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by Matt Jevon
Header image courtesy of Marissa Eckert
“To err is human” Alexander Pope
In his “Essay on Criticism,” Alexander Pope wrote “To err is human, to forgive divine.” However, if you are not prepared to err safely in cave or rebreather diving, you will come face to face with your preferred divine being, begging for forgiveness.
Stratis Kas’s book, Close Calls, a compilation of stories from a roll call of “who’s who” in diving, attests to the fact that the very best of us can and do make mistakes, or err. That they are still here to share these lessons with us affirms the huge amount of training, preparation, and experience required—and, as many will admit, no small amount of luck.
Gareth Lock, author of Under Pressure, is fond of the phrase “fail safely,” and with good cause. As he puts it, and I paraphrase; the human in the machine is at the heart of likely outcomes. In my own experience as a psychologist with expertise in human performance, the best systems, processes, and technologies are often outwitted by an unwitting fool or an arrogant wise man.
Today there is a surge of divers wishing to become cave divers, perhaps because it is perceived by some as the pinnacle of diving—in skill and status—or perhaps because it is seen as more accessible. Certainly, social media has given access to the incredible and beautiful environments that were once the playground of a select few. Divers are discovering that cave and modern diving practices, equipment, and training are making it a much safer environment until they start exploring virgin caves. Closed circuit rebreathers (CCR) are now mainstream and in wide use by many divers. In cave and deep dives, I would say they have become the primary tool; the limitations of open circuit scuba are seen as making it inappropriate for most “big” dives.
By the time a diver reaches their CCR cave course, they will, or should be, a knowledgeable, skillful, and competent diver on a CCR. Perhaps the odd one will find a shortcut, but it is the exception rather than the rule. In addition, the majority will already have some open circuit cave training, at least to intro level if not to full cave. The pathway from zero to hero in the cave is much longer and more difficult to shortcut than, say, open water to instructor status. Starting cave diving on CCR from cavern to full cave is, and should be, a much longer route.
[Ed.note: There are arguments against allowing a student to pursue any form of diving before gaining open circuit experience. Some argue that one should first become competent on open circuit in the relevant environment and THEN train in that environment on RB/CCR. This argument asserts that RB failures will find a diver on open circuit, requiring them to be proficient on this equipment in the relevant environment. These factors may be progressively more relevant with more complex environments.]
So, the CCR cave instructor is not dealing with an inexperienced CCR diver; nor, if they are as careful in their acceptance of students as most are, will they be dealing with an adrenaline seeking-junkie. See “Why We Cave Dive” (video) for reasons why some divers seek out the karst realm, as well as examples of divers we hope to encourage into the sport and those we prefer to avoid it.
The job of a cave CCR instructor is not to prevent all errors or mistakes. It would be both arrogant and foolish to believe that instructors can overcome human nature and the situational factors found in closed circuit cave diving. The instructor’s role is to lessen the frequency and severity and to mitigate the consequences of those errors as, and when, they occur. The instructor must do this in the course, ideally exposing students to likely errors or challenges in controlled conditions and embedding appropriate solutions. Students should acquire appropriate and controlled emotional, cognitive, and behavioural responses.
Being a cave instructor has a few significant differences from being a deep technical rebreather instructor. Here are a few:
Cave diving demands a greater equipment load. The number of backups can be summarised as “Three is two, and one is none.” So, three sources of light sufficient to complete an exit, three cutting devices, reel/spools, markers, breathing sources, and more. Before entering any overhead environment, the instructor must help students configure, become familiar with, and master accessing and manipulating their configuration. For this reason, cave divers opt for simple, easy solutions that are robust and definitely not prone to failure. This applies to their primary gear (CCR choice) and to every single piece of backup gear.
My own choices are primarily sidemount-based in the cave; the Liberty rebreather; Divesoft computers, primary reel and markers; plus O’Three 90ninety shell suit; and Apeks regulators and spools, all based on a Razor Sidemount System. In backmount I use a JJ-CCR, but I am now using the Liberty Sidemount rebreather as a bailout system. All simple, proven, tough, and each piece having substantial built-in redundancy/failure management options.
The instructor’s primary role—despite what many believe to the contrary—is, in any diving, to ensure that the students are safe and that they go home unharmed medically, physically, or mentally. Secondary to this is teaching skills, having fun, and awesome and epic dives. What a big ask in cave diving!
Progression in open water diving is more straightforward, especially using mixed gas. In the absence of narcosis, divers can build up deco time gradually and have a pre-rehearsed familiar exit/ascent permanently above them. Although not different in terms of time to exit, an open water deco ceiling somehow seems, to most, to be less of a psychological threat than several hundred tons of rock.
