Community
Nourishing My Inner Tekkie At Bonaire Tek
What goes on when you bring together a group of 80-some enthusiastic tech divers, provide boats and beach access, rebreathers, doubles and scooters, ply them with plenty of helium, nitrox, oxygen and sorb, nightly brain food and then turn them loose—sans gloves—on some of the most bodacious reefs on the planet? Here InDepth editor-in-chief Michael Menduno tells all, well almost, of what went on.

by Michael Menduno
Header photo by Matthias Leno courtesy of Buddy Dive Resort
Where is Bonaire? That’s the question that diving friends were still texting me as I boarded my plane for the eighth annual Bonaire Tek gathering—a week-long tech diving love fest held 6-11 OCT on the small island of Bonaire in the Leeward Antilles, in the southeastern Caribbean. The island—technically a special municipality of the Netherlands—along with Aruba and Curacao, form the ABC islands located 80 km/50 mi off the coast of Venezuela, and is known for diving, windsurfing, and sailboarding.

I was on assignment for InDepth and looking forward to meeting German Arango a.k.a. “Mr.G,” who oversees the technical diving program at the Buddy Dive Resort, which hosts the event. Sporting long wavy hair and a salt-n-pepper beard, the 45-year old Colombian-born tech diving instructor who teaches primarily for GUE, as well as for NAUI and PADI, was responsible for conceiving the idea for Bonaire Tek and has organized the event for the last eight years. “My goal is to build a community here,” he told me when he picked me up at the airport.
And he is succeeding. Bonaire Tek, which is sponsored by Dive Rite, SubGravity, SANTI, KISS Rebreathers, and Silent Diving has grown each year since its inception. This year there were 81 divers—57 men and 24 women—from 11 countries, including North and South America, Europe and Australia representing 52 open-circuit (OC) and 29 closed circuit rebreather (CCR) divers.
The concept of a tech diving “camp” embodied by Bonaire Tek, the pioneering TekCamp held at Vobster Quay in the UK, Underworld Tulum’s Cave Camp, and the Ponza Rebreather Meeting in Ponza, Italy, has proven itself to be a fantastic vehicle to engage geeky divers in tech, and help spread the love. To wit, bring in a manageable-sized group of avid tech divers of varying experience levels, provide plenty of awesome diving, an opportunity to take courses, try-out new gear, share stories, enjoy depth-full talks on various aspects of diving, eat, drink, meet new friends, and hang with the tribe.

To be sure, Bonaire Tek, which ran from Sunday through Friday, didn’t disappoint! There was a communal breakfast every morning, followed by dedicated OC and CCR tech boats and a variety of shore diving. There were people who came simply to dive, and others who were taking courses. In the afternoons there were additional boats and dockside try-dives on AP Diving, KISS, O2ptima and xCCR rebreathers, various side mount rigs and SubGravity scooters. In the evening, we gathered for one or more talks, and dinner and drinks. Rinse and repeat.
Bodacious Bonaire

Pulling my nitrox 50 deco while gently gliding along the phantasmagoric wall of boulder-sized coral heads amidst hundreds of bright colored reef fish, following our mix dive to the wreck of the Windjammer more than 50 m/163 f below, gave new meaning to the notion of Caribbean reef diving! More surprising, we conducted the dive from shore. The water was consistently 30 C/86 F at the surface and dropped to 27 C/80 F at around 50 m. Visibility was in the 30-40 m/100-130 f range, and they tell me the reefs are almost always diveable. It’s easy to get spoiled by Bonaire!
In recreational diving circles, or maybe it’s the island’s tourism bureau, the island is known as the “Shore Diving Capital Of The World!” For good reason. On the leeward (diving) side of the island, which is approximately 39 km/24 mi long by 5-8 km/3-5 mi wide, the reef and drop-offs begin within a short swim from shore (windsurfing and sailboarding are prevalent on the windward side). The same is true of the even smaller island, Klein Bonaire, which is nestled in the leeward embrace of Bonaire, a mere 800 m/0.5 mi swim away. From the air, the two islands look like an amoeba swallowing a bite-sized morsel of food!
In fact, dive marketing mavens have identified more than 80 dive sites along Bonaire’s leeward side. As cardiologist and tech instructor, Doug Ebersole, one of the presenters, put it, “Where else can you make a 200-foot plus wreck dive, followed by a wall dive and see sailfish blennies?” Bonaire!
According to the amicable and animated Mr.G, the reefs are near pristine for several reasons. First, is the arid island’s low population density—there are only 20,000 permanent residents on the island, little rainfall, and no agriculture. Read: minimal impact population pressure and little chemical runoff.
Second, the Dutch have long instituted conservation measures; the island was designated a marine sanctuary in 1979. As Mr.G instructed the assembled divers during his initial briefing, “Whatever you do, don’t touch or take anything; gloves are not allowed!,” he said, giving a new twist to the old urban meme, “NO GLOVE, MORE LOVE!”
Buddy Dive also supports the Reef Renewal Foundation Bonaire, headed by local marine biologist and tech diver, Francesca Virdis, and they host part of their nursery on Buddy’s Reef, which begins 20m/64 f from the dock. The island is also known for its wild donkeys and flamingos.
Bodacious Buddy Dive
Much of the success of the event was due to the dive-oriented venue and the amazing support provided by Mr.G and his team. Located right on the water’s edge, and offering 24/7 diving, Buddy Dive Resort is arguably a bit of diver heaven. Eleven yellow stucco buildings with spacious, clean, air-conditioned apartments, patios to dry dive gear, two pools, a dockside dive service center, and 24/7 accessible wooden airy dive lockers and tanks—no surcharge for banked nitrox 32, along with a drive-thru fill station. There are also two restaurants, car rentals, laundry service, and drinkable de-salinized water. All you have to do is dive!

