NUNO GOMES GENEROUSLY donated his Guinness Book of Records wall certificate to the Dahab dive centre that supported his epic world record dive to 318.25m.
On a return trip a year later, I noticed him smiling at the certificate, no doubt reflecting on fond memories of that historic day, 10 June, 2005, when he became the deepest diver in the world.
After that, it seemed, that world stood still.
From early in the millennium there were a number of deep trimix record projects in the offing. I was fortunate enough to be a part of some of them in the Red Sea as a support diver and, later, as a project manager.
These involved the Red Sea record, a world-record deep trimix attempt and the successful deepest wreck dive.
The events were well-sponsored, well-organised and almost evolutionary in developing better and safer methods for handling the challenges of these giant dives. I like to think that the popularity of these projects contributed to the enhancement of the industry that now sees 300m-plus dive computers and lights in production.
It was therefore all the more surprising that world-record dive attempts ceased completely for several years. Did the human race settle for what it had Did Gomes’ 318.25m dive seem too big a milestone to pass

BREAKING THE WORLD RECORD for the deepest dive is like baking the perfect cake, but the ingredients are gas calculations, physiology, temperature exposure, instrumentation, equipment choice, weather, support crew, decompression schedules, fitness training, mental preparation, finance and sponsorship, media coverage and nerves of steel.
The “pool” for such athletes is tiny, and only a small handful of these exceptional individuals exist. One of them is Ahmed Gabr of Egypt, who, on 18 September this year, calmly, silently and seemingly flawlessly took competitive scuba-diving’s greatest prize by reaching a depth of 332.35m. Finally the wait was over. A new star emerged.
The project had some similarities with the big events of a decade ago, but the big difference between this and previous attempts was that the primary diver was Egyptian and broke the world record in his own country in front of a home audience.
The international deep-diving community has boasted many big names in the past, such as Sheck Exley, Jim Bowden, John Bennett and Nuno Gomes, but few had heard of 41-year-old Ahmed Gabr until word began to spread earlier this year of a new world record trimix dive attempt.
Behind every great record lies a great team, and Gabr’s key support came from H20 Divers in Dahab, with a 30-plus international team headed by Sam Helmy and Jaimie Browne.
Dahab is fast becoming the haven for record-breakers, both in freediving and tec-diving, and on busy days the nearby Blue Hole is awash with many current and former champions.
Gabr’s dive took 13 hours and 50 minutes. His descent took 14 minutes and his deepest support was at 110m, which was where Browne met him on the way up.
The method of choice in previous record attempts has been to carry out a number of deep build-up dives to test the rig and the support team, and expose any areas for improvement.
As on other projects, Ahmed’s final deep build-up dive was in the low 200m range, reaching 220m a few weeks before the big day.
It seems that divers prefer not to conduct training dives closer to the record itself, even though it leaves a “gap” of more than 100m where very few have been before.
Most of the 20 deep training dives were beyond 140m. Some deep air dives were also made to maintain narcotic tolerance, but Gabr’s equivalent narcotic depths (ENDs) were lower than others had used on their record dives.
Trimix divers are well able to mitigate the effects of oxygen toxicity and nitrogen narcosis by reducing the oxygen and nitrogen contents of the mix. For a 300m dive, however, the oxygen percentage in the mix could be as low as 4% and the nitrogen lower than 14%.
The helium content at over 80% is huge, and while it has none of the narcotic or toxic effects of the other gases, such high percentages at depth have resulted in a condition known
as High Pressure Nervous Syndrome (HPNS).
HPNS signs and symptoms include dizziness, nausea, vomiting and the tremors. And this is where the perfect recipe comes into play.
A slower descent will reduce the effects of HPNS, but the downside is that more gas is consumed, and the already extensive dive schedule is lengthened further. More nitrogen in the mix also reduces HPNS symptoms, but of course it can lead to greater narcosis at depth.
HPNS differs from person to person, and is still not fully understood, but it occurs largely in the neurological or nervous system.

