I’m a scientist, I train yearly to use N95 respirators. I want to share what I know about them. When I get certified every year they spray test particles around me and hook up a special mask that measures how many particles get through, just in case anyone is interested in what that involves. I use them because I operate a cell sorter that has the potential to aerosolize infectious particles from the human samples I use. We have an aerosol management system hooked up to the cell sorter, so in normal operation I don’t have to wear a respirator. If the aerosol management system clogs though, I am supposed to wear an N95 to clear the clogged machinery. The whole point is to protect me from infectious particles while I do that. The samples I sort are low risk, but we treat all human samples as potentially infectious, which is standard BL2 protocol. It’s been extremely disconcerting to see the US government try to claim that N95 masks don’t protect from infection. It’s true that you might not get a good seal if you aren’t trained in it, but it will help reduce exposure even if it’s not as good of a reduction as it could be with a full seal. Just watching a video of how to wear one would work for better public training. I do understand that SARS-CoV-2 is smaller than the pore size of the N95 mask, so that’s another reduction in effectiveness. It’s my opinion, and it’s only an opinion, that it would still reduce exposure. Healthcare workers are going to be exposed to high viral loads, so more will get through. The bottom line is that N95 masks have been used for years to reduce exposure for infectious particles. It’s disinformation to tell people otherwise.