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I think you are considering a small subset of cigarette smoke, above 0.2 microns to push a point. But the point itself is irrelevant. Nobody caress if masks filter cigarette smoke or not.

Likewise nobody cares if non-N95 masks filter virus particles or not. They don't. Only properly fitted N-95 masks filter virus particles. Masks are used to to stop droplets.

he argument that they contain the droplets from a sneezing person might have some validity if the covering or mask does not have an exhilation valve which actually increases the velocity of the expelled droplets.

That's not my argument either although I inadvertantly adopted it. 99.9% of the usefulness of a mask in the real world is to stop droplets from the vocal cords. People who cough or sneeze into a mask should not be in public at all. The vocal cord droplets are about 1 micron and up: https://www.nature.com/articles/s41598-019-38808-z/figures/2

Granted a cloth mask will do very little to stop 1 micron droplets. A surgical mask should stop quite a few of them. Yes, you are correct about N-95 output valves making things worse. Those should not be used in public, only in hospitals or situations with COVID patients.

I do not think that we actually disagree on anything that has any substantial impact on anything. As far as the ratio of particles in cigarette smoke over .2 microns... I had never seen a study previously that made any analysis of the percentage of particles that were more than a certain diameter, but one would expect that the smoke from other types of fires would tend to have larger particles than cigarettes.

My nonscientific 25 years of experience crawling around in various types of fires would indicate that smoke gets into absolutely everything. Despite wearing protective clothing that one might think would stop it, everything stinks after you have been in a house fire including your underwear and your skin. That would indicate that the particles are smaller than one might believe and that dust masks and even N95 type masks are worthless in smoke, that is one of the reasons why we wear Self Contained Breathing Apparatus and not some type of filter mask.