Without wearing a mask, droplets travel to about 70 cm.
Wearing a mask, the bulk of droplets will travel about half the distance.
However, in both cases, there are still isolated droplets transmitted beyond 70 cm.
Mask efficiency is dynamic (not constant). It is reduced during cough cycles. The fluid dynamics and the interactions between the droplets, the filter, and the face influence mask efficiency. We show that after ten cough cycles, efficiency can drop ∼8%. The above is a conservative prediction considering that we model a mild cough incident and ten cough cycles. We should expect more significant efficiency reduction for severe coughing events, as well as when wearing a mask for a longer period.
The dosage and time of exposure to a virus affecting a human are not known and will vary across subjects. We examined 10% and 32% of droplets, which are smaller than their corresponding initial size, and found that they reduce in number during cough cycles when wearing a mask.
The diameter of the transmitted droplets is larger across cough cycles when no mask is worn.
The accumulation of droplets in the surrounding environment increases as the cough continues and is more significant without a mask.
With a mask, droplet penetration approximately reaches a mean value. Without a mask, the rate of the droplet penetration increases with cough cycles and tends to decrease after several periods.
The mask to face fitting is important. Even in the case of a tight fitting scenario, if there exist some small openings, this can lead to additional leakage of droplets around the mask, which cannot be ignored. It contributes to an additional reduction in the mask efficiency with respect to efficiency reduction induced by the cyclic behavior of the coughing incident.
By wearing a mask, it will also provide greater protection to the wearer as it blocks the droplets expelled from another subject and further decelerates the incoming jet.
The complex droplet interactions and fluid physics lead to interesting phenomena such as hot spots downstream of the mask and flow recirculation associated with buoyancy.
Which kind of masks block which viruses in which kind of weather (breeze or not) in which kind of setting (sitting idly close to each other vs. walking by a stranger briefly on the street)? I never seem to get these answered. I understand a mask if you're going sit right across from someone for over 15 minutes (strangely enough, they don't make you wear a mask when you are doing exactly this in a restaurant). I don't understand wearing one outside, when there is a breeze, and you're quickly passing by strangers on the sidewalk. The latter case makes no sense, and as far as I know, there is no scientific evidence that justifies wearing a mask in such a scenario.
More importantly, viruses weaken and eventually burn out. We're in the very late stages of this and deaths have flattened out to the basement floor. The only thing that needs to be pushed out to the public is that it is not so deadly to the point that an entire society needs to be masked up everywhere they go and businesses do not need to be closed.
Common sense precautions are all that's needed. At risk people should take their own precautions no differently than they would with a flu outbreak. Don't touch your face, nose and eyes and keep your immune system healthy. THAT'S IT!
There is no scientific evidence that masks work in nonmedical settings.
https://aip.scitation.org/doi/10.1063/5.0015044
Without wearing a mask, droplets travel to about 70 cm.
Wearing a mask, the bulk of droplets will travel about half the distance.
However, in both cases, there are still isolated droplets transmitted beyond 70 cm.
Mask efficiency is dynamic (not constant). It is reduced during cough cycles. The fluid dynamics and the interactions between the droplets, the filter, and the face influence mask efficiency. We show that after ten cough cycles, efficiency can drop ∼8%. The above is a conservative prediction considering that we model a mild cough incident and ten cough cycles. We should expect more significant efficiency reduction for severe coughing events, as well as when wearing a mask for a longer period.
The dosage and time of exposure to a virus affecting a human are not known and will vary across subjects. We examined 10% and 32% of droplets, which are smaller than their corresponding initial size, and found that they reduce in number during cough cycles when wearing a mask.
The diameter of the transmitted droplets is larger across cough cycles when no mask is worn.
The accumulation of droplets in the surrounding environment increases as the cough continues and is more significant without a mask.
With a mask, droplet penetration approximately reaches a mean value. Without a mask, the rate of the droplet penetration increases with cough cycles and tends to decrease after several periods.
The mask to face fitting is important. Even in the case of a tight fitting scenario, if there exist some small openings, this can lead to additional leakage of droplets around the mask, which cannot be ignored. It contributes to an additional reduction in the mask efficiency with respect to efficiency reduction induced by the cyclic behavior of the coughing incident.
By wearing a mask, it will also provide greater protection to the wearer as it blocks the droplets expelled from another subject and further decelerates the incoming jet.
The complex droplet interactions and fluid physics lead to interesting phenomena such as hot spots downstream of the mask and flow recirculation associated with buoyancy.
Will your mask stop my hot man butter from hitting your eyes?
Which kind of masks block which viruses in which kind of weather (breeze or not) in which kind of setting (sitting idly close to each other vs. walking by a stranger briefly on the street)? I never seem to get these answered. I understand a mask if you're going sit right across from someone for over 15 minutes (strangely enough, they don't make you wear a mask when you are doing exactly this in a restaurant). I don't understand wearing one outside, when there is a breeze, and you're quickly passing by strangers on the sidewalk. The latter case makes no sense, and as far as I know, there is no scientific evidence that justifies wearing a mask in such a scenario.
More importantly, viruses weaken and eventually burn out. We're in the very late stages of this and deaths have flattened out to the basement floor. The only thing that needs to be pushed out to the public is that it is not so deadly to the point that an entire society needs to be masked up everywhere they go and businesses do not need to be closed.
Common sense precautions are all that's needed. At risk people should take their own precautions no differently than they would with a flu outbreak. Don't touch your face, nose and eyes and keep your immune system healthy. THAT'S IT!
So out of the blue, masks existed for all these years and wow we just happen to find out masks work best in an election year. LOL.
people in asia have been using masks to stop the spread of viruses for decades now
Placebos have been effective for thousands of years, shill.
so instead of wind dissipating droplets you have ultra condensed virus plantation on your face? literally dripping with covid