Providing daily diving support and gas for 81 enthusiastic tech divers is no small task, and Mr.G’s team of divemasters and gas blenders handled it with aplomb, albeit with little sleep—the fill team pulled multiple late to all-nighters. Divers were assigned individual numbered cylinders including their singles, doubles, stage bottles, and CCR tanks, which were filled to meet their daily gas needs in an area called the “Tech Block.” It likely represents the largest gas blending operation in the Caribbean. That’s where divers picked up their cylinders, analyzed, and labeled them for the day’s diving.
Buddy divemasters, many of whom had been GUE trained, provided diver support on the daily boats and typically accompanied dive teams. We were even joined by head of dive operations for Buddy Dive, Augusto Montbrun, who with his team, spent a morning supporting two teams of tech divers.
Bonaire Tek Stats

Tank Fills: 2100
Liters of helium consumed: 180,000
Liters of oxygen consumed: 324,000
Liters of banked nitrox 32: 1,000,000
Kilograms of sorb: 360 kg/792 lbs.
Number of dives conducted: 660+
Hours underwater (est.): 550+
Hours of decompression(est.): 225+
Deepest dive: 107m/350 ft
Big Smiles: 81,000
Celebrating Our Tech Sisters
The theme for this year’s Bonaire Tek was “Ladies First,” helped by SANTI, and fittingly the gathering had the largest female turnout yet, representing roughly 30% of participants. Yay!

Argentinian tekkie Marcia Gallego’s festive dive themed nails.
Accordingly, Mr.G arranged for several female-focused presentations beginning with a homage to “Female Tech” presented by Buddy Dive’s PADI Course Director and tech, cave and CCR diver, Lars Bosman. His presentation began by recognizing early diving pioneers, such as Simon Melchior Cousteau, Dottie Frazer, Zale Perry, and Dr. Sylvia Earle. He then went on to profile contemporary tekkies like explorers Jill Heinerth, Verna Van Schaik, and Immi Wallin, photographer Becky Schott, shark whisperer Cristina Zenato, stuntwoman and model Szilvia Gogh, Helene “Wethorse” Graauw, who invented the “She-P,” and Bonaire’s own Virdis.
Ebersole followed a few nights later with a presentation entitled “Women’s Issues in Technical Diving.” After offering a disclaimer that he was “NOT a woman,” he proceeded to discuss the science on decompression sickness (DCS) and gender, DCS and menstrual cycles, diving and pregnancy, breast augmentation, DCS and birth control pills, menopause and more. He later wrote up his talk, which we will publish in the December issue InDepth.
Mr.G had also arranged for morning yoga and core-building exercise sessions which were enthusiastically attended by humans of both genders. Interestingly, they also tried to arrange for a women-only boat dive day, but there were no takers, even after repeated attempts, to the apparent surprise of the organizers. One female observer noted women want to be included, not set apart.
Steeped In History

Bonaire Teksters, whose average age was likely pushing 50, were offered a trio of diving history presentations over the course of the week. On our first night, we were treated to a talk, “Maritime Archeology in Bonaire” by Dutch marine archeologist, Ruud Stelton PhD. He explained Bonaire’s early history, initially as a cattle plantation for the Spanish in the 1500s, and later, in the 1600s, a plantation of the Dutch West India Company supplying salt used for preserving food to Europe on the backs of slave labor. Salt continues to be Bonaire’s largest export today, and salt fields are visible in the north, as well as the huts where slave populations lived. Moorings, abandoned anchors, and artifacts can also be found.
Dive Rite founder and cave diving pioneer, Lamar Hires, regaled us with tales of some of the early developments in cave diving with his talk, “Cave Diving: Mission Specific.” He began by explaining the early 1980s development of sidemount with cave diving pioneer Woody Jasper, regarded as the “father of sidemount.” At the time, the test of a good cave diver was to the ability to swim to the Hinkel restriction (975m/3200 f) and back to Ginnie Springs on a set of doubles.
As Hires explained, part of their motivation for diving sidemount was finding cave that the “big boys” hadn’t yet explored. That would be famed explorer Sheck Exley and Woodville Karst Plains project (WKPP) co-founder Bill Main. “We knew if it required sidemount, Sheck and Bill hadn’t been there,” Hires said with Mona Lisa-like smile. He also discussed the skepticism that greeted the first isolator manifolds as a result of three cave diving fatalities. Of course, isolator manifolds eventually became the standard.

