/https://www.semanticscholar.org/paper/Filtration-Performance...
>Consistent with single-fiber filtration theory, N95 and P100 respirators challenged with silver monodisperse particles showed a decrease in percentage penetration with a decrease in particle diameter down to 4 nm.
I'm thinking that for each virus there is a chance that it will infect a cell. The higher the viral load, the higher the number of chances that you will get infected.
a lower number of droplets -> lower viral load -> less chance to be infected.
but somehow (some of the) particles going out will get stuck.
how is that simple?
(to explain more: there is a mechanism by which they help. so for them to not help (in total) , there must be a way in which they make things worse)
My doctor should wear something that has a filter capable of catching the virus, such as FFP3 respirator. When you breathe in, droplets get through the mask (this gets progressively worse as the mask gets wet) - and if the mask is not a FFP3, you're making a bet that none of the droplets that get through are contaminated, because the mask does not protect you from the virus, it merely protects you from some of the droplets around you; only the correct filter will protect you. The virus is around 50-100 nanometers.