The Commercial Diver Network
The story is that an engineer moved a main valve and in doing so neglected to reinstate the "dead-mans" type valve handle and changed it to a normal 1/4" turn. One of the three in the bell had knocked this valve open and because it can not happen by mistake normally they had no idea. Also you will notice the 2 divers stay clear and allow the bell man to find the problem, nice thinking. The mist you can see forming is the water vapour coming out of the atmosphere as the pressure disappears. Scary stuff and captured so well by the divers clear "for fuc# sake"