Byford Dolphin Disaster

One wrong move in a pressurized diving system can turn routine maintenance into an instant mass casualty event. We’re telling the story of the 1983 Byford Dolphin saturation diving accident, a North Sea offshore drilling rig disaster that shows how razor-thin the margin is when humans work hundreds of feet underwater under extreme pressure. 

We walk through what saturation diving actually is, why divers live sealed inside a hyperbaric chamber for weeks, and how a diving bell and trunk system acts like an airlock between two pressurized worlds. Along the way, we break down decompression sickness in plain language, including why dissolved nitrogen can become deadly bubbles if pressure drops too fast. It’s uncomfortable to think about, but understanding the physics is the only way to understand the stakes. 

Then we get into the night of the accident, the transfer procedure that’s supposed to keep everyone safe, and the catastrophic moment when a clamp is released before the system is ready. From there, we zoom out to the investigation, the push to frame it as simple human error, and the uncomfortable reality of outdated equipment and missing fail-safe interlocks that could have prevented a hatch from being opened under pressure. We also talk about what changed afterward, why North Sea divers and families kept pushing for accountability, and why robotics and ROV technology may be the best answer for the most dangerous subsea jobs. 

If you want more true disaster history, offshore safety lessons, and clear explanations of how these failures happen, subscribe, share this episode with a friend, and leave a rating or review.

Facebook: historyisadisaster
Instagram: historysadisaster
email: historysadisaster@gmail.com

Special thank you to Lunarfall Audio for producing and doing all the heavy lifting on audio editing since April 13, 2025, the Murder of Christopher Meyer episode https://lunarfallaudio.com/

Transcript

Scuba Dreams And A Dark Turn

SPEAKER_00 0:00

Scuba diving sounds fun. It's definitely on the old bucket list. I've had the opportunity in the past to go, but opted to go do something else instead. One day though, I plan on changing that. Getting to go under the open water and experience the ocean from a different perspective just sounds exciting. What doesn't sound exciting though is saturation diving. Going down hundreds of feet beneath the surface to work, plus having to live in special chambers for weeks at a time to avoid having to go through decompression every time you come back up. Just does not sound like a good time. Especially knowing that everything has to line up and be perfect. One tiny mistake, one little error, can spell doom and lead to a horrific death. Like what happened in 1983 on the Bifur Dolphin that led to the deaths of four experienced divers. So, what happened? I'm Andrew and this is History's A Disaster. Today we're diving into the frigid waters of the North Sea for a diving accident on the Bifur Dolphin drilling rig.

Pirate Bob’s Shrimp Break

SPEAKER_00 1:13

And tonight's episode is brought to you by Pirate Bob's All You Can Eat Shrimp Buffet. Pirate Bob's All You Can Eat Shrimp Buffet features all kinds of shrimp. From the firm and salty brown shrimp all the way to the lobster of the shrimp world, the rock shrimp. So if you got a taste for some shrimp, come see Pirate Bob. All the shrimp, all the time. The

The Biford Dolphin Rig Explained

SPEAKER_00 1:38

Bifer Dolphin was a semi-submersible drilling rig built in 1974 at Acre Verdall Shipyard by the Acre Group and was owned and operated by the Dolphin Drilling Company. Now it's considered a semi-submersible because while a significant part is above the water, there's a lot going on underneath the sea. Above the water is the elevated platform from which most of the work is done. Below is the ballast tanks that keep the whole thing stable. And while it had its own engines, they were really only good for fighting the ocean current and staying in place. Can't be drifting off anywhere. But for long distances, it had to be towed around by little special tugboats. Being a drilling rig, it could drill down to nearly four miles beneath the ocean. Being able to drill down that far would often require repair work and whatnot to be carried out deep down in the ocean, which required saturation divers. Divers that would be able to stay under immense pressure for long periods of time, often weeks at a time, which is extremely dangerous. They

