On 18 September 2012, disaster struck for diver Chris Lemons whilst completing a job at the bottom of the North Sea, 204km (127 miles) east of Aberdeen. Chris had only been 18 months into his career as a saturation diver when he was assigned to perform work on an oil structure with experienced divers Duncan Allcock and Dave Yuasa, attached to the Bibby Topaz support vessel. Due to a fault, his umbilical cable fatally snapped and Chris was left unconscious on the seabed for almost 30 minutes with no oxygen or hope for survival. Thanks to his quick reactions and the heroic efforts of his crew, Chris miraculously survived and continues to dive today.
Chris recalls, “It was 10pm at night, we were diving like any normal day at the office really. We were working on a manifold called the “Huntington Manifold,” which had a series of wells inside. We were replacing an area of pipework and doing some pressure testing. It was myself and my colleague Dave Yuasa in the water and Duncan Allcock who was the Bellman that day.” (The bellman is the standby diver, and may have to recover a distressed diver to the bell and give first aid if necessary and possible.)
“We had only been diving for about an hour. We were inside the structure, working away with no problems or indications of what was to come. The first indication we had of anything was that we had a constant line of communication between us and our diving providers through our helmets and then we heard the alarm sounding in the background. That is not unusual in itself, as sometimes they can be carrying out testing, so you can hear them anyway. However, he then informed us in a stern voice to get out of the structure and back to the bell. You could tell from the tone of his voice and the urgency, that it was not routine. You could tell it was something serious and something we had to act on right away. We made our way off of the structure that we were working on as quickly as possible.”
“When we got out, we were expecting to see the bell in the water, but because the boat had a catastrophic failure of the dynamic positioning (DP) system, it had lost position and gone back behind and over our heads. Our umbilicals were trailing on top of the manifold, so we started to climb them to get ourselves back to safety and back to the bell. Dave was climbing his and Duncan was pulling his in, but because Dave could only pull one umbilical at a time as I climbed, I fatally left one loop of umbilical behind me. When I got to the top, I turned around to check that it was all safe and taken care of but literally in a heartbeat, I found that it had caught on a transponder bucket with a metal outcrop on the side of the structure. This should have actually been removed when they installed it, but it had been left in place and my umbilical had become caught underneath it. It happened so quickly that it become extremely tight, to the point that I couldn’t move it. It was at that point that I realised I was in serious trouble as it was completely immovable.”
“The first thing I realised was that I’d been sucked in towards it with the boat stretching my umbilical. The boat was pulling me in towards it and my legs started to splay, I thought they were going to end up snapping. It was jammed fast and at that point Dave realised that something was wrong. He turned and tried desperately to get back towards me, arms flailing and we had this little moment where we were eyeball to eyeball looking in each other’s eyes, before he was pulled backwards in to the darkness. Dave describes it like being in a film, which is exactly what it was like. He had this light on the top of his helmet and he was getting pulled back in to the darkness and we never saw each other again until it was all over…”
“A couple of seconds after that, I lost the supply of gas to my helmet. The umbilical had stretched to such a point, that the hose that brings the gas down had kinked and I lost my supply of gas. I turned on the bailout supply, through the knob on the side of the helmet, which released the supply of gas we keep on our back for an emergency. That was pretty panic inducing, as you never expect to ever have to use that”
“Shortly after, the communications cable was stretched to a point where it stopped functioning. The people I could hear in my earpiece crackled and disappeared, not long after that the whole umbilical snapped. It literally went off like a shotgun and instantly I was in darkness... my light went off and I tumbled towards the seabed.”
“Looking back, I wasn’t really sure what had happened but I knew my best chance of safety was getting back on top of the structure and to try to get myself back on the diving bell. I stumbled around in the darkness for a while and was very lucky to bump in to the structure, because I was completely disorientated. There’s no way of knowing which way is which and I could have very easily wandered in to the nothingness or “No man’s land” which would have made finding me very difficult.
Bumping in to the structure, I found an old hose that we had been using to climb up and pulled myself to the top, expecting to see the diving bell up there and people coming towards me.
I quickly realised there was nothing, not a speck of light in the sea above me.”
“That was a strange moment, as I did a quick calculation of how much gas I would have left. At that depth the bailout probably gives you around 5-6 minutes of gas and I’d already used about 2-3 minutes of this getting myself back up on the structure. Therefore, with no imminent signs of rescue or nowhere to go, you realise your chances of survival are pretty much zero.”
“When you first get stuck, panic seeps through you and you’re scared, desperately trying to get yourself to safety. But when I got to the top of the structure and it dawned on me that the chances of me getting out of there were non-existent, a sort of a calmness comes over you, a resignation. I remember feeling very sad and a great deal of disbelief at how I had ended up in this position. It seems like a very strange and lonely place to end your days. You think of the people at home and the damage you’re going to do to the ones who love you, from the realisation that you are not coming home. It’s more of a sad feeling than a scary feeling.”
“Eventually, the crew conducted what is called a “Hard reset”, which is effectively turning the DP system on and off. This happened nearly 30 minutes later and they struggled to get control of the boat. They did, however, manage to execute it successfully and this brought the boat back around and Dave came down to fetch me. By this point, I’d been unconscious for around 30 minutes or so.
Unfortunately, there was over 100 people on the ship watching this through live screens because the remotely operated vehicle had managed to get to me not long after I fell unconscious. The crew had 30 long minutes of watching a twitching, then non-twitching body which must have been traumatic for them.”
“Dave came down and put in a super-human effort to drag me back to the bell. He is a really fit guy and even he struggled pulling the weight of my body back to the bell. Dave did a remarkable thing there and popped my head back in to the diving bell.”
“Duncan who was in there too, ripped my helmet off and gave me two breaths and amazingly, I came round almost immediately. I gasped then essentially came back to life. It’s amazing to me that I not only survived, but survived without any obvious signs of brain damage, as oxygen deprivation can kick in pretty quickly.”
“After we got back we had to decompress, so we had 4 days in the chamber. We all came out and had to have full medicals and cognitive tests and there was an investigation in to the cause of what happened.”
“Once they had completed the investigation, we were given the option to go back and after some discussion, we all decided as a team that we would. It was like getting back on a bike, we thought if we didn’t do it then, perhaps we never would.”
“A little nervous laughter, then 3 weeks later we went back to the same place and finished the job. Once we were back in the water it was almost all forgotten and we carried on as normal.”
“As a team, we learned a lot of practical things from the incident, in terms of the mechanics of getting someone back to the bail and we implemented changes to lots of little protocols on the boat as well. We also introduced the COBRA breathing apparatus. This is a rebreather, which provides you with a higher volume of gas in an emergency, so instead of 5 minutes you would now have 40 minutes in that situation.”
“Ultimately, my survival is a testament to the unbelievable work and quick thinking of my crew on that day. It was a single point failure that could never really have been predicted and how the crew, and everybody on board the Topaz that night, reacted was a success story really. How we managed to get ourselves out of that situation without anyone dying is incredible and I will be eternally grateful to them. We learned a lot that night and we are stronger people for it.”