Hires went on to talk about their first use of oxygen as a decompression gas (instead of simply using it to pad their air tables) at Cow Springs in 1986. Hires and his team were able to incorporate oxygen because anesthetist John T. Crea and his company’s Submariner Research Ltd. computer program was able to cut air with O2 tables, requiring them to pull their oxygen stop at 9 m/30 ft. It was a fascinating talk.
I also gave a two-part talk, “Revisiting The Technical Diving Revolution: An Insider’s Look at the People, Projects and Technology that Created Technical Diving.” In it, I discussed the emergence of tech diving in the mid-to-late 1980s, the development of “special mix” diving, nitrox, the origins of the name ‘technical diving,’” early tech diving fatalities, the persistence of deep air, and the development of consumer rebreathers. Call it a “history stop!”
Joys of Team Diving
The diving is what brings people to these events. I was no exception.
I made my first shake out dive of the trip with Bosman, who took me to what he said was one of the best reefs on Bonaire, called Lac Cai, on the windward side of the island. After negotiating our rocky beach entry with doubles and a pair of SubGravity Ecos S DPVs, we conducted a luxurious 75-minute dive along the length of the breathtaking reef wall max depth 23 m/75 f surrounded by bands of sea turtles, rays, and large silver tarpon. It was a sublime beginning to a glorious week in the water.

I am currently getting re-certified for mix diving, and in the process of completing my GUE Tech 1 (normoxic helium diving) training. As a result, I was excited about spending the week diving with friends from Team GUE Seattle, who had a contingent of ten, including a non-GUE rebreather diver, as well as some recreational divers.
Though not everyone’s cup of tea (mind that Kool-Aid!), I have a growing appreciation for GUE’s standardized approach to diving—standard config, gases, deco, protocol. It puts everyone on the same page so they can focus on the main goal: Having Big Fun!
The T1 class is all about underwater problem solving while maintaining one’s buoyancy and trim in the water column, and most importantly one’s COMPOSURE. After all, just like nitrox, breathing helium is easy, you just breathe in, and then breathe out. The induced problems we dealt with in class included resolving bubbling first stages and manifolds, out of gas situations, non-working deco gas, and failed mask, which occurred one at a time or in combinations, for example, while shooting an SMB.
So imagine my glee upon descending on our first dive to see my dive buddy, photographer Matthias Lebo, with first stage seal bubbling. I knew what to do. I immediately swam over to affect a fix by trying to screw down his left post. To no avail. Full disclosure: I had forgotten my lesson; valves don’t move when pressurized. (I’m sure Gareth Lock, Mr. Human Diver, has a reference for me: fact retention). Argh! Not to worry. My teammate Bert Brezicha reached over, checked that Lebo was breathing from his right post, shut down his left, purged the reg, tightened the valve, and powered up the post. No bubbles, no troubles; we were good to go. I will never forget that again!!

Though I was skeptical at first, I have come around and really appreciate GUE’s team or operational approach to deco, which again makes things easy and keeps the dive team together. I suppose it’s ironic, that just like the early days of tech, GUE dives tables instead of computers, in this case generated by DecoPlanner software (based on Buhlmann Z-16 and or VPM-B algorithms). Dive computers are there as a back-up though not really needed.
They also use standard gases such as Trimix 21/35 (21% O2, 35% He) for depths from 30m-45m/100-148 f, trimix 18/45 from 45-60M/148-197 f etc., and deco gasses like nitrox 50 and oxygen, which makes things easy. In Bonaire, we were primarily diving nitrox 32 or trimix 18/45 for deep dives with nitrox 50 for decompression.
What’s more GUE modifies its deco procedures to make them easy to carry out as a team using only gauges. So instead of everyone chasing their own dive computer, we ascend as a team to our first stop at a 9m/minute rate (30 f/min), depending on the dive make our gas switches to say nitrox 50 at 21m/70f (team-based gas switch protocol) and proceed to work our way back to the surface.
Rather than stop for example for one min at 21 m, one at 18 m, two at 15 m, two at 12 m, three minutes at 9 m up and then say 20-minute at the 6 m stop as calculated from DecoPlanner, GUE-ers average their stop times so they stop two minutes at each stop from 21m to 9m and then pull their required 20-minute deco at 6 m. The resulting plan? “Twos and 20!” Easy to remember, and easy to conduct. In fact, that’s the deco we—the shallow team—did on our Windjammer dive to 50 m/164 f with 20 minutes bottom time. Deco on deeper and longer dives get a little more complex.
Modify the numbers from the deco algorithm? Is nothing sacred? The argument being that the algorithms i.e. one minute here, two minutes there etc. are just an approximation anyway; decompression is not (yet) a precise science. In fact, according to a recent DAN Europe study, 94% of hits occur within the specified table or computer. GUE’s thinking: better to prioritize team unity and operations. See Jablonski’s article “Decompression, Deep Stops, and the Pursuit of Precision in a Complex World, Part Three; Bubble-wise, Pound Foolish.”
A final lesson in protocol: We were running late. I was waiting for my gas; doubles with 18/45, and a nitrox 50 stage. Team Seattle was waiting for me. I finally got my tanks, analyzed my gas, got labels, filled them out hurriedly, and then inadvertently mixed up the labels. I put my 50% label on my doubles and the 18/45 on my stage. I didn’t notice. However, my GUE teammate, anesthesiologist Heléné Pellerin did. “Michael, your labels are incorrect. You must re-analyze your gas,” she said with no uncertainty in her French Quebec accent. “No problem. I’ll just write new labels, “ I answered, not yet realizing where this was going. “No,” she said, “you must re-analyze your gas.”

