PHOTOGRAPHER
PORTFOLIO: MIKE RALL
OFFSHORE
The deeper secrets of Brothers, Daedalus, and Elphinstone
UNDESERVED DCI
Is it meaningful to use the label or is it escapism?
LIMITED VISIBILITY
The techniques for safe diving in dark or murky waters
Lights are an essential element of the GUE configuration
Sometimes, I find myself yearning for a pause button or even the ability to halt the relentless march of technological progress. My current technology ecosystem, including my computers, smartphone, tablet, and cameras, already exceeds my needs, and I have no demand for more speed, features, or pixels.
As we reflect on the year 2023 in the future, I am confident that it will be remembered as the year when artificial intelligence truly began to permeate our lives. I appreciate the current possibilities AI offers, but I do not need further advancements. Stop. Freeze here, please! However, I am aware that we have only scratched the surface, and AI will undoubtedly have an enormous impact on our future.
Many industries will face challenges due to the disruption caused by these advancing technologies. There are plenty of examples from the last 20 years of market leaders that went out of business within a few years. Where are Blockbuster, Kodak, or Nokia these days?
With the increasing prevalence of AI and related technologies like augmented reality and spatial computing, I firmly believe that authentic and immersive experiences in nature, such as diving, will assume even greater importance in our quest for genuine experiences. It is my prediction that diving will be an even more sought-after experience in the future. I don’t think the diving industry, certifying agencies, or diving communities need to fear a disruptive wave from AI. While advanced technology enhances our capabilities and opens new horizons, it is through authentic experiences in nature that we can ground ourselves and find solace from the digital realm.
The allure of nature lies in its ability to transport us beyond the confines of screens and algorithms, to awaken our senses, and to remind us of our place in the vast tapestry of life. It offers a sanctuary for introspection, a space where we can unplug from the constant stream of information and reconnect with our surroundings.
Diving and exploration provide participants with authentic experiences by offering a unique and immersive encounter with the underwater world, fostering connections with nature, presenting physical and mental challenges, and allowing them to escape from the ordinary, all while building meaningful relationships with fellow divers.
Just to add a meta layer to this editor’s letter and to provide full transparency: it is partly written with the assistance of AI. Who knows? Maybe AI will take over the editing of Quest one day? So be it. I will go diving instead.
Dive safe and have fun!
Jesper Kjøller Editor-in-Chief jk@gue.comEditor-in-chief
// Jesper Kjøller
Editorial panel
// Michael Menduno
// Amanda White
Design and layout
// Jesper Kjøller
Copy editing
// Pat Jablonski
// Kady Smith
Writers
// Dimitris Fifis
// Neal W. Pollock
// Brad Beskin
// Jesper Kjøller
// Kirill Egorov
// Dan Mackay
// Daniel Riordan
// Fred Devos
// Todd Kincaid
// Chris Le Maillot
// Jarrod Jablonski
Photographers
// Kirill Egorov
// Jesper Kjøller
// Julian Műhlenhaus
// Peter Gaertner
// Mike Rall
// Derk Remmers
// Katy Fraser
// Rich Denmark
// Fred Devos
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A look at the benefits of the GUE EDGE sequence and other rituals that helps divers to perform at their best.
One of the most popular liveaboard routes in the Egyptian part of the Red Sea has been the BDE itinerary—Brothers, Daedalus, and Elphinstone. But only a few divers realize that these spectacular offshore reefs are all hiding deeper secrets out of reach of recreational limits.
Skilled divers can adapt using techniques and equipment to overcome visibility challenges. Additionally, specific procedures enable safe diving in limited visibility.
Raised on Durban’s scenic coast in South Africa, Mike developed a deep connection with the ocean. To share its mesmerizing sights, he pursued underwater cinematography and photography. He collaborates with organizations, using his art to raise awareness about marine ecosystems’ beauty and vulnerability.
Divers often blame “undeserved” hits for decompression sickness. Diving physiologist Dr. Neal Pollock debunks this belief, pointing out that other factors impact decompression. Discarding this notion, divers can focus on responsible dive planning and safety.
Diving lights, their integration into the configuration, and the protocols for their usage are essential elements deeply embedded in the philosophy of GUE. Diving lights are built upon two evolving technologies: batteries and light sources. We will shed some light on the subject.
The rewards and hazards of every overhead venture require that dive teams develop a comprehensive yet flexible dive plan well in advance of the first tie-off. In contrast to what the term might suggest, dive planning entails much more than just establishing the intended path of a proposed dive.
Rituals are a part of our lives, from the religious and ceremonial to the everyday and mundane. They can provide us with a sense of structure, comfort, and even safety. For divers, rituals can be especially important, as they can help to ensure a safe and successful dive. One of the most important rituals for divers is the GUE EDGE pre-dive sequence. This standardized pre-dive check helps divers confirm they are prepared for the dive ahead. It is a valuable tool for reducing risk and preventing accidents. Let’s look at the benefits of the GUE EDGE sequence and other dive rituals. We will also look at the psychological impact of rituals and how they can help divers to perform at their best.
The pre-dive procedure is not only about repeating important information about the dive. It also serves as an important ritual that makes everyone ready.
hen the anthropologist Bronislaw Malinowski visited the Trobriand Islands in Papua New Guinea in the early 20th century, he noted the elaborate preparations fishermen would make before setting out to sea. They would carefully paint their canoes with black, red, and white paint, chanting spells as they did so. The vessel would be struck with wooden sticks, the bows stained with red ochre, and crew members would adorn their arms with shells.
Malinowski recorded a long list of ceremonies and rituals the islanders would perform before venturing out onto the open sea. But when the fishermen went out into the nearby calm lagoon, they did not use these rites. Malinowski concluded that the “magic” rituals performed by the islanders were a response to help them cope with the unpredictable might of the Pacific Ocean. Johnson, “The surprising power of daily rituals”, BBC (Sept. 14, 2021)
Rituals hold an important position in our lives. From religious and ceremonial to those daily (and often overlooked) practices that keep our lives on track, most of us regularly practice some kind of ritual.
GUE divers are no stranger to this, as they begin each dive with an important ritual: the GUE EDGE pre-dive sequence. For those unfamiliar: GUE EDGE is an acronym designed to help GUE divers follow a standardized pre-dive check. This review ensures that all team members are ready for the dive, that they all confirm under -
Wstanding of the basic dive parameters, and that their equipment is ready and functioning as intended. It is usually performed prior to entering the water, but it can also be performed at the surface just prior to descent if conditions allow (manageable waves, weak current). The procedure is led by the team leader, with the team members confirming or stating all required parameters.
We can never dismiss the obvious practical utility of GUE EDGE: Each of us has found some key element of equipment out of place on the first “E” (it’s always my drysuit hose—always). The safety that is the hallmark of GUE comes from (at least in great part) detailed attention to and management of the demands of each letter in the acronym, as applied broadly to our diving.
But even practices with substantial utility like GUE EDGE can have a secondary purpose echoing in ritual. To this end, GUE EDGE is more than a simple acronym, and it has value beyond its obvious utility as a risk management and harm prevention tool. This added value lies in how we use it: a requisite, repeated process before each and every dive. GUE EDGE thereby serves a secondary purpose as a series of shared acts, checks, commitments, and acknowledgements that emphasizes the team’s cohesion and readiness for the dive ahead. In this sense, GUE EDGE is an important ritual that GUE divers use to center themselves, inspire confidence, and manifest control. It signals the start of the dive, sets the divers’ minds to tasks at hand, and (at least for many) provides a familiar, calming, and centering routine to shake off anxiety and increase focus.
“To this end, GUE EDGE is more than a simple acronym, and it has value beyond its obvious utility as a risk management and harm prevention tool.
Now, before you go all “Eyes Wide Shut” on me, Quest reader, let’s agree on a few assumptions. I’m not suggesting GUE EDGE holds the station of a “capital R” ritual. Each of us is likely familiar in some regard with some form of ritual, and this proper title is likely best reserved for those practices with, for example, a religious, spiritual, or ceremonial connection. Each major religion has an array of rituals that are keenly practiced by its followers. Governments have rituals like the recitation of the Pledge of Allegiance or Coronation. Social organizations may conduct initiation rituals or other ceremonies for new members.
But more to my point here, each of us likely has a list of less formal rituals that we have weaved into certain regular activities. These “little r” rituals are the structure we add when none may be needed; the things we repeat because they bring us joy, reduce our stress, or make us feel part of something larger than ourselves. Perhaps this is morning coffee and a crossword, a pre-work run, or simply listening to a favorite
podcast on a commute. Perhaps you close your day by reading a few chapters of a good book. Whether you read for pleasure or more formative purposes, this nightly ritual helps to bring closure to your day and prepare your mind for rest. Perhaps it’s a bedtime story with a child or important questions around the dinner table. Each of these important acts has practical value (e.g., teaching a child to read), but our engagement with them has a meta-purpose that exceeds the act itself. It signals the start or the end of our day, it puts our mind in the mode we need for the tasks to come, it reduces stress, and/or it provides a sense of family, unity, or cohesion with others. These are invaluable, and we use rituals daily to achieve these important purposes.
Divers are no strangers to rituals, and GUE has in its culture several rituals that prepare and guide us toward safe, goal-oriented diving. Even less critically, how we pack our gear, don our suits, and even when we use the bathroom be-
PHOTO KIRILL EGOROV
fore the dive is often sequential, rehearsed, and repeated—not just for the practical utility, but because doing it that way makes us feel a certain way that we find valuable to our dive day.
“Ritualistic practices can help to bring a degree of predictability to an uncertain future. They convince our brains of constancy and predictability as ritual buffers against uncertainty and anxiety…” Johnson, supra.
