That was the first thing I thought of, Keg.
And that is the first risk that anyone, and his or her supervisor, doing a proper risk assessment of the task should have thought of, too.
That's why I keep using the word "proper" in front of PPE. In this case, a paper mask that slips off at the first wiggle of a nose and can't be repositioned because both the officer's hands are occupied arresting someone is not "proper" PPE.