A long, long, long, time ago, during my college years... I was a volunteer working in an ER.
It was a fairly small ER, and I was allowed to do A LOT of things that volunteers today aren't. It was nice, because my help was genuinely appreciated, and I was made to feel like part of the staff.
Anyway, one day an elderly lady came in with trouble breathing. While the doctor examined Mrs. Gasping, the nurse and I hooked her up to some oxygen. She went to turn on the O2, handed me the oxygen mask, and asked me to put it on the patient.
So I was placing it on the lady's face when the elastic band snapped over, pulling the plastic mask to the side.
To my horror, her whole nose flew off. We hadn't been told she had a prosthetic nose to replace one lost to skin cancer.
The nose clattered over the gurney and onto the floor. I screamed, thinking I'd somehow accidentally torn her nose off. The nurse shrieked. The doctor jumped back. I saw my entire dream of a medical career vanish.
Her husband started laughing, picked up the nose, put it in her purse, and set the oxygen mask on correctly.
I hid in the bathroom for a while.