GUE EDGE stands out as perhaps the most universal and consistent dive ritual GUE divers practice. When the team leader gets to the “G”, everyone knows it’s “go time”. Like many rituals, GUE EDGE is symbolic. The repetition of its component parts signals to each teammate the preparedness of the unified team. Shared rituals like GUE EDGE demonstrate the like-mindedness and common values between participants. It reminds the team that each component member is highly trained, practiced, safety-focused, and goal-oriented. Indeed, GUE facilitates the nearly immediate integration of a GUE diver into a GUE team through standardization of equipment, procedures, etc. Nothing signals this more clearly than the GUE EDGE check between divers diving together for the first time: It signals a deeper connectedness that welcomes trust. See Legare and Watson-Jones, “The Social Functions of Group Rituals”, Current Directions in Psychological Science (Jan. 2015).
Scientists and researchers have attempted to measure the impact ritual has on our lives in various ways. “Take a look, for instance, at some of our most cherished cultural and religious rituals.
You’ll notice just how much repetition and scripted rigidity are built into them. This isn’t happenstance; these behaviors fulfill a fundamental psychological need. They give us a sense of structure […]. They convince the brain that things in our world are predictable, ordered, and safe.” Hobson, Ph.D., “The Anxiety-Busting Properties of Ritual”, Psychology Today (Sept. 25, 2017).
Dr. Hobson suggests rituals create certainty through their basic structure, which is compounded over time. “The more we do them, the more meaningful they become, both to us and to others with whom we might share them.” Indeed, the more we run through GUE EDGE, and the more we run through it with the same teammates, the faster our confidence in our abilities and skills grows.
Dr. Hobson’s work distills the power of rituals into three overlapping categories: regulation of (1) emotions, (2) performance goal states, and (3) social connection to others. Hobson, et al., “The Psychology of Rituals” (2017). This is fitting—and GUE EDGE seemingly satisfies all three of these metrics.
The ritual of GUE EDGE isn’t novel. Rituals play an important role in sports and extreme athleticism. “In performance domains, most notably in sports athletics, there is some evidence showing rituals serve a regulatory function. For instance, performing rituals during athletic events, like right before shooting a free-throw in basketball, helps players perform better, especially in highstakes competition and stress. The thinking is that rituals help improve performance because
Brad Beskin has been diving actively for approximately twenty-eight years. He first became involved with GUE by taking Fundamentals in 2002, and then Cave 1 with Tamara Kendal in 2003.
Brad BeskinHe is now a proud GUE DPV Cave diver and is looking forward to undertaking
the GUE technical curriculum in 2023. When he is not diving, he earns his living as a civil litigator in Austin, Texas, and he also finds time to act as Director of Quality Control and the Chair of the Quality Control Board for Global Underwater Explorers.
they mobilize motivational and regulatory states, either through improving concentration, creating physical readiness, or boosting confidence.” Hobson, Ph.D. “Rituals decrease the neural response to performance failure” (2017). And it expands into dynamic corporate and start-up cultures. “In all the […] companies we studied we found leaders making extensive use of ritual. [W]e found that creating or reviving club rituals was almost the first thing that a new coach would do—especially in a team turnaround situation. Smart business leaders do the same…” Guenzi, “How Ritual Delivers Performance”, Harvard Business Review (Feb. 25, 2013).
What dive rituals do you practice to inspire confidence, reduce anxiety, or manifest focus? Does GUE EDGE have this secondary effect on you?
“What dive rituals do you practice to inspire confidence, reduce anxiety, or manifest focus? Does GUE EDGE have this secondary effect on you?
Depending on the circumstances, GUE EDGE can be performed on land or at the surface before the dive.
For a few years now, one of the most popular liveaboard routes in the Egyptian part of the Red Sea has been the BDE itinerary—Brothers, Daedalus, and Elphinstone. But only a few divers realize that these spectacular offshore reefs are all hiding deeper secrets out of reach of recreational limits.
Ithas been 23 years since I first visited Brothers Islands. The reefs are situated so far from the mainland that diving from a liveaboard was—and still is— the only transportation option. But much has happened since: The quality of the diving vessels that are operating in Egypt has changed, and my skills as a diver and underwater photographer have, too.
After my first visit in 2000, I wrote one of my earliest magazine articles, but I had to get images from other photographers, as I had yet to purchase my first Nikonos camera. The liveaboard was neither particularly seaworthy nor particularly comfortable, and it was quite windy during the whole trip, so it was not an
entirely pleasant experience to be on board. I was actually most comfortable underwater. The relentless wind was so strong that the boat rocked violently 24/7, even in the shelter of the reef. Most of the passengers were permanently seasick during the three days at the Brothers Islands. But, to me, it was totally worth it!
I still remember the first dive on Numidia, where I saw my first hammerhead shark while we were holding on to the shallow parts of the wreck in a ripping current. Numidia drops down to 80 m/260 ft, but the region wasn’t yet equipped to supply technical divers. Nitrox was barely available, so it was good old-fashioned air diving on single cylinders. As I said, a lot has happened since.
The super dive at Big Brother’s North plateau involves scootering between the Aïda and the Numidia.
Al Akhawein in Arabic—are the northernmost of Egypt’s off-shore reefs. The two brothers are found about 200 km/125 mi south of Ras Mohammad or 150 km/90 mi southeast of Hurghada, which translates to an eight to ninehour cruise in good weather. The two brothers are situated just fifteen minutes apart and were formed by steep volcanic cones that rise up from the depths. Their position in otherwise-deep waters poses a danger to the shipping traffic through the Red Sea, as it has throughout the ages. Consequently, Big Brother features a 32 m/105 ft tall lighthouse. The British built the lighthouse in 1883 and renovated it in 1993. Today it is operated by the Egyptian Navy and, in the surface interval between dives, you can visit the lighthouse to enjoy the view or buy a Brothers Islands T-shirt. The islands’ isolated location makes them an absolute delicacy, and many divers consider Brothers to be among the best dive sites in the Egyptian Red Sea. The remote position of the two islands, however, is also a disadvantage.
Conservative diving is advised, as help is far away; night diving is not permitted, and diving conditions can be challenging. Experience with diving in currents and competence in shooting an SMB is an absolute necessity.
Fast-forward to 2022: We make the cruise during the night in relatively rough weather (again, it is a bit of a rocky trip). I’m on the deck before the sun rises, curious about where we are and how the wind affects the conditions. If the wind is too strong, it may be too risky to visit the wrecks at the northern tip of Big Brother. In bad weather, it will become too dicey to get back in the zodiacs if something goes wrong. The weather looks alright, however.
Most divers—limited by nitrox’s operating depth of around 30 m/100 ft and the gas volume in a single cylinder—rarely explore anything other than the very topmost parts of the two wrecks located on the northern tip of Big Brother. But we are equipped with rebreathers, scooters, and trimix, so we can go deeper and stay longer.
The British-built lighthouse, now operated by the Egyptian Navy, offers a scenic view and Brothers Islands T-shirts during the surface interval between dives.
The liveaboard operator, Red Sea Explorers, is a specialist in supporting technical diving, and one of the biggest highlights on their northern routes is the legendary four-wreck dive at Abu Nuhas, where the scooters make it is possible to visit Kimon M, Marcus, Carnatic, and Giannis D on the same dive. At Big Brother, you can make another super-dive with two wrecks on the menu. This is what we had planned.
Two-in-one
After exploring and photographing Aïda with an average depth of about 60 m/200 ft, we steer our scooters towards the Numidia . After approximately five minutes on the throttle, we pass the train wheel set that was lost from the deck of Numidia when she hit the reef. We drop down towards the impressive stern at 80 m/260 ft. Numidia presents itself from its best side today, where the visibility is almost infinite. Michel and I let ourselves fall over the edge of the stern to get a good angle for the pictures of Faisal, who is posing like the experienced underwater model he is. I have done this and other similar dives with Faisal so many times that we work almost telepathically together. He instinctively finds the good spots to pose—an important measure, as we must use our 80 minutes efficiently. Soon we be - gin to move up along the impres - sive wreck that lies on a 45-degree slope on the reef. We explore the huge engine room and
swim out of the skylight to begin the almost two-hour long decompression, a penalty for 30 minutes on the two wrecks with a maximum depth of 80 m/260 ft.
With very few exceptions, the wrecks in the Red Sea always rest close to a reef. It makes sense, as the reefs typically sealed the fates of the ships in the first place. Technical divers who do not like long decompressions in open water, and who are equally bored at the sight of an ascent line, will be happy when decompressing after a wreck dive in the Red Sea. The two-hour decompression on Big Brother’s steep walls is almost a reward. We glide slowly back toward the south plateau where our mothership, M/V Tala, is waiting. The scooters get a break as the current gently carries us back.
The boat is fully booked on this trip. My wife and I are from Denmark, and a very pleasant group of Norwegians makes up most of the guests. There are also a couple of Lebanese divers, a Belgian, and an Egyptian. In addition to the two competent guides, Red Sea Explorers’ founder, Faisal Khalaf, is joining the trip, and he has invited his mother.
If you have ever been on one of the vessels in the Red Sea Explorers fleet, you will have learned to appreciate the family atmosphere on board. You feel as if you are traveling with a group of friends and relatives and not at all like a charter tourist.
“Numidia presents itself from its best side today, where the visibility is almost infinite.
It was only when I zoomed in to check the sharpness after the dive that I spotted the longnose hawkfish on the railing at a depth of 80 m/260 ft.
DAEDALUS REEF (Abu Kizan, in Arabic) is 400 m/1,312 ft long, 100 m/330 ft wide, and located approximately 90 km/55 mi from Marsa Alam on the mainland. There is a small artificial island at the center of the reef supporting a lighthouse built by the French in 1863 during the construction of the Suez Canal. The lighthouse was rebuilt in 1931. The picturesque tower is 30 m/100 ft high and still active. It is run by the Egyptian Navy, and they welcome visitors.
Daedalus Reef is well-known for frequent hammerhead shark sightings and its stunningly beautiful walls with an abundance of corals. But, Daedalus also has a secret in the deep.
