Alert Diver December 2023

Page 1


Editor DAN Southern Africa Publisher DAN Southern Africa Contributors Nicolene Olckers, Dennis Guichard, Francois Burman, Stephen Frink, Tim Blömeke, Kyle Kray, Maryka Pace, Matias Nochetto, Elizabeth Helfrich, Frauke Tillmans, Jessica B. Adams, Matthew DelTufo, Audrey Cudel, Claudio Di Manao, Gareth Lock, Gordon Yuill, Gareth Fee. Team Morné Christou, Nicolene Olckers, Dr Frans Cronje Cover Photograph By Adam Sokolski. One of my favourite photos is of the Costasiella Kuroshimae sea slug taken in Tulamben, Bali. Costasiellas are super cute, tiny creatures that resemble sheep and are one of my favourite subjects. Fondly also called Shaun the sheep nudibranch. This photo was published in the Polish edition of National Geographic, together with several other of my photos. That was one of the greatest moment in my photography life. I use the Olympus OM-1, Micro Four Thirds digital Mirrorless camera, in Nauticam housing with INON Z240 strobes. My main lens is Olympus 60 mm macro. The advantage of my setup is its relatively small size. This system provides me with good speed and good quality photos. Contact Website Advertising General Phone +27-11-266-4900 Diving Emergencies +27-82-810-6010

@dansouthernafrica @divesafety / @dan_sa_org

Alert Diver Philosophy The views expressed by contributors are not necessarily those advocated by the publisher or DAN Southern Africa. While every effort is made to ensure the accuracy of information and reports, the publisher and DAN Southern Africa do not accept any responsibility whatsoever for any errors, omissions, or any effects resulting there from. To the best of the publisher and DAN Southern Africa’s knowledge, contributors have not indulged in plagiarism. Although the utmost is done to avoid such occurrences, the publisher and DAN Southern Africa will not be held responsible for the contributors’ or writers’ indulgence in plagiarism. No part of this publication may be used or reproduced in any form without the written permission of DAN Southern Africa. E&OE.



5 9 15 18 20

Perspectives A Life Aquatic: Stan Waterman Monitoring Cardiac Health Renting Gear How To Travel Light As A Diver

95 105 108 116 124

No Sit-Ups - No Problem From The Medical Line Research Profile: Oskar Frånberg Learning From Unintended Outcomes Travel Safer

25 30 47 50 57

Dive Knives And Cutting Devices Underwater Photography: Part 1 A First-Aid Kit Fit For Diving Bary Bey-Leveld Interview Diving A Recreational CCR

126 131 138 148 157

Octopus Intelegince Revolutionising Shark Management Palau: Sustainable Superiority In Search Of Perfection Santa Claus Gets Bent

65 71 76 81 88

New Water Wings Children And Diving ESOT Calculation Team Awareness And Positioning Diving Etiquette: THe Diving Centre

162 Festive Shopping 169 Review 171 Parting Shot

DAN was established to create an emergency hotline for injured recreational divers and the medical professionals who treat them. Our funding comes from membership dues and donations to maintain the exceptional service expected by the dive community. Supported by the largest membership association of divers, our name and logo are universal symbols of safety, support, and reassurance for divers and travellers worldwide.

Diving presents the potential for a lifetime of personal enjoyment or professional fulfilment. The various options in environment, equipment, and purpose offer endless opportunities for adventure. Nonetheless, diving also involves inherent risk and a harsh underwater environment. Regardless of experience level or job title within the dive industry, no one is immune to danger while diving and accidents can happen to anyone. THE ANNUAL DIVING REPORT RELEASED BY DAN During the early stages of diving, fatalities and serious injuries were not unusual. However, in current times, they are infrequent and typically linked to unsafe actions or dangerous environments. Nevertheless, they can also happen without an apparent reason. To decrease incidents and injuries, it is crucial first to identify and then understand their causes. Knowing the reasons for accidents and fatalities results in safer diving, as the dive community can learn from past experiences. DAN's Annual Diving Report, initially released in 1988, aims to increase this understanding by highlighting the dangers of diving and advocating for safer protocols. At DAN Research, we utilise a vast network of internal and external resources to gather and assess data on dive incidents, injuries, and fatalities. We aim to disseminate this valuable information to the diving community free of charge, transforming statistics into insightful analysis that sheds light on the root causes of accidents. You can find the most recent version of our Annual Diving Report at, with plans for another edition release by the end of 2023. Central to DAN's mission is equipping divers

with the knowledge to make safe decisions on land and water. The annual reports feature case studies that offer valuable perspectives on divers' actions and underscore the significance of following proper diving protocols Please help us spread the Annual Diving Report to your dive buddies, friends, colleagues, and anyone interested in safe diving. It is crucial to promote safe practices and proactively prevent injuries to establish a culture of safety in the diving community. INCREASE YOUR DIVING FREQUENCY AND DIVE MORE FREQUENTLY Using case summaries as teaching tools is a valuable way to expose divers to different scenarios and provoke the thoughtprovoking question: What if? This allows for a thorough assessment of our preparedness and enables us to make necessary improvements. Although armchair self-study is crucial for personal growth, it should not be relied on exclusively. Regular in-water drills are a reliable method for boosting both your safety and that of your fellow divers. Consistent practice of crucial skills instils an instinctual response, enabling you to execute them correctly under any circumstances and surroundings. Increasing dive frequency fosters the development of problem-solving skills, whether encountered in open water or overhead environments. Upon thoroughly examining the DAN Annual Diving Report data, it becomes apparent that numerous injured divers chose to expand their range of dive activities without considering their training, experience, or equipment. Engaging in such daring behaviour can pose a significant danger not only to the diver but also to

those accompanying them on dives. It is crucial for individuals to always be mindful of their capabilities and limitations and act accordingly. This includes actively avoiding actions or habits that increase the risks involved, thereby preventing potentially unmanageable situations from arising. Divers must uphold appropriate levels of medical, physical, and psychological wellbeing to dive. There is a social responsibility towards other divers that relies on this. The presence of maturity and sound judgment is imperative for safe diving practices, particularly in resisting peer pressure. It falls upon the diver to ensure their readiness for any planned dives. As evident from the various incidents and victims documented in reports, accidents are unpredictable and can happen anytime and to anyone. With the help of all DAN offices, global contributors, and dedicated DAN members, we are determined to offer safety materials we hope will resonate with divers everywhere. We express our gratitude and admiration for those who prioritise their DAN membership, safety consciousness, and personal growth in light of our obstacles. Keep exploring the underwater world while prioritising safety with the support of DAN.


Even though I was a photojournalist for Skin Diver magazine for 17 years, one of the covers I most remember was not one I shot but a portrait of Stan Waterman that Geri Murphy took for the September 1982 issue. I hadn’t met Waterman at the time. Still, there he was — tanned and smiling, with a gold Rolex Submariner on his wrist, and colourfully coordinated with his orange Scubapro stabilizing jacket, red-rimmed mask, and wellworn orange 16mm movie housing with a Sekonic L-164 light meter mounted atop the optical viewfinder. The headline was “Diving’s Poet Laureate,” but to me, he was the consummate vision of an itinerant cinematographer.

A LIFE AQUATIC: STAN WATERMAN DIVE SLATE TEXT BY STEPHEN FRINK Hometown: Divided between Penobscot Bay, Maine, and Princeton, New Jersey Age: 100 Years Diving: 80 Why I’m a DAN Member: If you are a seasoned diver or want to be one, do yourself a favour and join DAN before you buy another snorkel. It will help you be educated, informed, and safe until you hang up your fins at age 90, as I did a decade ago. Even now, I keep in touch with the dive world by reading Alert Diver.


His story has been well-told over the years. Two of my favourite biographies are “A Life Overboard” from the May/June 2005 issue of the Dartmouth Alumni Magazine (where Waterman graduated in 1950) and his interview in Bret Gilliam’s 2007 book Diving Pioneers and Innovators. Both focus on a single life-altering event, one Waterman highlighted to me as well. He was enjoying the Christmas 1934 holiday with his family in Palm Beach, Florida. A souvenir was under the Christmas tree from a family friend who had just returned from Asia: a diver’s mask of the type used by the ama, women breath-hold divers who harvested Japan’s seabed. Waterman swam along the shallow reefs and jetties off the Breakers Hotel in Palm Beach, looking underwater before facemasks were readily available. “I dived down, opened my eyes, and was hooked for the rest of my life,” he said. “I was 11 years old then, but it is still so fresh in my memory that it could have been yesterday.” Waterman was born in New York City in 1923 and grew up in Montclair, New Jersey. After his parents divorced, Waterman’s childhood summers were divided between his mom’s house in Rehoboth Beach, Delaware, and his father’s summer home on a peninsula on Penobscot Bay in Maine. Maine was about tidal pools and sailing; Delaware was bodysurfing with his friends. Either way, it was about the sea, even as cold as it was. He joined the Navy during World War II and was stationed in the Panama Canal Zone, which meant the ocean was still nearby. He and his buddies loaded up their motorcycle sidecars with pole spears, masks, and fins and would dive in and spear almost anything that moved. After the war, he enrolled at Dartmouth, majoring in English and focusing on

Shakespeare. One of his instructors was Robert Frost, who may have inspired the ”poet laureate” headline so many years later. His summer romance with Susy eclipsed the significance of anything he learned in school. They married two weeks after college graduation and raised three children over their 73 years together. They initially moved into the family house in Maine to farm blueberries. That wasn’t as outlandish as it seemed — at the time blueberry farming was one of Maine’s three primary industries, alongside lobster and lumber. It was dry and dull work, but the allure of the sea was all around. U.S. Divers started around that time and sold the Aqua-Lung. Waterman bought the 25th unit in the U.S. and likely the first in Maine. He was the go-to guy for scuba diving in Maine in 1952 with his wetsuit and portable compressor. He recovered scallop drags, cleared fouled props, and even found some expensive rifles that some hunters lost when they capsized their canoes. The Aqua-Lung’s instructions said, “Don’t come up too fast,” which is still good advice. Around this time, Jacques Cousteau was having his own adventures, including making movies 150 feet underwater in the Red Sea. Cousteau’s account of these adventures, The Silent World, inspired Waterman to seek horizons beyond the blueberry farm. He wanted to travel to the Bahamas. He needed a wide-beamed and seaworthy boat, and Maine was awash in those. He took out a second mortgage on the house and bought a 40-footer he named Zingaro. With that, he headed south to Nassau, and by 1954 he had established the first liveaboard dive boat in the Bahamas. The dive business barely broke even, but it was enough to keep him on the water and shooting 16mm film with an early Fenjohn housing. He eventually amassed enough footage to edit his first film, Water World.



He went on a show circuit that typically ran from the fall through April, visiting smalltown venues and projecting his self-narrated films for $125 per show. He did 162 speaking dates in one year at his peak and eventually had three agents booking for him at a rate of $350 for a show. Between shooting in the Bahamas and being on the road, life was full for Susy at home with their children Gordy, Susy, and Gar. Maine was too isolated, and they wanted better schools for the kids, so they moved to Princeton, New Jersey, which is still their primary residence. A more urban home did not necessarily mean fewer adventures. On the contrary, the Watermans wanted family experiences while the children were still young. One of their higher-profile adventures in the early 1960s was what they call the “Tahiti year.” Stan had been to Tahiti twice on assignment and had enough contacts to plan the logistics of spending a year on location. He obtained some sponsorship from National Geographic and a commitment from PBS for an hour-long television special. I had heard Waterman suffered decompression sickness (DCS) on that expedition. I’ve had DCS a few times, but I could always reach out to Divers Alert Network, so I was interested in what happened to him in the years before DAN existed. With time, the incident didn’t resonate as a big deal to him, but Susy remembered it as being more dire. Waterman got DCS the same way as many other image-makers who wanted just one more shot. Susy said that he stayed down too long, came up too fast, and then had confusion and a loss of motor skills. He spent two days in the French recompression chamber in Papeete. Susy said it took some time for his legs to function normally, but he had no residual complications, which didn’t affect his diving afterwards.

His résumé lists several significant film projects, but for sheer audacity, nothing can eclipse Blue Water, White Death. The premise was to bring home the first underwater film of great white sharks, about which we knew very little back then. Waterman and his friend Peter Gimbel, one of the directors, discussed a concept in 1964 during Maine summer evenings by the fire. With Waterman off for his Tahiti year, it fell to Gimbel to assemble a budget and a team, which included Jim Lipscomb for topside camera and the underwater crew of Waterman and Australian filmmakers Ron and Valerie Taylor. Their first stop was South Africa because the Union Whaling Co. told them about swarms of great white sharks that attacked the whales before the crew could retrieve them to the boat. The area had plenty of sharks, but they were oceanic whitetip sharks, not Carcharodon carcharias. When no one knew much about oceanic whitetips, however, it was bold for Gimbel, Waterman, and the Taylors to leave the safety of their cages at night to get better shots of them. As for the great whites, the filmmakers got the footage they needed in South Australia with the help of the world’s most famous great white shark attack survivor, Rodney Fox. Waterman’s career was replete with other projects that kept him at the top. He became dear friends with Peter Benchley after Benchley moved to Princeton following the publication of Jaws. They had many adventures together working for the ABC show American Sportsman. That led to Waterman and Chuck Nicklin being camera operators for the Hollywood feature The Deep, with Al Giddings as the director of underwater photography. The 1977 film, an adaptation of Benchley’s novel of the same title, starred Jacqueline Bisset, Nick Nolte, and Robert Shaw, along with the largest and most ferocious green moray the world has ever known — animatronic.





Instead of dwelling on these high-profile and significant film projects while recounting his career, Waterman became most animated when speaking of the Aggressor liveaboard tours he led. Only in a later conversation with Anne Hasson of Aggressor Adventures did I understand his commitment and the time he’d invested. Between 2000 and 2013, Waterman traveled on 46 Aggressor liveaboard charters. Susy said those years were so special to him because he could go out and shoot. Being underwater with his camera and a subject fueled his passion all those years. The social aspect of being on the boat and entertaining guests with his stories and films was also meaningful. But it was all about the shooting. Waterman is now 100 years old. You don’t get to be 100 without some physical impairment. Tragically, a man who lived a life defined by his personal vision has essentially lost his sight. Yet chatting with him on the phone is both familiar and delightful. His mellifluous voice sounds the same as it has on the many stages where he presented his films to enraptured audiences, and the pure joy he exudes as he eloquently recounts a life so well-lived is uniquely Stan. September 1, 2013, is a date I can’t forget because it is in the metadata of the underwater photos I shot that day and also because it was during Waterman’s final dive trip. We were together with other guests on the Cayman Aggressor IV to celebrate Waterman’s 90th year of life and his decision to abandon his aquatic life. We were on Little Cayman’s Bloody Bay Wall, shooting from opposite sides of the same friendly Nassau grouper — Waterman with his digital video camera and me with my stills system. I paused and backed off, leaving him alone, once again communing with cooperative marine life and in the zone.

At that moment, I imagine he wasn’t feeling 90 years old. He wasn’t thinking about being on one of his last dives. He was drawing on a life of intuitive technical wizardry, knowledge of the physics of water, and instinctive composition to bring home the shot once again, as always. Note: This issue of Alert Diver went to press before Stan Waterman’s death on August 10, 2023. We join the diving community in celebrating his legacy and mourning his loss.



Imagine renting a car, navigating traffic on unfamiliar roads, and then finding yourself in a heavy rainstorm — only to realize you don’t know how to operate the windshield wipers. You would not want to replicate this situation underwater with dive gear. Whatever equipment you use to dive, you need to know how to operate it before you submerge. If you have your own gear, comfort with it comes naturally over time. When renting scuba gear, however, you may not have much time to familiarize yourself with it before diving. Fortunately, you can do some things to ensure you start the dive comfortably and confidently with the equipment you will use. When renting a dive computer, ensure you know how to read it — where to find the depth, time, no-decompression limit, remaining gas, etc. Ensure you know the meaning of the typical beeps or vibrations that will occur throughout a normal dive.

If you use a gas other than air, be sure you know how to set the breathing gas mix on the computer. Some computers hold the settings from the last dive, so even if you are on air, you will want to check this setting. If the computer is air-integrated, check that it is paired to the transmitter on your regulator. It might display information from someone else’s cylinder if it isn't paired correctly. The BCD should appear well cared for and fit you properly. Confirm that you can put it on and take it off without looking at the releases and be able to find the low-pressure inflator hose by feel. You should also be able to disconnect it from the power inflator easily. Review whether the setup is weightintegrated or uses a weight belt, and make sure that both you and your buddy know how to release your weights in an emergency. Regulators should be clean and wellmaintained. Try to take a breath out of each

second stage without connecting the regulator to a cylinder. Your mouth should create a vacuum, and you should not be able to get any air through it. After pressurizing the regulators, breathe through both before entering the water to ensure they work properly. If your spare second stage is integrated with your low-pressure inflator, ensure you and your buddy are comfortable using this configuration. When renting exposure protection, try on a few sizes to find the suit that fits you best. It should be snug but not impede movement or breathing. Alternatively, it should not be so loose as to bunch or have rolls. If you rent your mask, fins, snorkel, and boots, fit and cleanliness are your primary concerns. Try on everything, paying particular attention to mask fit. You don’t want a leaky mask to ruin your dive. It’s your responsibility to start every dive feeling comfortable and confident. With rental equipment, that means allowing extra time to learn and understand the gear you will be using. If you aren’t comfortable, ask questions until you are ready to have a fantastic underwater experience.