I have seen cave divers suddenly go from a point of being perfectly happy to being very unsettled and distressed within a few meters. There is actually a term for this: penetration stress. Penetration should be slowly built up over time with confidence in the linear distance built through many dives—some, but not all, including stressful exits (blind, bailed out, manual control, or touch contact).
To do this, an instructor needs considerable empathy. Some instructors may shy away from this and instead use a pseudo militaristic approach by battering, bullying, or belittling the student, constantly tearing off masks, shutting down gas, or more. (We are talking personality types here, not problem solving training.) Stay away from these people at all costs.
Instructors cope with a high task load. Not only do they have to monitor the group’s penetration distance, navigation, and teamwork, but they also need to monitor the students and their own PO2, decompression obligations and time to surface (TTL), bailout supply and limits, on board gas supply, scrubber durations, as well as to teach. In order to do this, a few tricks are employed. Some of these may be useful when diving in any CCR team:
- PO2 monitoring. HUDS can easily be seen reflected in students’ masks. It’s much easier than trying to read someone’s handset.
- Instructor Ghost Mode. Not just used for sneaky (pre-warned and planned) drills, the lights off/blackout ghost mode is often accompanied by pull and glide along ceilings or cave walls where no damage to the environment is possible. Instructors, especially on quiet CCRs, can get within a few centimeters of a student without their knowing, or they can shoot ahead. It is a bad practice to turn off (as opposed to cover) one’s primarily in a cave. The on-off button/switch is a weak point, especially at depth—sufficient working backups are required.
- Buddy lights on CCRs are brilliant for instructor/team monitoring, Divesoft’s show up well and Sentinels almost too well. When I was a student, my instructor found ghost mode difficult to fully pull off, since I saw this green light above me every time he tried it!
As an instructor, you want the students to develop their own robust team dynamic. If you are part of this, too often, students will always defer to your authority and default to you for leadership and solutions. So, if you do join the team to make up numbers, always be number 2, the weakest member, and play the part. Students don’t need to see how clever or skilled you are, they need to develop their own skills.
Navigation: Know the cave you are teaching in. For students’ first dives where I may not know them or their capabilities, I like to be in caves where a lost line would not be an issue for me in terms of exiting. Take Ressell in France for instance: A quick glance at the ceiling and a look at the scallop shapes in the rock, and I know which way is out.
These assume a whole other level of importance in cave and rebreather diving. A checklist is useful but only if you properly check everything on it. Turn backup lights on and off, breathe bailout regs at least 4-5 breaths. Fill and dump wings and drysuits. Prevention will ensure survival. It will also give students confidence, which means you are less likely to have issues, you’ll get a better response if you do, and you can actually enjoy the dive. [Ed.—Check out GUE’s Pre-Dive Sequence here]
Here are a few tricks I also like to instill:
- Link routines. For example, PO2 check and back reference. I use a hand mirror, so looking back is easy, and a quick over the shoulder is not difficult. Every time I check PO2, I look behind me. Caves often look very different on the way out and if I can, I will mentally imprint landmarks that I will see on exit. Some caves have distance markers every 100-150 m/328-492 ft on the main line, especially training caves. I’m not a huge fan of these for my own diving, as it’s a bit like graffiti; but, for trainees, PO2 plus back reference anytime you pass any navigational marker is a good routine.
- Wetnotes use. A good habit in a new cave is to make a note of time, distance, gas, and the navigation marking/direction in your wetnotes at any substantive navigation. On some dives, this will be two or three notes. Do this in some Mexican caves and you will get about 300 m/0.2 miles from the entrance and need a new Wetnotes book, so be sensible!
Finally, students will learn a lot of new skills, from what to do when you lose teammates, lose or become entangled in the line, encounter a broken line, have light and equipment failures, and more. Many of these will be done with blindfolds or blacked-out masks (mine say, “Use the force” on the front). On an open circuit, these situations can be challenging. On CCR, doing blackout drills while controlling loop content and volume, handling multi bailouts, and more, requires time both to learn and to embed. Don’t do it until you get it right, do it until you can’t get it wrong. Sometimes the lost line drill will provide unique challenges to get it right. If conducted correctly, you will probably get it wrong half the time!
Ultimately, graduating a new CCR cave diver is a moment to enjoy for the instructor—one with a need for appropriate gravitas and consideration. I have certified divers who were less proficient than other divers that I failed or asked to repeat. That was because a student’s attitude, mental strength, and sound decision-making ensured that they would likely go home safely from each dive. As the sign posted at the entrance of almost every cave reads, “Nothing in this cave is worth dying for.” There is an awful lot of cave diving worth living for, and I have been privileged to see some spectacular caves.
