[zajio1am]

I do not really understand why hospital workers and others that use masks daily for whole shift still use single-use N95 masks and not half-face respirators with reusable filters, like 3M 7500 (https://www.youtube.com/watch?v=-5zbj3_ezqE). They are more comfortable and fit much better.

[goldcd]

My guess is that it's to prevent cross-contamination.

i.e. wearing a mask will protect a user, but the outside of it isn't sterile. So if you come off a covid ward, easier to just bin the mask and take a new one, than wash the outside of a re-usable one.

[iguy]

I don't know either, but lots of stuff in hospitals is disposable, because this is easier than figuring out a system to disinfect & re-use it.

Although perhaps that makes more sense in an operating theatre than many of the lower-risk places people now wear them, all day.