DOF Subsea: Inside disaster deep-sea dive that caused workers’ brain injuries

What should have been a proud milestone for Australia’s oil and gas industry — the deepest commercial dive off our shores — became an abject and almost deadly lesson in management failure. The calamitous operation, which caused some of the divers debilitating brain injuries, was revealed by The West Australian five years ago. On Tuesday, Perth-based diving company DOF Subsea Australia was convicted in the Magistrates Court on three counts of negligently breaching its health and safety duties under laws governing the offshore industry. Following the conclusion of the case, The West Australian can tell the complete story of what went awry and how easily the debacle could have been averted. The failures serve as a wake-up call to an industry that talks tough on health and safety, but doesn’t always live up to the standards due to a macho culture and fear among workers that they’ll be seen as weak or lose their lucrative jobs if they speak up. For several elite divers, it was a descent to an underwater world of pain and disorientation at depths of up to 270m. While some have recovered, a few are still suffering five years on from a condition called high-pressure neurological syndrome (HPNS). Symptoms include visual disturbances, dizziness, shivering, vertigo, anxiety, nausea and cognitive impairment. Dr Ian Millar, a specialist in diving and hyperbaric medicine at the Albert Hospital in Melbourne, examined 13 of the 15 divers on the Deep Sea Diving Project. Dr Millar said HPNS susceptibility can vary individually and that it appeared some people were HPNS resistant. This explained why the divers had different experiences, with some reporting mild impairment while others found it disabling. In his judgment, Magistrate Tom Hall accepted Dr Millar’s evidence that HPNS can cause lasting effects in the more severe cases. HPNS is a risk associated with dives beyond 150m and increases with the speed of compression. The slower divers are pressurised to work at such depths, the less chance they have of developing HPNS. The mission of the divers on the DSDP was to carry out repairs to clamp connectors on a major pipeline off the north-west coast of WA, in the Ichthys field, about 460km offshore from Broome. The pipeline’s operator INPEX engaged McDermott Australia, which in turn sub-contracted DOF Subsea to provide diving services. In saturation diving, the divers live in a small pressurised environment — a hyperbaric chambers on a ship — where their body tissues are saturated with dissolved gasses, enabling them to carry out multiple bell runs to the ocean floor without having to decompress each time. The process of compressing the divers is referred to in the industry as “blowing down”. The crux of the criminal prosecution was the speed at which the men were blown down on the DSDP. The 15 divers were split into two groups, with the nine “group A” divers being blown down first on June 21, 2017. Their blow down to a “storage depth” of 224m took eight hours and two minutes. Six “group B” divers climbed into their saturation chambers a few days later on June 29. Despite being assured by diving manager Mike Paton — after HPNS issues came to light with the Group A divers — that their blow down would be slower, they reached the same depth in five hours and 22 minutes. Magistrate Tom Hall accepted expert evidence that industry best practice would be between 16 and 24 hours for the blow down. Ben Rossier was among the divers hardest hit and continues to struggle today. He told the court how he felt after his team of three men were blown down. “Well, it is quite incredible,” he recalled. “Violent shaking my body went from very hot to very cold. I had visual disturbances, auditory disturbances. The best way I can describe it it’s very similar to like in a war movie. When you see a bomb go off and a guy is sort of standing there looking around. Very, very similar to that.” He said he wasn’t able to stand very well, not without support, and had severe tinnitus as well as a lag in his vision: “A gap between what’s happening and how your brain is processing it”. His symptoms eased during his 26 to 27 days in the saturation chamber. However his life didn’t return to normal when he went home. Like some of the other divers, he experienced strange blackouts. “(On one occasion) I woke up in the middle of traffic on the other side of town standing in the middle of the road,” he said. “I fell to the floor, an old man helped me to the side of the road. I broke down in tears. I called my father and said I need to go and get myself checked out.” The court was told his ongoing symptoms included depression and anxiety, PTSD, insomnia, no mood regulation and panic attacks. Mr Rossier said it became apparent that “we were all suffering some problems” when he attended another job for DOF in Vietnam, three months after the DSDP. Another diver Marcus Kenny, one of the Group B divers, was the first to raise the alarm, electing not to dive and reporting his symptoms to DOF’s medic Mark Sinclair. He was sent to Dr Millar in Melbourne for assessment. The results prompted DOF to launch an internal investigation and notify Australia’s offshore regulator NOPSEMA in November 2017. More divers came