Barnson S.C. (2014) The Authentic Coaching Model: A Grounded Theory of Coaching. Human kinetics, Champaign, Il.
Troy A. Moles, Alex D. Auerbach & Trent A. Petrie (2017) Grit Happens: Moderating Effects on Motivational Feedback and Sport Performance, Journal of Applied Sport Psychology, 29:4, 418-433, DOI: 10.1080/10413200.2017.1306729
Swann, C., Crust, L., Jackman, P., Vella, S. A., Allen, M. S. & Keegan, R. (2017). Performing under pressure: Exploring the psychological state underlying clutch performance in sport. Journal of Sports Sciences, 35 (23),2272-2280.
The Darkness Beckons by Martyn Farr
Basic Cave Diving a Blueprint for Survival by Sheck Exley (Freedownload)
Psychological Skills for Diving @PSTforDIVING
Matt Jevon, M.Sc. F.IoD, is a Full Expedition level Trimix and Cave instructor on OC and CCR with TDI and ANDI. He is a JJ-CCR and Divesoft Liberty Sidemount instructor and dealer for Ireland. Matt’s personal diving has included cave exploration in the Philippines and wreck projects in Croatia and Ireland, and he was one of the inaugural Dirty Dozen in Truk! Matt has held accreditations as an interdisciplinary sports scientist, sports psychologist with the British Association of Sport and Exercise Sciences (BASES), and was a British Olympic Registered Strength and Conditioning Coach and invitee on the Olympic Psychology Advisory Group. Matt works in the high performance business as a board advisor and non-exec, high performance sport, and expeditionary level diving as a partner in South West Technical Diving in Ireland (), and hosts the Facebook page “Psychological Skills for Diving.”
Diving Into The Famous Ressel Cave
Belgium service member, cave explorer and tech instructor Kurt Storms takes us for a dive into the Ressel cave system located in Lot. Get out your reels.
By Kurt Storms. Photos courtesy of K. Storms unless noted.
The Lot and The Dordogne areas of France have an abundance of beautiful caves suitable for all levels of diving expertise, situated in glorious rural locations. Sites are mostly found on three rivers: The Dordogne, The Lot, and Célé. The Lot area lies in the northern extremity of the Midi-Pyrenees region, which stretches from the confines of the Dordogne Valley to the highest peaks of the Pyrenees, forming the heart of South-West France. Cave divers from all over the world return to dive here year after year. With over 20,000 known caves, France is one of the premier cave diving areas in the world. One of the most interesting regions lies in the Southwest, around the rivers of Lot and Dordogne. Here you find a multitude of long and deep caves with mostly crystal clear and relatively warm water, offering superb diving conditions. The water temperature averages 14º C/57º F and the visibility normally varies between 5-30 m/15-100 ft.
Finally!!! We can go to the Lot again. The COVID conditions have thrown a spanner in the works. But because we are all now vaccinated, we can finally leave. This time, for a week of training and then a week of diving holiday with my wife Caroline Massie. Two students (Jo Croimans and Bram Van Gorp) are with me for the training. The next few days, they will be busy with skills and dry teaching. Theory has already been given in Belgium so that we can get the most out of our dives.
Why the Lot?
The area in France is popular because most European divers take cave classes there so they don’t have to travel to Mexico or Florida. One of the most famous caves around here is Ressel. Ressel is located in the village of Marcilhac-sur-Célé, in the heart of the Lot. Most pictures you can see online show huge, dramatic blocks of white rock, flat structures, and the shafts of this cave. The facilities are pleasant, we have a large parking area for our cars, and finally there is also a conveniently located building with a toilet. From the car park we have only to walk about 100 m/330 ft to get to the entry point on the River Celé where we can put all our equipment needed for our dive.
The Ressel was first dived in 1968, by two divers of the speleo club Auvergnat. Martin and Debras reached 150 m/492 ft. It was only in 1973 that the line was extended to 300 m/984 ft, with a maximum depth of 30 m/100 ft. In 1975, Fantoli and Touloumdoian reached Pit 4 and went to a depth of 45 m/147 ft. Further exploration continued over the years, especially by Jochem Hasemayer in the early 1980s, where at 1100 m/3609 ft into the system he planted his knife in the rock to which he attached his line. This knife is still there.