WHAT!#@? I just did. OK, I was a bit perturbed but reluctantly reanalyzed my gas; didn’t want to push the point with my new team. The gas hadn’t changed, and this time I correctly applied the new labels.
With later reflection, I realized my tech sister was absolutely right and I was glad that she spoke up, and that I complied. Do you know how many of our tribe have died breathing the wrong gas at depth? Answer: Way too frigging many!
I’m reminded of a recent post that the human Lock recently re-tweeted—a post from Lt. Gen. David Morrison, “The standard you walk past is the one that you accept!” It’s a matter of building safe habits and a fail-safe system to catch our humanness. I mean I knew what was in my bottles, but if someone else had used them, for whatever reason, they wouldn’t, would they? In fact, after that I made it a point to ask Heléné when I had a question of protocol or procedure. She was always helpful.
Ironically, we shared the tech boat with a NAUI Tec team from Argentina headed by NAUI greybeard, Daniel “Dani” Millikovsky, along with instructor Ken Head from Texas. I learned that they were also diving their own standard config, standard gasses, and runtime tables generated by RGBM algorithm. They wrote their runtime schedule down on the wrist slates. Completely different from GUE of course that mandates Halcyon WetNotes!
Just kidding! It was clear to me that our commonality greatly outweighed our differences, and we had a number of enlightening in-depth discussions—the subject of a future article.
Community Safety
SubGravity and TEKDive USA cofounder Randy Thornton appealed to our higher angels in his talk, “Make Tech Diving Great Again.” He began with a startling statistic that the average time that a new tech diver stays in the game is two years! The Reasons: they never get truly comfortable with gear, and/or being in the water, and yet they often push themselves to do too much too fast, resulting in too much stress—all of which is NOT fun. “At the end of the day, we are here to have FUN,” he reminded us!
Thornton, who is a very experienced tech and CCR instructor, offered sound advice: learn progressively, gain experience at each level before moving on, pick the mentors you want to emulate, keep an open mind, and show up at classes ready to learn. He admonished instructors to maintain their integrity and to say, “No” if their student was not ready for the next class.

GUE Seattle deep-diving team exiting the water after diving on the Windjammer.
Not one to preach what he doesn’t practice, Thornton, who during his pre-diving career put in his 10k hours as a professional musician, shared that he takes a new class every year and makes it a point to dive with other age groups and training agencies. “Mastery is just a momentary point in time,” he observed. “It’s the process that’s important.”
Finally, he thoughtfully reminded us about the use of social media and implored us to just say “NO” to cyberbullying. “We need to be sharing information and knowledge and celebrating each other’s successes, not running each other down,” he emphasized, offering mountain biking forums as an example of communities that are doing it right.
Here was my favorite anecdote in his talk:
There was a farmer who won the award for the best corn year in and year out. A reporter discovered he shared his seed corn each year with his neighbors. “How can you afford to share your best corn with your neighbors when they compete with you each year?” the reporter asked. ‘Why sir,” said the farmer,” Didn’t you know that wind picks up pollen from the ripening corn and swirls it from field to field. If my neighbors grow inferior corn, cross-pollination will steadily degrade the quality of my corn. If I am to grow good corn, I must help my neighbors to do the same.
In other words, you have to give it away to keep it! Thornton ended with a depthful plea, “Share with others through mentoring and giving back, and help build our community.” Amen.
Silent Diving’s founder and president, Mike Fowler, gave the final presentation titled, “How Do We Make Diving Safer?” He began by reviewing the grim statistics on rebreather diving deaths; 317 deaths from 1998-2018, 146 from 2010-2018 or about 16/year. Fifty-five percent were solo diving, 30% failed to monitor their sensors and or ignored warnings, 30% conducted poor assembly and pre-dive checks, the list goes on.
Fowler then discussed the role of “human or non-technical factors” in these incidents and offered the Rebreather Education and Safety Association (RESA)’s 10 Point Plan. One of his comments stuck with me, “If there’s any doubt, there is!”
Sadly, a very visible and loved member of our community who was an experienced rebreather diver, anesthesiologist and hyperbaric doctor Fiona Sharp died in Bonaire on a solo rebreather dive, a few days after the event ended, in what appears to be a result of human factors. See the accompanying article, “Fiona SharpYou Will Be Sorely Missed!,” in this issue.
To honor our dear sister’s passing, Mr. G has decided to dedicate next year’s Bonaire Tek 2020 to improving diving safety. It’s something we can’t get enough of. Hope to see you there next year.
Dive Deeper