Dive trips are supposed to be fun and relaxing. Hauling lots of heavy equipment, on the other hand, tends to be the opposite of that – it can be expensive, timeconsuming and stressful. Dive equipment and airline travel don’t mix well. While innovations in materials and design have led to lighter and more packable gear, some products marketed as “travel versions” may not be as comfortable, durable or easy to use as standard gear. Many of us struggle with deciding which pieces of equipment to bring and which (if any) to rent at the destination before every trip. While most rental gear available at popular diving destinations is adequate, using equipment you’re familiar with feels better. Also, you'll definitely want to bring a few essential pieces of kit from home. Here are some considerations for travelling with (or without) various parts of dive equipment.

HOW TO TRAVEL LIGHT AS A DIVER DIVE SLATE TEXT BY TIM BLÖMEKE Before leaving on a dive trip, make sure your DAN membership is still active. If it isn’t, join DAN or renew your membership at Your DAN membership ensures the services of the most extensive international network for assisting divers anywhere during any emergency.

BUOYANCY CONTROL DEVICE Whether you travel with your buoyancy control device (BCD) or rent one may come down to how much you like diving with yours. While the BCD is an integral part of your kit, it can also be relatively large and bulky. You can make a case for either packing your own or renting one. Minimalist jacket-style BCDs with small bladders are available, as are harnesses with aluminium or even carbon-fibre backplates and small wings for divers who don’t need a lot of features. REGULATORS Regulators are essential life support equipment, and many divers prefer to travel with their own, for ease of breathing and for hygiene reasons. Many manufacturers offer compact and lightweight regulators for travel, sometimes using materials such as titanium and carbon fibre. If you’re diving with your own air-integrated computer, you can remove your regulator’s analogue pressure gauge to reduce weight further. An excellent way to ensure hygiene, even if you don’t own or don’t want to carry a regulator, is to bring a personal mouthpiece and ask the dive centre or resort to attach it to a rental regulator.

DIVE COMPUTER Aside from a mask, a dive computer is usually at the top of the list of things divers will carry, even when travelling light. Familiarity with your dive computer promotes both comfort and safety while diving. A wrist-worn computer that links to your regulator via a transmitter can be an enjoyable and space-saving investment, and the more compact ones can serve as your watch for the duration of the trip. MASK As your window to the underwater world, your mask is critically important. If you own one that’s comfortable, offers good visibility and doesn’t leak or fog, take it wherever you go. Be sure to protect your mask; carefully pack it, and keep it in its case when you aren’t using it. Many comfortable, lowvolume, frameless masks are available that take up less space and may be less likely to break if your luggage is dropped or crushed. And even on non-diving days, a mask is still good for snorkelling.

FINS A set of fins can range in weight from less than 1 kg to over 4 kg. Most diving in warmwater destinations can be done with a lightweight full-foot fin, with or without a neoprene sock to protect your foot. These fins are often easier to pack than their openheeled counterparts, and you won’t have to bring your wetsuit boots to use them. EXPOSURE PROTECTION Wetsuits and drysuits can be both heavy and bulky. But a thin one-piece wetsuit or trilaminate drysuit can be tightly rolled or folded and stored with your clothes; bringing your own suit ensures fit and comfort and reduces hygiene concerns. Most dive shops have exposure protection that is appropriate for the location available for rent, and it might be cheaper and easier to rent a suit than to pay fees for extra luggage. When planning to rent, it may be a good idea to bring your own skin suit to wear under a rental wetsuit. SURFACE MARKER BUOY AND SIGNAL MIRROR Although diving without a surface marker buoy (SMB) and a signal mirror is possible,

you really shouldn’t. However, few dive shops offer these tools as rental gear, so you’ll want to bring your own. If you are separated from your boat or forced to surface in an unexpected place, or if you need to get someone’s attention quickly, these items can be actual lifesavers. To be sure you can effectively use these tools if in distress, be sure to practise with them on training dives. DIVE LIGHT Shining a light during a deep or dusk dive brings to life the colours of the local flora and fauna and illuminates cracks and crevices of the reef or wreck that might have been invisible otherwise. Lights are usually quite expensive to rent relative to their price, and they’re compact and easy to carry – excellent reasons to bring one with you on your trip. Confirm airline and transportation authority policies concerning batteries before you fly.

CUTTING TOOL This is another recommendation that should really be a requirement. You don’t need to strap a big honking dagger to your leg to be a safe diver. A lightweight line-cutter or even a pair of medical shears take up very little space and usually do a much better job in most situations you are likely to encounter. SAVE-A-DIVE KIT Extra O-rings, fin and mask straps, blocking plugs for the first stage and a backup dive computer or pressure gauge are nice to have in a pinch. If your destination won’t have equipment for you to use if yours fails, consider bringing spare parts or a backup. Don’t go overboard, though – remember, we’re travelling light. CAMERA If your camera is small enough that it doesn’t need its own piece of luggage, consider wearing it around your neck or on your shoulder as a carry-on. This will keep you from having to check it at the airport and will prevent it from getting jostled or damaged. Think small while you pack, and bring just the basics. Mask, computer, torch, cutting tool, and DSMB are all exceedingly useful to have while being compact and easy to carry. Call local dive shops before you travel to check on rental-gear availability — a nearby shop might be able to provide just about everything you need. If not, get creative. Except for the exposure suit and the line cutter, you could probably fit everything on this list into a carry-on backpack if you packed it just right. And besides, how many changes of clothes do you need?

Before leaving, make sure your DAN membership is still active. If it isn't, renew your membership at Or sign up before departing on your trip. Your membership ensures you can access DAN's dive emergency services and dive accident benefits when needed.

COVER THROUGH DAN LIFESAVING BENEFITS - 24/7 EMERGENCY HOTLINE - ACCESS TO DIVE MEDICAL EXPERTS - DIVING RESOURCES TO KEEP YOU SAFE Your gateway to dive safety services & worldwide dive coverage at low annual rates!



The dive knife is an iconic part of a scuba diver’s gear. Since the inception of diving as a recreational activity, the dive knife’s presence in a diver’s equipment has influenced the public image of scuba diving as a dangerous sport and placed its participants in a league of their own. Imagine how the perception of golf or table tennis would change if its players strapped 12-inch blades to their thighs for personal safety. It was the perfect symbol for early divers — brave and adventurous thrill-seekers who lived on the razor’s edge, plunging into the depths of an unknown underwater world. For decades, divers embraced the fearless image that the dive knife helped convey. As more divers entered the water over generations and became environmentally aware of their surroundings and limitations, fantasies of underwater combat with enemy divers or predatory sharks gave way to more realistic dangers for recreational divers, such as entanglements. EXPERIENCE-DRIVEN INNOVATION Diving was not fully commercialized in its early days, lacking both speciality gear and



its distributors. The first dive knives came from what was already widely available. Kitchen knives, military surplus knives such as the leather-wrapped Ka-Bar, and wooden or cork floating boat knives were popular choices for divers to repurpose. As the industry began marketing stainless steel knives with rubber handles and sheaths for divers, the knives followed both the size trend of their military predecessors and the adventurous and dangerous image associated with them. Some knives had fierce-looking but impractical trench-knifestyle D-guards, while others had heavy hammer-style pommels on the hilt for pounding and breaking off artefacts from shipwrecks. Over time, the dive knife evolved into a safety tool, with the appearance of line cutters embedded in the length of the blade and serrated edges opposite the standard straight edge for underwater sawing applications. For practicality, blades gradually shortened in length and thickness to reduce size and weight and increase wielding ability. The addition of blunt tips to

reduce the chance of accidental injury or damage to equipment became the most recognizable element of what now distinguishes a dive knife from other knives. As dive knives trended toward safety and practical applications, cutting devices began entering the recreational diving market, having been repurposed from their original uses by the military, public safety, and technical diving communities. It is now common to see recreational divers choosing standalone mini line cutters, trauma shears, scissor knives, or folding pocket knives instead of the fixed-blade knives that reigned supreme for decades. SAFE PRACTICES As big dive knives declined in popularity, so did the common placement of knives on the outside of the thigh or calf. These placements have caused snags, caught ditched weight belts, and were hard to reach or required excessive movement to access. Today, divers place their knives and cutting devices in the buoyancy compensator pocket, waist strap, shoulder strap, inflator hose, or on their forearm. The waist belt provides equal access by both hands and lets the diver quickly confirm its presence visually. Shoulder strap and inflator hose placements also allow quick access by being near where a diver is likely to keep their hands at rest. Retention mechanisms include Velcro, pushto-release, squeeze lock, and fitted retention molds. Select a retention method that stays secure. Be comfortable with its placement on you or your gear, ensuring that you can retrieve and replace it from its stowed position without fumbling around or injuring yourself. Before diving with your selected tool, understand its capabilities and limitations by testing it before you need to rely on it.

Don’t hope it works — make sure it works. Like all scuba gear, diving knives and cutting implements need cleaning and maintenance to ensure functionality. Depending on your type of diving, you may use your cutting device only in an emergency, which is not the time to discover it has rusted shut or adhered to its sheath. However you wear it, make sure your cutting device doesn’t get in the way of your hoses or other equipment, that you can access it quickly, and that it’s reachable even if one arm is restricted, entangled, or occupied. When it comes to using cutting tools underwater, you are the biggest hazard to your own safety. Mitigate your risk by being deliberate with your actions and practising cutting skills like you would a regulator recovery or any other crucial skill. THE RIGHT TOOL FOR THE JOB Before you enter the water, consider the hazards you may encounter. The environment and your dive plan will determine if you should bring a cutting device, a dive knife, or both. Recreational divers in high-traffic areas will be primarily concerned with discarded fishing lines and equipment. In contrast, public safety divers will focus on what they can use safely in zero-visibility environments rife with potential entanglement hazards. Spearfishers may prefer a stiletto-style pointed-tip knife for quickly dispatching fish. At the same time, divers who penetrate wrecks will want heavy-duty wire cutters capable of cutting dangling metal cables or electrical wires. Big knives are souvenirs from the past for some divers, representing the wild frontier of early scuba diving. For others, large dive knives remain relevant and preferable for tasks such as probing in sand or silt, establishing a fixed position for circular search patterns, pounding stuck boat

anchors, and cutting rope from propeller shafts. There have been instances in which divers became entangled and a small cutting device was insufficient for self-rescue, such as when a diver became enveloped in a submerged wool blanket while diving in a local river. Whatever you choose to bring on your dive, both dive knives and cutting devices remain essential safety tools to have as part of your gear. You may never need to use them, but only one dangerous encounter at depth will make you wish you had one. Remember that no gear is a suitable replacement for skill development, self-awareness, and emotional self-control when facing adverse situations underwater.

In today’s world, we are spoilt for choice. But with the variety of choices comes the anxiety of choosing the ‘right fit’ for you. This is the same dilemma faced when choosing a car, scuba gear or a camera that you want to purchase. There is much to consider when buying a camera for underwater photography or video. One of the first questions you may ask yourself is: What type of camera do I want to purchase (is it primarily for stills or video)? After this, it is wise to check if you can buy an underwater housing for this specific camera. These two questions lead to question number three (or could be led by), do I have the budget? In his article, I will cover three different types of cameras and give examples of each.

s a r e m a C Action

Action cameras are normally very compact, durable and lightweight with the idea of the adventurer photographer in mind. My choice here is the GoPro. It is on its own waterproof to 10 metres (2 bars), and it makes a great accessory for snorkelling and freediving. The GoPro protective dive housing increases its depth rating to 60m (7 bars). This is a bonus for sports divers because it allows you to operate safely with it at shallower depth, well within its max. rating. The GoPro is compact, small, and light which makes it ideal for travelling. It is uncomplicated, with only two buttons, and this makes it easy to choose between photo, video, and timelapse modes while underwater. Combine this with an INON wet lens like the G140 semi-fisheye and you can close-up photographs and video accomplish amazing things. It will give you 140° wide-angle, underwater with a field of focus between 4 cm and infinity.


PROS & CONS OF ACTION CAMERAS Pros: Ideal for travel; waterproof. Cons: Smaller sensor (aka image sensor).

Chris Van Wyk


My love for the ocean started as a young boy, spending countless hours in the ocean, freediving, surfing, and exploring the shore! I remember my biggest dream was to share this world with my friends and family and hopefully inspire them to share this magical place! I started taking pictures with an old Sony 2MP (megapixel) camera in a Sony housing. I soon discovered the portability the GoPro offered and moved from the Hero 7 to the current Hero 11 model. This coupled with the INON lenses offer great macro and wide-angle options! I also own a Canon mirrorless camera in a Nauticam housing. This combination helps me to capture stunning photos and video. I share most content on Instagram @dive_capetown! This allows me to share the underwater world with lots of people, that now share my passion and love for our oceans!


GoPro 11 in GoPro Underwater Housing with Inon UFL-G140 SD Underwater Semi-Fisheye Wet Conversion Lens


s a r e m a C Compact

Compact cameras are great for beginners. Firstly, they are affordable, which makes them accessible to a lot of people. Secondly, they are also small and light which makes them ideal for travelling. Thirdly, they are fixed lens pointand-shoot cameras, which allow you to focus more on the moment than the camera settings. The Olympus TG6 is waterproof to 15m (2.5 bars) and even has a dedicated underwater mode with sub modes dedicated for snapshot (in natural light) wide, macro (for close-up), microscope (as close as 1cm from the subject) and HDR. This makes it ideal for freediving or shallow scuba diving adventures. Combined with the Olympus PT-059 underwater case, you will be able to reach a depth of 45m (5.5 bars). Alternatively, you can opt for the Nauticam NA-TG6 underwater housing, which will allow for a depth of 100m (11 bars). It is an advantage for the longevity of your housing if you can operate at a depth shallower than its maximum.


Photo taken by Shamier Magmoet with the Olympus TG-6 with Olympus TG-6 housing.

s a r e m a C Compact

Nauticam has amazing wet lenses like the WWL-C which has been especially made to match the compact camera's body, without sacrificing optical quality. The WWL-C is a powerful addition to not only Nauticam compact housings but also, via an adapter, to those from other manufacturers such as the Olympus TG-6 and their PT-059 housing. The lens is constructed with four elements and has an anti-reflective coating on both sides of the element. The front dome also has a multilayer broadband anti-reflective coating. The focal range is from the front element to infinity and has a maximum field of view underwater of 130° for 24mm equivalent lenses.


PROS & CONS OF COMPACT CAMERAS Pros: Ideal for travel; waterproof; relatively affordable; easy to use and they can produce amazing results. Cons: Smaller sensor; limited camera settings; limited zoom range.

Shamier Magmoet


When I first started diving, I wanted to bring people on dives with me. I wanted to show them what I see. When I first started using cameras underwater, I used my phone in a waterproof housing. Then I got myself a GoPro and an Olympus action camera. These were great, but they still fell short of my goal. I wanted a camera that could get closer to what my eyes were seeing when I’m underwater (without being pixelated or obscure). I wanted a stable camera, with incredible optics, and a housing that gave me full access to my camera settings. I needed a camera that could get closer to what my eyes are seeing when I’m underwater (without being pixelated and without negative obscurity.) I needed a stable camera, with incredible optics, and a housing that gave me full access to my camera settings. This is when I decided to get myself the Sony A7siii in a Nauticam dive housing. Now I can shoot in 4K hi resolution, in 25-100fsp and even in a picture profile for the more cinematic look. I love what I’m using! I appreciate being able to show others what I see, and make it look even better, without missing a beat.

Shamier Magmoet - Setting up the Nauticam housing for the Sony A7SIII


s a r e m a C Mirrorless

Mirrorless cameras are not only for the more advanced photographer but also for the beginner who is serious about getting into photography. Mirrorless cameras do not have a mirror. This allows them to be smaller and lighter. It is a digital interchangeable lens camera with an electronic (mirrorless) viewfinder. They have been taking the market by storm over the last few years. These are cameras that have simpler internal mechanics, which enables you to shoot faster than most DSLRs. Let’s look at two different mirrorless cameras at either end of the price market: The Canon R50 is ideal for beginners and provides a ‘bridge’ between a compact and the more advanced mirrorless. It has all the comfort and ease of the compact camera. It is small, easy to use and the price is similar to a compact camera. At the same time, it has all the benefits of the advanced mirrorless cameras; interchangeable lenses; and a digital viewfinder. It has amazing autofocus capabilities; excellent in low light; and has 4K video capability. Which is important to capture more detail and clarity in your video.



s a r e m a C Mirrorless

The A7SIII is a full-frame interchangeable lens camera. It has a lager camera sensor, so it does not crop your view. It is ideally for video and is a great camera for both experienced and beginner photographers & videographers. It possesses 4K; 120fps; and 10-bit video capability, with amazing autofocus and is exceptional in low light.


PROS & CONS OF MIRRORLESS CAMERAS Pros: Smaller in size, faster shooting speed, and better video capability frequently than DSLRs. Cons: A shorter battery life, limited lens selection, and higher price points.

Shamier Magmoet - Sony A7SIII with Sony 16-35mm f4 lens in a Nauticam housing with a 180mm dome port



So, choose your weapon! All the above cameras give amazing results if used in the ‘right’ way at the ‘right’ time. Decide what you want, look at what you can afford and make your move! They all have their place in the world of underwater photography.? Stay tuned for the next edition on DSLR (Digital Single-lens Reflex) & filmmaking (minimum 4K) Cinema cameras. The author, Maryka Pace, has worked at Dive Action for the last 9 years and is part of the Nauticam SA team.


