How Not To Scuba Dive

There are several certification courses for scuba (e.g. PADI, SSI, NAUI). All of them cover the basic concepts of scuba diving as defined by the World Recreational Scuba Training Council (WRSTC). It might look easy to throw on a tank and jump in the water, but not following the basics can lead to death. Here's a video of a couple divers who skipped some basic points, namely not diving below 100-130ft on a recreational dive and to always pay attention to your oxygen supply levels. If the diver taking the video did not intervene, it is likely that they would have run out of air at 130ft deep.
Site - Divers Alert Network (DAN)

YouTube - Scuba Diving Intervention


WRSTC - Common Scuba Hand Signals