Even though it rests on 100 m/330 ft, the Zealot wreck is perhaps not such a big surprise after all, as the large field of debris and wreckage that spreads over the reef reveals its location. But, I’m sure many divers have swum past the debris field without knowing that there is a wreck deep down below. The debris is scattered over a larger area, so it can be difficult to find the Zealot. Our descent is a little bit off the mark, and we end up cruising 300 m/1,000 ft at 60 m/200 ft depth with the scooters before we finally see the contours of the ship. We wasted valuable bottom time in our search of the wreck, but our rebreathers provide unmatched flexibility, and we are only limited by how much decompression we are willing to pay at the other end. We have enough breathing gas to last us six or seven hours.
If you have dived the Carnatic at Abu Nuhas, you have a very good impression of what type of vessel Zealot is. However, probably only a fraction of divers have been here compared to Carnatic, which rests at 20 m/66 ft. Zealot appears somewhat more damaged; the wreck is scattered over a larger area, and it is difficult to form an overall overview. But the helm, the propeller, and the two anchors offer some waypoints. After spending about 15 minutes on the wreck, aver-
aging 95 m/310 ft depth, we are approaching the maximum decompression we have agreed to before the dive and it is time to leave the site.
As we approach the last and longest decompression stop at 6 m/20 ft, where we are supposed to spend over an hour, we can feel that the surface has become rather turbulent, and it is awkwardly difficult to stay stable at our target depth. If we swim out from the reef, the surge from the surface is less noticeable, but it is unsafe to stay where the zodiacs rush up and down the reef taxiing divers to and from the dive sites. Close to the reef, the surge is taking us for a ride up and down—not a good way to do deco. On a rebreather you cannot fine-tune your buoyancy with your breath, so it’s hard work to compensate for surge.
Since the 60-minute deco at 6 m/20 ft will be uncomfortable at best and will feel like an eternity of hard work, I look for a solution. A rebreather is operating on a constant partial pressure of oxygen (pO2). The advantage is that, during decompression, you don’t necessarily have to be at a certain depth, as long as you maintain your pO2. I find a cave in the reef at 7 m/22 ft—it’s big enough to accommodate the three of us—but there is still a strong surge when the water flows in and out of the cavity; it is probably that very water movement that has carved out the cave through the centuries. I have to press my arms and legs against the rock to maintain position, but we can rest pretty comfortably while the minutes tick away. Necessity is the mother of invention. Finally, it’s time to swim out of our temporary habitat and shoot a bag to the surface. We send up our bailout cylinders to the zodiac that has stayed with us during the entire dive. It is almost dark when we finally surface after almost three hours on our rebreather loops.
Hammerheads and oceanic whitetips are commonly spotted around Daedalus, especially during the summer months.
Nowadays, we dive the Zealot using rebreathers. However, when I first started diving the wreck 15 years ago, we still used open-circuit equipment.
The llghthouse on Daedalus was build in 1863 during the construction of the Suez Canal. It was reconstructed in 1931 and remains operational.
“Daedalus Reef is wellknown for frequent hammerhead shark sightings and its stunningly beautiful walls with an abundance of corals. But, Daedalus also has a secret in the deep.
Technical diving on Red Sea reefs provides a beautiful adventure, allowing you to appreciate the mesmerizing marine life during the deco stops.
On air, divers, affected by nitrogen narcosis may imagine the square rock as a pharaoh’s sarcophagus. However, with a more sober mindset during a trimix dive, it becomes clear that it is just a large square rock.
ELPHINSTONE REEF (Sha’ab Abu Hamra in Egyptian) is located close to the coast about 30 km/20 mi north of Marsa Alam. The reef is about 500 m/1,640 ft long from north to south. The spectacular walls drop vertically into the depths and the often-strong currents can be very unpredictable. At the northern end, a long, narrow plateau extends far from the main reef. At the end—at about 35 m/115 ft depth—there is a huge crack in the reef as if a giant had cleaved it with an axe. This is a good place to hang for a while to look for sharks. The southern plateau is somewhat smaller, but a few cleaning stations attract thresher sharks, mantas, and other big game. Close to the surface along the reef
or under the boats at the southern end, it is very common to meet the curious and sometimes a little bit too frisky Carcharhinus longimanus—the oceanic white tip shark.
Robert Moresby, an officer in the Indian Navy, reportedly baptized the reef with its English name in 1830 after Mountstuart Elphinstone (1779-1859) who had just retired from his position as Governor of Bombay for the East India Company (1819-27). There are no wrecks at Elphinstone—with its location close to the coast, the reef lies far from the sailing routes through the Red Sea. It has, therefore, not been necessary to establish a lighthouse. But Elphinstone still hides another deep secret.
When divers take a technical diving approach to Elphinstone, they open up a whole new world below 30 m/100 ft. Under the southern plateau of Elphinstone, there is a big hole in the reef— The Arch. Admittedly, in the old days, I used to dive under the Arch on air. (Don’t tell anyone!) It was before I knew better and before I had the opportunity to breathe trimix. It was foolish, as passing through the Arch forces you to go to almost 60 m/200 ft! But with rebreathers, scooters, trimix, and the right decompression gases, it is a completely different experience.
On the bottom, just below The Arch, lies a large square rock. Divers who have been under The Arch on air (and, consequently, are narced stupid) have imagined that the square rock was a pharaoh’s sarcophagus. But, with the more sober and clinical mindset that characterizes a trimix dive, we can clearly see that the large square rock is, in fact, just… a large square rock.
The stunning Gorgonian sea fans, the intriguing sarcophagus, and the heavenly light above make for photogenic subjects.
Most of the liveaboards are moored in the sheltered areas on Elphinstone’s south plateau, and from there it is easy to jump into the water and drop directly beyond the south plateau that stretches away from the reef. On top of the plateau, most divers who have visited E-stone look for big game at the cleaning stations. But, we have a different agenda. We follow the edge of the plateau at about 35 m/115 ft while I’m scouting for The Arch deep below us. A glare from below reveals the big hole in the reef, and we drop down and explore The Arch and its surroundings. The enormous Gorgonian sea fans, the sarcophagus, and the light from above are all very photogenic. We have planned 20 minutes of bottom time; it’s a short dive on a rebreather, but we are accompanied by a relatively inexperienced tech diver on open-circuit, so we respect her limits. After taking lots of pictures under The Arch, we begin the ascent and look forward to a long Elphinstone dive while decompressing after our deep exploration.
Monkey diving in shallow water around Elphinstone is a great way to spend the afternoons.
Recreational scuba diving takes place around the world in all kinds of environments. The widely divergent water conditions—from crystal clear to dark and turbid—create significant variations in visibility.
Regardless of these varied settings, a wellrounded diver should be able to adjust to the underwater environment by using appropriate techniques and equipment to overcome visibility challenges. Some specific techniques can prevent reduced visibility; for example, divers can learn to position themselves, move with greater precision, or hold still in areas where sediment disturbance greatly impacts visibility.
In cases where visibility is limited from the start, such as during night dives or while exploring turbid waters, divers can use certain equipment or procedures to dive safely.
“The light supports effective communication over reasonable distance and/or during limited visibility dives while also greatly illuminating the area around divers even when the conditions are extremely dark.
The primary light facilitates team coherence in dark environments or in situations with limited visibility.
Diving in limited visibility can present unique challenges, including difficulty with navigation, risk of team separation, disorientation, and difficulty in controlling buoyancy and/ or ascent rate. The appropriate equipment and techniques address all of these conditions.
GUE’s standard equipment configuration was initially developed for diving in areas with limited visibility. This standard configuration, therefore, provides a great start for most divers. For example, most GUE divers will use a high-intensity primary light for most or all of their diving activity. This light supports effective communication over reasonable distance and/or during limited visibility dives while also greatly illuminating the area around divers even when the conditions are extremely dark. These lights are also focusable, so they can be adjusted in waters that contain suspended particles. A tighter beam allows the diver to limit backscatter (which occurs when a light reflects off sediments) and increases communication abilities at great distances. Meanwhile, being able to de-focus the beam allows divers to get a better view of the surrounding environment. A lighthead that allows the diver to switch between a narrow and a wide beam offers the best of both worlds.
A GUE diver uses what is called a Goodman handle on their primary light. This offers the ability to use the light while leaving one’s hands free for other uses. This is accomplished with a light that sits on top of the diver’s hand, almost like a glove, and is supported by a grip nestled in the palm of the hand. The primary light battery should be at least sufficient to power the light beyond the anticipated duration of the dive—including possible extensions to the dive time—and also for limited use while on the surface. GUE divers normally prefer a light with approximately 50% more time than needed, although they might adjust this factor depending
on the type of dive and the experience level of the divers involved. LED technology combined with advances in battery technology offers impressive light intensity with a relatively small lighthead over many hours.
Diving in reduced visibility environments also requires a secondary or backup light. These lights are typically smaller and have reduced light intensity, but they should still produce a reasonable amount of light. One can gauge the intensity of an acceptable backup light by testing their comfort in relevant environments while using only this light. If the light is not sufficient for comfort and communication, then divers should consider another option. Should problems arise with the primary dive light, divers can maintain reasonable visibility and communication with their team using a backup light. Divers should carry at least one backup light and store it in a convenient and secure location that reduces the risk of loss or entanglement—like the shoulder strap connecting the top and bottom of a diver’s backplate.
Reliability should be the main characteristic of a backup light. Other important features include a minimalist design with fewer failure points or possible water intrusion points. Turning the light on and off is usually accomplished by twisting the lighthead, a simple mechanism that reduces some of the complexity of switches. Backup lights should be powered by non-rechargeable batteries since they are designed with a long shelf life and provide a more reliable output when compared to rechargeable batteries, whose discharge has a tendency to decline over time, especially if not recharged regularly.
Small strobe lights can also be useful while diving in reduced visibility environments. In situations where it is important for the team to return to a specific point, strobes can be used to indicate the exit point or the ascent line; they can also make a diving buoy visible at the surface during night dives.
In situations with appropriate water clarity, chemical lights sticks (Cyalume) can also be used as markers.