forward. NOPSEMA received complaints from seven of the divers, advising of neurological injuries sustained during the DSDP, prompting its own investigation. Mr Kenny, who wasn’t called to give evidence in the trial, was among the most impacted divers. Another diver, not called, was Chris Tanti. Mr Tanti described his ordeal to The West Australian in 2019. “I couldn’t walk properly. I was cross-eyed. I was shaking uncontrollably. I had vertigo,” Mr Tanti said. Two days into the dive, the Mandurah father-of-two messaged his wife: “I am right on the edge of human survival here. I feel dazed and confused, I don’t know how much of this I can handle.” In a report, Dr Millar said it “was critical that divers not be deployed into the water after compression until symptoms of HPNS have settled with a period of rest, depth acclimation and observation.” Both Mr Rossier and another diver, Michael Kotchovsky, told the court they were bullied by managers over the intercom during their diving excursions. They alleged they were pushed to work harder and faster despite suffering from HPNS. On one excursion he said he needed every ounce of his strength and resolve to climb back into a diving bell after being caught in a fierce current on the ocean floor. “It was face to the sand, pulling yourself back (to the bell) inch by inch,” the 48-year-old told the court. An emotional Mr Kotchovsky said he experienced “twitching eyes, distorted vision, trembles, muffled hearing and balance issues”. “All those problems existed all the way through (the project),” he said. Asked to explain his persisting symptoms by prosecuting counsel Chris Shanahan, Mr Kotchovsky said: “I get confused easily. I can’t be out in loud environments with lots of people. I’m super quick to anger. I don’t drive very far any more. I don’t drive at night with bright lights. I just can’t handle it. “I still have balance issues going on. My memory is completely shot. Everything’s written down in a diary or on post-its. I’m heavily medicated all the time now.” Mr Hall described Mr Kotchovsky as a “compelling witness”. Another diver, Ben Miller, gave evidence that after one of his bell excursions, he told a supervisor he felt he was “only running on 60 per cent cognitively”. After the DSDP he felt a bit foggy, with shakiness and chattery teeth. He felt fatigued and overcome with headaches. He’d even withdrawn from social activities. “I can’t ever dive — any type of diving again,” he said. “(The DSDP) has affected every part of my life”. Diving manager Mike Paton called the shots from the Skandi Singapore, a state-of-the-art diving vessel, which housed the saturation chambers and from which the diving bell was lowered through a moon pool. His immediate boss, based in Perth, was John Rossier, then-general manager of operations. Magistrate Hall accepted evidence that Mr Paton and Mr Rossier combined, came up with the controversial compression rates for the “excessively fast” blow downs. “I am satisfied that Mr Paton and Mr Rossier both shared responsibility, though on the evidence before me it is impossible to say to what individual extent,” he said. Mr Rossier, who left the company soon after the DSDP, is the father of injured Ben Rossier. He told the company he agreed his son and other divers had been significantly affected. It had taken a massive emotional toll on him. “Unlike Mr Paton, I found John Rossier to be a credible and generally reliable witness,” he said. DOF had never dived beneath 200m before. In drawing up a compression rate, Mr Rossier and Mr Paton were guided by rates in the US Navy diving manual. The US Navy rates set out a range of rates, depending on the operational urgency. DOF applied a compression rate at the faster end of the range. Expert diving witness Ray Farrier explained US Navy rates were for military operational requirements and not for commercial use and that the faster end rates were reserved for “extreme cases based on operational needs”, such as a submarine rescue. “It is clear that DOF used extremely fast compression rates for both groups of divers without any evident operational need,” Mr Farrier stated in his evidence, which Magistrate Hall accepted. Had DOF used the slowest rates in the US Navy diving manual, the blow down would have taken 1469 minutes, instead of the 310 minutes it took the Group B divers. The times taken using the rates of rival companies Technip and Subsea 7 are 904 minutes and 984 minutes respectively. Mr Hall agreed that a diver experiencing the effects of HPNS potentially places himself and his fellow divers in danger given the high risk nature of saturation diving. Dr Millar said the “very rapid” blow downs presented “a significant risk of severe HPNS in a least some individuals if not all of them”. Most of the negative findings in Mr Hall’s judgment were directed at Mr Paton. Chief among them was that he didn’t slow the Group B blow down as he assured the divers he would. He failed to communicate the intention to Life Support Supervisor Allen Wallace, who performed the blow down. DOF had engaged Dr Phillip Bryson, a hyperbaric medical specialist based in the UK, as a medical consultant for the DSDP. Dr Bryson had asked Mr Paton to email him the compression rates and other details in advance. Mr Paton didn’t do so. He also failed to share