Award-winning underwater cinematographer Matthias Lebo, who is based in Zurich, Switzerland, produced a series of videos of the event. The Croatian born filmmaker spent most of his twenties traveling the world – primarily Australia, South East Asia and Europe – working as a Scuba Diving Instructor, intensifying his love and appreciation for the ocean. Lebo operates a small film production company named “Liquid Images.” He’s made it his mission to show as many people as possible the beauty and wonders of the underwater world. He hopes to raise awareness of how fragile our marine ecosystem is. You can also find him on Facebook. Enjoy!
Bonaire Tek Final Recap Vid of the Week

Michael Menduno is InDepth’s executive editor and, an award-winning reporter and technologist who has written about diving and diving technology for 30 years. He coined the term “technical diving.” His magazine “aquaCORPS: The Journal for Technical Diving”(1990-1996), helped usher tech diving into mainstream sports diving. He also produced the first Tek, EUROTek, and ASIATek conferences, and organized Rebreather Forums 1.0 and 2.0. Michael received the OZTEKMedia Excellence Award in 2011, the EUROTek Lifetime Achievement Award in 2012, and the TEKDive USA Media Award in 2018.
Community
Twenty-five Years in the Pursuit of Excellence – The Evolution and Future of GUE
Founder and president Jarrod Jablonski describes his more than a quarter of a century long quest to promote excellence in technical diving.

by Jarrod Jablonski. Images courtesy of J. Jablonski and GUE unless noted.
The most difficult challenges we confront in our lives are the most formative and are instrumental in shaping the person we become. When I founded Global Underwater Explorers (GUE), the younger version of myself could not have foreseen all the challenges I would face, but equally true is that he would not have known the joy, the cherished relationships, the sense of purpose, the rich adventures, the humbling expressions of appreciation from those impacted, or the satisfaction of seeing the organization evolve and reshape our industry. Many kindred souls and extraordinary events have shaped these last 25 years, and an annotated chronology of GUE is included in this issue of InDEPTH. This timeline, however, will fail to capture the heart behind the creation of GUE, it will miss the passionate determination currently directing GUE, or the committed dedication ready to guide the next 25 years.

I don’t remember a time that I was not in, around, and under the water. Having learned to swim before I could walk, my mother helped infuse a deep connection to the aquatic world. I was scuba certified in South Florida with my father, and promptly took all our gear to North Florida where I became a dive instructor at the University of Florida. It was then that I began my infatuation with cave diving. I was in the perfect place for it, and my insatiable curiosity was multiplied while exploring new environments. I found myself with a strong desire to visit unique and hard-to-reach places, be they far inside a cave or deep within the ocean.
My enthusiasm for learning was pressed into service as an educator, and I became enamored with sharing these special environments. Along with this desire to share the beauty and uniqueness of underwater caves was a focused wish to assist people in acquiring the skills I could see they needed to support their personal diving goals. It could be said that these early experiences were the seeds that would germinate, grow, mature, and bloom into the organizing principles for GUE.



The Pre-GUE Years
Before jumping into the formational days of GUE, allow me to help you visualize the environment that was the incubator for the idea that became GUE’s reality. By the mid-1990s, I was deeply involved in a variety of exploration activities and had been striving to refine my own teaching capacity alongside this growing obsession for exploratory diving. While teaching my open water students, I was in the habit of practicing to refine my own trim and buoyancy, noticing that the students quickly progressed and were mostly able to copy my position in the water. Rather than jump immediately into the skills that were prescribed, I started to take more time to refine their comfort and general competency. This subtle shift made a world of difference in the training outcomes, creating impressive divers with only slightly more time and a shift in focus. In fact, the local dive boats would often stare in disbelief when told these divers were freshly certified, saying they looked better than most open water instructors!
By this point in my career, I could see the problems I was confronting were more systemic and less individualistic. In retrospect, it seemed obvious that key principles had been missing in both my recreational and technical education, not to mention the instructor training I received. The lack of basic skill refinement seemed to occur at all levels of training, from the beginner to the advanced diver. Core skills like buoyancy or in-water control were mainly left for divers to figure out on their own and almost nobody had a meaningful emphasis on efficient movement in the water. It was nearly unheard of to fail people in scuba diving, and even delaying certification for people with weak skills was very unusual. This remains all too common to this day, but I believe GUE has shifted the focus in important ways, encouraging people to think of certification more as a process and less as a right granted to them because they paid for training.