Divers should verify that they can read all gauges in reduced visibility or dark environments. All instruments should be luminescent or use some form of self-illumination (backlight) so they can be read easily. Most gauges typically remain bright for a couple of minutes after being illuminated for a few seconds with a reasonably bright light, and the team can always refresh this illumination with their handheld lights. Bottom timers and dive computers normally have their own backlights, which makes their screen easily readable in a variety of conditions. Divers should practice with these instruments and ensure they do not set the gauges to have very high illumination during dives. Looking into a very bright gauge (or any other light) can be uncomfortable or even dangerous when the pupils are dilated because of the dark surroundings. This action also temporarily reduces divers’ ability to see around them, so using a very bright gauge will be a continual source of distraction, negatively affecting vision throughout the dive.
A few other key pieces of equipment include a navigation line, navigation markers, a compass, and, for some dives, a navigation computer. A navigation line can be deployed from a reel or a spool, which is chosen based upon the amount of line needed and the intended use by the team. Use of reels and spools can be challenging in the beginning and lead to entanglement or team confusion due to task loading and increased stress. Divers should seek training to support use of these tools. Diligent training is critical for diving in overhead environments since they can pose additional risks. Some divers might use various line marking tools, such arrows and cookies, to mark areas or directions of travel. Compasses can also help divers ensure proper directions of travel, track their path, and return along the same or similar direction. These
Surface light sources, like powerful boat lights, assist divers with navigation in dark or lowvisibility environments.
various tools might also be useful when used together with dive area maps. Finally, some divers might consider evolving technological support that allows divers to track one another as well as a boat or other point of entry. These tools are becoming more affordable and more reliable and will likely one day be as common as smartphone map navigation.
Detailed dive planning, solid navigation skills, and adherence to team diving procedures (such as those advocated by GUE) greatly reduce the risks associated with diving in reduced visibility environments. When diving in such conditions, the following guidelines greatly enhance team capacity while also increasing safety and fun for all involved.
Team goals should be simple, realistic, and consider the capacity of individual team members as well as their experience in reduced visibility environments. The team should be careful to establish clear responsibilities for each team member, including their position in the team and the way the team will orient while diving. For example, will the team be in a single line or side by side? Knowing the formation ahead of time, as well as one’s place in this plan, will greatly reduce risk of confusion or loss of a team member. The team should also discuss the appropriate distance between team members, which is based upon the visibility and team member experience. Diving about one arm-length apart notably reduces risk of separation and makes communication much easier. Procedures for managing a possible team separation should
also be made clear so that all members understand how they are expected to act if they are lost or should they notice a missing team member. Finally, all team members should be careful to avoid forcing or coercing fellow divers into activities that make them uncomfortable.
When a team member seems nervous about the visibility or suggests calling the dive because conditions appear to be worse than expected, the rest of the team needs to honor that person’s discomfort and avoid making any disparaging comments toward them.
All equipment should be well maintained and thoroughly checked during the pre-dive equipment procedures. Ideally, the team will be using a standard configuration so that all members are similarly configured; all equipment should be checked and its location verified, with differences between team members noted for everyone to consider. Diving in limited visibility conditions can notably increase stress, foster problems, and greatly complicate emergency situations. Therefore, divers should take extra care that their team members are aware of and can easily locate all useful equipment if needed.
Dive exposure plans should be adjusted in a conservative direction while considering depth, bottom time, and gas used. This is especially true while the team gains experience in challenging diving conditions. The increased risk of team separation and the complexity of performing a slow ascent or decompression stops in reduced visibility dictates avoidance of overly aggressive profiles while engaging in recreational diving.
Team members should also consider the choice of breathing gas during low visibility dives. Reduced visibility can encourage psychological stress, which may in turn influence respiration, leading to increased levels of carbon dioxide. Increased CO2 and heightened stress from re-
duced visibility can further enhance the effects of gas narcosis, negatively affecting awareness. In these cases, divers should consider using a gas with helium, such as triox 30/30, as it reduces many of the above risk factors. Elevated stress during low visibility dives can also increase gas consumption and necessitate adjustment of planned turn pressure. Increased awareness and accurate gas tracking will allow the team to modify the dive plan before increased gas consumption becomes an uncontrolled risk.
Intensified current, increased boat traffic, cold water, and obstructions in the water are some other environmental factors that should be considered, as they enhance risk and increase stress levels, especially in a low visibility environment. Monitoring environmental conditions and maintaining awareness supports early detection of any developing problems in the environment.
Navigation, communication, and control are three of the most important skills for diving in limited visibility environments. Divers should employ a combination of natural and compass navigation. Less experienced teams should avoid night diving in areas where they have no prior experience, or they should at least join divers with previous experience. Knowing the dive site and having good natural navigation references supports fun and safety during a night dive. As divers build experience, they can slowly expand the area they explore, allowing the team to become familiar with environmental references before moving further from the entry/exit point. The same guidelines apply while diving during the day in areas of limited visibility. The team should gradually expand the area explored, making sure they have adequate navigational references to safely return to the exit point.
Compass bearings, distance covered, course followed, and even a rough map of the most important landmarks can be noted to wetnotes, aiding the team in its navigation.
Diving in reduced visibility conditions also necessitates the use of clear and unambiguous communications among team members. Proper use of a diving light in both passive and active communication is important, as it might be difficult for team members to clearly see each other. Passive communication results from divers seeing the presence of the light from other team members, which helps to keep the team together. Active communication includes signals with the light such as “ok” by making a circular action with the light or “attention” by moving the light back and forth steadily, or even “emergency” by waiving the light more aggressively. Hand signals should be illuminated in a way that makes them visible, while at the same time assuring that the light beam doesn’t blind the rest of the team. Team members with weak or broken lights should be placed between other team members. Touch contact can even be used in very low visibility whereby a diver can hold the elbow of their team mate, keeping the team together and/or helping to guide confused divers.
Having precise control over one’s body while diving is a skill that is built over time and with practice. GUE training focuses heavily on developing these skills so that divers can move any part of their body in a precise and conscious way. Exceptional control may be rarely needed in most diving if divers remain in appropriate environments and dive within their limits. However, good control always supports a bet -
“Even divers with good stability, efficient propulsion, and solid buoyancy control can struggle in poor visibility given a lack of clear visual references. The disorientation can be especially prominent during a vertical ascent to the surface.
ter diving experience including more fun and safety along the way. As dives become more complicated and environments become more challenging, a diver’s level of precision should likewise improve, and precision becomes progressively less optional. Being in control while underwater involves 1) a diver’s position in the water column adjusted by changes in buoyancy, 2) maintaining stability by learning to minimize unnecessary movement, and 3) moving efficiently through the water without disturbing sediments. Each of these aspects can greatly affect the way divers move through the water and usually have the greatest effect on the visibility immediately around a diving team. Many divers make the visibility somewhat or a lot worse due to inattention to these three aspects. Even divers with good stability, efficient propulsion, and solid buoyancy control can struggle in poor visibility given a lack of clear visual references. The disorientation can be especially prominent during a vertical ascent to the surface. In this case, divers often ascend too quickly or even go up and down as they rise too shallow and over-correct, sinking too deep. In aviation, an activity with many similarities to diving, pilots are trained to overcome these difficulties by focusing on the aircraft
instruments, as their senses will most probably be mistaken. With practice, this tactic can help divers as well. Ascending slowly with planned stops or waypoints during the ascent can support the accurate reading of instruments while anticipating buoyancy changes and supporting a controlled ascent with no visual references.
The equipment, procedures, and techniques divers use have a substantial impact on their comfort, not to mention the type of environment they will be able to safely explore. By developing a strong foundation of quality equipment standardized within the team, one can avoid confusion and simplify all diving activity. Meanwhile, appropriate procedures and techniques are a huge asset in managing a wide variety of environments. To some extent, all these aspects are somewhat refined by the environment explored. However, GUE has carefully chosen training and equipment that supports a vast array of diving environments with particular attention to enabling divers to manage more stress with less anxiety and more comfort. This is very true while diving in reduced visibility environments as well as a variety of both simple and challenging environments.
Born in Athens, Greece, Dimitris Fifis started diving in 1991 and became an instructor in 1998. In 2009, after 23 years of service in the Greek Navy (most of them in the aviation branch), he retired and decided to pursue a fulltime career in diving. Since then he has managed diving operations in various diving centers in Greece as well as on mega-yachts. Dimitris discovered GUE
in 2007 and never looked back. He currently lives and works in Dubai, and is involved in various wreck exploration and underwater filming projects in the area. Because of his strong interest in increasing dive safety through quality education, he also produces training videos for GUE.
rowing up on the picturesque coastline of Durban, South Africa, Michael developed an intimate connection with the ocean. Eager to share the mesmerizing underwater sights he encountered, Michael decided to persue underwater cinematography and photography.
After moving to Dubai in 2008, he soon established himself as a versatile visual artist and honed his craft until 2020, when he co-founded Base Films alongside his business partner Richard, creating a company that specializes in underwater and aerial imagery.
Michael’s quest for knowledge led him to immerse himself in numerous diving techniques but favoring freediving while shooting whenever possible.
While filming documentaries, feature films, and TV commercials, Michael expertly handles cinema cameras from brands like RED and ARRI
Gexpertly housed by his trusted Gates housings. One of Michael’s greatest assets lies in his ability to adapt to different photographic styles. His artistic vision shines through whether he’s capturing underwater landscapes, intricate macro details, or graceful underwater poses with models. His portfolio stands as a testament to his versatility, presenting an array of colors, textures, and emotions extracted from beneath the water’s surface.