Be it a jellyfish sting or a dropped tank, any injury in or on the water can be dangerous or even life-threatening without a first-aid kit. You should have one within easy reach every time you dive. And just like your dive gear, your first-aid kit needs care and maintenance to remain useful and up to date. When complete and stocked with the right components for diving-specific situations, a first-aid kit can help make annoyances vanish and incidents manageable. A basic first-aid kit for diving is comparable to a standard one you can pick up at your local pharmacy, which should contain most of the items in the checklist in the sidebar. This list is a great start. However, adding a few specific things can be very helpful for diving. While trying to stick an adhesive bandage can be entertaining, there are easier ways to cover a cut, scratch or blister. Liquid or waterproof bandages are a good addition to

divers’ first-aid kits. DAN also recommends a tincture of benzoin, which helps bandages stick firmly to the skin, especially in a damp environment. Other additions can be useful, depending on the details of your dive. Insect repellent would be one – prevention is always better than treatment. Sun protection is another, so pack some extra reef-safe sunscreen to avoid a painful burn. A flashlight is useful in dim conditions or when examining small wounds such as those caused by splinters, tiny spines or remnants of jellyfish tentacles. Also, consider if you must bring oxygen to ensure some is available. Nonlatex gloves are prone to tearing, so having a few spare pairs on hand is always a good idea. While vinegar (or acetic acid at 4-6%, like the vinegar used in cooking) is a very useful remedy for contact lesions with tropical jellyfish (e.g. Australian cubomedusae), for

some species in the Mediterranean, it can sometimes even be harmful (e.g. very contraindicated for Pelagia noctiluca, one of the most frequent jellyfish in the Mediterranean), as it may trigger the rupture of the stinging cysts (containing venom) left on the skin by the animal. The main remedy that should always be applied is the mechanical removal of tentacle residues, strictly avoiding rubbing and scratching, combined with immersion of the injured part in very hot seawater (not freshwater!) for 20 to 30 minutes to reduce pain and the local inflammatory reaction. The water should be as hot as can be tolerated (42-45 °C for most people). One of the most indispensable tools is not inherently medical at all: a writing implement. When dealing with a situation involving treatment beyond first aid, any notes you can provide about the care you have already administered will benefit medical personnel. Standard wound dressings are useful even when you aren’t diving, as cuts, scrapes, bruises, sprains and strains are among the most common boating injuries. The ability to quickly and effectively bandage a wound can minimize the risk of infection, and having the right medication or a cold pack available to deal with other minor illnesses

or injuries on board might save your dive. However, although you may try to expand your kit to cover every contingency, this isn’t possible in practice. Flexible thinking – combined with the kind knowledge and training provided in DAN courses – can help you improvise using the materials at hand when a specific remedy isn’t included in the kit. For most DAN staff, diving is not just a job, it’s a passion. A few colleagues shared their recommendations about divers’ first-aid needs from their personal experiences. TIPS FROM DAN STAFF “Make sure you replenish your kit after each use — it doesn’t take long for your supplies to dwindle.” “Always have some tongue depressors. They can be used as finger splints, cream applicators and more; the only limit is your imagination.” “Having the right equipment confidence to provide good care.”


And finally, it’s hard to say it any better than this: “Always, always, always carry a first-aid kit. List it on your scuba gear packing checklist; it’s just a matter of time before you need it.”

RECOMMENDED CONTENTS FOR FIRSTAID KITS Basic needs nitrile (hypoallergenic) gloves CPR barrier device (oronasal mask or shield) tweezers safety pins scissors antiseptic solution (isopropyl alcohol) or wipes first-aid guide Dressings and bandages Adhesive bandages Gauze pads and rolls Triangular bandages Elastic bandages Medical tape

Accessory items Vinegar Sterile saline solution Irrigation syringe Hot and cold packs Medications Aspirin Paracetamol (acetaminophen) Iuprofen (e.g., Advil®, Dolormin®, Nurofen®) Diphenhydramine (antihistamin) Hydrocortisone cream Antibiotic ointment Dimenhydrinate (sea sickness pills) Loperamide (Imodium®) Antacid (e.g., Tums®)

About The Author: Tim Blömeke teaches technical and recreational diving in Taiwan and the Philippines. He is also a freelance writer and translator, as well as a member of the editorial team of Alert Diver. For questions, comments, and inquiries, you can contact him via his blog page or on Instagram.


Barry Bey-Leveld sits in his front office and keeps a keen eye and ear on good business and excellent service. His norm is to be smiling at his desk and he enjoys working hard. His reputation matters and he offers only the highest levels of workmanship. Barry has been diving since 1985 when he was a student at Central Diving School (with Robbie Keene, another legend in diving), in Johannesburg. He loves the outdoors and he and his best mate, Dr Cleeve Roberston (plus frequently a few other avid divers) hike every week, the less frequented trails of Table Mountain, at a strong pace! However, there is nothing that Barry loves more than to have a good dive (is there ever a bad one?!) in the crispy Atlantic or in False Bay. He has thousands of dives under his belt with and without students. He is an Instructor Trainer for Trimix and CCRs and is renowned for his ability to make good things happen. His experience covers dives far and wide from Cape Town and around SA, to expeditions in Scapa Flow, Truk Lagoon, Bikini Atoll, and ice-cold diving in the waters of the Great Lakes and the Norwegian fjords (to name a few!). He likes to dive with and without a camera and both on SCUBA and CCR (Closed Circuit Rebreather). He will tell you there is a time and a place for everything!

Q | How are you involved in underwater photography? My background is electronic engineering and I have been working with underwater camera housings for the best part of thirty years. My companies, Marine Solutions (established 1999) and Dive Action (established in 1989) are situated alongside each other in our premises in Paarden Eiland, Cape Town. Barry is an owner of Dive Action and Marine Solutions. Dive Action is a 5-star dive centre close to Cape Town docks and Waterfront. Marine Solutions is a leader in underwater robotics and Remotely Operated Vehicles (ROVs), primarily working offshore. Working together with both companies in house, they can offer a high level of service, expertise and knowledge in underwater photography and video. Dive Action specialises in the servicing of camera housings and supporting underwater photographers with their equipment needs. They have been dealing with the import of the best underwater photographic equipment such as Nauticam, Subal, Zen & INON for more than fifteen years. They have also been assisting most of the top photographers and videographers in South Africa with their needs for underwater housings and accessories. The majority buy their equipment. The distinct advantages they offer are the depth of knowledge and the after sales service. Barry and his company are reliable and offer sound advice to new photographers and professionals alike. Barry has been to Nauticam (NA) Headquarters in Hong Kong and worked in their workshop and with their management team. He intimately knows how to service NA equipment and Dive Action is particularly well stocked with spares and accessories. All the housing repairs are completed in the Dive Action workshop in Cape Town. For professional underwater cameramen (and increasingly any aspiring photographer) the provision of the correct spares and this service backup are vital for minimalizing down time, saving on expense and giving peace of mind.


Q | Tips for maintenance and why an underwater photographer should service their camera housing? If a camera housing is serviced regularly (approximately every 18 months to 2 years depending upon use) it will last longer. Sometimes photographers do not rinse the housing adequately and this will allow (and encourage) corrosion. Soaking the housing in a clean tub of warm fresh water and pressing all the buttons helps to keep the buttons and levers working. You can inspect for wear and tear and if there are any signs of this or corrosion, it can be treated before it becomes critical. O rings can and will perish over time and use (even if they are not used) and a service will ensure that these are all changed. A service on a NA housing includes the change of all the O rings, circlips, and springs. This eliminates any serious wear and tear on parts, effectively stopping a breakdown on a holiday or on a film shoot.


Q | Why use a dome port and what tips can you offer for keeping it in a good condition? Take care where you choose to assemble and disassemble your equipment. It is best not to remove your camera from the housing if there is a possibility that dust or water droplets can fall into the dome port. Rather wait until you are in a clean dust free environment before working on your equipment. Never wipe the inside of a dome port. The good ones all have a special coating on the inside, and this can be damaged if touched. It is also a good idea to use a clean, lint- free, soft, micro fibre cloth when wiping the outside of the dome port, especially the acrylic domes (acrylic is softer and easier to scratch). If a dome port is damaged this will obviously affect your picture quality. Note we can replace a dome port element in Cape Town and we carry these in stock. Always use a hard dome port cover when operating from a boat. Many a dome port has been damaged due to accidental or poor handling.


Barry loves photography especially in the bush or in the water. His preferred underwater camera system is a Nikon D850 with a 24–70mm f4 lens in a NA housing combined with a WACP-1 port. He either uses 2 x 15000 lumen Keldan lights (for video) or 2 x Inon Z230 strobes (for stills). If not using this lens setup he will opt for his 230mm glass dome port and his Nikon 16-35mm f4 lens. Note the selection of an f4 lens for underwater (and not the traditional f2.8 lens). It works better underwater! His next big dive trip will probably be to the Galapagos Islands and with his camera. According to him this is what life is all about – work hard and play hard!


IS THERE A MIDDLE PATH, AND IF SO, WHAT IS IT? The Case for Recreational CCR diving. With nitrox and the cost of boat launches (and everything else) becoming more expensive, it’s starting to make sense to do rebreather diving for two and a half hours instead of doing 3 or 4 dives to get the same amount of dive time. Another factor to consider is our iffy weather conditions. The nice days on Aliwal are the best dives on the planet. I am fortunate to have dived around the world, all over the Caribbean and Fiji, done the white sharks in Guadalupe, and all those joyous things you did before your children and your disposable income was earned in dollars. I have been fortunate. I came here and still prefer to dive Aliwal shoal because you never know what will happen on the reef. You might see some tropical fish you’ve never seen before, or you will see some cold water species swim by you, a whale, a manta, or!!!!!. When the diver uses a sidemount, they take up space on the boat, and if they are doing a double outing, they will have to take four cylinders. Either that or the diver must carefully manage their gas on dive one to have enough air to do a second dive on the same cylinders. That is where the rebreather on the Shoal comes to its rightful place.




It is a perfect Nitrox blending machine, and you don’t have to worry about your mix or anything during the dive. Diving with a 36% Nitrox mix could land you in trouble if you get sidetracked by what you find and exceed the Maximum Operating Depth (MOD) or get sidetracked and forget about what you have in your cylinder. You could end up with serious oxygen toxicity problems at depth. The rebreather will automatically adjust the oxygen mix for that specific depth. You can really see it when we do the deeper reefs on the southern end of Aliwal Shoal or Landers Reef when the guys have maybe 45 minutes of bottom time when they stick at the 27 or 28-meter profile. On the rebreather, I will have 60+ minutes. The average diver will run 5 minutes into deco and must sit on a deco obligation. Twenty minutes after they are on the boat, the rebreather diver will go straight to the surface and get on the boat. “I don’t have a deco obligation because by the time I get to 17 m, my system will have adapted, and I will have 190 minutes of bottom time again.” That is the difference that is the significant safety factor for me. Doing recreational diving on a rebreather, you have so many fail safes. You have a cylinder, an O2 cylinder, a DIL cylinder, a BOV (Bail-out Valve)– a mouthpiece that can switch to open circuit mode and then a bailout cylinder with normal air. So, if you are running a no-decompression profile, it means that at any point, you can bail out from that profile, switch to 21% (Normal air), and





proceed to the surface. No deco stop is needed. If you were in deco and switched to normal air, the computer or paddle would also switch. Real life CCR dive on Aliwal Before COVID, a friend and I planned a long CCR dive at the shoal. We went out with OC divers on a double dive. The first dive was Cathedral, which was 27m deep. We stayed with the group of bubble blowers until they handed off the line and went to the surface one by one, either low on air or bottom time or both. Once the DM had left, we carried on our merry way for another 60 minutes when the OC divers came down the line and reclaimed the bouy line. We followed their profile along the Inside edge of 16-25m. They went up at the end of their dive, and we waited until the last diver was on the boat before beginning our ascent. We did a safety stop at 5m because there were some sharks around, not because we needed to and got on the boat 180 minutes after we went in the water. We had 50% of our gasses left, zero deco obligation. In terms of safety – rebreathers have a bad reputation because it is said that “rebreathers kill people”, which is not true. People kill people. In the next edition, March 2024, Part 2 -Tech vs Rec Why Not ‘rectec’?


One is not always handed a NEW piece of equipment with the invitation to try it out. My career as a working scuba instructor started in the new millennium – the year 2000. I was the proud owner of BCD, regulator, wetsuit, mask weight belt and a pair of yellow Cressi-sub Frogs fins. Over the next 20 years, my equipment would work hard. Though I worked through a few wetsuits, my ‘hard’ gear was only replaced once. Many divers, not working as instructors, would only ever buy one set of hard gear in their diving lifetime. Doing so is a personal preference/consideration. It has much to do with the fit. Some would say that colour also has an influence. Most divers prefer the very fashionable shade of Black. Parents would purchase gear for their kids, hoping to see them grow into it and scuba diving. As my BCD is old and faded, and most elasticised straps no longer have stretch capabilities, I started looking at a new Buoyancy Compensator device.


THE ‘WING’ The Cressi-Sub Aquawing came to my attention while diving in Cape Town. My first view of it was that it was very minimalistic. As it is a BCD with a metal backplate, bladder and adjustable straps, there is minimal obstruction or invasion of the diver’s frontal space and no bulky inflated bladder under your arms. The backplate is covered by cushioned back and shoulder straps in fashionable, quick-drying, netted material. The five stainless steel D-rings available can be moved and placed at the diver’s discretion. With the correct clips, one can streamline your octo and gauges and perfectly finetune your underwater profile. Then we get to the ‘wing’ or the bladder. The Aquawing has a Donut or Round style bladder, which brings both Pros and Cons.

plate, and that would most likely solve the problem. THE ‘FLIGHT’ CONTROLS The power inflator is ergonomically designed. This is a simple device, and the functions are easy enough to manage. Having dived with the same BCD for the past 20 years, it took a little getting used to how this BC is set up compared to my old one. Having to grip the power inflator to pull and dump air from your shoulder takes a little practice. I was used to having an alternative quick-dump toggle on my right shoulder. I found the quick dump valve at the back not easy to find when you are in the water ready to dive head-first underwater for a rapid descent, but again, it’s probably just because I’m used to my old BC, and my hands need to learn to find this new position. It is a personal thing as it is on the left-hand side and not the right. STOW YOUR CARGO (WEIGHTS)

The pros are that this allows air to move from one side of the bladder to the other more easily, not trapping air on one side. It can also give you a bit better lift in the area of your back where the weight belt usually sits. The Con is that when you use a shorter cylinder such as a 12-litre dumpy (like I was using), there is the chance that the bottom of this bladder can get damaged by your cylinder if you are not careful. I occasionally managed to trap the bladder under the cylinder while de-kitting after a dive, specifically when assembling/disassembling the equipment on rough surfaces where the material can get scraped or chafed. The nice thing about this ‘wing’ is that it has adjustment possibilities – there is an option to mount the bladder higher on the back

The integrated weight pocket system includes two trim pockets at the back. I found these somewhat impractical. Not the idea of weights at the back but the pockets' design. Compared to the front pockets, these are from a less durable, softer material and tend to be floppy. When tightening the cylinder strap, they need to be repositioned to do this. Diving with a 5mm two-piece wetsuit, I used 4kg weights – two in the front and two in the back. The Pockets were perfectly positioned and made for perfect trim and swimming. The front pockets get used to removing or replacing them in/underwater. The placement is a little far back, and my flexibility is not what it used to be. This BCD has been designed to give the diver a lot of freedom in the front part of the body, which is probably why the pockets are a bit farther back than I am used to.

HARNESS YOUR FLIGHT The harness adjustment is what I like the most. It takes a mere pull on the ends to tighten the harness for a comfortable, secure fit. Once it was in place, the BCD did not move around, making having good trim, buoyancy, and movement a great pleasure and easy to achieve and maintain. This adjustment system makes it great for universal fitting. I am of medium build and had no problem adjusting it to my size. Making minor adjustments, this equipment will fit anyone. I also think it will be ideal for dive centres specialising in training kids as it is compact and straightforward.

Dive Team Cape Town Simonstown, South Africa.



Cressi-Sub Equipment is also available from Into the Blue Dive Centre in Sea Point, Cape Town. GET IN TOUCH Into the Blue Dive Centre Website: DIVE TEAM CAPE TOWN Website: Instagram: @diveteam_ct



It is a good quality product. The straps and finishing are sturdy, neat and very comfortable. I liked that there were no impeding straps, buckles and bulky pockets on my front. This was especially great when finding a low position (close to the reef) to take upward pictures.

Website: Instagram:@cressiafrica

As with any new equipment, it takes time to fit into it. Things like reaching for a dump valve toggle that was not where it used to be and a shorter inflator hose kept me on my toes once I was in the water. The best practice would be to have a pool session before venturing into a rough open ocean. I am in the market for a new BCD, and the Aquawing is at the top of my list. And yes, I still have the yummy yellow Cressi-sub fins. I was prohibited from diving with them while diving with sharks. I came prepared with a pair of Cressi-sub Gara Impulse fins—more about those in the next edition. THANK YOU I want to thank Dive Team Cape Town for providing me with this Cressi Aquawing for my dive excursion.




Minors have been diving for decades, but the incidence of scuba diving injuries among them remains poorly studied. Unlike most other outdoor recreational activities, the main challenge while scuba diving is managing the inherent risks of using life-support equipment to survive a hostile environment. Scuba diving requires a specific set of skills. Demonstrating those skills in a highly controlled environment such as a swimming pool may not readily transfer to the open-water environment. Children are not small adults. Their body and organs are not just growing in size; they are also maturing in physiology and function. The prevalence of childhood asthma, for example, diminishes with age, demonstrating that the respiratory system is often still developing until teenagers become young adults. During childhood, dramatic changes in the brain allow us to perfect decision-making processes, regulate emotions, detect threats, and activate appropriate fear-related behaviours in response to threatening or dangerous stimuli. Psychological immaturity can prevent minors from reacting to underwater emergencies with the same capacity as adults. Panic can lead to uncontrolled rapid ascents, increasing the risk of pulmonary barotrauma. Children can often lose focus and make mistakes, putting them at an increased risk for a number of threats. Over the years, researchers have raised concerns about the effects of compressed gas diving on minors, especially the potentially harmful effects of decompression stress on growth rates. However, after decades of extensive diving by minors, including long-term follow-ups on cases of decompression sickness (DCS), there does not seem to be any evidence to support this theory.

