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March 2006 Vol. 32, No. 3   RSS Feed for Undercurrent Issues
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Tech Diving, Rebreathers and Wrecks

when it might not be for you

from the March, 2006 issue of Undercurrent   Subscribe Now

Many divers who earn “open water” certifications choose not to pursue further formal training, opting for practical experience though their diving. This often works well since practical experience is just as relevant in producing a qualified diver. At least, in warm water and not too difficult conditions.

As divers age, their limitations increase: possible reduced stamina, higher blood pressure, cardiac problems, reduced flexibility and mobility, arthritic joints, vision and hearing loss, deteriorated muscular strength, postoperative limitations, side effects of medications, and general reduced physical fitness. Of course, there are exceptions, but for nearly all, as a diver ages, limitations increase that can affect their fitness to dive.

Often I’ve been deceived ... On trips I had a 46-yearold
in such poor condition that even without her equipment
on she couldn’t climb up the ladder without assistance
. . .a morbidly obese 55-year-old who couldn’t
reach down to put on his own fins;

Even so, older sport divers with increasing disposable income often seek more challenging diving, ranging from the deep wrecks of Bikini to the wilds of the Galapagos. Most often, typical sport diving experience is insufficient. In fact, it often produces what I call the Into Thin Air mentality, referencing the fatalities that occurred during the May 1996 expeditions to the summit of Mt. Everest as chronicled in Jon Krakauer’s book of the same name.

There were amateur climbers on the mountain who shouldn’t have been there. Yet they had the money to pay the hefty expedition fees and figured the alpine guides would look after them despite their limitations. One wealthy New Yorker even paid extra to be “short-roped” to the summit, where she had a Sherpa essentially drag her up the face of Everest on a tether. When the weather turned unexpectedly severe, several amateur climbers died along with the professional guides accompanying them.

Diving Beyond One’s Capabilities

Of course, well intended, but under-qualified folks sign up for diving trips beyond their capabilities. Most operators screen applicants in advance. Typically, they require an applicant to detail their training, diving experience, medical history, fitness to dive, etc. However, some eager divers misrepresent their diving skills or medical fitness. The problem is compounded because operators have the economic need to get customers for these expensive trips. So sometimes unsuited divers make the journey. Some get injured. A few don’t return. The lucky ones have close calls or get scared out of their wits when they can’t cope with the harsh conditions.

I’ve had divers on rebreather or deep dive trips whose applications looked suitable and they came across convincingly in phone interviews. Yet, often I’ve been deceived. On trips I’ve had a 58-year-old who didn’t find it necessary to reveal that he had only one lung; a 46-year-old in such poor physical condition that even without her equipment on she couldn’t climb up the ladder without assistance; a 64-year-old with four cardiac events in the last two years; a morbidly obese 55-year-old who couldn’t reach down to put on his own fins; a 52-year-old taking three antidepressant medications who had recently attempted suicide; and a 57-year-old in such poor shape he couldn’t swim 20 ft.

While these cases were daunting, they were unknown to us until we had to engage in rescues. But the worst offender was a 26-year-old male in great shape who signed up to dive rebreathers at Cocos Island. We require a minimum of 150 logged dives, experience on live-aboards, current experience, Nitrox certification, and decompression ratings. He claimed to have all and promised to bring his Nitrox card with him. He showed up with a forged Nitrox card (determined later) and a “pencil whipped” log book showing 200-some dives in a variety of challenging conditions, and appeared to meet our criteria. Only when he had trouble assembling his scuba gear before an orientation dive and could not figure out how to read his computer did he finally confess that he had just completed his basic scuba training and had only done seven dives. He figured diving at Cocos was just another extreme sport merit badge that he could bluff his way through and the staff would babysit him through any problems. We shut him down completely and he spent ten days at Cocos getting a suntan but not getting wet.

It’s exciting to expand your diving universe. But the ocean is a fickle mistress and you won’t master her without specialized training. And you owe it to yourself and to the dive operator to be honest about your experience and limitations. You can bluff but that doesn’t help once you’re underwater. So, you hiked up Mt. Rainier on a sunny July day. That doesn’t qualify you to climb Mt. Everest.

