A thought experiment concerning “team bailout” when diving CCR in a cave…

LongO'THREE

First off: Can anyone explain the rationale behind “Team Bailout?”

Hang on… that needs to be rephrased.

Let’s start with this: Is it just me or is the concept of “Team Bailout” for CCR Cave Diving just bat-shit crazy?

Yea, that’s way closer to what I was thinking…

Ok, for those of you who may not be familiar with the team bailout concept, it suggests that a buddy team diving CCRs in a cave environment – you know, wet rocks, hard limestone overhead, perhaps an hour or more from the surface – that they carry sufficient bailout gas “…to get one team member back to fresh air from the point of furthest penetration.”

In certain circumstances, this approach may sufficiently protect team members from harm, but those circumstances should not include the category of diving the vast majority of us engage in.  I believe, a better, more satisfactory practice is for EACH diver to carry MORE gas than is required to get themselves back to fresh air from the point of furthest penetration.

The arguments I’ve heard against using this more conservative tactic is: 1) carrying multiple bailout cylinders is a pain; 2) the likelihood of more than one CCR failure among a team is too slight to consider; 3) calculations for the volume of gas required in a high-stress situation adhere to a well-defined formula corrected for all variables, and therefore it is possible to calculate with a degree of accuracy sufficient to be safe.

Experience is a better guide to best practice behavior than deductive logic, and I have limited experience in this area. So, perhaps my paranoia is unjustified; but here’s a scenario we might all give some thought to before our next cave dive.

Here goes:
Three CCR divers were in the back of a low-flow cave. Each carried an aluminum 40 filled to capacity, which lumped together was enough gas to get any one of them out of the cave and back to dry land. Even at double their normal consumption rate, this was the case. Their dive was well within the parameters of team bailout therefore.

At the worst possible time, Diver A’s CCR went belly up. He could not revive it in any way, and has to bailout. The team began its swim out. A little sooner than expected, but still more than one-third of the way out, Diver A’s bailout cylinder was empty, and he asked Diver B for her cylinder. She suddenly realized that by giving it up, she will have no contingency gas herself. The surface was still a good swim away. Very reluctantly, she handed over her bottle. Momentarily distracted by her thoughts, she floated to the cave’s ceiling and took a minute to recover, which held the team’s progress to the surface still further. Stress levels in all three team members was now peaking. None of them was comfortable.

They were in fact, more small failure, one additional glitch away from a total melt-down. A surprisingly short while later, Diver A – who had been thinking for the past several minutes, what would happen if he got a bottle with a dodgy regulator or had a free-flow, and whose respiration rate had understandably elevated – once again was down to seeds and stems. This time in his second bailout. He turned to Diver C. Diver C had been thinking about this hand-off for a while. He was VERY uncomfortable donating his gas… however, he did so. Several minutes later, the team arrived in the cavern area. Diver A had barely sufficient gas to conduct a safety stop, but did so. Just as the team left the overhead, his regulator began to breath very, very hard.

On shore, while shucking their gear, the group was uncharacteristically silent, each with their own thoughts. What do you think the outcome of this incident was:

  1. This group did not cave dive together ever again
  2. This group rethought their bailout strategy
  3. This group  continued to dive team bailout

Save

Self-Assessment: an antidote to complacency?

Cleaning out old files and finding a copy of my original dive-plan template – something my buddies and I used for several years when we first started to do deep mix dives – I remember why we scrapped it and drew up a new one: It’s missing an important element.

If memory serves, the error was pointed out by Bret Gilliam. At that time – around 1996/97 – Bret was president of Technical Diving International (TDI) and he was gathering information for student manuals and asking members to contribute things like teaching notes, learning goals, and so on. Among the various bits and pieces I contributed was a spreadsheet template of the dive plan my buddies and I were using, and that I was also teaching students to use.

“It’s good but you’re missing something…” he told me after looking it over for a few minutes. “Something critical.”

I checked it a couple more times and to my eyes the plan looked pretty comprehensive and exhaustive. I told him I could not see what was wrong with it.

“There’s nothing in it about conducting any level of self-assessment before you jump into the water,” he said. “Don’t you think that’s worthy of a line or two?”

There is a well-established maxim that tells anyone who’s listening that complacency kills experienced divers. Checklists and Dive Plans are intended as a good first-line of defence against that sort of complacency. They are intended to counter human nature and swing attention back to things that it’s easy for divers, even very experienced ones, to take for granted and overlook. For instance, I’ve seen divers forget or simply not bother to conduct a positive/negative check after refilling a diluent bottle on their rebreather. A checklist can serve to remind someone with this level of complacency not to be a Muppet.  But, as Gilliam pointed out to me, the most complete, comprehensive and meticulous dive plan cannot prevent things going horribly wrong if the folks executing it aren’t as present-and-correct and as ready as their equipment to do the dive.

Self-assessment is now included in the pre-dive checks for all TDI and PSAI courses, but like the requirement to analyze and mark EVERY bottle of gas, or pre-breathe EVERY regulator – or any of the other listed items on a checklist or dive plan – it is entirely self-policed, and quickly becomes worthless if any one member of a dive team shortcuts that “policing operation.”

The process is simple enough. You ask yourself a couple of easy-to-answer questions and you answer them honestly. Better yet, when the dive leader has completed her self-assessment, she should check with everyone on the team to make sure they all “passed” the self-assessment check.

When we dive – even on those dives that seem like a simple bimble around in shallow water – we must ask ourselves if our plans account for any and all hazards. For the purposes of providing a realistic answer, a hazard in the case of diving is any agent or situation posing a credible level of threat to our life, health and property, those of any team member, or the environment in which we intend to dive.

When we make a self-assessment, that assessed risk includes things that are not visible or readily apparent to our buddies. One is our personal level of comfort.

To check this is the case and that our planned dive is within our comfort-zone, ask: Considering ALL the risks associated with the dive as planned, do I find them acceptable? Does the plan cope with things, events, which have some significant probability of occurrence during that dive? Rottweilers hit the fan and precisely when and how depends on circumstances that may not be predicable. Does the plan make allowance for this and am I comfortable if it does not?

Recreational divers, even those engaged in kick-ass technical dives, are under no contract and are not protected by legislation. Each of us is responsible for our safety and well-being, and – to some extent through enlightened self-interest and the tenets of friendship – with that of our buddies. Honest answers to these questions will help keep us safe and should be asked before every dive; no matter how simple and inconsequential the dive seems.

In addition, there are several other questions we might ask ourselves as part of the “self-assessment” process that should be carried out long before we pull on a drysuit. They concern personal health. We need to ask if we are comfortable with: our personal heart health; are we free from angina, epilepsy, diabetes, asthma, dehydration, and fatigue? Is our cardio and physical fitness up to the stress of the dive as planned? Do we have adequate strength to do the dive as planned? Have we learned and practiced the critical safety skills required on this dive as planned? Are we diving drunk, with a hangover or stoned? Are we physically and mentally ready to do the dive as planned and if something hits a fan while we are down there, are we ready to deal with it appropriately?

It may seem a little odd, but self-assessment should also ask: Do we believe in our buddy’s abilities and do we feel they have the skills and experience required to do the dive as planned? Are we being over-confident expecting ourselves and each member of the team to do the dive as planned? Does that hold up if we become separated? Do I feel the same should it become necessary to rescue a buddy on this dive… can I rescue them and can they rescue me?

Self-assessment does not always return a positive answer. But self-assessment is a positive habit to fall into and it needs to become part of the pre-dive preparations for EVERY dive… especially any dive that requires the use of decompression gases to manage a decompression obligation, or that takes place in a hard overhead environment.