There was an accident in a small Swedish hospital a few years ago, the patient scheduled for the MRI arrived with a 13 kg / 28 lbs weighted vest that he for some reason persuaded the MRI nurse to put on (I believe they were friends at the gym). The nurse did, but during the MRI session he left the monitoring room and went in to talk to the patient – and got pulled in by the magnetic field. Almost got strangled to death.
Alarm went off, security guards came running – and were also pulled in… In the end it took hours to get everybody out, the nurse and one or two of the security guards were injured, and the MRI machine was damaged.