To anyone at least little read up on the matter, the news that universal masking lessens the number of infected students and staff in schools comes as no surprise, as fewer viruses in the air means less risk for infections. Now there is even more proof.
Category: FFP3
It sort of says itself: if you put a filter in the stream of air entering your mouth and nose, you get fewer “things” entering your respiratory system. And respirators are very good at catching viruses.