The DAN Emergency Hotline is a remarkable observatory. In response to several cases involving minors who dive, DAN created a retrospective study to examine the types of injuries they experience. We analyzed records between 2014 and 2016 and identified 149 cases involving minors. As part of her 2019 DAN Research internship in the medical department, thenundergraduate Elizabeth Helfrich came to DAN headquarters, analyzed the data under the mentorship of doctors Matias Nochetto, Camilo Saraiva, and Jim Chimiak, and published the study.1 RESULTS AND DISCUSSION We split the study data into the reason for the call (initial concern) and the final diagnosis. DCS concerns were the most common reason for a call involving minors, accounting for 38 percent of the calls, followed by issues with ears and sinuses (ENT) at 26 percent. Pulmonary barotrauma (PBT) was suspected in 12 cases (8 percent), and arterial gas embolism (AGE) in six cases (4 percent). Despite its prevalence as the most common reason for the call, DCS accounted for only 6 percent of the final diagnoses. Based on manifestations, four cases were neurological DCS, four were mild DCS, and one case was inner-ear DCS. Only one minor diagnosed with DCS reported having decompression obligations during the dive. As with adults, ENT issues were minors’ most common dive injury (32 percent). Surprisingly, PBT accounted for 15 percent of the dive injuries. While no reliable data are available on the incidence of PBT in adult divers, the authors’ impression based on personal experience suggests that the number of PBT cases in minors trends much higher than in the general dive population. So, we looked at this issue in more detail.

In seven cases of PBT, there were confirmed reports of a rapid ascent; six of those involved confirmed or highly suspected anxiety. One child became anxious after practising a controlled emergency swimming ascent during training; another reported an anxiety attack that led to breath-holding and a rapid ascent. A child free diver planned a dive to 15 feet (4.6 meters) and then extended to 35 feet (10.7 meters) for unknown reasons. This child then had seizure-like activity underwater, right-leg weakness upon surfacing, and a final AGE diagnosis. It is unreported if the child breathed from compressed air at depth, although that’s likely given the symptomatology and the treating physician’s diagnosis. Three other minors likely became anxious at depth, leading to rapid uncontrolled ascents and consequent PBT. In four instances, an event that likely led to accidental breathholding and PBT happened at depth. Two of those cases resulted from equipment issues: One child reported a free-flowing regulator, while another reported being overweighted. It is likely this last diver attempted to assist ascent by increasing lung volumes with deep inspiration and breath-holding. One diver reported uncontrollable laughter underwater, another reported a “large belch,” suggesting they swallowed air at depth, and four had no identifiable reasons for injury. Also of interest is that two young divers with PBT noticed chest pain after the first dive but continued to dive for the day. It is unclear whether that might have contributed to the severity of the initial injury. The role of anxiety as an injury’s trigger and the root cause is likely underrepresented. This could be partly due to the subjective nature of anxiety and possible behavioural bias from minors not always accepting and verbalizing their fears, among other

possibilities. Anxiety and consequent panic are woven throughout many cases when considering the overall narratives. REMARKS FOR THE INDUSTRY When training individuals in vulnerable populations, no other group generates more polarization than young divers. Children often have a well-developed sense of adventure and a less-developed sense of mortality. Chronological age is a poor predictor of maturity in minors. Albeit more cryptic and admittedly rather impractical, perhaps a reflection on the intersection between biological, psychological, and social age could more accurately predict a person's response under adverse circumstances. As dive professionals must be trained and hold certifications to teach wreck diving or lead a group on a wreck, specialized training for teaching and guiding diving minors could be beneficial. This training should focus on children’s individual needs and unique behavioural aspects that make them more prone to certain incidents and injuries. Diving minors should always be at arm’s length from an able-bodied adult diver who can closely monitor them, especially regarding comfort. The distance could gradually increase as the diver matures and their stress response becomes more predictable. Safety enhancements can be made for open-water dives. Diving minors may not be reliable dive buddies due to their maturity, lower strength, and often unpredictable responses to threats. These discrepancies could compromise both divers’ safety, so a buddy system of two adults and a child would be more prudent, where one of the adults is someone who knows the youngster well and is sensitive to subtle cues of stress

or discomfort — someone such as a parent or other close relative or guardian. People who dive with children should understand and recognize the age group’s unique behavioural aspects to help prevent situations that could lead to severe injuries. With proper training and supervision, we can reasonably mitigate the inherent risks of a minor joining their family in exploring the underwater world. REFERENCE 1. Helfrich ET, Saraiva CM, Chimiak JM, Nochetto M. A review of 149 Divers Alert Network emergency call records involving diving minors. Diving Hyperb Med. 2023 Mar 31; 53(1):7-15. doi: 10.28920/dhm53.1.7-15. PMID: 36966517.


Alert Diver

Dive Safety

Pros Choose DAN Trusted When It Matters Most

Michael Clarke, Group Director, Watersport & Marine Division, Sandals and Beaches Resorts, PADI® Course Director, explains why he chooses DAN


Humans are the weirdest things... our biological systems need oxygen to survive, but oxygen is actually a dose-dependent poison: too much of it can kill us. The study of human metabolic physiology and quite how oxygen affects us in the diving and hyperbaric environment is fascinating beyond belief. One of the largest dilemmas with humans and anything to do with our biology is how we are each quite bioindividual. No two of us are quite alike. What ‘works’ for or impacts one isn’t necessarily going to ‘work’ for or impact the next. So, the best we can fairly do is consider mean-impact on the masses but remain mindful that many of us may be outliers to that mean. In terms of decompression theory or oxygen toxicity risk, that means that some of us might bend, or experience an oxygen toxicity event, whilst being well within conventional norms.

ESOT CALCULATION DEFINING PULMONARY OXYGEN TOXICITY RISK IN SUBSEA AND HYPERBARIC ACTIVITIES EDUCATION TEXT BY DENNIS GUICHARD Dennis Guichard is a multi-agency qualified Scuba Instructor Trainer & a DAN ‘Master Dive Pro’ member. He is a qualified Offshore Diver Medic, Saturation Life Support Technician, and an UHMS Hyperbaric Technologist.

Whilst conversely, some of us may be able to push the boundaries to some level of extreme without impact. Although our biology isn’t just individualistic; it’s also varied such that what we might get away with today is not the same as what might hit us tomorrow. Humans can be complicated beyond belief. The magic of math and science, however, is that we can actually calculate and predict the mean risk and probability of both Central Nervous System (CNS-OT) and Pulmonary Oxygen Toxicity (P-OT) to some degree. Although oxygen toxicity prediction is what we’d fairly call ‘stochastic’, in that it has a ‘random probability distribution that may be analysed statistically but may not be predicted precisely’. The elevated oxygen load that our bodies might have to cope with affects different biological organs at different levels of exposure. With anything between about 0.51.2 bar ppO2 exposure, our lungs seem to be one of the primary ‘organs of decay’. Between these relatively low-level limits, the Reactive Oxygen Species (ROS), generated as an excessive by-product of oxygen metabolism, predominantly damage the alveolar-capillary barrier in our lungs over time, leading to inflammation.

The production of excess ROS ceases as soon as we stop breathing the elevated ppO2 mixture or take an air break between dose exposures. The cellular alveoli damage will immediately start to recover, although the inflammation process can still continue for many hours (as much as a 5-hour delay predicted by Barbara Shykoff). Various mathematical models have been proposed over the decades to try and help predict these detrimental effects, all of which have their benefits and limitations. There’s no perfect science. As long as I can remember, our dive books have always taught us to refer to the Unit Pulmonary Toxic Dose (UPTD) methodology, also commonly referred to as the Oxygen Toxicity Unit (OTU), for calculating Pulmonary Oxygen Toxicity (P-OT) limits. The reality, however, is that those limits, developed in 1970, were never actually based on tested and validated wet dive exposures. They also didn’t make any provision for partial or complete recovery between exposures. They were an invaluable start to understanding the oxygen toxicity malady but far from perfect.

Plasma leaks into our alveoli, and our critical gas exchange interface is hindered until we literally drown in our own plasma. And it’s that time-dose dependant reduction (and limits) in pulmonary Vital Capacity (ΔVC) that we can calculate and predict.

One of the real-world challenges I’ve long battled with is trying to predict oxygen toxicity risk and probability in a hyperbaric environment where we have patients and/or injured divers breathing 100% oxygen at as much as 2.4-2.8 bar ppO2 for extended periods of time.

The pulmonary effects of diving aren’t of course just restricted to elevated ppO2 levels when other contributing factors can also cause damage to lung membranes. Such cellular damage and inflammation also lead to secondary alveolar fibrosis and further loss of diffusion capacity.

How much oxygen is too much oxygen, and how do we understand and ensure we’re not risking more harm (i.e., oxygen toxicity symptoms) than good with how we manage treatments? It should be something we can easily calculate, predict, and manage with some level of accuracy.

In the 1980s, a REPEX methodology (building on the UPTD/OTU system) was published that supposedly facilitated recovery and multi-day exposures, but it was never validated in divers. Harabin et al published a paper in 1985 with their approach to assessing P-OT, as did Vann in 1988 with another. In 2002 (updated in 2019 & 2020), Arieli et al published a fresh new methodology for calculating both P-OT and CNS-OT, called the ‘Power Equation’. So-called because of the identified time-squared non-linear regressive relationship with various forms of measurable oxygen toxicity symptoms and the known rate of hydroxyl radical production (a precursor to ROS). The Arieli methodology also includes a formula for calculating recovery between and after exposures. P-OT is typically measured in terms of the reduction in lung vital capacity (ΔVC), brought about by damage and inflammation to the alveolar membranes. The US Navy oxygen exposure limits require no more than a 2% reduction in Vital

Capacity and no more than a 10% decrement as a maximum limit. Using these limits, the Arieli methodology helps define oxygen exposure and time frameworks that we can adhere to in minimising risk. In 2015, the Shykoff ‘incidence-time model’ methodology (that I actually really like) was published, which also included a recovery model. It, however, limited consideration to a narrow exposure range of between just 1.31.4 bar ppO2 (so ideal for rebreather diver application) and is based on a different recovery approach to Arieli, giving different predictions. One of the struggles I’ve found, however, in trying to assess P-OT and CNS-OT risk when treating patients is when we have fluctuating profiles with variable ppO2, time, & air break recovery exposures. The Arieli Power Equation is simple enough for endpoint calculation with fixed ppO2 and singular overall time exposures but is immensely difficult to calculate for more complex multi-factorial exposures. Published only recently in June 2023, the

‘Equivalent Surface Oxygen Time’ (ESOT) methodology enables us to predict changes in ΔVC and recovery with ease. Based directly on a ‘simplification’ of the Arieli Power Equation, it is a fresh new approach with which I’m able to plot out literally a second-by-second analysis of predictive ΔVC impact on complex patient treatments (see accompanying graph on previous page). ESOT has tangible practical meaning in that it applies Lambertsen’s UPTD concept of expressing lung damage as ‘minutes on surface oxygen’ - 1 ESOT is thus ‘simply’ also the hyperoxic exposure reached after breathing 100% O2 for 1 minute at 1 atmosphere. I’ve calculated exposures using both the Power Equation and the ESOT methodologies, and they do align perfectly. The ESOT, however, is quite simple to plot, even for a layman like me using an elementary Excel spreadsheet. The ESOT methodology is based on a previous foundation of real dive testing in both dry and wet exposure and a clearer modern-day understanding of ROS biological activity. The ESOT approach to plotting P-OT has been adopted and formally published by the world’s leading hyperbaric and pulmonary experts on the ‘Diving Medical Advisory Committee’ (which serves the commercial and saturation diving industry worldwide), as their official ‘DMAC 35 Guidance Note’ - for more, refer to:

COVER THROUGH DAN LIFESAVING BENEFITS - 24/7 EMERGENCY HOTLINE - ACCESS TO DIVE MEDICAL EXPERTS - DIVING RESOURCES TO KEEP YOU SAFE Your gateway to dive safety services & worldwide dive coverage at low annual rates!


A team is a group of people linked to a common purpose. A group does not necessarily constitute a team. Teams usually have members with complementary skills and generate synergy through a coordinated effort, allowing each member to maximise their strengths and minimise their weaknesses. Naresh Jain (2009) proposed: "Team members need to learn how to help one another, help other team members realise their true potential, and create an environment that allows everyone to go beyond their limitations." A dive team should share common capabilities and values, providing redundancy for each other. This includes identical procedures and protocols, skillset, experience, knowledge to support the objective, similar equipment configuration, and more. A vital part of team diving is awareness of the team's physical and mental abilities and being ready to protect, support and strengthen the individuals within

the team. It is common practice that tasks are distributed amongst the team members, like primary navigation, running a reel, shooting an SMB, operating a camera, and managing the decompression strategy. All team members should be totally redundant in these tasks. Thus all team members should be able to perform any task and take over if necessary. I always refer to a solid dive team as a collective brain, interacting and seamlessly integrated, the power of a diver multiplied by the number of team members. The collective brain can perform tasks and create a level of safety and comfort beyond the reach of a single recreational diver, making team diving the perfect tool for project-oriented diving. Diving can and should typically be a team activity; for me, the team focus is foundational and a significant contributor to safety, comfort, and success during goal-oriented diving. JP Bresser, GUE Instructor


Have you ever seen a murmuration? Hundreds, sometimes thousands, of starlings fly together in a whirling, everchanging pattern, twisting and changing directions at a moment's notice. How can a swarm of birds fly as one and coordinate such complicated choreography in perfect synchronisation? It's easy to understand how one starling knows to turn when its neighbour turns since they're close together and can see each other but how hundreds or thousands of starlings manage to turn simultaneously when birds at opposite ends of the flock are separated by space and hundreds or thousands of other birds remains a mystery. Right? We are not starlings, and a 'swarm of divers' tends to be limited to a handful of individuals. But what if, beyond the beauty of the choreography, we managed to dive as one, mirroring one another or performing complementary tasks supporting one another in a perfect position? Wouldn't it be more enjoyable and safer to position ourselves and communicate anticipating the plan and

mitigating risks if an unexpected situation came to happen? Throughout our diving education, we transition from self-awareness to managing our initially unsteady house of cards basics: breathing and buoyancy control, trim and propulsion techniques. Metaphorically, and in this case, we learn how to fly with another kind of wing. As mastery builds up through practice, we follow a guide and turn our attention outwards—enjoying more of the environment and the company of others, flying metres apart in a three-dimensional underwater world. Team and awareness are two notions we have not yet envisioned. We are simply a group of individuals who dive in the same place at the same time, not having much clue about our 'buddy's' equipment, skill level, or emergency procedures management, which might differ from our own training history. Communications during the dive are a chain of reactions rather than anticipation, limited to random "OKs," or "Look at this" until someone's


pressure gauge rings the bell-It's time for everyone to head back home. Should one diver go missing on the way, we learned to search for a minute before surfacing. The whole picture is one of a poorly planned dive by a disorganised and unsafe crowd of divers. Hopefully, no one ends up kicking their neighbour's mask while turning unexpectedly to figure out 'where in the underwater world' their mate has vanished. There are two primary purposes for diving as a team: safety and complementarity. Safety is met when a reasonable number of divers (two to three maximum, four being two teams of two) join together as a safeguard to jointly address any problem such as equipment failure, intricate navigation, or environmental issues. The recommendation to have redundancy in diving applies not only to the equipment but also to the number of brains and pairs of eyes available to deal with any situation. Some dives, such as decompression dives, will require divers to mirror one another's actions as part of the procedure they have

learnt throughout the training. Complementarity occurs when divers become dependent on one another and are assigned different roles and tasks to complete a mission. Overhead environments are a good example where one diver in charge of line deployment might be the eyes forward and the other might look backward to spot any line trap, providing lightning support.

"The recommendation for redundancy in diving applies not only to the equipment but also to the number of brains and pairs of eyes available to deal with any situation.” Whatever the dive configuration, the team plans the dive, visualises the plan, dives the plan and respects the fact that any team member can call the dive at any time for any reason. More than just a golden rule, it is a safeguard.


Team Awareness and positioning are essential to members' safety and to enable communication within the team. A team member's awareness should not be distracted by poor buoyancy, trim or the inability to have a chat facing one another. This awareness is driven by the combined cognition of its members, i.e., their ability to perceive, understand, and project events based on former experiences both as an individual and as a group. The ace cards greatly support positioning: breathing and buoyancy control, trim, and efficient propulsion techniques, as we documented earlier in the House of Cards series. Navigating side by side, at arm's length, or half a body distance with one behind the other enhances the speed of response when a problem arises. Being able to locate team members visually by simply turning one's head or through passive light communication without needing to turn around constantly is a safeguard that will prevent kicking in a teammate's mask or damaging the environment.