The weakness in skill refinement during dive training was further amplified by little-to-no training in how to handle problems when they developed while diving, as they always do. In those days, even technical/cave training had very little in the way of realistic training in problem resolution. The rare practice of failures was deeply disconnected from reality. For example, there was almost no realistic scenario training for things like a failed regulator or light. What little practice there was wasn’t integrated into the actual dive and seemed largely useless in preparing for real problems. I began testing some of my students with mock equipment failures, and I was shocked at how poorly even the best students performed. They were able to quickly develop the needed skills, but seeing how badly most handled their first attempts left me troubled about the response of most certified divers should they experience problems while diving, as they inevitably would.
Diving Fatalities
Meanwhile, I was surrounded by a continual progression of diving fatalities, and most appeared entirely preventable. The loss of dear friends and close associates had a deep impact on my view of dive training and especially on the procedures being emphasized at that time within the community. The industry, in those early days, was wholly focused on deep air and solo diving. However, alarmingly lacking were clear bottle marking or gas switching protocols. It seemed to me to be no coincidence that diver after diver lost their lives simply because they breathed the wrong bottle at depth. Many others died mysteriously during solo dives or while deep diving with air.
One of the more impactful fatalities was Bob McGuire, who was a drill sergeant, friend, and occasional dive buddy. He was normally very careful and focused. One day a small problem with one regulator caused him to switch regulators before getting in the water. He was using a system that used color-coded regulators to identify the gas breathed. When switching the broken regulator, he either did not remember or did not have an appropriately colored regulator. This small mistake cost him his life. I clearly remember turning that one around in my head quite a bit. Something that trivial should not result in the loss of a life.
Also disturbing was the double fatality of good friends, Chris and Chrissy Rouse, who lost their lives while diving a German U-boat in 70 m/230 ft of water off the coast of New Jersey. I remember, as if the conversation with Chris were yesterday, asking him not to use air and even offering to support the cost as a counter to his argument about the cost of helium. And the tragedies continued: The loss of one of my closest friends Sherwood Schille, the death of my friend Steve Berman who lived next to me and with whom I had dived hundreds of times, the shock of losing pioneering explorer Sheck Exley, the regular stream of tech divers, and the half dozen body recoveries I made over only a couple years, which not only saddened me greatly, but also made me angry. Clearly, a radically different approach was needed.
Learning to Explore
Meanwhile, my own exploration activities were expanding rapidly. Our teams were seeking every opportunity to grow their capability while reducing unnecessary risk. To that end, we ceased deep air diving and instituted a series of common protocols with standardized equipment configurations, both of which showed great promise in expanding safety, efficiency, and comfort. We got a lot of things wrong and experienced enough near misses to keep us sharp and in search of continual improvement.

But we looked carefully at every aspect of our diving, seeking ways to advance safety, efficiency, and all-around competency while focusing plenty of attention into the uncommon practice of large-scale, team diving, utilizing setup dives, safety divers, and inwater support. We developed diver propulsion vehicle (DPV) towing techniques, which is something that had not been done previously. We mostly ignored and then rewrote CNS oxygen toxicity calculations, developed novel strategies for calculating decompression time, and created and refined standard procedures for everything from bottle switching to equipment configurations. Many of these developments arose from simple necessity. There were no available decompression programs and no decompression tables available for the dives we were doing. Commonly used calculations designed to reduce the risk of oxygen toxicity were useless to our teams, because even our more casual dives were 10, 20, or even 30 times the allowable limit. The industry today takes most of this for granted, but in the early days of technical diving, we had very few tools, save a deep motivation to go where no one had gone before.

