My dad went to a conference recently, and when I asked him about what happened there he said it was a conference for people in biosecurity. When I asked him about the different kinds of biosecurity stuff that the different groups did, he said one did air filters in schools. He was talking about how in schools when there are air filters they don't work most of the time because teachers often unplug them because they're going WOOOSHHH in the middle of the class when the teacher is trying to talk over a horde of screaming children. Which is very chaotic, and I understand that, but there are methods for school classrooms that are less noisy, like far-UVC lamps. A place that I do think air filters could be used currently is school cafeterias.
When you think of school cafaterias, you think about bad school lunches and noisy tables of kids talking. But must people don't think about how many germs are being spread through the air there. If a first grader sneezes, it could affect a fifth grader who had never talked to that first grader in their life. Putting an air filter, or multiple, in a school cafeteria would be very helpful. Also, students are talking, and it will already be noisy. Since students are sitting at tables talking to each other, and it's not one teacher trying to be heard by a bunch of students who are more than five feet away from them, it's going to be noisy regardless, and while an air filter would add to this noise it would reduce the number of kids who get sick by a lot.