Contrary to expectations of a sport that was years ago considered dangerous, there are few fatalities through scuba diving, but I was present in the Bahamas when a diver tragically lost his life during a dive. What happened? He went off on his own, ran out of air and at only around 18m deep he struck out for the surface. As designed, the Suunto computer he was wearing did not record the time he spent between 2m and the surface but it recorded everything else in its log and told the story. He probably made it to the surface but he dropped back down and drowned. He was a recently certified diver who had made a previous dive-specific trip so he was not totally inexperienced but why did he drop? When we recovered his body all his equipment was still in place. That is to say he was still wearing his weightbelt. Running out of air to breathe is obviously very serious. Every diver should manage their air supplies properly by keeping an eye on their pressure gauge. I admit that there may have been times when, distracted by an underwater photography subject, I have cut it very fine and arrived at the surface without enough pressure in my tank to inflate my BC. It’s not something I recommend but I’ve been able to orally inflate it instead. That’s what the oral inflation valve at the end of the corrugated hose is for. If this unfortunate person had reached the surface he could have done that but I am inclined to think that by this point he’d got into a panic and might have lost all sense of reason. He might have tried to use the BC’s direct-feed control but of course it would not have worked if his tank were empty.There is another option. Think about dropping your weightbelt in an emergency. Struggling to swim with full kit at the surface, if that diver had thought to drop his weightbelt he would still be alive today.You should not have to do this in order to swim up to the surface if you are correctly weighted to be neutrally buoyant, but you might need to do it once you are there. Dropping your weightbelt has the effect of making you buoyant so you don’t really want to do it at depth and enjoy an out-of-control ascent. You must also be careful not to drop it on divers that may be below you and for this reason practicing this act is discouraged at crowded inland dive sites. Before BCs, and their forerunner the ABLJ, were invented, dropping the weightbelt was enshrined in diver training. It was the only way to stay at the surface during an emergency. Correct use of a BC allows for neutral buoyancy at any depth and one only has to swim up a little for the gas within the BC to expand and start to become positively buoyant. You then need to jettison some air for reasons of controlling the speed of ascent. Dropping the weights effects a sudden increase in buoyancy that could get out of control. For this reason dropping weights tends to be glossed over in training. So how to drop a weightbelt? It used to be the last thing you put on in the old days. That was so that it was never fouled by other straps passing over it. Today, it’s often put on before the BC and tank.
It is not sufficient to simply flip the buckle and let it fall. You need to be sure it falls away cleaning from you without snagging. Think about dropping you weightbelt and its ramifications. Avoid being over-weighted so that you can be neutrally buoyant at any depth but know that you can always drop your weightbelt once you are near to the surface. Unhitch it and swing it away from you and once it is clear, before you drop it!