The ability to face one another on ascents and descents, and to use the environment for the team's safety, enhances communication procedures and enables an appropriate chain of reactions should one team member suffer from vertigo or equipment failure. Using the environment for potential physical support is also part of the team awareness: for example, using a shot line rather than drifting in the blue, positioning the team to parallel to a drop-off rather than turning one's back to it, being able to deploy an SMB at depth to support the team's ascent, while also notifying the surface, earlier than later, about the team's location. Communication within the team relies on a common language that needs to be learned, practised and validated before the immersion. After several practise dives, the team learns to speak one voice. Should the team change, the voice should be no different. This is paradoxically one of the major differences between the recreational and the technical diving world: while most


recreational divers receive a briefing covering underwater communications, which typically varies from one location to another, for the most part, the technical diving community have settled on a common international language, independent of training agency. Once underwater, words are no longer spoken, but communication is enabled through other means; hand signals, writing, light signals and touch contact. However, much of the real communication is implicit, which brings us back to the foundation of awareness. Most of us have a unique buddy—the one we love to dive with because we know what each other is up to without having to express anything. This ability to see beyond the mask, read other team members, use the environment and understand the current situation, and interact does not come as a miracle—it takes time, practice and humility. Some critical skill circuits conducted as part of training sessions highlight the team's ability to cope with any challenging situation.

Most diving agencies offer a Solo diving course insisting on equipment redundancy and other safety procedures. Some divers will, of course, argue that it is sometimes safer to dive alone rather than in bad company, which is perhaps wrongly true. The differences in perceptions between divers should be addressed on the surface prior to the dive to understand what made the company 'bad' at first sight. Most of the time, the answer will relate to one of the diving foundations missing for one diver or another. Sometimes the answer will relate to poor communication, preparation and planning before anyone even dipped their fin tip in the water.

"Once underwater, words are no longer spoken, but communication is enabled through other means: hand signals, writing, light signals and touch contact. However, much of the real communication is unspoken,"

Diving is more about committing to a common goal of sharing rather than about achieving greatness on our own. Coming together is a beginning. Staying together is progress, and diving as one is a success. Anthropologists admire starlings' remarkable ability to maintain cohesion as a group in highly uncertain environments and with limited, noisy information. When uncertainty is present, interacting with a limited number of neighbours optimises the balance between group cohesiveness and individual effort. ABOUT THE AUTHOR Audrey Cudel is a cave explorer and technical diving instructor specialising in sidemount and cave diving training in Europe and Mexico. She is also renowned in the industry for her underwater photography portraying deep technical and cave divers. Her work has appeared in various magazines such as Wetnotes, Octopus, Plongeur International, Perfect Diver, Times of Malta, and SDI/TDI and DAN (Divers Alert Network) publications.


Alert Diver

Dive Safety

Pros Choose DAN Trusted When It Matters Most

Tec Clark, Associate Director, Scuba Diving Nova Southeastern University, explains why he chooses DAN.



You made it right on time: you got off the plane, looked forward to your travel bag with your dive equipment, and nearly cried in relief when you spotted it on the belt. When you arrived at the hotel, you grabbed your key but didn't head to your room: you rushed to the diving centre first, with your Advanced OWD certificate between your teeth. You finally discovered that a wreck dive was scheduled for the following day and booked your place.

"CAN I HAVE A LOOK AT YOUR LOGBOOK?" As soon as the young lady at the counter pronounced those words, an eerie silence flooded the diving centre. You felt like fainting and went from pallor to blushing in front of a 20-year-old girl. Diving centres have a thing about logbooks, especially paper format. They love logbook keepers; they love to flick through the pages, download them, tee-hee over awkward stamps. They desperately want to know where you dived last time. It's not about being nosey; it's just for your safety and that of your diving buddies. If you don't have a logbook, you could be requested to do a check-out dive. CHECK DIVES If the word logbook makes people uncomfortable, check or check-out dives trigger unnecessary anxiety, panic, and even anger, especially if you're from southern Europe. If you're from northern Europe, you'll mutter but eventually agree. Declaring that you have no intention of demonstrating anything to anybody isn't a helpful response. Either you won't be able to take part in a guided dive, nor will you get your weights and tank filled if you're planning to solo dive. Shooting your mouth forthwith something like: "You weren't even born when I learnt to clear the mask!", won't help you either.


ASKING TOO MUCH Divers generally suspect that divemasters keep the best dive sites secret for their own enjoyment. This is equivalent to believing that Netflix CEO shuts himself off, watching all the movies alone. However, Divemasters (DM) might be even more forthcoming if you ask them their favourite dive spot. However, they might suggest an easier dive if they think you are not experienced enough. The deception isn't malicious, nor do they want to make you envious when you hear others tell stories about where they've been diving. They're just doing their job: keeping you safe. Don't be surprised about the difference between European and African dive masters and those from the United States. The latter won't spare you some of their hot tea or coffee, nor will they offer to assemble your dive kit And, don't confuse Europe and Africa with the US: divemasters won't save you the tea or coffee they brought for themselves, nor are they likely to help you assemble your dive kit unless you specifically ask for help. A COUNTERINTUITIVE RULE GOVERNS SPACE IN DIVING CENTRES It's a universal rule: the horizontal surface available is inversely proportional to the size of the diving centre. Although surfaces are covered by miles of carpeting and rubber mats, they're slippery. Statistically, they're the most crowded areas, where people walk barefoot or in flip-flops. You'll soon discover that the largest diving centres and boats seem smaller than they actually are. This is because you spread all your gear everywhere.


Suppose you immediately arrange your equipment in your designated space. In that case, something amazing will happen: you'll have more room for standing and sitting. This will also improve the general mood, not to mention that it will also prevent people from tripping over your stuff. There is an upside to spreading your equipment around. You may soon find that the person next to you, formerly a complete stranger, may show great interest in a particular piece of equipment in your armamentarium. The downside of inadvertent swapping of equipment, is that you may dive a whole week with fins that are two sizes too big or small for you. You also don't want to start your dive trip on the wrong note by haggling over a contentious piece of equipment. RENTAL EQUIPMENT by definition, rental gear is used gear. If it's a centre that has just started up, be especially gracious in how you handle the equipment. If the centre has been around for a while, be suspicious of every piece of equipment, and confirm that it works optimally. This is sometimes called rental roulette, meaning you may or may not end up with trouble-free equipment. Tidiness also encourages tidiness, so if you handle equipment with care, it's more likely that others will do the same. You could selfishly feel you're allowed to do so because it doesn't belong to you. As far as possible, you should return rental equipment in the same condition you received it. Well rinsed, if possible.


RINSING TANKS The rinsing area of a diving centre is a bit like a china shop. You're bound to bump into or break something if you're not careful. Also, remember that dive centres don't frequently use disinfectants for the environment's sake. Also, don't wash your boots together with your BCDs and regulators: sand and precision technology don't go well together. IF YOU REALLY CANNOT HOLD IT This brings us to a delicate topic: Everyone knows there are two types of divers: those that say they empty their bladders in their wetsuit during a dive and those that say that they don't… Use dedicated slightly chlorinated water to wash your wetsuit, but don't use the same water to rinse your mask or regulator, please! True, relieving yourself in your wetsuit is sometimes even recommended if you're freezing. Still, no one wants in someone else's urine, so please rinse your wetsuit properly before handing it back at the end of your dive trip. If you have your own wetsuit, rinse it separately. And how about a rented wetsuit? Well, the right thing to do is wash it with a bit of soap and a wetsuit-friendly disinfectant. ADVICE FOR THE EXPERTS Divers want to have a good time, so if you can maintain a relaxed demeanour (despite your own fastidious habits or mild anxiety before diving), you will be


doing everyone a favour. There are also ways to be firm without being dictatorial, especially when it comes to getting divers to commit to check-out dives. Customer service is always appreciated, and even the most irate diver will likely calm down if you can restrain the instinctive response to treat them the same way. My personal experience is that if it has been more than six months since my last dive, a check-out dive does wonders to ensure that your first sea dive is relaxed. Offering customers well-serviced and maintained equipment is a good start towards building a reputation as a preferred dive operator. People are also far less likely to sue companies whose staff have treated them courteously and thoughtfully. With even moderate diving equipment rinsing, disease transmission is extremely unlikely. Still, it is wise to have at least two separate rinsing tanks: one for the equipment that comes in contact with the face, mouth and lungs (e.g., masks, snorkels, regulators, BCDs); and another for fins, socks and suits. Showering with a bar of neutral soap is invariably appreciated by the dive centre -- whether you had a bladder leak or not!


COVER THROUGH DAN LIFESAVING BENEFITS - 24/7 EMERGENCY HOTLINE - ACCESS TO DIVE MEDICAL EXPERTS - DIVING RESOURCES TO KEEP YOU SAFE Your gateway to dive safety services & worldwide dive coverage at low annual rates!



Core stability is vital for sports, activities of daily living, functional independence as we age and, you guessed it, scuba diving. So what do fitness gurus and your friends at the gym mean when they refer to the core? They are talking about the musculature that surrounds the stomach: the abdominals, obliques and lower back.

Out of the water, core stability is important for gear setup and transport, moving around on a rocking boat and simply standing from a seated position to embark on a journey through the deep. A strong midsection allows your body to safely and effectively oppose these external forces without suffering debilitating effects.

Core strength has a host of benefits. A stronger midsection allows you to approach the physical challenges of scuba diving and other weight-bearing activities with more force. It enables the body to better withstand the jarring external forces that are common on a rocking boat. A strong core means increased stability for balance and transitional movements such as maneuvering on land in scuba gear. Finally, and perhaps most important, a strong core reduces risk of injury. Many people work out their arms and legs, but a weak link in the center of your body increases the likelihood that an injury will take place there. A weak or inactive core is a common cause of lowerback pain.

In the underwater realm, your core takes on a whole new level of importance. The core muscles serve as the foundation upon which movement occurs. The abs stabilize the pelvis to allow us divers to propel ourselves through the water. Strong abdominals are essential to efficient finning. Weak abdominals lead to lower-back pain. Now we’ll dive into some of the best core exercises specifically for underwater adventurers. Most people, when thinking of core exercises, go right to sit-ups. But there are many ways to strengthen your core without doing a single sit-up.


EXERCISE 1 1. Start standing with your feet shoulder width apart and parallel. 2. Once your feet are positioned, stop looking at them, and stand with good posture. 3. Sit back, shifting your weight onto your heels while raising your arms. 4. Focus your eyes forward or slightly downward. 5. Raise your arms, reaching your fingers toward the sky. 6. Draw in your belly button, continuing to breathe while holding it. (This is one of the most important aspects of the movement.) 7. Begin holding for 5 seconds, and work up to 30 seconds. 8. Repeat five times.

TIPS 1. Relax your neck. 2. Keep your chest up and your eyes down. 3. Keep breathing.

CHALLENGE Try to slide your feet closer together.



EXERCISE 2 1. Begin by laying on your back with your knees bent and your fleet flat on the floor. 2. Flatten your lower back to the floor. 3. While maintaining this position, lift your hips until your body is in a straight line from your knees to your shoulder blades. 4. Begin holding for 5 seconds, and work up to 30 seconds. 5. Repeat 10 times.

TIPS Squeeze your glutes (butt muscles), and continue to breathe.

CHALLENGE Try to squeeze a pillow between your knees while you hold the bridge position (the natural tendency is for your knees to splay outward).



EXERCISE 3 1. Begin with good neutral posture and your feet shoulder width apart. (It’s a good idea to start near a wall in case you lose your balance.) 2. Transfer your weight onto your dominant foot. 3. Slowly flex your hip and knee, picking up your nondominant foot off the ground. 4. The goal is to flex your hip until your thigh is parallel to the floor, and hold your knee with your hands. Just raising your foot an inch or two from the floor, however, will activate your core. So pay attention to your body, and work where you are comfortable. 5. Hold for 5-30 seconds (depending on your balance). 6. Repeat on the opposite side. 7. Repeat five times.

TIPS 1. Keep your chest up. 2. Keep your shoulders back. 3. Focus on a specific, stationary spot. 4. Standing on a hard surface is easier. 5. If you start to lose your balance, put your foot down on the floor.

CHALLENGE Keep your knee up without using your hands.



EXERCISE 4 1. Begin with good neutral posture and your feet shoulder width apart. 2. Fold forward at your waist, allowing your arms to dangle toward your toes, and relax. 3. Bend your knees slightly, and extend through your back so that your hands hang at knee level. 4. Squeeze together your shoulder blades, and contract your belly button toward your spine. Your back should be flat like a table top. Your head and neck should be in a neutral position, with your eyes focused slightly in front of you. 5. Hold for 5-10 seconds while continuing to breathe. 6. Release back into a forward fold. 7. Repeat 10 times.

TIPS Focus on squeezing your shoulder blades and preventing your tummy from sagging.

CHALLENGE ncrease the duration of the hold to 30 seconds. If you follow the exercises listed above, you will be on your way to a rocksolid core — without doing a single sit-up. Enjoy your newfound strength, and continue on your journey through the water uninterrupted by injury. NOTE: To avoid an increased risk of decompression sickness, DAN recommends that divers avoid strenuous exercise for 24 hours after making a dive. During your annual physical exam or following any changes in your health status, consult your physician to ensure you have medical clearance to dive.


COVER THROUGH DAN LIFESAVING BENEFITS - 24/7 EMERGENCY HOTLINE - ACCESS TO DIVE MEDICAL EXPERTS - DIVING RESOURCES TO KEEP YOU SAFE Your gateway to dive safety services & worldwide dive coverage at low annual rates!



Q | I have been diagnosed with low platelets. Is it OK to dive? Before you dive, you and your doctor should consider some possible effects of having a low platelet count. In some cases, it may affect the body’s ability to clot properly in response to injury. Cuts and bruises are common injuries in almost any recreational outdoor activity, so you should take extra care to avoid cuts and scrapes. Middle-ear and sinus barotraumas are the most common dive injuries. They are typically self-limited because normal coagulation stops the internal bleeding, giving divers time to seek professional medical treatment. When a diver has issues with clotting, pressure on the wound will control bleeding. Since applying local pressure is impossible with internal bleeding, ordinary ear, nose, and throat barotraumas can become medical emergencies.

Decompression injuries add another dimension to bleeding risk, as bubble formation and growth cause microscopic tissue damage through mechanical tissue disruption and normal inflammatory processes. Coagulation can control these microbleeds, and recompression therapy can revert bubble growth, wash out inert gas, and minimize inflammation. However, when a diver has clotting issues, the micro bleeding caused by bubbles can reduce the effectiveness of recompression therapy. This problem can be critical in severe cases, such as spinal cord involvement or an arterial gas embolism. Ben Strelnick, NREMT, W-EMT Q | Six weeks ago, I had a portion of my left lung’s lower lobe removed due to a nodule from stage 4 melanoma, and I am now starting immunotherapy. The surgeon and pulmonologist say it is safe to resume diving. Is there any specific information that suggests otherwise?

Diving is not recommended during any ongoing cancer treatment due to the unpredictability of the drugs used. You will likely be in poorer health and weaker than usual during treatment. Additionally, six weeks is insufficient for thorough healing after an invasive procedure. Complete recovery and a physician’s clearance for full and unrestricted physical activity are necessary before diving. Generally, diving is not recommended after any surgery that removes a section of lung tissue. Changes in the lung’s structure can predispose you to a fatal pneumothorax. Since barotrauma can occur with lung tissue hyperinflation, the diver’s lungs must be able to tolerate rapid changes in volume and pressure. Fibrotic or scarred tissue has reduced compliance, and any lung structure weakness may rupture from slight overinflation. Pneumothorax can be dangerous enough on its own, but the result may be fatal when it happens underwater. It can develop into a tension pneumothorax on ascent: The affected lung collapses, and the increased pressure underwater stresses the heart, vascular structures, and healthy lungs along with the heart and vascular structures. We recommend that your care providers contact us directly for a consultation. Ben Strelnick, NREMT, W-EMT This page is dedicated to the memory of Ben Strelnick (1984–2023), our DAN colleague and friend, who passed away in May from a cave diving incident.


Alert Diver

Dive Safety

Pros Choose DAN Trusted When It Matters Most

Ivana Inglesina & Victoria Cole, PADI® Platinum Course Directors, Pro Dive Vibes, Curacao, explain why they choose DAN.


Oskar Frånberg leads the research group in marine systems engineering at the Blekinge Institute of Technology in Karlskrona, Sweden, and is managing director of the Swedish National Underwater Technology Center. This father of three is an engineer by training and has been active in dive research, especially rebreather physiology, for over 20 years.

mechanical rebreathers. I tested several rebreathers and made mathematical models of their oxygen content. To verify the models, I developed a metabolic simulator to test and measure the rebreathers' oxygen and carbon dioxide content. It could also simulate ventilation-perfusion problems in the lungs. This simulator has been proven useful in testing medical regulator ventilators and anaesthesia machines.

HOW DID YOU GET INVOLVED WITH DIVE PHYSIOLOGY? I’ve always been fond of the sea and enjoyed swimming and snorkelling as a kid. My first real dives were in 1996, when I became an explosive ordnance disposal (EOD) diver during my service in the Swedish Navy, and I have kept diving ever since. One of my most noteworthy dives was during the excavation of the 17th-century Swedish warship Kronan, where we found and salvaged a chest with 6,500 silver coins dating back to 1675.

WHO ARE YOU WORKING FOR RIGHT NOW? In 2015, the vice chancellor at the Blekinge Institute of Technology invited me to help develop a five-year marine engineering program, so I moved to Karlskrona and took a hiatus from dive research. We started the first class after two years, and I remained the engineering program manager for the first three years.

After my military service, I studied engineering at the Chalmers University of Technology in Gothenburg. I developed and patented a new type of rebreather that extracts oxygen from the air and releases it with heat during the dive. This led to a collaboration with the Navy that later funded research on rechargeable carbon dioxide scrubber technologies.