AHMED GABR EMBARKED on a heavy training programme of physical and mental fitness, involving yoga, cardio-vascular and muscle-building exercises. It is the body and its circulatory systems that absorb and eliminate the gases, and at this extreme level it must be in peak condition.
The dive is therefore a balancing act – not too slow, not too fast. Change one ingredient and then you have to change many more, such as the decompression schedule to accommodate other adjustments. It’s like trying to solve a Rubik’s Cube without the formula!
The target depth was 350m, but as the onset of HPNS intensified Gabr made the decision to turn back after reaching 335m – easily clearing the previous record.
Few have published their decompression schedules for these monster dives. The last two record-breaking schedules were closely guarded secrets. “It’s all proprietary at this stage,” says project manager Sam Helmy, and who can blame him Coca-Cola famously guards its legendary recipe too.
“Many months of meticulous planning have gone into this dive schedule and much of it was personally tailored for Ahmed’s physiology,” says Helmy. “We also had a tailored isobaric counter-diffusion avoidance calculation.
“There were no regular gas switches below 200m, and we used a variety of different programs to calculate our final plan.”
Lights have also been an issue on previous records but the selection of Tektite Trek 4s, each rated to 610m, held good. Ahmed wore a Bare drysuit and OMS dual-bladder wings and breathed from Apeks Tech 3 regulators.
Proof has been an issue on a number of previous sub-300m record attempts, two of which have involved run-times several hours shorter than the officially verified dives of Gomes and Gabr.

WHILE SOME DIVE-COMPUTERS are now rated to well over 300m, nobody has actually tested them successfully beyond that depth before. The dive was therefore conducted with dive-computers and a tagged rope.
“Our rope was sent to Cairo University, where it was tested for strength, shrinkage and elasticity in water and on land,” said Helmy.
“The Egyptian measurement and quality agency then used this report to measure the rope and mark all the relevant points on the line.
“The Guinness World Records official adjudicator, Talal Omar, remeasured the line and the marks independently after that. One of Ahmed’s computers bottomed out at 330m, but he went on to retrieve the 335m tag.
“The Guinness adjudicator established a final record of 332.35m owing to a slight rope bend, and that is the record that stands.”
The record is significant, because not only is it recognised by Guinness but it exceeds the nearest claimed record that Guinness did not verify due to lack of evidence. I asked Sam Helmy what special skills and scenarios were practised for the world record attempt.
“One of the reasons Ahmed was in such great shape when getting out of the water [he stood up and saluted everyone!] was the removal of his huge quad-tank configuration of 20-litre steel manifolds.
“This was achieved after five hours into the dive, leaving him in an X-Deep sidemount rig that took an enormous strain off his body for the remaining eight hours.
“All the support divers had to do was swap his old tanks for new ones by clipping them onto the easily accessible new rig.”
Nuno Gomes in 2005 famously kept his main rig on for the duration of his epic dive, which was all the more punishing in the high swell and surge penetrating the depths of his final decompression stops.
“The team practised this endlessly, sometimes without Ahmed – occasionally using a support-diver to take over the role. Emergency back-up on the day was substantial, with two onboard doctors including a hyperbaric medical specialist of Deco International, two paramedics and an ambulance and chamber on standby.”
The all-important sponsorship of this event was both an Egyptian and international affair, with National Bank of Egypt leading the field along with Petroleum Marine Services and Seahorse UAE providing 65 j-cylinders of helium.
Internationally, X-Deep and Stansted Fluid Power contributed to the successful project.

SO WHY HAVEN’T we heard much about Ahmed Gabr on the world stage before “Quite simply, it’s classified!” Sam Helmy told me. “Not by us, but he’s a special forces diver and most of his diving activities were for the military.”
Ahmed Gabr is 41 and began his technical diving in 1997. Much of his inspiration came from Dr Ahmed Kamal, a sub-200m diver and director of TDI Middle East.
Dr Kamal was there to congratulate his protégé on the big day, along with a crowd of more than 300 people who had gathered to meet the dive-boat, which finally berthed alongside the small wooden Dahab jetty at 1am.
“The night turned blue with camera flashes, and the almighty cheer that went up when he stepped on to dry land was deafening,” said Helmy.
For me, the world’s deepest-ever scuba dive is an A-lister among records and right up there with Felix Baumgartener’s famous leap from space.
Ahmed Gabr has also elevated Egypt on the world stage of scuba-diving with his monumental achievement. A documentary about him and his record dive is due for release in January.,