Louis kicked with all his strength, but he wasn’t making much progress. The boat anchor he was trying to free so his group could move on to the next dive site was heavy in his hands, and he just couldn’t seem to ascend. He was breathing hard, really hard, but he just couldn’t get enough air from his regulator. He added air to his jacket-style BC, just trying to get to the surface with the anchor. The jacket was nearly full and it pressed on his chest making it harder for him to breathe. He let go of the anchor with one hand to pull down on his BC, but the weight caused it to slip, and go crashing back to the bottom. Just as quickly, he was rocketing for the surface totally out of control.
Louis was an experienced diver who had worked for many years as a divemaster on a local dive boat. Always a little overweight, he had nonetheless been active and it had never been a problem. In the last year or so, a number of personal and physical problems had gotten in the way of his diving and his overall activity and exercise. His body weight shot up dramatically while his fitness level had decreased. His doctor recently prescribed high blood pressure and cholesterol medications and advised him to lose weight, explaining that he was obese according to the body-mass-index scale. Louis was reluctant to begin a traditional exercise program, so he hadn’t done much to get in shape, but he knew he wanted to get back into diving. It was a stroke of luck that Louis was in the dive shop having his gear serviced when the manager told him they needed some help on the boat that coming weekend. Louis jumped at the chance to go diving again and feel like part of the team. He thought the activity would help get him back in shape quickly.
It was a typical day on the boat with passengers going out for two wreck dives. It was up to the two divemasters to set the anchor at each new site and free it afterward. When they got to the site, the other divemaster had placed the anchor on the wreck, wrapping the heavy chain around the steel of the wreck to hold the anchor in place. After all the divers were back on board, Louis jumped in the water to make a quick dive, often referred to as a bounce, to free the anchor from the wreck and swim up with it. Once the captain realized the anchor was free, he would begin pulling it up, but that always took a minute, so Louis had to swim part way up with the anchor. He couldn’t let it go free or the anchor might get caught on something in the process.
During his time away from the dive boat, the dive operation changed the anchor. It was heavier and a bit more awkward to control. The anchor was connected to a rope by a heavy chain. Since the other divemaster had taken the anchor down, the first time Louis had touched the anchor was when he was trying to get it free and bring it to the surface. But from his past experience, he felt confident he could handle the anchor. As Louis donned his gear, he struggled to get his wetsuit on. He made a joke that it must have “shrunk” during his layoff. He was red-faced and breathing hard by the time he got his gear in place and entered the water. The wetsuit and the BCD were both noticeably tight around his chest and midsection. Louis descended down the anchor line quickly and found the anchor. After a few minutes of struggle, he was able to get the heavy weight free. His progress was slow swimming up, though, as he wasn’t in good enough shape to carry the extra weight. He added air to his BCD jacket to provide some additional lift. He found himself able to move, but at the same time the pressure on his chest made it harder and harder to draw a breath. Louis was overbreathing his regulator, but the rapid shallow breaths were preventing him from actually moving fresh air into his lungs. He began to feel light-headed and dizzy. He was only about 15 feet off the bottom when he let go of the weight with one hand to adjust his equipment and ease the pressure on his chest. The heavy anchor slipped loose from his hand and the chain quickly ran through his fingers. The rapid change in his buoyancy immediately shot him toward the surface. Louis surfaced about 25 yards away from the boat. He immediately began waving his arms over his head, and the crew heard a weak call of “Help!” before Louis went unconscious. Resuscitation efforts were unsuccessful.
Every diver has heard the line to “breathe continuously and never, ever hold your breath.” We all also learn that if we don’t follow that rule, we can hurt ourselves very badly and very quickly. There is no way of knowing if Louis exhaled on the way up or not, but it really didn’t matter because his ascent to the surface was so fast — according to his dive computer, in just a few seconds he went from a depth of a little more than 60 feet to the surface. The air in his lungs expanded to nearly triple the volume in that same amount of time, much too rapidly for him to exhale. An autopsy later showed that he had significant amounts of air underneath his skin and in his arterial supply. The expanding air tore a hole in his lungs and leaked out into his body, entering his arterial blood supply. The bubbles went directly to his brain. This is called arterial gas embolism (AGE). The cause of death in this case was the AGE, but the triggers that caused this accident began long before that. Louis was out of shape and not physically fit enough to do the dives he was attempting to make. He should have taken the time to prepare his body regardless of his past experience. He also hadn’t been in the water or used his dive gear in a year. A quick trip to a pool or a local lake/quarry to practice some of his emergency skills and get comfortable again would have helped him tremendously. Additionally, it would have become apparent to him that his gear didn’t fit properly before he tried to use it on the dive boat. It probably would not have made a difference, but Louis’ size also made it difficult for the others to pull him on board and begin providing care. That delayed first-aid treatment as they struggled to get him on board. As he struggled to ascend to the surface, Louis used his BC as a floatation device for the anchor. When he dropped the anchor, he was suddenly extremely buoyant and there was no way he could have vented air fast enough to counteract more than 40 pounds of additional lift he was facing. It is very unsafe to use your personal BC as a means to float a heavy weight. He should have used a small lift bag to bring the anchor to the surface or the dive operation should have given him a communication system to allow him to free the anchor and then let it go while the boat brought it to the surface with the winch, rather than him attempting to swim it up.
Lessons For Life
- Take a diving refresher after a long layoff from the water.
- Make sure you are fit enough to make the dives you plan to make. A general level of fitness is essential to safe diving.
- Use gear that fits well and is appropriate for the dive.
- Use a lift bag to bring heavy objects from the bottom, not your BCD.
Eric Douglas co-authored the book Scuba Diving Safety and has written a series of dive adventure novels and short stories as well. Check out his website at www.booksbyeric.com