It is not a classical naval architecture program — it’s more focused on marine systems engineering and marine robotics. This broader focus makes the program tougher than usual. Of the first 20 enrollees, 30 percent graduated after five years, but employers recruited all of them directly from the program. We now enrol about 30 students per year, of which about 40 percent are women, which is quite extraordinary for an engineering program.

I worked for a few years in Stockholm at the Military Diving Center (MDC) — an interesting work environment with a mix of engineers, physicians, and operative divers — before starting my PhD in biomedical engineering at the KTH Royal Institute of Technology in a joint group with the Karolinska Institute (KI). This versatile environmental physiology group encompassed the major fields, including aerospace, sports, thermal, and dive physiology.

Did you miss doing diving research during that time? Yes, absolutely. Diving is what got me into research. However, I was not completely disconnected since I still supervised Ph.D. students. I like the mix I get with the more technology-driven development of remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), and submarines.

TELL US ABOUT YOUR DISSERTATION. My PhD was about oxygen content in







Navy decompression tables since the 1950s. Despite a big effort to rewrite them in 1988, the resulting SVEN 88 tables saw limited practical use, so Sweden kept using the U.S. Navy tables. In 2010, the Swedish Navy switched to using the tables from the U.S. Navy Diving Manual, Revision 6. At the same time, our EOD divers switched diving units, and we started seeing quite a lot of decompression sickness (DCS) in the Navy from 2012 onward. During our investigation, we saw multiple contributing factors, including the switch to composite cylinders for a lower magnetic signature for the EOD divers. It turned out that those cylinders leaked gas, and we didn’t realize that they were selectively leaking oxygen. As a result, we now have very strict rules for gas analysis. We also saw a few profiles in the U.S. Navy Diving Manual, Revision 6, that generated more DCS. At first, we thought these decompression sequences were a technological issue since we had just switched units, and it took a long time for us to figure out the problem. When the U.S. Navy released Revision 7 of their dive manual, we had to choose whether to follow this revision or develop something ourselves. The navy staff decided to develop its own solution to leverage the benefits of a proprietary algorithm that could be customized for any dive profile and system and digitized for a dive planning program or computer. Thus, I received a grant from the Swedish Navy to create a working group to develop a new table, SVEN21. I hired an engineering PhD student, a postdoc mathematician, and two medical doctors to integrate decompression physiology. It took a lot of investigative research to figure out how to develop decompression algorithms, and we learned a lot about decompression models and the decompression tables used in other

countries, such as France, Canada, and the Netherlands. We ended up with validations of a model that is closest to that of Edward Thalmann — one that calculates exponential gas uptake and more linear off-gassing. Our recommendation to the Swedish Navy was that this was the most validated model available and not far from U.S. Navy Revision 7. HOW DID YOU VALIDATE THE DECOMPRESSION TABLES? The Swedish Navy staff wanted a table with only a 1 percent risk of all-over DCS and 0.1 percent risk of central nervous system DCS instead of the 2.3 percent risk of the U.S. Navy Revision 7 tables. We got close to that level in our model and then had to develop the testing process. The Swedish navy had closed the MDC and built the Diving and Naval Medicine Center (DNC), a new dive research facility in Karlskrona in southern Sweden. It allows for human diving to a depth of 525 feet (160 meters) in a waterpot chamber and unmanned breathing apparatus testing to a depth of 656 feet (200 meters). It also has a swim flume, indoor and outdoor pools, a dive school, and a technical development section and associated researchers. This was the perfect location for our validation dives. We did 163 dives on different profiles and studied symptoms and bubble scores, cardiac 2D ultrasound, and audio Doppler. We successfully validated the tables, which will be implemented later this year. WHERE DO YOU SEE DIVE RESEARCH GOING IN THE NEXT 10 YEARS? We haven’t really started addressing ergonomics in diving — not just breathing ergonomics, but also the man–machine interface. I think that will be the challenge for the next decade or so.

YOU WERE AT REBREATHER FORUM 4, WHERE WE TALKED ABOUT ACCIDENTS AND FATALITIES AND HOW THEY ARE STILL HAPPENING AT A DISTURBING RATE. WHAT IS YOUR TAKE ON THAT? I think rebreathers are becoming more mainstream, and I see the risk is that rebreather divers now are less trained and less educated. They progress in their training too quickly, too far, and too soon. Rebreather diving is complex, with advanced interaction of both medicine and technology. I see even specialized engineers who are supposed to understand fundamental concepts such as compression and thermodynamics. But it even takes them a long time to grasp the fundamental concepts, such as constant partial pressure of oxygen (pO2) versus constant oxygen fraction or oxygen metabolism. The average diver will likely have more difficulty understanding those complex concepts.



The three gases generally used in recreational and technical diving are oxygen, nitrogen, and helium. Nitrogen is the most abundant and is usually the default gas, but no one seems concerned about its purity, although the U.S. Compressed Gas Association (CGA) provides purity levels, or grades, for various applications. Helium is the most expensive. It makes up less than 0.001 percent of our planet’s atmosphere, or 50 parts per million (ppm), and it liquefies at an extreme temperature of –452°F (–269°C). Helium is the second most abundant gas in the universe, and our sun produces hundreds of tons of it each second. Since we can’t harvest solar helium, we rely on radioactive decay to produce what we need. Fortunately, the form we extract is entirely stable. When considering the purity of helium that divers should consider when making their gas blends, the commodity specification for helium (CGA G-9.1) conveniently uses

“diving/respiratory applications.” The specification covers a range of what we refer to as grades, or quality verification levels, which define the required purity and allowable contaminant levels. Each batch of helium is analyzed to determine if it meets the minimum levels for a particular grade. Balloon grade H is the least pure at 97.5 percent. That is quite pure for breathing purposes, but the trouble is that the standards for that grade do not catch all potential contaminants. It could contain 0.025 percent (250 ppm) carbon monoxide (CO), and you would not know it until you ascend from 60 feet and start to feel terrible. Next is medical grade J, which meets a 99.0 percent minimum specification and is certified to have CO less than 0.001 percent (10 ppm). This grade is also safe for a breathing-gas mix, but only at the surface. Like oxygen, this is considered a drug and requires a medical prescription for purchase.

We can skip grade L, referred to as welding gas. Grade N helium has a purity level of 99.997 percent, which means potential contaminants of only 30 ppm, and it is the grade that the CGA considers suitable for diving and respirator applications. It’s important to remember that all these gases, used for everything from balloon to diving applications, are produced as pure helium. The only difference is what the analysis looks for during the verification process. We do not want excessive amounts of contaminants that will affect human physiology at depth, so we need to purchase diving-grade helium. Even medical grade helium has a remaining 1 percent, which is 10,000 ppm, that could contain something we don’t want to breathe at pressure. Using helium with a total impurity level of 30 ppm ensures that we are breathing a safe gas mix.


COVER THROUGH DAN LIFESAVING BENEFITS - 24/7 EMERGENCY HOTLINE - ACCESS TO DIVE MEDICAL EXPERTS - DIVING RESOURCES TO KEEP YOU SAFE Your gateway to dive safety services & worldwide dive coverage at low annual rates!



In the aftermath of diving incidents, the diving community often finds itself ensnared in a whirlpool of blame, diverting attention from the pressing need to learn from these tragic events. A reflective blog by The Human Diver provides poignant commentary on this issue, centred around the unfortunate demise of a diver. While the standard response is to wait for official investigations, these are frequently focused on identifying culpability rather than facilitating understanding and growth. The "Learning Review Guide in Diving" from The Human Diver disrupts this status quo, encouraging a shift towards a sense-making, not blame-focused, evaluation of events. EMPHASISING HUMAN FACTORS IN DIVING For years, The Human Diver has been at the forefront of integrating human factors into diving safety, drawing on lessons from high-risk domains like aviation and healthcare. Despite some scepticism, the criticality of these factors in diving is unequivocal. Industry challenges for learning from incidents include a lack of a cohesive incident reporting mechanism and a myriad of definitions for what constitutes an incident, muddying the waters for clear learning outcomes. Drawing inspiration from Dr Ivan Pupulidy's innovative approaches within the US Forest Service, the guide seeks to decode the motivations and decisions of divers and supervisors/instructors within the complexity of diving activities. The Guide The guide addresses a spectrum of diving professionals—from commercial and military divers to those in media and academia—acknowledging the diverse organisational context in which they operate. The goal of the guide is to move ‘up and out’ and not ‘down and in’, where it is easy to blame. While designed for the diving industry, the guide's foundational principles have relevance across a range of complex operational systems. "The Learning Review Guide" is split into two parts: essential concepts for organising reviews and a toolkit with additional resources and references to build divers and practitioners knowledge. “The Human Diver” also offers more in-depth courses to cater to those who prefer a hands-on learning experience. SIMPLE. COMPLICATED. COMPLEX. THE DIFFERENCES ARE IMPORTANT WHEN IT COMES TO LEARNING. Classified by safety science, systems range from simple to complicated and complex. Diving incidents predominantly occur within complex systems, where a mesh of interrelated elements complicates tracing cause and effect. Acknowledging the complexity of the system in which an incident occurs is crucial for suitable and efficacious prevention strategies. Recent insights from The Human Diver advocate for a move beyond singular learning loops to embrace double- and triple-loop learning, fostering systemic change and shifting the focus away from individual blame. Learning Reviews represent a paradigm shift from conventional investigations by prioritising understanding and learning rather than just focusing on compliance or non-compliance. Recognising that errors occur across all levels,


Learning Reviews advocate for an all-encompassing perspective, probing the contextual and systemic factors that influence decisions. This approach equips diving teams to establish stronger safety systems, enhancing the capacity to learn from the entire context surrounding an incident, not just the specific behaviours of those directly involved. THE MECHANICS OF CONDUCTING A LEARNING REVIEW Commencing with detailed information collection by gathering and exploring narratives from multiple stakeholders to construct a comprehensive account, Learning Reviews utilise a Network Influence Map as a tool to represent the interaction and interdependence of influential factors, aiding in identifying themes and conveying the complexity of events. Subsequently, expert analysis seeks to highlight where similar risks may reside within the wider diving system and explores potential mitigation strategies. This phase of analysis moves away from the particulars of an incident, widening the lens to consider 'normal' diving operations. A key element of the guide is the emphasis on comprehending the "local rationality" of individuals—how their decisions made sense given their circumstances, objectives, and available resources. The conclusion of a Learning Review process is the generation of bespoke Learning Products, designed to address the specific needs of various


stakeholders within the diving ecosystem, ranging from field divers to instructors and organisational leaders. Generic reports are deemed insufficient; nuanced and actionable learning is the objective to ensure meaningful dissemination of knowledge. SUMMARY The captivating call of the undersea world is not without its inherent dangers. Although safety may not always be the foremost priority due to finite resources (despite what some might say), safety is undeniably a significant aspect of diving operations. The Human Diver's guide serves as a proactive tool for reflection and learning from past incidents, presenting a systematic and constructive framework. Placing a systems-oriented thought process at its core and contending with the multifaceted nature of diving incidents, the guide heralds a new era of learning from unintended outcomes and events. This innovative methodology enables divers and their organisations to assimilate historical lessons and chart a course toward a more secure and informed future under the surface. The 24-page Learning Review Guide for Diving can be downloaded for free from here


Amid the bustling season of year-end getaways, the anticipation of an overseas holiday sparks meticulous planning for travel arrangements. Amidst the excitement, it is crucial to deliberate on medical emergency coverage, particularly for scuba divers venturing into the depths of international waters. Understanding the inherent risks of occupational and recreational activities while travelling is paramount. Securing primary medical coverage involves proactive measures, such as notifying your medical aid company about your travel plans, obtaining additional travel insurance, or both. Many Medical Schemes include international travel benefits in their plans through global partnerships. To ensure continuous coverage while abroad, informing the scheme and requesting a travel certificate is imperative. Most medical aids extend coverage for up to 90 days outside your country of residence, safeguarding you during international adventures.

However, the scope of medical aid coverage may be limited. Additional travel insurance becomes necessary for non-medical emergencies, extended coverage beyond 90 days, and comprehensive protection beyond medical emergencies. Here's why: Non-Medical Emergencies: Travel insurance comprehensively covers nonmedical emergencies, such as trip cancellations, lost baggage, and travel delays—areas your medical aid may not address. Extended Coverage: Medical aid coverage during international travel is typically confined to 90 days. For prolonged trips, additional travel insurance becomes indispensable for sustained protection. Comprehensive Protection: Travel insurance offers an expansive spectrum of coverage, encompassing personal liability, legal expenses, and more. It establishes a comprehensive safety net that extends beyond mere medical emergencies.

For those without medical aid, prioritising financial health is imperative. Comprehensive travel insurance acts as a financial safeguard, covering medical costs and allowing individuals to focus on recovery without the burden of financial concerns. In circumstances necessitating evacuation to a facility with superior medical capabilities, travel insurance frequently includes coverage for emergency evacuation, ensuring timely transportation to a medical facility equipped to address specific needs. While medical aid and travel insurance may offer coverage for occupational and recreational activities, the extent varies based on specific policies. Individuals engaged in high-risk activities should meticulously review their insurance plans, contemplating additional coverage for a comprehensive protection umbrella. Specifically tailored for scuba divers, being a DAN member ensures coverage for dive-specific injuries, including hyperbaric chamber treatments and evacuation expenses. This becomes crucial in remote diving locations where specialised facilities may be limited. Whether through primary medical cover or comprehensive travel insurance, having adequate protection ensures that the joys of travel, especially for scuba divers exploring the underwater world, can occur with confidence and peace of mind.


Octopuses are strange and fascinating creatures, so strange that some people truly believe them to be aliens with cosmic origins. But these shape-shifting, color-changing creatures with eight arms and three hearts are just another one of Mother Nature’s works of art. Although mind-boggling, their abstract design is not what interests me most about these creatures; it is their intelligence, unique personalities, and complex behaviours. When discussing animal intelligence, one tends to associate brain power with other primates, cetaceans, or your household furry friend. You’d assume that a mollusc, a relative of your garden snail, has no business being so smart. But octopuses are rule-breakers who don’t like being told what they can and can’t be. These animals have baffled scientists times, and on the topic of intelligence, they’ve made experts rethink leading theories on its development and evolution.


The Social Intelligence hypothesis suggests that higher intelligence evolved to navigate social group dynamics. This hypothesis holds true for dolphins, chimps, and humans, but for the octopus, the most intelligent and innovative invertebrate, they are the exception. From the moment an octopus is born, the baby must fend for itself and quickly learn to recognise its food and foe, how to hunt, and avoid being hunted. Lacking a protective shell or any defensive weapons, an octopus is extremely vulnerable to predation. But their secret weapon is their brillant mind. They can outsmart their predators, avoiding detection by blending into their environment, evading pursuit by using tools or an inky ‘smokescreen’, or even escaping their predator's grasp once captured. There are reports of Octopuses blocking the gills of sharks, practically suffocating them until they release them from their grip. Octopuses have even, on occasion, outsmarted humans. In her book “The Soul of an Octopus”, Sy Montgomery recalls a story from New England Aquarium where researchers reported that their fish were mysteriously disappearing one by one... There were no predators in that exhibit, so the aquarists could not figure out where they were disappearing to. One day the culprit was caught red-handed. An octopus from a nearby tank would break out and walk across the floor for some late-night fish fingers, then return to its tank and close the lid to cover his tracks. Captive octopuses are known to be escape artists, and many aquariums have enrichment programs, giving the octopus toys or puzzles to keep them mentally stimulated and out of mischief. In the wild, there is plenty to keep them busy. Octopuses are extremely adaptive predators with a big appetite. Each type of prey requires a different strategy.

One of their favourite meals, a juicy crab, is fast and armed with sharp pincers. The best way to capture a crab is a surprise attack requiring stealth and camouflage or a hypnotic display to mesmerise and confuse the unsuspecting victim. Most fish are too quick to pursue, and so some octopuses have learned to hide and use the tip of one of their arms to mimic a worm, drawing the fish into a trap. Other mollusks like abalone or limpets are easy to catch but are protected by a thick shell and are suction cupped to the substrate. An octopus will drill through the shell and inject venom to weaken the muscle before they can be removed and eaten. Most impressively, the octopus knows the exact spot on each prey where the venom will be most effective, and that requires the least energy to drill. Octopuses are also master trackers. They know exactly where to find their favourite prey and create mental maps of their habitat, always aware of the quickest route home to safety. All of this knowledge, adapting, and problem-solving is a lot for an octopus to learn and remember in its short one-to-two-year lifespan. This contradicts all the assumptions of the social intelligence hypothesis and requires a new theory – the ecological intelligence hypothesis. This theory explains that octopuses have evolved their impressive intelligence to navigate their complex ecology and survive successfully. As a diver, it is always exciting to see an octopus and a privilege to witness them in action. Whether it be on a hunt or avoiding the four-limbed, bubble-blowing potential predator by blending into their environment, octopuses are always a highlight on a dive. They are also very curious and look back at you with the same wonder and amazement that you look at them, sometimes even extending an arm to get a feel and taste of you. Octopuses are capable of recognising individual humans.



Captive octopuses are known to squirt water jets at people they don’t like and enjoy holding the hands of their friends. A special case of this was witnessed in the Oscar award-winning documentary “My Octopus Teacher”, where a man formed an intimate bond and friendship with a wild octopus. It is important to remember that with this higher intelligence comes sentience. Octopuses are capable of experiencing pleasure and pain, stress, and excitement. They also have individual personalities, meaning some will be more curious of you while others will be terrified. Not every diver will experience a ‘My Octopus Teacher’ moment, and it is important not to try to force one. Be respectful of these animals, observe them from a short distance, and do not stick your hands into their den or try to touch them. If they reach out for a high five or to check your camera settings, be gentle, let them lead the interaction, and hope your dive buddy has their camera ready.


