All covered in the article. Touching face, chest, groin, etc is forbidden. And the shock is local to the touched area (unlike tasers).
https://www.independent.co.uk/news/world/americas/lapd-laure...
Sure, just like beating a suspect is.
It’s really hard to believe that an officer who’s wrestling someone hand-to-hand, possibly on the ground or against a wall, is going to restrain themselves from grabbing face or chest in the heat of the moment.