Yeah, we aren't allowed to bring anything magnetic near our NMR machine.
If so much as a paperclip gets sucked into it, it could take the machine out of service for weeks. The magnet would need to be quenched, the helium vented off, and a technician flown in to recharge the magnet and get it started again.
Last I checked, there's a global helium shortage, so even if we cold get enough helium to get it restarted, the overall bill would be in the high 5 figures.