Why Saturation Diving Is Dangerous

SPEAKER_00 2:50

worked around a depth of 300 feet below sea level, and the pressure down here is roughly nine times higher than at sea level, which comes out to about 132 pounds per square inch of pressure pushing down on your body. As the diver goes down deeper, nitrogen gas that's normally in the body starts to dissolve and enters the bloodstream. And since it doesn't get used up in the body, it just keeps building up, which is normally fine as long as the pressure remains. However, it becomes a little bit of a problem when say you, you know, want to come back up. On the way back up, if you come up too quickly, the nitrogen doesn't have a chance to escape the body gradually. Instead, it forms into gas bubbles in the blood and bodily tissues. These bubbles can block the blood flow, stretch and tear nerves and ligaments, and cause an embolism if the bubbles hit something important like your heart or brain. So imagine a soda can. Shake it up and it gets all bubbly and fizzy inside and will gradually settle back down as long as it's still under pressure. However, open it up after shaking though, and all the pressure and bubbles and fizz gotta go somewhere. Except in the case of a can of soda, that pressure gets released outside the can. In diving, all that shit is thrown throughout your body. Which leads to decompression sickness or the bends. Even in mild cases, this can be so uncomfortable that they make the diver double over in pain, hence the name the bends. And that's the best case scenario. In more severe cases, it is often fatal. To avoid this, divers need to return from deep dives extremely slow. A gradual ascent allows the dissolved nitrogen to emerge from the blood slowly without causing any issues. However, the longer you're down there, or the deeper you go, the longer that time needed to come up slowly increases. Being under such immense pressure for just a few minutes means they need to decompress for at least 10 hours, if not longer. Which is why saturation divers are needed on the drilling rig. They need to be able to keep on diving on an almost daily basis, carrying out regular undersea maintenance work on the drill. Having to decompress for days at a time after each 12 hour shift just is not going to work. After so long at death, your blood cannot absorb any more nitrogen, which is called being at saturation. So if the divers can just stay at the same pressure the entire time they can keep on working for up to weeks at a time without having to spend any more time in a decompression chamber. Two days or two weeks at pressure is the same amount of decompression time when the rotation finally ends and can come back up to the surface. On the Bifur Dolphin, they put in a specialized pressurized habitat on the elevated platform containing two chambers for the divers to live in. Divers would go up and down from the depths in a pressurized diving bell. When they weren't working, they spent their time living inside this specially built habitat and lived off meals made for them by the cooks on the rig and delivered to the habitat in specially sealed containers. This allowed them to go back and forth from the surface to the deep depths without having to go through decompression. They lived completely sealed in this closed system when they were not working for the entirety of their contract and then went through over a week in a decompression chamber. Now, I know these guys get paid really well, somewhere between $100,000 and $200,000 a year, but it sounds absolutely depressing, along with risky and completely uncomfortable. You're in isolation for the entire length of the job, which is normally about 28 days, staring at the same three guys day in and day out. The only break from the monotony is when you go on a dive and get to hear a different voice over the radio. And even then, it's just more isolation. Diving so far down that the sun never reaches. The only light is whatever you're carrying, which isn't much help at all when you're that deep, your field of vision narrows from the lack of any other light source. And then when the job is finally done, you have to spend another week in even more isolation as you go through decompression. No, thank you. You guys can keep that job.

The Crew And The 3 AM Return

SPEAKER_00 7:42

On November 5th, 1983, four divers were working on the Biford Dolphin rig along with two dive tenders. There was two British divers, 35-year-old Edward Coward, 38-year-old Roy Lucas, and two Norwegian divers, whose names I'm gonna fuck up, 29-year-old Bjord Burgessen, and 34-year-old Trules Helovic, along with two British dive tenders, William Krayman and Martin Sanders. Lucas and Coward were on their off shift and resting in one chamber of the habitat trying to relax after several days of straight overtime. Bergerson and Helivik had just finished working at the site below. They had been sent down to inspect the valve and had only planned on being down there for around an hour. However, shit just was not going right. After way too many hours down below, they gave it up and headed back home. It was 3 AM and they were ready to get the hell out of there. Bergerson

The Bell Trunk Transfer Procedure

SPEAKER_00 8:47

and Helovick were brought back up in the pressurized diving bell, which the two dive tenders then attached to the habitat via a trunk, kind of like an airlock from some sci-fi space movie, a narrow passageway through which divers move from one pressurized environment to another. The connection is maintained by a series of interlacking hatches, pressure seals, valves, and manual protocols that ensure no gas escapes and no pressure is lost. Now what's supposed to happen is the diving bell gets witched into place and connected to the trunk. The trunk then gets pressurized to the matching pressure of the bell. Then the divers can exit the bell, strip off their gear and reseal the hatch on the bell. Then and only then can they open the hatch on the habitat, enter, and then reseal the hatch behind them. Only once all this is done, the trunk can be safely depressurized and the diving bell can be unclamped and moved away. On this day though, the two Norwegians made it into the trunk, closed the hatch to the diving bell, and got all their dive gear stripped off, and then as was normal procedure, Elvik began closing the door from the habitat to the trunk.