any of the post-compression reports or post-dive questionnaire forms submitted by the Group A divers with the ship’s medic Mark Sinclair, Dr Bryson or any of the life support staff, even though it was apparent some had HPNS. Mr Paton gave evidence that his understanding was that HPNS was a temporary condition and not a long-term risk to divers’ health. “I find that Mr Paton was mistaken in these views about HPNS. Had Mr Paton been properly medically informed about HPNS, he would have appreciated that this is not necessarily the experience for every diver,” he said. “In my view, Mr Paton’s underestimation of HPNS was reflected in his dismissive attitude towards Dr Bryson’s involvement DOF had an opportunity to engage and consult with Dr Bryson on these very issues before any diving occurred and failed to properly do so. “Despite Dr Bryson’s request to be informed of the compression rates and hold periods proposed, he was not consulted about these things and as such DOF did not receive his medical advice on these matters. They should have. Mr Paton’s attitude towards Dr Bryson is further reflected in his telling (ship medic) Mark Sinclair not to talk to Dr Bryson, saying that Dr Bryson was “just trying to make a name for himself”. Another sign of Mr Paton’s attitude was his failure to share the post-compression reports with Dr Bryson. “Mr Paton agreed he didn’t think he needed any expert opinion to assist him in assessing the HPNS symptoms. I am satisfied that Mr Paton erred in not obtaining expert medical advice regarding the reported HPNS symptoms in the Group A divers,” Mr Hall said. “Mr Paton said he did not share the post-compression reports, or a summary of them, with Dr Bryson because he didn’t see anything alarming in them. “This evidence is not credible. For experienced divers, who have never experienced HPNS symptoms before to now be having HPNS symptoms is, in my view, a concern in itself and is ‘out of the ordinary’. At the very least it shows that Mr Paton did not have a full and competent understanding of HPNS and its potential seriousness. “(Mr Paton) admitted he did not intend to share (the post-compression reports) with the diving superintendents, the diving supervisors, the life support supervisors or the life support staff on board the Skandi Singapore because ‘I wanted (them) dealt with as a private document with regards to their medical conditions’. “Mr Paton’s concern (they) be kept private because they contained confidential medical information is without merit. In all the circumstances, this information is potentially critical information. “On my assessment of the evidence, I am satisfied that Mr Paton made a ‘blanket’ decision not to share the (reports) with anyone.” One thing Mr Paton did do to mitigate the risk of HPNS was extend the hold period by six hours for the “group B” divers once they’d reached 224m. But he didn’t notify Dr Bryson. “(It) begs the question why didn’t Mr Paton share this information with Dr Bryson?,” Mr Hall said. “Why didn’t he also share it with the diving support team and the life support team? In my view, the answer is that Mr Paton thought he could handle it himself without anyone else’s involvement.” Mr Hall noted the extended hold period wasn’t communicated to Mr Wallace until after blow down had occurred and “the manner and timing with which it was communicated for such a serious matter, is concerning to say the least”. “This lack of effective communication by Mr Paton to the diving and life support staff is a common theme arising from his management of the DSDP,” he said. In regard to the fast blow downs, Mr Hall said DOF had access to comparable rates used by an industry peer. “DOF failed to properly assess this information and to compare other industry peer compression rates,” he said. “DOF should have appreciated the context of the (US Navy rates) and introduced a slower rate or a range of rates to not do so was clearly negligent in all of the circumstances and clearly falls short of the standard of care that a reasonable person would exercise in the circumstances and is of such a high risk that it does merit criminal punishment.” Mr Paton agreed both blow downs could have been much slower. He agreed there were no time pressures and that they should have adopted a cautionary approach. Magistrate Hall acknowledged the evidence of several divers that they downplayed the severity of their symptoms in the post-compression reports, because they didn’t want to come across as weaklings or put their future employment at risk. For example, Mr Kotchovsky recorded his HPNS symptoms as 0/10. He explained the culture among saturation divers. “It’s a tough industry. You work years and years to get a good reputation and then you work even harder to hang on to that reputation,” he said. “As a diver in our industry that if you have any history of anything happening to you on a dive, be it physically or mentally or anything like that, then you are going to get shunned. “You’re not going to be employed ever again. It doesn’t matter if you go to a different company. No one wants to employ a diver who has broken once.” The company will be sentenced next year.

DOF Subsea: Inside disaster deep-sea dive that caused workers’ brain injuries

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