Certainly I am not the only person that has gotten a hair in their food while eating at a restaurant, but over the years, I have also found several other physical hazards of interest including bone fragments, wood chips, pieces of metal scrub pads and a screw.
These are all considered physical hazards. The pieces of metal scrub pad were found in a bowl of pasta. I surmise that the source was the kettle in which the pasta was cooked and the scrub pad piece had remained in the kettle after it had been cleaned.
The screw was found inside a glass of ice water. Further investigation by wait staff revealed that the screw had fallen from the inside deflector plate within the ice-making machine and cross contaminated the potable ice supply.