Many of these adventures included friends in the Woodville Karst Plain Project (WKPP), where I refined policies within the team and most directly with longtime dive buddy George Irvine. This “Doing it Right” (DIR) approach sought to create a more expansive system than Hogarthian diving, which itself had been born in the early years of the WKPP and was named after William Hogarth Main, a friend and frequent dive buddy of the time. By this point, I had been writing about and expanding upon Hogarthian diving for many years. More and more of the ideas we wanted to develop were not Bill Main’s priorities and lumping them into his namesake became impractical, especially given all the debate within the community over what was and was not Hogarthian.
A similar move from DIR occurred some years later when GUE stepped away from the circular debates that sought to explain DIR and embraced a GUE configuration with standard protocols, something entirely within our scope to define.
These accumulating events reached critical mass in 1998. I had experienced strong resistance to any form of standardization, even having been asked to join a special meeting of the board of directors (BOD) for a prominent cave diving agency. Their intention was to discourage me from using any form of standard configuration, claiming that students should be allowed to do whatever they “felt’ was best. It was disconcerting for me, as a young instructor, to be challenged by pioneers in the sport; nevertheless, I couldn’t agree with the edict that someone who was doing something for the first time should be tasked with determining how it should be done.
This sort of discussion was common, but the final straw occurred when I was approached by the head of a technical diving agency, an organization for which I had taught for many years. I was informed that he considered it a violation of standards not to teach air to a depth of at least 57 m/190 ft. This same individual told me that I had to stop using MOD bottle markings and fall in line with the other practices endorsed by his agency. Push had finally come to shove, and I set out to legitimize the training methods and dive protocols that had been incubating in my mind and refined with our teams over the previous decade. Years of trial and many errors while operating in dynamic and challenging environments were helping us to identify what practices were most successful in support of excellence, safety, and enjoyment.
Forming GUE
Forming GUE as a non-profit company was intended to neutralize the profit motivations that appeared to plague other agencies. We hoped to remove the incentive to train—and certify—the greatest number of divers as quickly as possible because it seemed at odds with ensuring comfortable and capable divers. The absence of a profit motive complemented the aspirational plans that longtime friend Todd Kincaid and I had dreamed of. We imagined a global organization that would facilitate the efforts of underwater explorers while supporting scientific research and conservation initiatives.
I hoped to create an agency that placed most of the revenue in the hands of fully engaged and enthusiastic instructors, allowing them the chance to earn a good living and become professionals who might stay within the industry over many years. Of course, that required forgoing the personal benefit of ownership and reduced the revenue available to the agency, braking its growth and complicating expansion plans. This not only slowed growth but provided huge challenges in developing a proper support network while creating the agency I envisioned. There were years of stressful days and nights because of the need to forgo compensation and the deep dependance upon generous volunteers who had to fit GUE into their busy lives. If it were not for these individuals and our loyal members, we would likely never have been successful. Volunteer support and GUE membership have been and remain critical to the growing success of our agency. If you are now or have ever been a volunteer or GUE member, your contribution is a significant part of our success, and we thank you.

The challenges of the early years gave way to steady progress—always slower than desired, with ups and downs, but progress, nonetheless. Some challenges were not obvious at the outset. For example, many regions around the world were very poorly developed in technical diving. Agencies intent on growth seemed to ignore that problem, choosing whoever was available, and regardless of their experience in the discipline, they would soon be teaching.
This decision to promote people with limited experience became especially problematic when it came to Instructor Trainers. People with almost no experience in something like trimix diving were qualifying trimix instructors. Watching this play out in agency after agency, and on continent after continent, was a troubling affair. Conversely, it took many years for GUE to develop and train people of appropriate experience, especially when looking to critical roles, including high-level tech and instructor trainers. At the same time, GUE’s efforts shaped the industry in no small fashion as agencies began to model their programs after GUE’s training protocols. Initially, having insisted that nobody would take something like Fundamentals, every agency followed suit in developing their own version of these programs, usually taught by divers that had followed GUE training.
This evolving trend wasn’t without complexity but was largely a positive outcome. Agencies soon focused on fundamental skills, incorporated some form of problem-resolution training, adhered to GUE bottle and gas switching protocols, reduced insistence on deep air, and started talking more about developing skilled divers, among other changes. This evolution was significant when compared to the days of arguing about why a person could not learn to use trimix until they were good while diving deep on air.
To be sure, a good share of these changes was more about maintaining business relevance than making substantive improvements. The changes themselves were often more style than substance, lacking objective performance standards and the appropriate retraining of instructors. Despite these weaknesses, they remain positive developments. Talking about something is an important first step and, in all cases, it makes room for strong instructors in any given agency to practice what is being preached. In fact, these evolving trends have allowed GUE to now push further in the effort to create skilled and experienced divers, enhancing our ability to run progressively more elaborate projects with increasingly more sophisticated outcomes.
The Future of GUE
The coming decades of GUE’s future appear very bright. Slow but steady growth has now placed the organization in a position to make wise investments, ensuring a vibrant and integrated approach. Meanwhile, evolving technology and a broad global base place GUE in a unique and formidable position. Key structural and personnel adjustments complement a growing range of virtual tools, enabling our diverse communities and representatives to collaborate and advance projects in a way that, prior to now, was not possible. Strong local communities can be easily connected with coordinated global missions; these activities include ever-more- sophisticated underwater initiatives as well as structural changes within the GUE ecosystem. One such forward-thinking project leverages AI-enabled, adaptive learning platforms to enhance both the quality and efficiency of GUE education. Most agencies, including GUE, have been using some form of online training for years, but GUE is taking big steps to reinvent the quality and efficiency of this form of training. This is not to replace, but rather to extend and augment inwater and in-person learning outcomes. Related tools further improve the fluidity, allowing GUE to seamlessly connect previously distant communities, enabling technology, training, and passion to notably expand our ability to realize our broad, global mission.

