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

Advertisement

Some thoughts about cave training…

First off, I need to declare a bit of a conflict here: Since I am a tech instructor and more importantly work for a training agency (and we do have cave diving courses on the menu), my take on certain aspects of “diver education” are bound to be biased. But all that taken into account, the primary message goes something like: If you want to dive caves, get trained. Simples, right?

In my opinion, cave diving is the oldest and purest form of technical diving. A whole lifetime ago, when I lived in England, I was a dry caver and heard about a small group of nut-bar pioneers who were making pushes through sumps in the Mendip Hills on scuba. At about the same time in the USA, a similarly labeled group of local lads where exploring the network of caves that honeycomb Florida’s North-western quadrant from Tallahassee in the north, south to Hernando County. These folks wrote the rules for extreme diving and 30 years later many of the techniques and kit modifications that they learned by trial and error, have become the gold standard for tech divers around the world.

One of the early gifts from cave diving to the rest of the tech diving community is accident analysis and specifically a shortlist of things to help keep divers safe.

  1. Seek proper (appropriate) training
  2. Maintain a continuous guideline to the surface (safety)
  3. Work within proper gas management guidelines
  4. Observe depth limitations
  5. Use appropriate, well-maintained kit

Over the years, those five points, whose authorship is attributed to the late explorer Sheck Exley, have been refined and developed to take changing attitudes and different environments into account.

Regardless, these guidelines remain a pretty good first step in the process of risk management, and they form the basic structure for building a modern technical diving course.

In case anyone is interested and for the record, the current interpretation of Risk Management is the identification, classification, avoidance and mitigation of risk with regards: Attitude, Knowledge, Training, Gas Supply, Gas Mix, Exposure (the combination of Decompression and Depth), Equipment, and Operations. These are expanded a little from that original list but certainly owe a lot to it.

Anyway, in North America, the oldest technical agencies are the two originally formed to teach cave diving to local divers. The NSS-CDS (National Speleological Society Cave Diving Section) and the NACD (National Association for Cave Diving) have been offering structured overhead courses to punters for over a generation. They are both based in North Florida. They both have instructors operating in Mexico (another hot-spot for cave diving), and the Caribbean, and so by default essentially focus operations on North America. The global situation involves some other agencies such as IANTD, NAUI, TDI, CMAS et al. And today, cave training is available through lots of channels.

Bottom line, there is no excuse NOT to take training if you are interested in diving caves.

There seems to be a sort of consensus among the major agencies and the process of earning a full cave diving certification takes about eight days and is broken into three or four steps: Cavern, Intro, Apprentice, Full. There are “post grad” programs that teach more advanced techniques like scootering and diving with stage bottles, sidemount diving and so on but the vast majority of certifications fall into those first four categories.

Actual standards and outlines vary a bit from agency to agency but the outline from NSS-CDS runs like this:

Cavern Diver As originally conceived, the Cavern Diver course was a recreational diving course, taught to recreational divers using basic recreational diving equipment. It was assumed most participants had little interest in penetrating caves beyond sight of the entrance. Today the need for that sort of a program has diminished. With readily available cavern diving sites in north Florida, such as Ginnie Spring and Blue Grotto, and the system of guided cenote tours in Mexico, recreational divers don’t necessarily need to take a complete, two-day course in order to enjoy a safe cavern experience. What is more common now is to use the Cavern Diver program as the first step in the complete eight-day Cave Diver curriculum.

It is where we introduce students to basic cave diving skills, such as equipment configuration, guideline and reel use, and specialized buoyancy control, body position and propulsion techniques. It is also a way to screen students to make sure they possess the necessary abilities before allowing them in the fragile cave environment.

Basic / Intro Cave Diver This is where students begin making actual cave dives — under some fairly strict limitations. By limiting penetration gas to roughly 40 cubic feet, avoiding decompression and prohibiting any sort of jumps, gaps or complex navigation, we allow students to focus on things like basic dive planning, communication and emergency skills. Students who want to gain limited cave diving experience on their own, at the completion of this program, may do so — provided they understand that the cave community will be keeping them on a fairly short leash.

Apprentice Cave Diver By the time students complete the Apprentice level, we will have covered most or all of the academic knowledge and emergency skills required for full Cave Diver certification. Students may receive a limited introduction to decompression diving procedures, as they pertain to cave diving, and will make some simple explorations off the main line. It is at this point that students are ready to gain some more realistic cave diving experience on their own, if desired. Nevertheless, they are expected to keep all dives well within the limitations of their overall experience.

(Full) Cave Diver The final step in the process, the focus here is on gaining additional practice of all fundamental and emergency skills, under more challenging conditions. Students are expected to demonstrate their readiness to be full-fledged members of the cave diving community.

Although a total of 16 training dives is required to reach this point, it is not unusual for students to have made many more practice dives on their own before full Cave Diver certification.” One of the first questions most divers have about cave training is what will I get out of it?”