Michael demonstrates an unwavering commitment to environmental conservation, collaborating with conservation organizations. Through his lens, he helps raise awareness about the delicate nature of marine ecosystems, emphasizing their beauty and vulnerability for future generations. Michael’s passion for underwater cinematography and photography remains ceaseless. He continually wants to explore new underwater environments and capture the enigmatic underwater realm. Through his inspiring imagery, he invites viewers on a profound journey to experience the captivating depths, reminding us of the profound beauty concealed beneath the surface of our planet’s waters.
www.michaelrall.com
www.basefilms.ae
TITLE Potato Grouper LOCATION Aliwal Shoal, South Africa
CAMERA Nikon D850
HOUSING Nauticam D850
LENS Nikon 16-35mm f/4
EXPOSURE 1/250, f/11, ISO1250
FLASH 2 x Ikelite DS161
Strobes
TITLE Wonderpus LOCATION Anilao, Batangas, Philippines
CAMERA Nikon D850
HOUSING Nauticam D850
LENS Nikon 60mm f/2.8 Macro
EXPOSURE 1/250, f/18, ISO 500
FLASH 2 x Retra Pro Flash
TITLE Green Turtle LOCATION Nosy Be, Madagascar
CAMERA Sony A7IV
HOUSING Marelux A7IV
LENS Sony 12-24mm f/2.8
EXPOSURE 1/200, f/11, ISO400
FLASH None
TITLE
LOCATION NEOM, Saudi Arabia
CAMERA Nikon D850
HOUSING Nauticam D850
LENS Nikon 105mm f/2.8 Macro
EXPOSURE 1/200, f/16, ISO400
FLASH 2 x Retra Pro Flash
TITLE Freediving Photographer
LOCATION NEOM, Saudi Arabia
CAMERA Nikon D850
HOUSING Nauticam D850
LENS Nikonos RS 13mm f/2.8 Fisheye
EXPOSURE 1/800, f/10, ISO1000
FLASH None
TITLE Great White Shark
LOCATION Guadalupe Island, Mexico
CAMERA Canon 5DIII
HOUSING Subal 5DIII
LENS Canon 16-35mm f/2.8
EXPOSURE 1/400, f/8, ISO320
FLASH None
TITLE Rajan the Swimming Elephant
LOCATION Havelock, Andaman Islands
CAMERA RED
HOUSING Gates
LENS Nikonos RS 13mm f/2.8 Fisheye
EXPOSURE 1/100, f/10, ISO800
FLASH None
TITLE Cenote Taj Ma Ha LOCATION Tulum, Mexico
CAMERA Canon 5DIII
HOUSING Subal 5DIII
LENS Canon 16-35mm f/2.8
EXPOSURE 1/100, f/5.6, ISO4000
FLASH None
TITLE Freediving Model
LOCATION Deep Dive Dubai, UAE
CAMERA Sony A1
HOUSING Marelux A1
LENS Sony 16-35mm f/2.8
EXPOSURE 1/160, f/5.6, ISO4000
FLASH None
CAMERA Nikon D850
HOUSING Nauticam D850
LENS Nikon 105mm f/2.8 Macro
EXPOSURE 1/250, f/22, ISO 100
FLASH Retra Pro Flash
Divers still seek comfort in the notion of the “undeserved” hit to explain unexpected incidents of decompression sickness. “Hey, my computer said I was fine.” NOT. Here diving physiologist Dr. Neal Pollock exposes the fault in this notion. While decompression algorithms take into account a diver’s profile, i.e., time
and pressure, there are a multitude of factors that can potentially impact divers’ decompression, as the author explains. Once divers reject the escapism that accompanies the “undeserved” label, they can get on with the important business of diving and giving adequate consideration to their deco planning.
Dgenerally speaks more from an emotional perspective than a rational one. The driving factors are typically faith in imperfect tools and a desire (conscious or unconscious) to shift responsibility.
Decompression algorithms rely almost exclusively on pressure and time data to predict effects. Enticing pictures can be painted on the authority of any algorithm, but the reality is that all rely on limited input to interpret complex situations for people who are not uniform. Modern decompression models are important constructs that can help us to dive safely, but the products are rudimentary from a physiological perspective, without sufficient sophistication to deserve unquestioned trust.
The dive profile is almost certainly the most important determinant of gas uptake and elim-
the variables that can influence outcomes (Pollock 2016). Instead, algorithms rely on simple measures and mathematical bracketing with the hope of covering the contributing factors. The problem is not in doing this; the problem is in being surprised when the outcome is not what was expected.
Decompression safety is influenced by a multitude of factors, variably related to the dive and the diver.
Accepting that the dive profile is the most important determinant of decompression risk, there are additional factors that can also have dramatic effects. Exercise is one of these. Predive exercise may have complicated effects on the subsequent diving exposure. Exercise during the descent and bottom phase will
increase inert gas uptake and the resulting decompression stress. Mild exercise during the ascent and stop phase can promote inert gas elimination and decrease the resulting decompression stress, but excessive exercise can promote bubble formation and increase decompression stress. Post-dive exercise is likely to increase decompression stress in all cases. Practically, while the concepts are clear, the definition of meaningful thresholds for “mild” and “excessive” exercise is difficult at best, and quantifying real-time effects far exceeds current capabilities.
Thermal state is another potentially dramatic factor (Gerth et al. 2007). Being warm during the descent and bottom phase can substantially increase blood flow and delivery of inert gas to the periphery and increase the subsequent decompression stress. Being cool during the descent and bottom phase can decrease inert gas uptake and decrease the subsequent
Moderate exercise during stops aids inert gas elimination and reduces decompression stress, while excessive exercise promotes bubble formation and increases stress.
decompression stress. Being cool during the ascent and stop phase will inhibit inert gas elimination and increase the subsequent decompression stress. Being moderately warm during the ascent and stop phase can promote blood circulation to the periphery and increase inert gas elimination, but excessive heating of peripheral tissues in this same phase can promote bubble formation as heating decreases the solubility of inert gas, effectively increasing the decompression stress.
Again, as with exercise, it is extremely difficult to identify meaningful thresholds for thermal state at different points in a dive, and quantifying real-time effects is not within current capabilities. It is certainly clear that the ambient temperature measured by a dive computer can have little correlation to the thermal status of the diver, and any thought that this information informs decompression models in a meaningful way is misplaced.
The wild card of individual (“predisposition”) factors further highlights the challenges unmet in current decompression models. Not only are these parameters not measured, but it is also unclear how the information could practically guide the risk assessment at this time if available. While the importance of these factors is hard to assess, it is also noteworthy that some, most often dehydration, may be used as scapegoats to explain away decompression sickness (DCS).
A state of dehydration can adversely affect circulation, potentially impeding inert gas elimination, but this almost certainly has much less impact than the dive profile, exercise, or thermal state in many cases. The impact is also not
as straightforward as making it a blame agent might imply. For example, if a state of dehydration impairs inert gas elimination during the ascent and stop phase to increase decompression stress, might it not also decrease inert gas uptake during the descent and bottom phase to reduce the decompression stress?
Sound levels of hydration are good for general health and probably for decompression safety, but a state of dehydration in no way guarantees an outcome of DCS, just like a good level of hydration in no way guarantees an outcome of no DCS. The blame directed to dehydration is probably related to the observation that DCS can be accompanied by clinically important fluid shifts. This, though, is more a consequence of the disease than a cause.
The rest of the predisposition factors offer similar challenges. Physical fitness appears to confer some protection against decompression stress, but the quantification of such effects is not yet possible. A history of DCS can go either way, with persons prioritizing blame-shifting over understanding or behavioral changes having a higher risk of repeat events, and persons improving understanding and moderating risk factors having a lower risk of repeat events. Increasing age is a risk factor, but the partitioning of chronological vs. physiological age still needs to be worked out, as does the interaction between age, physical fitness, and biological health.
Women might have a slightly higher physiological risk, particularly during the first half of
their menstrual cycle, but this is likely largely (or more than) mitigated by sex-based differences in risk tolerance and practices. The norms and practices of a buddy can affect individual risk either positively or negatively. Circulation issues include state of hydration, the presence of a patent foramen ovale (PFO), and possibly old injury sites that disrupt circulatory pathways. The presence of a PFO is likely only able to become important in decompression stress if bubbles are present, which will depend on a host of other factors. Biological health elements are likely to offer interesting insights in the future, but the ability to assess and understand them exceeds current capabilities.
The major point here is that there are a lot of unknowns and half-knowns that make it important to not expect any decompression algorithm to describe truth. They offer a first-order approximation of risk. They provide what might be reasonable guidance within a wide swath of possible error. Staying within guidelines does not guarantee safety. The goal should be to plan for the possibility of suboptimal elements, perhaps several of them, that could influence outcomes.
Divers often address the recognized shortcomings of dive-computer-based decompression models by altering conservative settings and/ or practice. Those who feel they are bends-resistant may push the limits; those who prefer greater peace of mind may add buffers. One of the additional challenges is that not all practices put forward to enhance conservatism will act in that way. The best example of this is probably deep stops. The concept of stopping deep to minimize bubble formation was enticing but flawed. Stopping too deep will certainly minimize the possibility of bubble formation at that point, but at a point when it would never reasonably be expected for bubble formation to occur. The problem is that the time at the deep stop depth allows any tissue that is not fully saturated to take up more inert gas. The additional uptake creates increased decompression stress as the diver ascends. The concept was well intended, but the impact was counterproductive.
One of the conservative settings that is intuitively simple is gradient factors. The M-value describes a theoretical limit of supersaturation that a tissue can tolerate before problematic levels of decompression stress develop. This limit is another first-order approximation of risk, with no guarantees of safety if staying within the limit. Gradient factors (GF) simply tailor limits to a different percentage of the M-value. GFs are typically presented as two values, GF low and GF high, presented as GFlow/GFhigh. Those who believe in deep stops may choose a GFlow less than or equal to 20%. Those who do not believe in deep stops will likely choose a GFlow equal to or greater than 30%. Those who feel confident in their overall ability to tolerate decompression stress might choose a GFhigh in the 85% range. Those who want to add more buffers to protect against unknowns and surprises might choose a GFhigh less than or equal to 70%.
Determining whether a case of DCS should be considered “deserved” or “undeserved” is problematic when prescribed limits are based on incomplete data and when they can be altered by a variety of settings. The argument, “My computer said it was okay!” holds little if any weight. A better approach is to focus on the fundamentals. The first fundamental is to consider when DCS is a possibility. As a rough rule of thumb, any dive within the traditional recreational range (40 m/130 ft) that is approaching half the US Navy no-decompression limit carries a non-zero risk of DCS. Similarly, pretty much any dive deeper than the traditional range carries a non-zero risk. “Non-zero risk” repudiates the claim of “undeserved.”
