Ugh.

Any diving accident reminds of me some guys that got their commercial diving training at a school i went to long ago.  They were working in one of the cooling water inlet pipes of the Crystal River nook-u-lar plant and the pumps got turned on.

Or when two different guys I knew, both amateurs, were diving in a lake in Florida and discovered a cave and decided to go in without being prepared for cave diving.  They didn't have a map and didn't have a rope to let them trace their path back to the opening.  i think their deaths were probably worse.