ANY technical training is designed to challenge participants and to show them exactly where the borders of their comfort zone are. This is very true of a cavern or cave course. Other side-effects would be greatly improved basic skills; for example, progress in a diver’s mastery of buoyancy and trim, situational awareness and emotional control are big indicators for an instructor that someone is “getting it.”

AND of course, a cavern/cave class will take you to places that “normal” folks just don’t get to.

The next pieces of the puzzle of course are to decide where to take training and with whom.

Where is easy: Train where you are going to do the majority of your diving. Cave diving in the Yucatan is a whole order of magnitude different to cave diving in Ontario or Wisconsin. France is different to Brazil. North Florida is not the same as Australia. They all have their moments.

If asked, the default location that gets my thumbs-up is always North Florida. There are a couple of reasons. First would be the variety of caves. There are little tiny ones that you have to crawl through pushing tanks ahead of you; and there are huge passages that could swallow a hockey arena (whoops, Canadian reference. Sorry).

The second reason to train in North Florida is the quality of instruction. There used to be about three cave instructors I’d recommend but that list has grown to about 30. Some are Brits who fly in just to teach a class; one is Italian; one German; most are Yanks and Canadian; and a couple are even real Floridians.

One thing that is a constant challenge is weeding out the wanna-be instructors from the real thing. Rather than publishing a list of names and forgetting someone, here are eight questions you can ask.

1. How long have you been cave diving and how many cave dives do you make for yourself outside of the training programs you teach?

2. Do you teach full-time or part-time?

3. What other programs do you teach besides cavern and cave?

4. What kit configuration do you use and teach your students to use and why?

5. Can you give me a typical course schedule including dive sites and dive profiles

6. What specific changes do you look for in students before you sign off on their certs?

7. How many students did you fail last month, and how many did you pass?

8. What should be my primary take away from your course?

Cave diving is what I do for fun and relaxation with a handful of special mates, when I want to get away from the dive industry. Ironic maybe but cave diving feels more comfortable and secure than any other type of diving… which is probably why I have managed to resist the temptation to teach it!

When someone asks which cave I like the best, there’s really no answer. I like them all. There are certainly some that I will go out of my way to dive.

When I got word that the Eagles Nest — a deep and massive cave system off in the woods near Florida’s Gulf Coast — was being shut down for an indefinite period about 12 or 13 years ago, I literally left a birthday party early (mine) drove to the airport in Toronto and flew down to Gainesville and a mate waiting for me with a set of twins pumped full of trimix and three decompression cylinders. Next evening, I flew home. The Nest reopened years ago and I occasionally go back, but of the deep caves in that area, strange to say, it is not my favorite. Diepolder II gets that vote.

The entrance to # II is a small pond in the middle of a Boy Scouts of America Sand Hill camp ground just off Highway 50. At the bottom of the pond and its pale blue water is a fissure in the limestone that is wide enough for a diver in back-mounted twins to drop down (head-first) starting at about 15 metres to around 55. At the bottom, the cave opens up into a gallery which on the downstream side is about 40 metres from floor to ceiling with depths of 100 metres or more. Really a very cool dive.

Jackson Blue is another real favorite.

Its entrance is directly below a diving board at the business end of Merritt’s Mill Pond in Jackson Blue Springs Park, which is a few kilometers from Marianna up near the Florida / Alabama border. Yep, really the entrance is directly under the concrete platform that houses the dive board.

This cave is not deep — the deepest part of the main passage is about 30 metres — but it is long — about 3 kilometers at last count — and has plenty of little nooks and crannies to explore. JB is probably best known as a scooter cave. Lots of visitors fly through the first five to six hundred metres with the throttle wide open.

That first section of the cave features a passage that is wide, smooth and straight; perfect for flying in formation and a great spot to practice handling a scooter. The next section — probably from the Hall of the Mountain King on to the Banana Room or Stratosphere — seems to have the major pulling power to bring divers to this cave; however, last November a buddy and I spent a total of about seven hours on CCR playing around in the first couple hundred metres of the cave and had an absolute blast. I guess the object lesson is not to overlook the familiar when rating caves. On that score, JB is a real winner.

Florida’s caves are not decorated with Speleothems — no pretty flow-stones or drapery, no soda-straws, stalactites or stalagmites. To see these, one needs to venture a little south east to the Caribbean or west to Mexico’s Yucatan Peninsula or a long way south to Brazil.

The easiest decorated caves to get to, at least from my home a little north of Toronto, are in the Bahamas, and if pressed, this might be the one spot I would choose to go to for excellent cave diving year round above all others.

If you are making a list, Abaco Blue Hole, Dan’s Cave and Owls Hole are places I would like to get back to, tomorrow if possible. Send money to…

OK, so those are a few of my favorites, how about yours?