Once the possibility of DCS has been accepted, the most productive deliberation includes an honest assessment of all of the risk factors that may have contributed to the outcome. While trying to pin the blame on one modifiable risk factor can be comforting, it probably does much less to ensure future safety. There are many effects that cannot yet be quantified, but the risk potential can be recognized. Focusing on any one variable can discourage a more honest appraisal of the possibilities.
DCS symptoms may develop due to frank violations of accepted practice, but many cases are shrouded in ambiguity. An honest and objective assessment will almost certainly improve understanding and future outcomes more than claiming an “undeserved hit” will. It is unlikely that any two exposures will truly be identical, either for two divers sharing one dive or one diver repeating a given dive. Subtle differences can accumulate to have a meaningful impact. These differences coexist with the probabilistic nature of decompression stress; a safe outcome experienced once, or several times, may not guarantee the same for all future exposures.
Once all reasonable contributing factors have been considered, some room should be left for doubt. Appreciating the knowns, the unknowns, and the complexity of interactions can promote thoughtful practice without frustration. Practices can be optimized without guarantees. The first step is getting rid of the escapism that accompanies the “undeserved” label.
Neil Pollock, PhDNeal Pollock holds a Research Chair in Hyperbaric and Diving Medicine and is an Associate Professor in Kinesiology at Université Laval in Québec, Canada. He was previously Research Director at Divers Alert Network (DAN) in
Durham, North Carolina. His academic training is in zoology, exercise physiology, and environmental physiology. His research interests focus on human health and safety in extreme environments.
• Cultivates, integrates, and expands essential skills required for safe technical diving
• Teaches you how to prevent, identify, and resolve problems
• Addresses the potential failures associated with twinsets
• Introduces accelerated decompression strategies, single stage diving, and the use of helium to minimize narcosis
THIS ARTICLE SERIES IS BASED ON THE GUE PUBLICATION
DRESS FOR SUCCESS BY DAN MACKAY
ADDITIONAL TEXT BY JARROD JABLONSKI PHOTOS HALCYON DIVE SYSTEMS & JESPER KJØLLER
Diving lights, their integration into the configuration, and the protocols for their usage are essential elements deeply embedded in the philosophy of GUE. While certain equipment components have remained largely unchanged over the years—for instance, many divers still rely on the same pair of rubber fins and the steel backplate they invested in two decades ago—diving lights are built upon two evolving technologies: batteries and light sources. Let’s shed some light on the subject.
Diving lights provide not only the main source of illumination during diving operations but are also an effective means of diver communication.
The two common styles of diving lights are canister and cordless. The canister light is worn on the diver’s right-side waist with a cord that connects to the lighthead. This light is popular with technical, cave, and overhead divers because it has extended burn time and flexibility; it can be used with different lightheads, and it also functions to power heat for a drysuit.
Cordless lights, on the other hand, attach directly to the battery, which reduces complexity, risk of cord entanglement, and configuration challenges (particularly in sidemount diving when a hip-mounted light is difficult and cord routing problems can occur with butt-mounted canisters).
During their diving careers, tech and cave divers should develop familiarity and proficiency with both types of lights and, should the need arise, be skilled in managing a hip-mounted canister with a light cord.
When selecting a diving light, divers should look for a compact battery pack with an appropriate burn time for the planned dives. The lighthead should have a Goodman-style handle for easy management. If using a hip-mounted canister, ensure that the cord is long enough to reach
from the right hip to the left hand without excess length. The primary light should provide enough burn time to complete the entire dive, with some reserve remaining. As a general rule, having 1.5 times the anticipated burn time is a good approximation. It is also beneficial to choose rechargeable batteries to minimize waste and allow for frequent use. Divers using cordless lights should be particularly aware of maintaining sufficient burn time due to the reduced energy density of these battery packs.
A clip should be fixed permanently to the left side of the Goodman handle where it can be trapped by the diver’s left thumb during use, reducing the risk of entanglement when managing guidelines.
A loop should be fixed at the rear of the lighthead, allowing a double-ender clip to be temporarily attached. This position is a temporary stowage location that points the light beam downward, illuminating the surrounding area yet avoiding blinding dive buddies. This stowage position is useful when working with stage bottles or other equipment, as it also provides a backup way to secure the light should the primary attachment become compromised.
Feed the right-side harness belt through the canister belt loop and slide the canister to within three to four inches of the backplate. Lock the canister in place by sliding a second SS belt
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The primary light should provide enough burn time to complete the entire dive, with some reserve remaining. As a general rule, having 1.5 times the anticipated burn time is a good approximation.
The primary light cord is neatly stored in the belt when not in use, and an extra belt buckle securely holds the canister in place.
buckle onto the belt, snug to the canister and locking it in place. The additional buckle prevents accidentally dropping the canister when removing a harness. When the light is not in use, clip it to the right-chest D-ring with the “permanent” clip on the side of the Goodman handle. Stow excess light cord securely under the waistband.
Lighting technology has evolved considerably in recent years. The early history of underwater lights found divers using halogen lights, which had a filament that could easily be damaged and that also required significant power. The next generation high-intensity discharge (HID) lights greatly reduced energy consumption but still left divers with a vulnerable bulb. Modern-day lights are almost exclusively LED and provide great energy efficiency and brighter light output with superior durability. The “front-emitting” nature
of the beam can complicate a tight focus, but recent technology has reduced this problem, adding a tight focus to the other benefits of LED technology.
LED stands for light-emitting diode. It is a semiconductor device that emits light when an electric current passes through it. They are known for their energy efficiency, long lifespan, and versatility in producing different colors of light. LEDs have become increasingly popular as a replacement for traditional incandescent and fluorescent lighting due to their lower energy consumption and environmental benefits. LED lights emit light from a diode where the light is distributed forward. This is different from halogen and HID lights, which emitted light mainly from the sides of an energized filament. In the latter design, light was collected
LUMEN
Lumen (Lm) is a unit of light measurement otherwise known as luminous flux.
We use lumens to compare the total amount of light output from a light emitter. However, lumens will only tell you part of the story, because when it comes to evaluating usable light, lumens don’t provide enough information about how the light output is used. A highly specialized light-integrating sphere is used to measure lumens. A lumen is the total number of “packets of light” (or quantity of light output) produced by a light source. For example, a 100-watt incandescent lamp emits about 1,300 lumens. While useful, this does not tell us anything about the focus and/or usability of the light emitted.
LUX
Lux (Lx) is a unit of light measurement taking area into account; in other words, light intensity.
Lux is used to measure the amount of light output in a given area, where one lux is equal to one lumen per square meter. Lux is a great measurement for determining what we see as the brightness of a beam. If the light output is concentrated over a smaller area, we see this as very bright. If the light output is spread over a larger area, we see this as very weak. This is true even if we have much more light spread across the larger area. We normally use mirrors, reflectors, and optics to con trol the path of light and create the de sired beam pattern. Lux also determines the magnitude of light intensity traveling over distances. A light that is configured for high lux output will travel farther but will have a smaller footprint of light (e.g., lighthouse spotlight), and a low lux level will be configured to travel shorter distanc
es but have a larger footprint (e.g., decorative down lighting or ambient lighting).
A device called a lux meter is used to measure lux at a specific location.
The lux is a ratio of illumination (or lumens) over a distance: 1 lux = 1 lumen per square meter.
Simply put, lux is different from lumens because lux takes into account the actual area where lumens are spread, while lumens simply represent the total quantity of light produced by a light source.
From a diving standpoint, lux is a more important rating than lumens, since the higher the lux rating is, the more intense the beam is. Beam intensity is probably the most important factor for a dive light because this determines the light punch through the water and the distance that the beam can be seen. Divers should be cautious when rating different lights, especially when comparing lumens, which tend to be less useful and often over-reported by most manufacturers.
by a reflector and focused to provide a beam usable to the diver. LED lights mostly project light from the emitter in a forward direction, and some lights also collect a small amount of side-spill with a reflector. The main effect of this design is that the light is more difficult to focus with a significant amount of light projected outward. This outcome means that divers should be aware of two measures in evaluating a LED diving light: lumen and lux. See page 57.
Most diving lights now use either nickel metal hydride (NiMh) or lithium-ion (Li-ion) battery packs. While it’s true that the latter provides more energy density, it is also true that they are more volatile. Lithium batteries now come in a variety of chemistries, with some appearing to be less volatile. Solid-state batteries, which replace the liquid part of a battery pack, also promise excellent energy density and greater safety. The landscape for batteries will likely change radically in the next decade, especially given all the development for electric vehicles and other battery-powered devices in common use.
Always independently burn test your
use, burn times for rechargeable batteries will gradually lessen. It is therefore advisable to burn test your batteries at least a couple of times each season.
Backup lights are an essential piece of equipment. In the event of a primary lighting system failure, backup lights serve as a reliable source of illumination. They provide a vital layer of redundancy, significantly enhancing the safety factor during such dives.
When selecting a backup light, there are a few key factors to consider. First and foremost, opt for a backup light with simple and rugged construction. This ensures durability and reliability in challenging underwater conditions. Additionally, pay attention to the burn time of the light. It should be long enough to allow for a safe exit from the overhead environment. As a general guideline, evaluating backup lights with a burn time twice as long as anticipated is a good starting point.
Two backup lights should be carried. Each should have a bolt snap affixed with cave line. Use the bolt snap to attach one to each of the left and right chest D-rings. The body of the light should be captured under a rubber retaining band on the harness. Backup lights should be exposed so accidental ignition will be more obvious to the team. A backup light stowed inside a pocket or inside a BC can activate and discharge without the diver or team ever noticing.
