Well, considering that the nozzle and the bail weigh somewhere around 5 or 7 lbs (forget the actual weight of it), combined with the pressure of the water in the hose, that thing can take a person's head off (or at least give them a serious concussion). Matter of fact, if I remember right, the film showed where it actually left marks in the steel where it hit.
During at sea firefighting, they hung a hose from a scaffold and charged it so that we could see how violently it whipped around. Then, the instructors told us to imagine something like that in a passageway or enclosed space. Scary stuff!