DELIVER OXYGEN FASTER WHEN EVERY SECOND COUNTS Respond to a dive incident faster with DAN emergency response gear.




The eco-friendly SharkSafe BarrierTM technology, developed by marine biologists at Stellenbosch University (SU) and their collaborators and manufactured in the Western Cape, South Africa, has now been installed on a private island in the Bahamas. The SharkSafe Barrier combines biomimicry of a kelp forest and magnetic fields to keep humans and sharks apart from each other without harming the sharks or large marine species. According to Dr Sara Andreotti, a marine biologist at SU and co-founder of SharkSafe BarrierTM, this nature-inspired technology is currently the only eco-friendly alternative to shark nets, which result in the death of thousands of sharks and other marine life every year. The installation of a 30-metre long SharkSafe Barrier at the Berry Islands in August this year will further strengthen marine conservation efforts in the Bahamas. In 2011, the Bahamas proclaimed the first shark sanctuary in the Atlantic Ocean and, in 2018, a Marine Action Partnership (MAP) for Sustainable Fisheries. Shark tourism currently contributes approximately US$100 million annually to the local economy. MORE ABOUT THE TECHNOLOGY Dr Andreotti says since 2012, the technology has undergone rigorous testing in the turbulent ocean waters along the South African coast and the tropical waters of Réunion island and the Bahamas. The results from several of these case studies have been published in peer-reviewed scientific journals. Firstly, fish and other marine animals, such as seals, have been observed to use kelp forests as a hiding place from predatory sharks. By bio-mimicking a natural kelp forest created by overlapping rows of plastic pipes anchored to the seabed, the SharkSafe

Barrier has proven to be an effective deterrent for predatory sharks. Secondly, marine biologists know that most shark species are sensitive to strong permanent magnetic fields because of the presence of electromagnetic receptors at the tip of their heads. These small gel-filled pores – called ‘Ampullae of Lorenzini’ – are connected directly to sharks’ brains, allowing them to register faint bioelectrical impulses dispersed in the water from their prey. Using this knowledge, the developers of the SharkSafe BarrierTM created a strong magnetic field by inserting magnets into the kelp-like pipes. But instead of attracting a shark's attention, the overly strong magnetic field over-stimulates the Ampullae of Lorenzini and, therefore, acts as another repellent. In other words, inserting strong magnets into the barrier's kelp-like pipes further strengthens the design's ability to repel sharks, Andreotti explains. Today, the SharkSafe BarrierTM consists of high-density polyethylene pipes manufactured locally by KND Fabrications in Maitland, Cape Town. During installation in the ocean, the buoyant pipes are anchored on a grid-like structure one metre apart from one another, with large ceramic magnets staggered in the ocean-facing row. The grid is then weighted by limpet-shaped 200-kilogram cement blocks and secured by rock anchors and sand. Apart from the SharkSafe BarrierrTM combining two proven shark-repellent strategies, it has also been designed to remain in the water for at least 20 years with minimal maintenance required. This offers an opportunity for marine life to settle on the cement blocks anchoring the seabed barriers, forming an artificial reef.



REVOLUTIONISING THE CONCEPT OF SHARK MANAGEMENT For Andreotti, the first commercial installation of the SharkSafe BarrierTM is the breakthrough the team has worked towards for the past 15 years. “We now have the technology to allow the rightful inhabitants of the oceans to survive and thrive and for sea-loving humans to enjoy their time in the water safely,” she says. This is a win-win situation, especially for areas that rely on ocean recreation as a main source of revenue, such as beach towns in South Africa, Brazil, New Caledonia, the Bahamas and Réunion, she concludes. For more information, to support this great truly South African initiative Or to arrange an interview contact Dr Sara Andreotti at or Tel +27 (0) 72 321 9198 for more information. Below: The SharkSafe BarrierTM team at KND Fabrications in Maitland, Cape Town, shortly after the parts for the 30-metre-long installation were packed, ready to be shipped to the Bahamas. In the front, from the left, are Laurie Barwell, Errol Bourne, Dr Sara Andreotti, Ronnie Adams, Kezia Bowmaker, and Nina Sirba. At the back are Louie Miggel, Anthony Mederer, Matthew Mtshabe, Lincoln Calbert, Dirk Zimri, Nicolo Farmer, and Ricus du Toit. The factory owner, Rory Bruins, was travelling internationally when the photo was taken. | PHOTOS by Wiida Basson

Alert Diver

Dive Safety

Pros Choose DAN Trusted When It Matters Most

Richie Kohler, Professional diver, shipwreck researcher, and film-maker, explains why he chooses DAN.



I was reading Sylvia Earle’s foreword to Our Ocean, Our Future: Palau, a lovely coffee-table pictorial book by Michael Aw, David Doubilet, and Jennifer Hayes. Earle opened by remembering when she was asked about the best place to go diving. Her usual answer is, “Almost anywhere, 50 years ago.” When asked the same question, my go-to reply typically begins by inquiring if they mean by liveaboard or a time machine. Our similar responses reflect the harsh reality that we’ve seen an alarming degradation of coral reefs in our short lives as travelling divers. I pondered what I’d see when revisiting Palau. When I first began international dive travel, I used to go to Palau every couple of years, but time and habits slipped away. I was surprised to find the conspicuous absence of a Palau folder in my digital archive, which meant that I hadn’t visited there since my 2001 conversion


from film to digital. There has not been another destination I was so past due to revisit.

know when to visit specific reefs to ensure divers can observe episodic behavioural phenomena such as spawning.

Against the global backdrop of ocean wildlife’s fight against industrial fishing practices, which Earle also highlights in her introduction, the people of Palau have been incredibly progressive. In 2009 Palau became the first country in the world to protect their sharks with a national shark sanctuary in their exclusive economic zone (EEZ). The effort ended all commercial shark fishing in more than 200,000 square miles of ocean. A year later, then-President Johnson Toribiong announced an expanded sanctuary status that included marine mammals, thereby protecting dolphins, whales, and dugongs.

DÉJÀ VU BUT BETTER Travelling to Palau is a bit of a slog from North America; most travel options pass through Guam and entail long transit times. We weren’t terribly disappointed to have an easy dive on the afternoon of our arrival to mitigate jet lag and fatigue. It still provided interesting photo opportunities and reflected evidence of the fierce fighting that these islands endured during World War II.

The most ambitious conservation initiative was the Palau National Marine Sanctuary (PNMS), which bans all extractive activity — including industrial and artisanal fishing — in 80 percent of the EEZ, an area larger than California. President Tommy Remengesau Jr. signed the law in October 2015. Since its implementation on Jan. 1, 2020, no other country has assigned marine protected status to such a significant proportion of their national waters. The efforts are working. The reefs and marine life I saw this year were better than anything I recall from the mid-1990s. I have no empirical baseline, just memory. Factors contributing to Palau’s coral health include geographic luck, prime reefs far offshore from the general population centres, the cleansing effect of ocean currents, national conservation efforts, and respectful divers. Another facet we can’t ignore is the improvement of the dive product. The dive operators have become skilled at watching tides and lunar phases to predict the right times to dive their reefs accurately. They also

Pacific islands were strategically important in early 1944 because they protected areas the Japanese occupied in the Philippines, Malaysia, Borneo, and the Dutch East Indies. Palau and nearby Peleliu were targets of relentless U.S. airstrikes, which sank more than 60 Japanese ships. Japan salvaged at least 27 wrecks to help pay their war reparations, but a considerable portfolio of historical ships remains for diving. These waters also hold many aircraft. Some sank after aerial dogfights, some from being strafed while at the harbour, and some from bad luck, which seems to have been the case with the “Jake” seaplane. Resting at 45 feet, just 10 minutes from the Koror dock, its wreckage has no bullet holes to indicate aggression or a bent propellor from striking the ocean surface at speed. A local fisher first spotted the plane’s outline on the seafloor in 1994 and informed a local dive shop. Paul Tzimoulis and Geri Murphy took the first underwater photos of it while they were in Palau to shoot a Skin Diver magazine article. It’s a beautifully intact aircraft sitting in a vast field of hard corals and festooned with colourful encrusting sponges. The visibility on our dive was only about 25 feet, but the sponge cloaking the propellor exploded with colour under a bit of strobe light.




BY LAND OR BY LIVEABOARD I hosted my group on shore for this trip, but previously I had dived Palau from a liveaboard. There are pros and cons to each option.

used a reef hook to hold a position at the second corner along the wall and wait for the grey reef sharks to pass near. That’s their typical protocol, but the variable conditions always define the dive in Palau.

The daily trips leave Koror in the morning and run 45 to 50 minutes through the protected and scenic Rock Islands to Palau’s iconic dive sites. Most boats do three-tank dives with a lunch break on the beach of a nearby island. Several of these islands have infrastructure, such as picnic tables and restroom facilities, making a day at sea less of a hardship — and you need some time to off-gas anyway.

We went to nearby Dexter’s Wall for our next dive, where we found an exceedingly calm cuttlefish impervious to our proximity. The bottom features are similar at many of the wall sites here, including the famous Blue Corner, which is only a few hundred meters away.

The liveaboards take divers to the same sites but can offer four dives daily because they can moor closer to the dive sites. Night dives also are easier to stage. The decision about which option is better for you is more about lifestyle preference than the dive portfolio. Even Peleliu diving is possible from land, but it is a longer run and much easier from a liveaboard. PISCINE PARADES Our first morning’s speedboat ride takes us 27 miles southwest of Koror to New DropOff. The crew tells us that currents can be strong at the site, but we arrive at slack tide and are treated to a very mellow dive. The reef starts only a few feet under the surface and is part of a vertical wall that runs the entire length of Ngemelis Island. The wall is nicely decorated with large, colourful sea fans and clusters of pyramid butterflyfish that exasperate me because I can never get near enough for the closefocus, wide-angle shots I envision. The schools of snappers and barracudas are far more tolerant of my approach. If the current were running, we would have

New Drop-Off is so good you will likely visit it a few times during a week’s dive itinerary. Our second dive there later in the week was absolutely worth it when we saw abundant turtles along the top of the wall in only 15 feet. Those with their eyes away from a viewfinder long enough to see the entire spectacle counted 18 green sea turtles in the shallows. They were so docile that I later commented to our divemaster that they were much more approachable than the ones we saw on subsequent dives in Peleliu. She wryly winked at me and asked which island I thought had a tradition of fishing for turtles. Blue Corner is the most famous dive in Palau, and it is undoubtedly impressive, but it is dramatically different depending on the current. Currents can suddenly change direction horizontally or vertically, so the divemasters instruct divers to tether to a bit of rocky substrate with a reef hook and slightly inflate their BCDs to lift off the bottom and avoid affecting living coral. The intense current has scarified the top of the reef, so the procedure is more ecologically benign than it sounds. Hooking in lets divers hover in place without exaggerated motion that might scare away the sharks. Skilled divers and the right current can allow proximity to grey reef sharks, a dive highlight.





Immense bumphead parrotfish and large schools of blueline snappers also aggregate here. Napoleon wrasses are common, and you can be rewarded with massive schools of bohar snappers if the lunar cycle is right. Most weeklong itineraries provide multiple dives at Blue Corner due to popular demand for the diverse piscine parade. The pantheon of the world’s top tropical dives includes the Ulong Channel, which is unique among Palau sites. This shallow channel through Ulong Island’s reef structure has a bottom of no more than 45 feet and coral and marine life in little holes that speckle the bottom and slopes along both sides. Sometimes, the current is swift, and sometimes you gently fin along the bottom during slack tide. Divers usually drop to 60 feet just north of the channel, which is a good spot for grey reef sharks. The incoming current funnels into the channel and presents a nice opportunity to photograph the sharks against a coral background rather than the deep blue backgrounds at most other wall sites. The dive’s defining feature is the massive cluster of lettuce corals vertically following the reef slope’s contour for almost 25 feet. It’s not only the coral itself that makes it so compelling, but also the countless small squirrelfish and damselfish that occupy this large coral condominium's little nooks and crannies. BUMPHEAD PARROTFISH SPAWNING This spawning event at Grassland might have been a secret at one time, but seeing 11 boats converge here so early in the morning suggests the word is out. The largest known spawning aggregation of bumphead parrotfish (Bolbometopon muricatum) happens with a monthly lunar phase if the tide and temperature are right.

As large numbers of bumphead parrotfish mill about in the shallows, anticipation builds in both the observers and the fish. The parrotfish move out to the sand bottom at about 80 feet as a curiously cohesive whole and then rush upward, females cheek-tocheek with the males. In a synchronized explosion, they release their eggs and sperm. Imagemakers must be at the right place and time to capture this dynamic dance of procreation. I ponder the well-known spawning aggregations and how few are truly protected. One pass with a purse seine net could wipe out a generation of fish, but thanks to the conservation conviction of the Palau government and the Palau dive fleet’s ongoing vigilance, this spawn is secure for now. Plan ahead if the bumphead spawning is part of your Palau wish list. Your dive operator will know when it will happen and can help you refine your dates. We did it on two consecutive days and were more productive on the second day after learning the event’s rhythm. MANTA MECCA In 1905, while Palau was a German colony, Germany realized the value of harvesting guano deposits from the seabirds on Angaur Island because of its commercial value as a fertilizer due to its high phosphate content. To efficiently get the cargo to the port for shipping back to Europe, a channel had to be excavated between the Ngemelis and Ngercheu islands. German Channel is now so shallow in some places that only speedboats with shallow drafts can confidently navigate it. Underwater, the channel has become a manta mecca due to several cleaning stations at just 45 feet. The dive guides know where to position divers, and it typically



doesn’t take long before mantas will queue up for their daily dose of hygiene. They are indifferent to the presence of divers, and proximity is probable for anyone patient enough to kneel in the sand and wait. We dived the German Channel several times, so the novelty of getting close to a manta faded over the week. But late one afternoon, we were treated to a remarkable frenzy of bohar snappers, rainbow runners, and manta rays as they converged to feed on a plankton-enriched current flowing through the channel. All the action happened in the top 20 feet of water, with the mantas making loops with their mouths agape and the massive schools of snappers greedily chomping away. We hoped for a repeat but never again had that synergy of conditions during our time on location. BACK AT PELELIU The last time I had dived Peleliu was at a site called Peleliu Express when I was much younger and less savvy about navigating extreme currents. I recall being alarmed when we were all swept off the wall to offgas in the open ocean. The dinghy driver was not surprised, and while the boat was a speck in the far distance by the time we popped our safety sausages, the pickup was routine. With that dive still on my mind 30 years later, we opted for the more sedate Peleliu dives at Peleliu Wall and the shallow reefs of Coral Gardens. Peleliu Wall was worth the trip from Koror for the colourful sea fans and soft corals adorning the drop-off and bathed in outstanding water clarity. However, it wasn’t as fishy as the more traditional sites off Ngemelis Island, and the marine life was noticeably more skittish. Coral Gardens offered excellent boulder and branching hard corals; while most were quite pristine, there was also evidence of

coral bleaching in the staghorns. One day in a week’s itinerary is likely enough for Peleliu. It’s a good site to experience, but many other options exist. Discretionary adventures in Palau usually include snorkelling in Jellyfish Lake, but we learned that the populations of golden jellyfish (Mastigias papua etpisoni) were underwhelming. Check with your dive operator for up-to-date information. Still, with the $100 snorkelling permit fee and the population decrease, we opted out of what is normally a highlight of any Palau adventure. The Palau Visitors Authority explained that the lake is sensitive to El Niño and La Niña weather patterns, which can affect the wind and rainstorms that help keep the lake cool. While we were there, La Niña was contributing to a water temperature too high for normal golden jellyfish reproduction. The weather will eventually be favourable for their life cycle again, and local knowledge will help inform visitors when it is right to add the activity back to their plans. HOW TO DIVE IT Getting there: Your international flight will arrive in Koror, and U.S. citizens staying less than a year don’t need a visa. Various fees are associated with diving Palau, including the dive permit ($100) and additional permits to dive Peleliu ($30) and snorkel Jellyfish Lake ($100). Conditions: Water temperatures are fairly consistent year-round, usually ranging from 82°F to 86°F. The drier season is from December to April, but an aerial view of the verdant Rock Islands reveals that rain is common throughout the year. Some sites are fine for novice divers, and excellent snorkelling is available among many of the Rock Islands, but expect current

at times and be prepared for it. Bring a reef hook and a surface marker buoy (SMB), preferably one you can deploy from underwater. Palau Marine Law requires an SMB for each diver. If time permits, visit the Chandelier Cave marine cave system, which comprises five separate but connecting chambers with dramatic stalactites, stalagmites, and a halocline. Several World War II shipwrecks and aircraft are accessible, and topside tours emphasize the conflict and its aftermath.


On the North-East coast of Zanzibar, in Matemwe, you will find the friendly and professional Dive Point Zanzibar diving centre. This PADI 5 Star resort has one of the most exotic views of Mnemba Island and from here divers can experience some of the best diving that Zanzibar has to offer. This dive centre is managed by Adam Sokolski. He is a scuba diving instructor and has become an excellent underwater photographer. “I am originally from Poland and came to Zanzibar by accident. My wife and I were offered a job here and we decided to accept it. That was many years ago, said Adam.