The backup light is probably the most neglected piece of equipment that a diver wears. When you need to deploy a backup light, you really need it. A diver should take care to check the backup light prior to every dive and replace batteries as necessary. Even when not used, the batteries should be replaced at the start of every season and any O-rings lightly lubricated to ensure a good seal.
Advancements in battery technology have resulted in smaller battery packs, rendering corded lights unnecessary for shorter dives.
Powerful primary lights still serve a purpose, even on tropical dives with good visibility.
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Modern-day lights are almost exclusively LED and provide great energy efficiency and brighter light output with superior durability.
TEXT FROM THE GUE PUBLICATION DEEP INTO CAVE DIVING WITH CONTRIBUTIONS FROM KIRILL EGOROV, JARROD JABLONSKI, DANIEL RIORDAN, FRED DEVOS, TODD KINCAID, & CHRIS LE MAILLOT PHOTOS KIRILL EGOROV, KATY FRASER, FRED DEVOS & RICH DENMARK
The rewards and hazards of every overhead venture require that dive teams develop a comprehensive yet flexible dive plan well in advance of the first tie-off. In contrast to what the term might suggest, dive planning entails much more than just establishing the intended path of a proposed dive.
The ensuing discussion is intended to help cave divers identify certain key elements in dive planning and logistics. A grasp of these key elements will greatly enhance one’s cave diving experience with additional safety and efficiency. When preparing for cave dives in unfamiliar environments, divers should combine the information found here with personal experience, common sense, and the advice of local authorities.
The nature of cave dives demands that teams cultivate a meticulous yet flexible dive plan well before entering the water. Dive teams equipped with such plans are in a much better position to deal with unexpected challenges, prevent small problems from escalating into serious ones, and enjoy their dive experiences. Research, logistics, physical training, testing equipment, reviewing emergency procedures, and finalizing the dive plan prior to entering the water will all help prevent most problems.
Before discussing planning criteria, it is important to acknowledge that regular maintenance doubles as dive planning. For example, divers who are careless with gear maintenance could experience numerous problems on a dive trip and may be isolated from easy repairs, ultimately ruining an expensive trip and/or leading the team into a dangerous situation. Divers should also be wary of conducting maintenance on all their equipment immediately prior to a diving trip. Equipment needs to be serviced on a regular schedule, and diving recently serviced equipment on less intensive dives rather than on big dives or diving excursions is advisable. Likewise, it is important for divers to maintain a healthy lifestyle with daily fitness as a normal part of their day. It is unwise to rush to get in shape by exercising rigorously and dieting a few days before an important dive if personal fitness and a healthy diet have not been a part of one’s lifestyle. In fact, sudden changes to a person’s routine are likely to cause more problems than they solve. Therefore, an active diver is best served by creating a lifestyle that supports an ongoing health and fitness routine as well as a set of habits that supports consistency with diving skills and equipment maintenance.
The first step in organizing a particular cave diving trip is to gather information. Let’s assume a cave diving team from the United States wants to go cave diving in Mexico. What kinds of things should they consider? First, what sites will they dive? Those around Merida where
the caves are deeper, or those around Tulum where the systems are shallow and allow for long penetrations? Assuming that they decide on the cave systems around Tulum, they must then begin to gather relevant information. Which season is the best for diving these systems? What types of lodging are nearby and available? Do the divers have the correct devices for recharging batteries? Is the dive planned near a dive shop that can fill cylinders? Where can the divers rent cylinders? What kinds of transports are available? How many divers will the transports carry, and how much will it cost? Is there insurance? Can they pay by credit card? What kind of food is available? What is the water temperature? Do they need a wetsuit? A drysuit? Are heated undergarments, dry gloves, and heated glove liners needed? What kind of spare parts can they find locally? What can they rent? What must they bring? DIN adaptors for Yoke systems? Steel backplates or V-weights for twin AL80s (the local standard)? Which light and battery technologies are being used and what burn time does a given combination of a lighthead and battery provide? Is a backup primary light required based on the planned dive duration? What kind of tools are needed? Where is the nearest recompression chamber? What level of experience is required by these systems? If divers who lack the requisite experience are included on the trip, is there anything else for them to do?
Divers must answer these and many other questions before they’re ready to undertake a cave diving trip. Beyond securing suitable accommodations, ensuring that their transportation requirements have been met, and guaranteeing that all equipment, spare parts, and tool requirements are met, there are a host of minor details that can make or break a trip. Conducting the research and gathering all the necessary information before getting on the plane to Mexico, for example, can greatly help to ensure that the experience will be a truly positive one. Dive planning may vary from being a fairly simple task for a recreational dive to a complex planning and logistics exercise requiring months
of preparation in an expedition diving situation. The time required for planning will depend on the objectives of the dive and the characteristics of the exposure. Irrespective of the duration of the planning, the basic rules remain the same. All dives should have a plan (developed prior to entering the water) and be conducted according to this plan. Often this is referred to as “Plan the dive; dive the plan.”
GUE divers plan their dives considering a range of aspects to support some of the world’s most efficient diving. Planning is not just about what goes on in the water; it should also include surface strategies. All dive plans should ensure that the team clearly understands the following topics:
• Team strategies
• Points of interest and enjoyment
• Procedures
• Logistics
• Dive profiles and parameters
• Potential risks and their contingencies
• Support (both in‐water and surface)
• Nutritional requirements
At a given dive site, cave divers should always conduct a general site survey. This will hopefully verify pre-trip information. During this survey, teams should verify entry points, water conditions, diving logistics, and emergency procedures. Furthermore, cave divers should choose entrances that are convenient and that provide a reduced risk of spoiling visibility or of damaging the environment. In addition, cave divers should choose a convenient location to assemble their equipment. Equipment is usually easier to carry when assembled and transported on one’s back.
As discussed in the previous section, dive planning should be completed prior to every dive. The three key components of diver readiness are:
• Pre‐dive preparation
• Building a dive plan
• Pre‐dive sequence (including quick dive plan review GUE EDGE)
Building a dive plan is more involved than simply writing down strategies for the dive. The
It is important to have a predive plan and to follow this plan throughout the dive. This principle is commonly known as “Plan the dive; dive the plan.”
plan incorporates activities like testing the equipment, preparing food and drink, understanding logistical requirements, and identifying and managing risks. Prior to entering the water (or while resting on the surface prior to a dive), divers use the acronym GUE EDGE to review the dive plan they formulated. This acronym provides divers with a distilled version of the dive plan.
Divers should aim to perform this final dive plan review just prior to submersion. However, once again, divers will need to be flexible and decide about where and when the review should be completed based on environmental factors. The plan can be reviewed while resting at the surface, dressing for the dive, or just prior to entering the water. By the time these reviews are complete, the team should have discussed the dive plan in detail, established the order of the team and each diver’s responsibilities, and verified that everyone is comfortable with the proposed dive.
Teams should remember that all dives must take into account the diver with the least experience and should avoid plans that fixate the team on a single objective as opposed to multiple goals.
Goal-oriented diving is a reality not only in cave diving, but in most forms of diving; pretending otherwise merely prevents one from safely preparing for a dive. Even so, cave divers must avoid allowing goals from subverting common sense and from undermining sound dive parameters. They must always remain aware of their limitations and of the risks inherent in the projected dive. In cave diving, certain goals have come to characterize the nature of the dives themselves. Each one has its own method of safe execution.
The following addresses some specific logistical issues that impact safe cave dive planning. These should serve as illustrations of the critical process that works toward safe dive planning. However, specific conditions may vary from the particulars of a projected dive plan, and divers must remain cognizant of this potential disparity.
Many caves contain a flow of water that may not be predictable from day to day or even from passage to passage. For example, tidal or marine caves vary from one time of day to another. This water may flow out of the cave or flow into the cave. In the former case it would represent a spring flow; in the latter case it would represent a siphon. Divers must always remain cognizant of flow conditions and of their direction, remaining aware that moving from one tunnel to another can create a sudden shift from spring to siphon conditions. Flow conditions can significantly impact diving parameters, such as gas consumed and the time required to reach the exit, and must be carefully factored in. Divers must always remain aware that flow is a constant and potentially dangerous variable in diving.
Some cave dives require that dive teams travel along different, non-continuous, permanent lines to reach their objective. To safely perform such dives requires that teams install temporary guidelines that connect these lines. Once a dive is completed, these temporary lines are removed during a team’s exit. If marked and installed properly, these temporary lines create a continuous guideline to the main line, to the team’s primary reel, and to open water. Cave teams should carry these lines with them on spools that hold approximately 24 to 30 m/80 to 100 ft of line. When used to link the breach between the ends of two permanent lines (e.g., when crossing through a sinkhole and continuing), this line is called a gap. If the line is used to link the breach between the middle of one line and the end or the middle of another, it is called a jump.
The safe execution of a gap or a jump requires that the team leader first affix a line arrow to the permanent line the team has been following, at the site of the intended gap or jump, pointing in the direction from which they have entered. The team leader will then attach the spool line to the permanent line at the site of the line arrow placement, forge across the passage, and connect the spool line to the line in the side passage. The team should remain in visual
Studying cave maps significantly enhances the team’s comprehension of the cave layout and helps visualize the navigation challenges they may encounter.
Cave diving is an activity that requires a significant amount of gear and equipment.
“Equipment needs to be serviced on a regular schedule, and diving recently serviced equipment on less intensive dives rather than on big dives or diving excursions is advisable.
contact so they may assist one another. Jumps that cover a short distance allow the leader to connect the jump while the team waits at the attachment point. During a long jump, members of the team must stay close enough to assist one another. Typically, these distances are on the order of about 3 m/10 ft and allow for easy visual contact. On the way out of the cave, the team leader, now traveling last, will pick up the reel with assistance from the diver just ahead of them.
When executing a traverse, divers enter at one site and exit from another. In a simple traverse, one tunnel with one continuous guideline connects two access points. In a complex traverse, multiple tunnels with multiple lines are used to navigate from one access point to another.
