The study with 4 people has the right idea, just needs more people and definitely needs to figure out why they weren't detecting the virus on the inside of the mask (from people who were coughing and had the virus).
Most home made masks reduce the transmission rate of the virus coming in, by about 40-60%. Surgical masks are about 70-80% filtration coming in. You are still getting some exposure, just not as much. The transmission radius going out - as you put it, is a very good way of explaining it. It isn't stopping material from getting out during a cough, but it is trapping the larger droplets and impeding the flow somewhat of the tiniest ones.
The study's statement here: "Alternatively, the small aerosols of SARS–CoV-2 generated during a high-velocity cough might penetrate the masks." matches up with testing data 3M and other companies have done on cotton and surgical masks.
The study with 4 people has the right idea, just needs more people and definitely needs to figure out why they weren't detecting the virus on the inside of the mask (from people who were coughing and had the virus).
Most home made masks reduce the transmission rate of the virus coming in, by about 40-60%. Surgical masks are about 70-80% filtration coming in. You are still getting some exposure, just not as much. The transmission radius going out - as you put it, is a very good way of explaining it. It isn't stopping material from getting out during a cough, but it is trapping the larger droplets and impeding the flow somewhat of the tiniest ones.
The study's statement here: "Alternatively, the small aerosols of SARS–CoV-2 generated during a high-velocity cough might penetrate the masks." matches up with testing data 3M and other companies have done on cotton and surgical masks.