He began his diving journey in 1996 in Poland. Completing the two-week long CMAS 1 Star Open Water course was a hardcore training in a cold and dark Polish lake. Soon after that, he escaped the gloomy cold of Poland on a diving trip to Egypt. “It was an amazing experience. Diving became my passion, said Adam. “I took my first underwater photo with a small compact camera during a trip to Dahab in 2006.” Upon returning from this trip he entered the image in a competition, published in one of the Polish diving magazine. The photo of a seahorse was award the winning image as “Photo of the month”. Since then, he has done approximately 3000 dives in different places. Poland, Austria, Switzerland, Croatia, Egypt, Jordan, Zanzibar, Pemba, Mafia, Bali, Philippines and Malaysia to name but a few.




In 2013 he attended an underwater photography workshop in Anilao, in the Philippines. This opened his eyes and interest to the amazing world of macro underwater photography. “I love all those tiny creatures that look like aliens. I love the patterns, colors and variety of shapes. And, of course, the challenge of taking photos of such small things are rewarding.” It takes a lot of patience, excellent diving skills and a sharp eye to take good underwater macro pictures. The photographer needs to take care not to damage the reef around the subject, as his camera equipment can become a bulky assembly. “I use the Olympus OM-1, Micro Four Thirds digital Mirrorless camera, in Nauticam housing with INON Z240 strobes. My main lens is Olympus 60 mm macro. The advantage of my setup is its relatively small size. This system provides me with good speed and good quality photos. I am planning to do more wide angle, but still I prefer macro.”


“One of my favourite photos is of the Costasiella kuroshimae sea slug taken in Tulamben, Bali. Costasiellas are super cute, tiny creatures that resemble sheep and are one of my favourite subjects. Fondly also called Shaun the sheep nudibranch. This photo was published in the Polish edition of National Geographic, together with several other of my photos. That was one of the greatest moment in my photography life.” His favourite dive sites in Zanzibar (Tanzania), are Tumbatu Island and Shane’s reef. His preferred dive destinations are Anilao in Philipinnes and Tulamben in Bali. On Adam’s photography bucketlist there still are taking a perfect photo of the Leafy Seadragon found in Australian waters and diving at Lembeh and Ambon in Indonesia.


I still remember the night in late December. It was a full moon, and the wind was blowing all over the place as it often does when the moon is full. The moon, which is always exciting to stand and gaze at, was shining a deep crimson red just as it broke the horizon out over the sea in the late-night sky. The hospital was quiet after Christmas with many of the consultants, bar those working in emergency and tending to the wards, still being on their Christmas weekend leave. It was a lovely night to stand outside in the fresh air, marvelling at the view of sparkling lights over the Durban harbour and out to sea. The peaceful silence was shattered as the red phone on our reception desk rang urgently. Leaves chased me with the wind into the reception as I opened the door to answer the call. What a bizarre night it was about to be.

SANTA CLAUS GETS BENT HIGHLIGHTING THE SEVERITY AND COMMONALITY OF SKIN BENDS EDUCATION TEXT BY DENNIS GUICHARD Dennis Guichard is a multi-agency qualified Scuba Instructor Trainer & a DAN ‘Master Dive Pro’ member. He is a qualified Offshore Diver Medic, Saturation Life Support Technician, and an UHMS Hyperbaric Technologist.

Turns out the call was from the Netcare 911 paramedical team, who were currently up at Sodwana Bay attending to a diver who had felt unwell in the early evening after a few repetitive deep dives. The diver was pale in complexion and struggling to stand without falling over: that, combined with bouts of emesis (which is a more polite medical term defining the act of vomiting). It certainly sounded like a serious neurological or inner ear bend. We were asked to get our chamber ready for the patient and that the ‘HEMS Netcare 7 (NC7)’ helicopter was just about to start up for its low-altitude flight back to St Augustine’s hyperbaric facility in Durban (I’ve always imagined that must be the best job in the world doing low altitude flights along the stunning KwaZulu Natal coastline and getting paid for it). I always get excited when any diver presents at the chamber with suspected decompression sickness. Deco science is what brings us alive. It’s what we live for. It’s


more exciting than a new packet of biscuits, although I’m certainly partial to those too as my waistline will attest. But that’s got nothing to do with the story. All the patients’ stats we were given were that the diver was in his late 70s, somewhat overweight, had an extensive white beard, and was jovial despite the circumstances. His blood pressure was reduced (hypotension), he was struggling to urinate (oliguria), had cold clammy skin (hyperhidrosis), a racing pulse (tachycardia), and a large blotchy blue-purple rash around his substantial abdomen (Livedo Racemosa). Embroiled in excitement and anticipation myself, I put the phone down and put a call out to our stand-by chamber operator and double-checked that our doctor was activated and en route too. Our Xmas tree was sparkling away in the corner with a packet of mince pies still resting on the branches that a kind patient had left for the chamber staff to enjoy. I proceeded to get the chamber ready for use, checking the air

banks were at full pressure and all our necessary medical supplies were on hand for the patient's arrival.

I asked for, but now didn’t seem like the time to either ask difficult questions or panic.

A long drawn-out 2-hours later, ‘NC7’ landed on the roof of the hospital, and the patient was wheeled into our facility after a brief visit to the Emergency Room. It’s always the most exciting time, getting to see what it is that we might have to deal with. Getting the necessary paperwork in order, we asked the diver what his name was. And like out of a suspenseful 007 Bond movie, he told us in poor English, tainted with a heavy hint of Scandinavian accent, that his name was ‘Claus’... ‘Santa Claus’.

The term Decompression Illness covers both Decompression Sickness (DCS) and Arterial Gas Embolism (AGE). DCS may be caused by local bubble formation from excessively supersaturated tissues after dives. AGE, on the other hand, can be caused by ruptured alveoli in the lungs or by paradoxical embolism of venous gas bubbles bridging through into the arterial vascular system through a hole in the heart called a PFO (Patent Foreman Ovale).

For a moment, my mind raced in panic. I was glad I’d kept the Christmas tree lights on, but I wondered quite how much he might’ve known about me being either good or bad that year. It was also clear that a few of the mince pies had gone ‘missing’ in the time I was left waiting for his arrival. I also had a few questions in mind, like why I never quite seemed to get the presents


These tiny bubbles can then grow further as they come into contact with supersaturated tissues and/or elevated dissolved gas tensions within the blood. These bubbles can cause vascular inflammation, soliciting an immune system response, and/or can grow large enough to cause a myriad of tiny vascular blockages. One of the telltale signs of this malady is a mottled patterned rash which we refer to as Livedo Racemosa (LR),

more commonly known as a skin bend. Skin bends have long been regarded as a mild form of DCS. They should however be treated as a serious condition because of the severe potential of an underlying neurological complication. Some have postulated that skin bends may be caused by bubbles affecting the brain stem, resulting in the release of neuropeptides, which control vasodilation and vasoconstriction of blood vessels in the skin. Although this remains a controversial hypothesis. Skin bends, regardless, is a potentially severe manifestation of DCS that can, at times, be life-threatening if not managed appropriately. The condition can result in a significant loss of circulating blood volume, similar to what occurs in extensive burns or severe allergic reactions, potentially leading to lifethreatening hypovolaemic shock. Some patients with skin bends may require the administration of substantial intravenous fluids to counteract this shock during hyperbaric chamber treatment. It’s impossible to predict whether a skin rash will develop into a harmless, self-limiting ailment or a dangerous shock-inducing condition. Therefore, it’s crucial not ever to take one lightly if you experience one after a dive. There is a strong correlation between skin bends and the presence of a PFO in any diver. As many as 30% of us can have one, although only about 6% of divers are considered to have a PFO large enough to be problematic in diving. PFOs are central to many forms of DCS, and the challenge is we won’t know we’ve got one until we do bend. Santa’s dive profile wasn’t at all provocative. He followed a good slow ascent rate, did a

5-minute safety stop at 6m depth, and his peak surfacing gradient factor was only at 82%. Santa, however, had been working hard in previous evenings delivering presents to all the good children. He was exhausted and had certainly eaten too many mince pies stopping off at everyone’s home. Too many beers, left by desperate Dad’s, hoping not to get any more socks, had also exasperated his level of dehydration. And then just bad luck that it turned out he’d had this PFO since birth. In truth, DCS is rare, postulated to only occur in 2 in every 10,000 dives in warm water. But it can often be quite serious when it does occur. If you have a PFO and you align many of the predisposing risk factors, then you’re certainly inviting one to occur. Alcohol and diving don’t mix. Alcohol can lead to dehydration, and we know that it also interferes with blood serum surface tension. It also reduces surface tension in bubbles trying to make their way to the lungs to be expelled. Being overweight is also a predisposing risk for DCS. Some would argue that fat is a slow tissue and thus irrelevant in sports diving. Still, it does seem that skin bends (Livedo Racemosa) has a prevalence for subcutaneous fatty areas like the abdomen, chest, thighs, buttocks, breasts (man boobs), and upper arms. And Santa was a recipe in the making for all of these predisposing risk factors. All he wanted was to enjoy a few dives and some peace and quiet in the idyllic warm waters at Sodwana Bay. It was a good choice to make, and his rampant Ho Ho Ho’s certainly livened up life on the beach. But it just wasn’t his day, and despite doing everything seemingly right, he got the bend regardless. DCS is like that.

Many questions remain. Why Santa had to take the ‘Netcare 7’ helicopter back to Durban instead of just catching a lift on his sleigh? I can only suppose that his reindeer, too, were off sauntering through the iSimangaliso Wetland Park, fraternising with our local zebra and blesbok. Whether he gifted himself his own full set of scuba gear or whether he just rented locally. You’d hope that anyone would always rather have their own kit to use, but I suppose he might not have had space in the boot of the sleigh for all of it. Santa responded well to a US Navy Treatment Table 6 session in the chamber and 6 litres of IV fluids. After annoyingly finishing off my pack of mince pies, he was released to make his way back north. All’s well that ends well. From me, I wish you all a very Merry Christmas and all of the very best for a very exciting New Year and all that 2024 might bring. I’m hoping I might get a better present from Santa this year, but I won’t hold my breath. Enjoy your diving. Stay safe out there.

FESTIVE SHOPPING 30 SOUTH | MEET THE VENTURAS RE Sustainable Eyewear for Adventurous Lifestyles | Made from 100% recycled ocean plastic. RE N6 Frames. Made from 100% recycled fishing nets, N6 is ultra-flexible, super lightweight, non-slip, non-abrasive and hypoallergenic. HDo (High Definition Optics) lenses: Our cutting-edge HDo lenses use NASAdeveloped REVO coatings to ensure high-contrast viewing and enhanced clarity. They are ballistic-grade shatterproof, hydrophobic, and highly scratch resistant. Protection-wise they filter 100% of harmful UV Rays, are Anti-Glare and CAT 3 Polarized. Lifetime Guarantee – Our recycled Sunglasses have a lifetime guarantee on all the frames. Learn more HERE

FESTIVE SHOPPING 3SQUARE DIGITAL DESIGN AND FABRICATION 3square is a digital engineering and fabrication plant focused on providing top quality, customised and affordable undersea solutions to marine explorers and content creators. Our unique production process coupled with over three decades of undersea experience makes us the first choice for professional explorers, NGO's and weekend divers. The revolutionary underwater support and stabilization system specifically designed for GoPro series cameras. This robust device features a unique donut shape, enhancing its stability underwater. It is equipped with four one-inch ball joints, providing versatile options for mounting lighting and other accessories. Both the GoNut and the DoNut includes an innovative 'dog bone' trigger, allowing photographers to effortlessly capture shots using either their thumb or forefinger, enhancing the ease and flexibility of underwater photography. Check out much more at

FESTIVE SHOPPING WADDLEON BY MARTS Lovingly designed and inspired by our founder Martine VIljoen’s years of working with their real life waddling counterparts. These experiences are where penguins truly stole Martine’s heart, driving the passion to contribute to helping these critically endangered animals in every way she could. Our socks are officially available online on the SANCCOB online store, selling at R120.00 per pair of WaddleOn! Our current sizing is UK 8-11 and UK 4-7 for all of the 8 sock designs (NEW KIDS UK 6-8 sizing for our Heel and Toe designs) The initial collection consists of 4 complimentary pair designs and introduces wearers to Rocky (at SANCCOB) and Ms Harold (at Two Oceans Aquarium). The ultimate gifts for penguin lovers and funky sock collectors alike. See the variety available on istagram @waddleonsocks

FESTIVE SHOPPING SALTEEZ Passionate about scuba diving? Looking for unique apparel that reflects your love of the ocean? Our shop is dedicated to providing ocean-inspired clothing to scuba divers. From tshirts, hats, hoodies to flip flops and yoga leggings and other accessories, we have everything you need to take your passion for scuba diving to the next level. Each design is a tribute to a specific ocean creature. Our flip flops are made from premium rubber for the best comfort and fashionable slim cut. With SALTEEZ you don’t have to settle for the ordinary be different be bold! Join our community of avid scuba divers and beat the ordinary. Shop online at Salteez Ocean Shop for apparel that truly reflects your passion for the ocean. Get in touch at or on instagram

FESTIVE SHOPPING CHONDRICHTHYA Introducing the innovative sustainable clothing collection that blends science and fashion seamlessly. This unique line features hoodies and t-shirts adorned with intricate scientific shark anatomy drawings, combining art and education. Each garment is crafted with utmost care using eco-friendly materials, such as organic cotton and recycled polyester, reducing environmental impact. The anatomical illustrations showcase the fascinating inner workings of these majestic creatures, serving as a conversation starter and a testament to marine conservation. With this collection, fashion enthusiasts can proudly don stylish apparel while spreading awareness about the importance of protecting sharks and their ecosystems. Embrace sustainability and scientific artistry with this captivating and conscious clothing range. The eco-friendly shark-inspired brand. With sustainable designs, every purchase supports shark conservation and research. Wear your love for sharks and the planet proudly with Chondrichthya. See them at

FESTIVE SHOPPING DIVE ACTION Dive Action is your one-stop shop to fit all your dive needs. From scuba diving courses, dive charters and gear servicing to all the latest diving equipment and accessories available. Our friendly and knowledgeable staff are more than willing to help you with any equipment and training queries you may have. Highlighted Dive Products 1. Aqualung Duetto Black Mask - R1150 2. Aqualung Small Squeeze Blunt Tip Knife - R1195 3. Aqualung Snappy Coil - R650 4. Dive Action Reel 50m - R1150 5. Sodwana Bay 2 Mile Reef Dive Guide Book - R250 6. NXT Level Wetstuit Wash 500ml - R150

COVER THROUGH DAN LIFESAVING BENEFITS - 24/7 EMERGENCY HOTLINE - ACCESS TO DIVE MEDICAL EXPERTS - DIVING RESOURCES TO KEEP YOU SAFE Your gateway to dive safety services & worldwide dive coverage at low annual rates!





WHEN SHOULD I PHONE THE DAN HOTLINE? All diving emergencies Non-diving medical emergencies Diving medical information, such as fitness to dive, medication, and travel medical advice and enquiries Travel notifications and advice Diving medical examiner contact details International medical centres or doctors who want to confirm DAN memberships WHAT DO I NEED TO HAVE READY? The caller and/or patient’s name and contact number The nature of the emergency The patient’s DAN membership number, if applicable or known The patient’s medical aid information, if the incident occurred within South Africa The patient’s travel insurance information, if applicable

If the caller is not at the scene, at least one local contact number should be provided in order to reach the person that is in need of assistance, or those who are in charge of their care.

WHAT HAPPENS AFTER I HAVE LOGGED THE EMERGENCY? DAN makes a conference call to one of the on-call diving medical officers (DMOs) when an emergency call is received and the nature of the event has been established. The DMO will provide specialist diving medical advice regarding how and what should be done immediately and will also make decisions concerning the further management of each case, depending on the situation. WILL I GET EVACUATION BY AIR? Aeromedical resources, such as helicopters and air ambulances, cannot be dispatched unless authorised by the DMO. It may take longer to activate an air ambulance than it would take to mobilise emergency medical services via a ground ambulance. Several factors, aside from costs, will determine aeromedical evacuation.

The DAN hotline provides emergency medical assistance to injured divers. We encourage you to call early, even when you are uncertain, rather than wait until the situation has become critical as the opportunity to assist becomes more restricted.

TRANSPORT THE AVAILABILITY OF TRANSPORT Is an air ambulance or a helicopter available?

THE INJURY THE NATURE OF THE INJURY How urgently does the patient need advanced life support and should they be moved to intensive care?

THE LOCATION THE LOCATION OF THE PATIENT What are the optimal logistical considerations for efficiently and safely moving the patient to a place where they can receive medical assessment and appropriate medical care, with appropriate medical support, during the transfer?

LANDING ZONE VARIOUS ASPECTS REGARDING THE LANDING ZONE OR AIRPORT Are these appropriate for a helicopter or a fixed-wing air ambulance? Are these open, particularly at night? What are the customs or immigration requirements? What are the implications of getting the patient to the landing zone or airport, or the crew to the patient?


PARTING SHOT ADAM SOKOLSKI LEMON GOBIES I have been diving for 27 years. Diving has been my job for a long time, but it has never stopped being my passion. A passion that allows me to visit strange and fascinating places. I love watching and showing others the diverse underwater world and its inhabitants. I took my first underwater photo with a small compact camera during a trip to Dahab in 2006. From then on, underwater photography became an important element of my life. I always have my camera underwater. For me, underwater photography is an endless journey of searching for the perfect shot, improving my skills, and buying more and more photo equipment. I have been associated with Zanzibar for many years, but trips to Asia opened my eyes to the fantastic world of macro. I love these strange microscopic creatures that look like aliens. These Lemon gobies in their bottle home were photographed in Anilao, Philippines.

Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.