NOT ALL micro-particles are filtered out!
Can you guess which micro particles are not filtered out?
Filtration Effectiveness:
Can you guess which micro particles are not filtered out?
Filtration Effectiveness:
Studies show that filtration effectiveness, for homemade cloth masks, range from 3%-95%. This is a very wide range!!
Particle Penetration:
Medical grade masks are shown to be much more effective at preventing the incidence of particle penetration (44%)
Particle Penetration:
Medical grade masks are shown to be much more effective at preventing the incidence of particle penetration (44%)
compared to homemade 2-layer cloth masks (97%).
Again, this is a significant reduction in the efficacy of cloth masks!
Also, there is a difference in particle penetration for a woven versus a nonwoven mask.
Again, this is a significant reduction in the efficacy of cloth masks!
Also, there is a difference in particle penetration for a woven versus a nonwoven mask.
The incidence of particle penetration, for a nonwoven mask, is significantly lower compared to cotton masks. Nonwoven masks show a mean particle penetration of 53% vs 70% for cotton masks.
This explains why the CDC recommends a multilayer mask made out of 100% nonwoven cotton.
This explains why the CDC recommends a multilayer mask made out of 100% nonwoven cotton.
It provides > bacteria filtration AND air permeability!
Next, let’s take a look at the mean particle penetration for cloth handkerchiefs. I think we’ve all seen those around, right?
Cloth handkerchiefs (even up to 4 layers thick) have shown a mean particle penetration of 87%.
Next, let’s take a look at the mean particle penetration for cloth handkerchiefs. I think we’ve all seen those around, right?
Cloth handkerchiefs (even up to 4 layers thick) have shown a mean particle penetration of 87%.
Recap:
Not including medical grade masks, non-woven, 2 or 3 layered cloth masks are most effective in reducing the incidence of particle penetration. Woven and single layered fabric masks are significantly less effective and handkerchiefs are the least effective!
Not including medical grade masks, non-woven, 2 or 3 layered cloth masks are most effective in reducing the incidence of particle penetration. Woven and single layered fabric masks are significantly less effective and handkerchiefs are the least effective!
It is also worth noting that studies show a significantly higher risk of contracting influenza among individuals using cloth masks in comparison to individuals using medical grade masks.
Below is a link to the journal. Please, take a look for more information.
Below is a link to the journal. Please, take a look for more information.
Respiratory Exhalation:
0 u (micron) = 0.00 um (micrometer)
1 u (micron) = 1.00 um (micrometer)
The size of the droplet determines how far it travels from the infected person. Larger droplets fall quicker than they evaporate. Smaller droplets evaporate quicker than they fall
0 u (micron) = 0.00 um (micrometer)
1 u (micron) = 1.00 um (micrometer)
The size of the droplet determines how far it travels from the infected person. Larger droplets fall quicker than they evaporate. Smaller droplets evaporate quicker than they fall
Airflow is also important to consider when determining the distance at which the droplets travel. Without airflow, droplets do not travel as far.
Based on the American Journal of Respiratory and Critical Care Medicine, large respiratory droplets can travel roughly 6 feet horizontally when a person coughs or sneezes.
In contrast to large droplets, small droplets can travel 13-20 ft vertically in the air.
In contrast to large droplets, small droplets can travel 13-20 ft vertically in the air.
The diameter size of respiratory droplets also determine the speed at which these droplets fall.
For example, droplets 100 um in diameter may take 10 seconds to fall whereas droplets 10 um in diameter may take up to 17 minutes to fall to the floor.
For example, droplets 100 um in diameter may take 10 seconds to fall whereas droplets 10 um in diameter may take up to 17 minutes to fall to the floor.
https://www.atsjournals.org/doi/pdf/10.1164/rccm.202004-1263PP
Speaking of size, let’s discuss the size of coronavirus particles.
Speaking of size, let’s discuss the size of coronavirus particles.
According to Mayo Clinic, a coronavirus particle is about 0.12 u (microns) in size. Some coronavirus particles were found to be as small as 0.065 u (microns).
N95 masks protect individuals from particles that are larger or equal to 0.1 u (microns) in size.
N95 masks protect individuals from particles that are larger or equal to 0.1 u (microns) in size.
If every person had access to a properly fitted N95 mask, we would be in business! 
Knowing that the coronavirus is measured at about 0.12 u (microns) some fabrics provide much less protection against the transmission of a coronavirus.
Knowing that the coronavirus is measured at about 0.12 u (microns) some fabrics provide much less protection against the transmission of a coronavirus.
Based on a study that was done, in 2010, by the National Institute for Occupational Safety and Health foundation, fabric materials such as towels, sheets, and handkerchiefs are only effective against virus particles larger than 0.41 u (microns).
In addition, cotton materials only protect against particles that are 1 u (microns) or larger in size.
This same study shows that materials containing a combination of nylon, polypropylene, and polyurethane protect against particles that are between 0.3-0.5 um (micrometers).
This same study shows that materials containing a combination of nylon, polypropylene, and polyurethane protect against particles that are between 0.3-0.5 um (micrometers).
Recap:
The N95 masks are most effective in protecting individuals from the transmission of particles greater than or equal to 0.1 u in size. Cotton fabrics are less effective and handkerchiefs are least effective!
The N95 masks are most effective in protecting individuals from the transmission of particles greater than or equal to 0.1 u in size. Cotton fabrics are less effective and handkerchiefs are least effective!
Conclusion:
Based on the information collected on filtration effectiveness, particle penetration & size, & respiratory exhalation, I believe it is fair to say that further scientific analysis is required to determine long-term efficacy of cotton, medical grade, and N95 masks.
Based on the information collected on filtration effectiveness, particle penetration & size, & respiratory exhalation, I believe it is fair to say that further scientific analysis is required to determine long-term efficacy of cotton, medical grade, and N95 masks.
While masks protect individuals from some respiratory droplets, they do not protect against coronavirus particles alone.
Considering how often many of us touch our masks, are they providing us with the protection we need?
Considering how often many of us touch our masks, are they providing us with the protection we need?
What do you believe is the purpose of mandating masks nationwide?
Feel free to openly discuss your thoughts. Please do so respectfully! Thank you!
RT AND SHARE! Thank you!
Feel free to openly discuss your thoughts. Please do so respectfully! Thank you!
RT AND SHARE! Thank you!