Furthermore, incapable divers can also risk the lives of fellow divers who may forsake their safety to rescue them. I once had to break off my own decompression to surface and rescue a diver who had incurred a deco obligation and then surfaced anyway because he couldn’t understand his computer readout. Ironically, although I dragged him back down to complete his deco and an extra margin for his omitted stop, he emerged unscathed. I got bent. Luckily, the vessel had a great supply of oxygen and I could treat myself in the field.

And, if they don’t put a fellow diver at risk, they can certainly ruin a dive trip for everyone else. When a boat has to cut short an expensive trip to return an injured diver to port, a diver who shouldn’t have been there in the first place, it is not a happy outcome.

The Step to Technical Diving

Rebreather diving is the rage. By comparison, open circuit equipment is simple and relatively foolproof. If you don’t turn the valve on, the regulator won’t breathe. But you can actually breathe through the closed or semi-closed loop rebreather without turning on the gas supply. There is no warning that things are amiss until you pass out from hypoxia. Rebreathers have demanding and unforgiving maintenance regimens as well as lengthy check lists before diving. If you’re unwilling to handle the technical demands then stay with open circuit.

Not long ago, the Okeanos Aggressor, Sea Hunter and Undersea Hunter offered onboard rebreather rental and training programs during their 36-hour crossing to Cocos Island. However,the problems of first time users were frequent and severe. Now divers must not only bring their own rebreathers, but also provide proof of certification and credible records of logged dives.

If you want to dive deep wrecks, you need formal training for deep dives. First, you’ll quickly learn whether your physical condition is acceptable. Then, you’ll find out with an instructor at hand whether you can mentally and physically manage the dives. But not all advanced technical courses are equal. Some amount to little more than a few dives in benign settings with an instructor looking on. I’ve got a long track record with both the TDI and IANTD programs, whose instructors must evaluate divers realistically before they’re allowed to train them – some divers get excluded – and then monitor them closely throughout the training.

Deeper diving and rebreather diving typically require decompression and proper training. With open circuit scuba, the safest gas is Trimix, but in some remote areas like Bikini only air is available. This decreases bottom time, increases decompression time, and increases the risk of narcosis. Since narcosis affects each diver differently, in training you learn your narcosis tolerance so you can establish a proper dive plan.

Trimix diving requires specialized training, as does decompression diving. A record of doing “safety stops” will not give you the skills to hit multiple stops, switch gases, execute precise ascent rates and handle contingencies where escape to the surface is not an option. Expecting to go deep and stay long at Truk is not for untrained divers.

If you use double cylinders, you need the strength to tote them and the ability to swim with the increased drag and weight. Backup regulators, stage cylinders, surface marker lift bags, deco bottles, etc. can create a daunting amount of gear to manage, while requiring skill, flexibility and strength. Wreck penetration requires lines, reels, and possible staging of exit cylinders. The record of unqualified divers lost inside wrecks due to narcosis, silting, or simply getting disorientated from multiple turns down passages is too long to cite.

Areas such as Cocos or Malpelo islands require a diver to roll off an unanchored dive launch with no descent line and drop through a ripping current to 60-120 feet, then get established on the bottom or be swept into the blue. Dives proceed to a series of stationary observation points for marine life, with drifts between set points. Current diver skills and compass or natural orientation skills are essential to arrive underwater where the action is. Finally, the dive often ends with a long drift in the blue for a safety stop, perhaps even decompression. For the inexperienced, dives like this can be terrifying and stressful. Even a fit diver cannot maintain a headway against more than about a one-knot flow for long. Add in the vagaries of updrafts and downdrafts and we have the ingredients for disaster if you’re not comfortable with such conditions.

Truth Always Wins

Thirty-five years ago, I was part of a Navy deep diving team filming submarines passing by us at high speeds from about 20 feet away. The diving officer reminded us that the key to the generous retirement program was surviving that long. It was good advice then. And still is.

So, don’t be in denial about your own physical limitations, training and skills and be honest when you sign up. Sometimes the most valuable lesson to be learned is that you shouldn’t place yourself in an environment that exceeds your ability or comfort zone. You must have the independent skills to deal with contingencies entirely on your own. The only help you’ll get will come from your conditioning, training and skills – and the decisions you make. After all, the ocean is a fickle mistress.

Author Bret Gilliam has been professionally involved in diving since 1971 and has logged more than 17,000 dives. He was the founder of Technical Diving International (TDI). He also founded Fathoms Magazine and leads exotic dive expeditions worldwide. He lives on an island in Maine and travels on dive projects six months of the year

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