bremnet says... Total N2 build up in the bloodstream is time dependent. If they're flitting about, zooming to the bottom and back to the top with very low Bottom Time, then the risk is (relatively) lower. But (IMO) not worth screwing with, as the downside (getting bent) is no picnic. Whether in a hole in Dubai or out on the reef, plan the dive and dive the plan. SFOGuy said: How come they don't get the bends soaring around between deep and shallow?