I volunteer for a lifesaving organization in Germany and the bowline is one of the most important knots there. One example is diving, where the diver is secured by a bowline around his hip.
Interesting... Around here if divers are working off a line, they're tagged in with a short lead to the mainline. The lead will have carabiners on either end that are either factory stitched in place, or clipped into a figure-eight. Those aren't meant to be under any tension though, they're just for maintaining orientation.
If a diver is attached to an actual haul line (not common, but happens in swift-water recuse scenarios), then they're going to be clipped in via a carabiner, which is tied on with a double-loop figure-eight. The double-loop figure-eight is the standard "if your life is gonna depend on it" knot around here.
(I am not a rescue diver, but do support dive operations from time to time)