In executing a simple traverse, divers should begin on the spring side (swimming into the flow) and treat the dive as if it were a normal cave dive. Once they hit their designated turn pressure, they should mark the line with a non-directional marker such as a “cookie” to avoid confusing other teams. They should note their gas pressure and time and exit through their original entry point. At this time, they should not remove the primary reel they attached to the permanent line. Then, on a second dive, divers should enter from the siphon side (assuming negligible flow conditions) and begin their penetration into the cave system in the direction of their marker. If the team locates their original marker before they hit their turn pressure, they can pick up their marker and continue to the other exit where their previously placed reel provides them with a continuous guideline to the open water. At that point they should remove the spring-side primary reel, and then return to the siphon side to remove their other reel.
At the end of a traverse, gas reserves should register no less than one-third of a diver’s beginning gas supply. Also, decompression obligations should be accounted for, and bottles placed at appropriate locations which, in the case of a traverse, would be at both ends (in the event that the traverse cannot be complet -
ed). Divers should also decide upon a contingency plan.
A complex traverse incorporating multiple jumps and gaps is a very advanced dive and should be undertaken only after the divers achieve a thorough familiarity with a given cave system, and only after they have amassed sufficient overall cave diving experience. Divers typically carry out at least one additional familiarization dive for each jump required during a complex traverse.
In a circuit, the entrance and the exit point are the same. However, the challenge posed by a circuit is that a segment of the dive entails oneway travel. This means that, unlike most cave dives in which divers retrace their steps, in a circuit they do not. As in the case of a traverse, both sides of the circuit should be explored and plainly marked. Divers should begin a circuit by proceeding from one side of the intended path, marking locations, and installing the requisite spools, until thirds are hit. They should then mark their location with a non-directional marker, leave whatever guidelines they have installed in place, and retrace their steps. Then, on a second dive, once they reach the other side of the circuit, they should install the appropriate guidelines and continue ahead towards their marker. If they come across their marker before their turn pressure, they can pick up their marker and complete the circuit, removing spools and markers as they proceed. Of course, the more jumps or gaps required, the more complex and challenging the circuit. Again, at the completion of a circuit, gas reserves should register no less than one-third of a diver’s beginning supply. Also, decompression obligations should be accounted for and bottles placed.
The above examples represent common cave diving objectives and are offered here to
“A complex traverse incorporating multiple jumps and gaps is a very advanced dive and should be undertaken only after the divers achieve a thorough familiarity with a given cave system, and only after they have amassed sufficient overall cave diving experience.
The use of properly marked stage cylinders and strict adherence to gas switching protocols are essential for ensuring safe cave diving practices.
provide divers with an outline of sound diving practices as well as with a deliberate approach framework. Cave diving objectives vary greatly, ranging from improving gas consumption to finishing a survey, executing a complex circuit, or exploring a new cave system. Yet, divers must identify what they hope to get out of their dives and agree that when a stated goal compromises their team’s safe return, it will be abandoned. Goal-oriented diving can increase a cave diving team’s risk if divers fixate on goals and ignore the safety parameters established at the outset. For example, divers who are intent on completing a traverse might ignore or cheat on their designated gas supply and place themselves and their team at greater risk. While diving objectives are a common, if not mandatory, part of cave diving, they must be kept in perspective and not allowed to overshadow the primary objective: a safe return to the surface.
In life, few things are as subjective and relative to personal ability and preference as what can be defined as an acceptable level of risk. For some, the risks inherent in climbing Mount Everest are acceptable. For others, acceptance of such risks reflects nothing more than a death wish. Individuals, in all facets of their life, enjoy a wide range of permissible risk. For some, very little risk is acceptable, for others, the greater the risk, the more desirable the pursuit. One of the most important aspects of planning a cave dive is properly defining risk, yet this essential component is often ignored and usually undervalued. Once a cave diving team has established its diving objectives, it must gauge the degree of inherent and artificial risk linked to the planned excursion.
Inherent risk identifies the dangers that are inseparable from the activity pursued. For instance, cave diving requires individuals to recognize that a direct ascent to the surface is not an option, and that all dive planning must account for the added risk posed by the introduction of an overhead barrier. On the other hand, artificial risks include risks that result from the behavior of cave divers themselves or are inherent risks that are not properly managed by the dive plan.
For example, the inherent risk of overhead diving can be addressed with proper training, the proper use of guidelines, team diving, responsible breathing gas limitations, proper equipment, and a sensible dive plan. Alternatively, this risk becomes amplified by improperly addressing these components. Very often, cave divers are their own worst enemies with respect to the danger of any given dive.
Few cave divers invest the requisite energy or thought into assessing the inherent risks of a given dive. On the contrary, they are often oblivious to them. Consider, for example, industry standards for labeling diving cylinders containing mixtures other than air. Divers are asked to clearly label their cylinders with markings like NITROX or TRIMIX. The assumption here is that the primary risk lies in the use of these gases. This is, in fact, untrue. In reality, the gas mixtures themselves present no risk; the risk exists almost entirely with the depth at which these are used. One nitrox mix might be used safely at 21 m/70 ft, while another might be used safely at 30 m/100 ft. However, a 21 m/70 ft nitrox mix, if used at 30 m/100 ft, would possibly result in an oxygen seizure and a fatality. In this situation, and many others like it, the misidentification of actual risk not only fails to reduce risk, but also actually amplifies it. To reduce the risk of misidentifying various breathing mixtures, divers should label the maximum operating depth of the mixture utilized.
Domains of risk assessment that commonly lead to problems include, but are not limited to, the following: solo diving, improper guideline use, violation of the rule of thirds, improper use of gas mixtures, inefficient use and placement of diving equipment, complacency around CNS oxygen toxicity, poor recognition of the value of proper experience and/or training, and sloppy management of contingency planning (ranging from separation to inadequate breathing supplies). Some of these variables even become risks as a result of divers seeking to protect themselves against irrational fears; in fact, such desires can actually create the conditions for the emergence of a legitimate threat. For
instance, divers may have an irrational fear of decompression sickness; this could lead to the misuse of high oxygen mixtures, inordinately long decompressions (which can expose divers to hostile environments), or the misuse of too many decompression mixes (creating greater oxygen risk and task loading). Improper dive planning or contingency arrangements might also leave divers stranded at sea and/or without sufficient breathing supplies.
Another key element of risk assessment is identifying individuals who share comparable levels of awareness, motivation, risk acceptance, and diving proficiency. This is because a short cave penetration can be more perilous for cave divers with limited skill than a complex cave exploration would be for divers with refined skills and experience. Cave diving, like all diving, has an element of risk. This entails that cave diving teams identify the inherent risks of a dive and strive to reduce unnecessary ones. In most cases, cave diving can be enjoyed at a very low level of risk. However, poor diver proficiency, bad planning, and the careless use of advanced technology, among other things, elevates that risk.
The risk of a particular cave dive usually has less to do with the dive itself than it has
to do with the planning, ability, and experience of the participants. In other words, cave divers generally create their own problems by not properly identifying or managing the risks of a particular dive. Learning realistic risk analysis is the single most important component of proper cave dive planning. It is impossible to craft a realistic and safe dive plan without first identifying the actual risks of the proposed activity. While gaining experience with risk identification, cave divers are encouraged to list all possible risks and to rate these in terms of the degree of threat they pose to a diver’s life.
Proper cave dive planning should either reduce or eliminate risk. Measures that do not do so should be discarded, while emergency procedures and contingency planning should properly support risk that cannot be eliminated. Generally speaking, any unresolvable problem that arises from less than three failures (equipment or action) is not a properly managed problem. For example, a scooter failure would result in a diver being towed (one problem) while two scooter failures would result in divers swimming (two problems). If the distance to the exit is too far to swim (the third and irresolvable problem), then the team did not plan properly for this dive, and they should have towed a safety scooter.
NEXT TIME: DIVE PLANNING – Part 2
Stage cylinders must be properly marked and secured to the line when left inside the cave.Area 9 Mastery Diving – Kralendijk, Bonaire
www.masterydiving.com
Base1 – Sardinia, Italy
www.baseone.it
Deep Dive Dubai – Dubai, UAE
www.deepdivedubai.com
Dive Centre Bondi – Bondi, NSW, Australia
www.divebondi.com.au
Duikcentrum de Aalscholvers – Tilburg, Netherlands
www.aalscholvers.nl
Eight Diving – Des Moines, WA, USA
www.8diving.com
Exploration Diver – Hangzhou, China
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Extreme Exposure – High Springs, FL, USA
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Islas Hormigas – Cabo de Palos, Spain
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Living Oceans – Singapore
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Plongée Nautilus – Quebec City, QC, Canada
www.plongeenautilus.com
Scuba Academie – Vinkeveen, Netherlands
www.scuba-academie.nl
Tec Diving – Luzern, Switzerland
www.tecdiving.ch
Tech Korea – Incheon, South Korea
www.divetechkorea.com
Third Dimension Diving – Tulum, Q. Roo, Mexico
www.thirddimensiondiving.com
Zen Dive Co – Los Angeles, USA
www.zendive.com
Zero Gravity – Quintana Roo, Mexico
www.zerogravity.com.mx
Buddy Dive Resort – Bonaire
www.buddydive.com
China Dive Club – Hainan Province, China
Dive Alaska – Anchorage, AK, USA
www.divealaska.net
Diveolution – Kessl-Lo, Belgium
www.diveolution.com
Emperor Divers – Sharm el Sheikh, Egypt
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Faszination-Tauchsport – Sauerlach, Germany
www.faszination-tauchsport.de
Innovative Divers – Bangkok, Thailand
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KrakenDive – Tossa de Mar, Spain
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Living Oceans Malaysia – Kuala Lumpur, Malaysia
www.livingoceans.com.my
Moby Tek Dive Center – Pahang, Malaysia
www.moby-tek.com
Paragon Dive Group – Arizona, USA
www.paragondivestore.com
Scuba Adventures – Plano, TX, USA
www.scubaadventures.com
Scuba Seekers – Dahab, Egypt
www.scubaseekers.com
Tauchservice Münster – Münster, Germany
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Tech Asia – Puerto Galera, Philippines
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