Sharp things and distractions are a painful combination. This afternoon while chopping an onion to go in a chicken in the woods stir fry, in the kitchen of my flat with a freshly sharpened knife a little voice behing me said...
"Is it OK if I sit here, I won't say anything to you"
A second later I was on my way to the first aid kit for a plaster.
So PLEASE PLEASE remember, DON'T distract someone when they've got anything sharp in their hands. and definately never tap them on the shoulder as they might turn around and then it gets painful.
Amazingly I've even heared of similar incedents where it was a shotgun and the results of that can be imagined.