On August 12, 1990, Olivier Isler was the first to cross Sump 1. The total dive time back and forth was 10 h 35 min. End of Siphon 1 is at Lac Isler, and from there on you can continue to the next siphons. Ressel consists of 5 sumps, of which siphon 1 is the longest (1850 m/6070 ft) and the deepest (83 m/272 ft). From Pit 4 onwards, the deep section begins, which can only be done with trimix mixtures. In the following years, the further sumps were explored by gentlemen like Rick Stanton, Martin Farr, and Jason Mallison. In 1999, the end of Sump 5 was reached. The total length on the main line is 4415 m/14,485 ft.
Spectacular Views In The First Section
To be honest, the visibility is spectacular all around. More than 10 m/33 ft visibility, which was near zero before the start in the Celé River—quite a change. As soon as we got to the entrance, the water cleared like snow in the sun. The first thought that ever crossed my mind was: How on earth did they find this cave? How, with the visibility of the river, did anyone see a hole that is 6 m/20 ft below the surface on one side—which is frankly not that big. Enquiries with the locals revealed that when the cave is full of water, you can even see a geyser in the river! Another impressive detail.
There is a rope that runs from the point where you get all the way into the cave, and it continues to the main line; you don’t need a primary reel here—it’s really easy to find the entrance, at 6 m/20 ft deep. Then there is a huge tunnel with white giant boulders, which is impressive.
The first dives were only up to the T (180 m/591 ft penetration), where the obligatory skills were practiced, so that later one can widen the comfort zone. This is also a very beautiful part, especially because of the large blocks that lie here. There are even two exceptional phenomena visible; these are two blocks consisting of white limestone, with a large black spot in it. You won’t find these black spots anywhere else. It is wonderful to be able to admire nature like this.
My wife, the students, and I got in, and on the first dive, with a sidemount set consisting of 2×80 cf (dual 11 ltr) tanks, we did the first T, taking the left corridor. On the next T, we continued toward the shaft to a maximum depth of 30 m/98 ft to take a look. It is so impressive! We felt like we were going to the abyss, and actually we were, to the abyss below ground and underwater. But now they were even more curious about the famous Pit 4 of the Ressel.
To be able to do this dive, we had to bring the right amount of gases. The first dive was with Jo Croimans, my student; he had his sidemount configuration with an extra 7 ltr along, I dived with my Divesoft Liberty SM rebreather. There we went, all prepared. The way there is about a 28 minute dive. On the way, I showed Jo the shunt that goes to the deeper part of the first loop. Enjoying the ride, we continued until we reached the point of the shaft.
Here I asked Jo if everything was Okay, he indicated that it was, and we descended to a depth of about 40 m/131 ft. I could see in Jo’s eyes that he was enjoying himself. But we didn’t have much time to enjoy ourselves, because we had to go back again. If you have deco, you can do it all on the way back on a nitrox 50 (NX50). For the advanced divers, you can take your oxygen at 6 m/20 ft and finish any decompression on O2.
It’s actually a great dive, and the cave allows for a variety of dives, just by choosing different depths in the tunnels, to have different perspectives.
Once we got to the top, Jo couldn’t stop exclaiming about the amazing beauty of this cave, and especially Pit 4. This made Caroline want to go and have a look too. This dive was done a few days later, when both gentlemen had gone home. This time we did the dive by scooter, a big difference. In 13 minutes we were at the shaft, and again I saw a happy face. How nice it is as an instructor to be able to pass on your passion. This is what we do it for. Ressel is one of the most beautiful caves in Europe. It remains an easy, accessible system.
The Ressel is and will always remain a special cave. Last year, I did the deep loop (1160 m/3806 ft long, 73 m/240 ft depth) here with two friends. And I still enjoy it when I talk about it. We still have to come back to do the rest of S1.
X-Ray: Pushing the Ressel—A Cave Diving Expedition in Lot, France by Erik Wouters (2013)
YouTube: Cave diving in France: Emergence du Ressel (2016)
Kurt Storms is a member of the Belgium military, and is an underwater cave explorer and active technical/cave/rebreather diving instructor for IANTD. He started his diving career in Egypt when he was on vacation, and the passion never ended. Kurt is also founder and CEO of Descent Technical Diving. He’s diving on several CCRs such as AP, SF2, Divesoft Liberty SM.
Kurt is also one of the pushdivers that is documenting a new slate mine in Belgium (Laplet). This project was news on Belgium Nationale TV. Most of his dives are mine and cave dives. In his own personal diving, Kurt’s true passions are deep extended-range cave dives. His wife (Caroline) is also a passionate cave diver. In his free time he explores Belgium’s slatemines. When he is not exploring, he takes his camera with him, to document the dives.
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