Meanwhile, GUE and its range of global communities are utilizing evolving technologies to significantly expand the quality and scope of their project initiatives. Comparing the impressive capability of current GUE communities with those of our early years shows a radical and important shift, allowing results equal or even well beyond those possible when compared even with well-funded commercial projects. Coupled with GUE training and procedural support, these ongoing augmentations place our communities at the forefront of underwater research and conservation. This situation will only expand and be further enriched with the use of evolving technology and closely linked communities. Recent and planned expansions to our training programs present a host of important tools that will continue being refined in the years to come. Efforts to expand and improve upon the support provided to GUE projects with technology, people, and resources are now coming online and will undoubtedly be an important part of our evolving future.
The coming decades will undoubtedly present challenges. But I have no doubt that together we will not only overcome those obstacles but we will continue to thrive. I believe that GUE’s trajectory remains overwhelmingly positive, for we are an organization that is continually evolving—driven by a spirit of adventure, encouraged by your heartwarming stories, and inspired by the satisfaction of overcoming complex problems. Twenty-five years ago, when I took the path less traveled, the vision I had for GUE was admittedly ambitious. The reality, however, has exceeded anything I could have imagined. I know that GUE will never reach a point when it is complete but that it will be an exciting lifelong journey, one that, for me, will define a life well lived. I look forward our mutual ongoing “Quest for Excellence.”
See Listings Below For Additional Resources On GUE And GUE Diving!

Jarrod is an avid explorer, researcher, author, and instructor who teaches and dives in oceans and caves around the world. Trained as a geologist, Jarrod is the founder and president of GUE and CEO of Halcyon and Extreme Exposure while remaining active in conservation, exploration, and filming projects worldwide. His explorations regularly place him in the most remote locations in the world, including numerous world record cave dives with total immersions near 30 hours. Jarrod is also an author with dozens of publications, including three books.
A Few GUE Fundamentals
Similar to military, commercial and public safety divers, Global Underwater Explorers (GUE) is a standards-based diving community, with specific protocols, standard operating procedures (SOPs) and tools. Here are selected InDEPTH stories on some of the key aspects of GUE diving, including a four-part series on the history and development of GUE decompression procedures by founder and president Jarod Jablonski.

Anatomy of a Fundamentals Class
GUE Instructor Examiner Guy Shockey explains the thought and details that goes into GUE’s most popular course, Fundamentals, aka “Fundies,” which has been taken by numerous industry luminaries. Why all the fanfare? Shockey characterizes the magic as “simple things done precisely!

Back to Fundamentals: An Introduction to GUE’s Most Popular Diving Course
Instructor evaluator Rich Walker attempts to answer the question, “why is Fundamentals GUE’s most popular diving course?” Along the way, he clarifies some of the myths and misconceptions about GUE training. Hint: there is no Kool-Aid.

As you’d expect, Global Underwater Explorers (GUE) has a standardized approach to prepare your equipment for the dive, and its own pre-dive checklist: the GUE EDGE. Here explorer and filmmaker Dimitris Fifis preps you to take the plunge, GUE-style.

The Flexibility of Standard Operating Procedures
Instructor trainer Guy Shockey discusses the purpose, value, and yes, flexibility of standard operating procedures, or SOPs, in diving. Sound like an oxymoron? Shockey explains how SOPs can help offload some of our internal processing and situational awareness, so we can focus on the important part of the dive—having FUN!

Standard Gases: The Simplicity of Everyone Singing the Same Song
Like the military and commercial diving communities before them, Global Underwater Explorers (GUE) uses standardized breathing mixtures for various depth ranges and for decompression. Here British wrecker and instructor evaluator Rich Walker gets lyrical and presents the reasoning behind standard mixes and their advantages, compared with a “best mix” approach. Don’t worry, you won’t need your hymnal, though Walker may have you singing some blues.

Rules of Thumb: The Mysteries of Ratio Deco Revealed
Is it a secret algorithm developed by the WKPP to get you out of the water faster sans DCI, or an unsubstantiated decompression speculation promoted by Kool-Aid swilling quacks and charlatans? British tech instructor/instructor evaluator Rich Walker divulges the arcane mysteries behind GUE’s ratio decompression protocols in this first of a two part series.

The Thought Process Behind GUE’s CCR Configuration
Global Underwater Explorers is known for taking its own holistic approach to gear configuration. Here GUE board member and Instructor Trainer Richard Lundgren explains the reasoning behind its unique closed-circuit rebreather configuration. It’s all about the gas!

GUE and the Future of Open Circuit Tech Diving
Though they were late to the party, Global Underwater Explorers (GUE) is leaning forward on rebreathers, and members are following suit. So what’s to become of their open circuit-based TECH 2 course? InDepth’s Ashley Stewart has the deets.

Diving projects, or expeditions—think Bill Stone’s Wakulla Springs 1987 project, or the original explorations of the Woodville Karst Plain’s Project (WKPP)—helped give birth to technical diving, and today continue as an important focal point and organizing principle for communities like Global Underwater Explorers (GUE). The organization this year unveiled a new Project Diver program, intended to elevate “community-led project dives to an entirely new level of sophistication.” Here, authors Guy Shockey and Francesco Cameli discuss the power of projects and take us behind the scenes of the new program

Decompression, Deep Stops and the Pursuit of Precision in a Complex World In this first of a four-part series, Global Underwater Explorers’ (GUE) founder and president Jarrod Jablonski explores the historical development of GUE decompression protocols, with a focus on technical diving and the evolving trends in decompression research.