I entered an MRI room once when my wife was getting ready to be scanned. I had a metal Cross pen in my shirt pocket. Although I was 10 feet back, the pen flew out of my pocket, across the room, and stuck to the magnet. It was scary.
Even after adding MRI levels of force a 1oz pen is still gonna be something that you can pick up.
Not removing it sounds dangerous though.
It would come off ok, this happens from time to time, but that facility needs to lift its game.
Peripheral staff (nurses, anaesthetic techs etc) visiting are the usual source of these accidents.