Explosive Decompression And Instant Loss

SPEAKER_00 10:05

However, before he could completely close the internal hatch, one of the diving tenders, mistakenly believing that the internal hatch was already shut, removed the clamp holding the external hatch in place. Which is a catastrophic mistake that ended in sudden explosive decompression. The pressure within the saturation diving chambers was 9 atmospheres. Outside pressure was one, which is a huge and deadly difference. Like soda from a recently shaken can, air exploded from the higher pressure of the chamber. The blast of air smashed the diving bell away from the habitat, killing Kraman instantly. Saunders suffered a broken neck and back when he was struck by the diving bell. He would later go on to make a full recovery and be the only survivor. Three of the divers within the chamber died instantly. The rapid decompression caused the nitrogen to boil out of their blood, their blood vessels burst, their tissue was torn to shreds, their organs were liquefied and expelled from their bodies. Their body fat melted and leaked through the skin. They died in less than a second, never knowing what happened. Helovic suffered the worst fate. He was shutting the hatch as the decompression hit. The sudden rush of air hit the hatch, jamming it partially closed, leaving only a 24-inch crescent-shaped gap. Helovic, who was being torn apart from the inside with a sudden pressure release, was forced through this narrow gap at a high rate of speed. He suffered severe traumatic injuries as he was bent in half backwards. His insides were sucked out of his body before most of it was shoved through the gap, only leaving bits of him behind. Not going to go into too much more detail on the horror show that the deaths became, but autopsy photos are out there. They are rather gruesome. Like something from a horror movie bed. They look almost fake, like that can't possibly be real, but unfortunately, they definitely are. The first to arrive on scene after the accident were horrified at the sight. One of the operators threw up immediately as the others stood in shock. The trunk had turned into a slaughterhouse with body parts and internal organs thrown about and dripping from the smashed walls. This would lead to severe PTSD for everyone involved. Most of them left the offshore industry afterwards, and several said they could no longer handle confined spaces. But Dolphin Drilling just expected them to go back to work right after this like nothing happened. No sort of support or counseling, just a well that sucks. Okay, get back to work, nothing to see here. The

Blame Human Error Or Broken System

SPEAKER_00 13:11

original conclusion by investigators was that the entire accident was caused by human error on the part of the dive tender who opened the clamp. Why he opened the hatch early has never been figured out. Whether it was by order of his supervisor or his own initiative, or because of miscommunication was never fully determined. Saunders was never able to shed any light on it. But given all the noise coming from the rig in the ocean, it's hard to hear anything on the elevated platform. And in the only way they could talk to anyone inside the habitat was through a stupid megaphone attached to the wall. Plus, being tired from being on shift for over 12 hours, the possibility for confusion and miscommunication just kept ramping up. The Norwegian government stuck with this story for years, putting the blame all on the divers and the tenders. But ultimately, no one would end up taking any blame for the accident, especially considering the mechanical issues that would end up coming to light years after the accident. The Biford Dolphins diving system, dating from 1975, was considered nearly obsolete by 1983. It was not equipped with fail-safe hatches, outboard pressure gauges, and an interlocking mechanism, which would have prevented the trunk from being opened while the system was under pressure, something that had been available for at least a year before the accident. They had been mandated for all other oil platforms, but given the age of the Bifer Dolphin, they weren't mandated to get it updated. They were told to do it whenever they got around to it. We all know how much companies love to spend extra money. It wouldn't be until 2006 until the Norwegian government admitted they knew all this at the time. They just conveniently forgot to put it in the report and instead chose to put all the blame on the divers. Even though they knew 100% this whole thing could have been absolutely avoided if they would have mandated and forced Pfeiffer Dolphin to update their systems to the new standard. The new interlocking system would not have allowed the clamp to be released until the trunk was depressurized. And with the warning lights of the new system, the dive tenders would have something to visually verify that all the hatches were properly sealed. Following this, family members of the dead and other North Sea divers formed the North Sea Diving Alliance in 2008. They kept pushing for further investigation and eventually successfully sued the government and won an undisclosed amount. The Bifer Dolphin remained in service and was involved in more accidents, most notably in 2002 when a Norwegian worker was struck in the head and killed. This accident would cause the company to lose a contract that would end up costing them millions of dollars. They would finally eventually shut the rig down and scrap it in 2019.

Safer Standards Robots And The Wrap

SPEAKER_00 16:23

While this type of diving is still very much needed today, not just for drilling but for things like laying and maintaining underwater cables, and other things we take for granted, it is at least a little safer. Not much, but a tiny bit. It remains a dangerous occupation and will stay that way until technology improves more and more, and robots that can handle the pressure of the depths can take the place of human divers. Now, normally I'm not a big fan of robots being used to replace people. I've seen it far too often. Companies cutting out jobs because it's cheaper and more efficient or whatever to use a robot. But in cases like this, with highly dangerous jobs, I'm perfectly okay with it. We are not built to handle the pressure at those depths. It takes too much reliance on technology and everything going just right for it to be safe. And that was the Biford Dolphin diving accident. Thanks for listening. If you like the show, please consider leaving a rating or review on your Apple Joyce. And you can reach out to the show at historiesadisaster at gmail.com with questions, comments, or suggestions. Well as following the show on social media like Facebook, Instagram, TikTok, YouTube, whatever, and share the episode. Your friends will love it. And just remember, while penguins are excellent deep sea divers, with the Emperor Penguin being able to dive down over 1800 feet, they're not so good at using tools. So if you're thinking about enslaving a pack of penguins to do your deep sea diving for you, just don't. They'll just make a mess of things down there, and then they'll eventually revolt when you don't feed them their favorite fish on time. And you don't want a pack of angry penguins armed with welders chasing you around an oil rig. Anyways, chase that dream. Live for today, because tomorrow is never guaranteed. Thanks and goodbye.