Real Survival Stories - Deep Sea Diver: Miracle on the Seabed

Episode Date: February 1, 2024

A commercial diver finds himself cut off from his support team. When a routine shift goes awry, Chris Lemons is left all alone at the bottom of the North Sea, 127 miles off the coast of Scotland. He has mere minutes before his emergency supply of oxygen runs out. His colleagues will risk everything to get him back. It’s up to Chris to stay alive long enough for them to reach him… A Noiser production, written by Joe Viner. For ad-free listening, bonus material and early access to new episodes, join Noiser+. Click the Noiser+ banner to get started. Or, if you’re on Spotify or Android, go to noiser.com/subscriptions If you have an amazing survival story of your own that you’d like to put forward for the show, let us know. Drop us an email at [e-mail] Learn more about your ad choices. Visit podcastchoices.com/adchoices

You're a podcast listener, and this is a podcast ad heard only in Canada. Reach great Canadian listeners like yourself with podcast advertising from Libsyn Ads. Choose from hundreds of top podcasts offering host endorsements or run a pre-produced ad like this one across thousands of shows to reach your target audience with Libsyn Ads. Email bob at libsyn.com to learn more. That's B-O-B at L-I-b-s-y-n dot com. It's 10.15pm on September the 18th, 2012. 127 miles off the east coast of Scotland, the North Sea rolls under gale force winds.

Large swells break into frothing white peaks. The driving rain almost drowns the lights of the Bibby Topaz, a diving support vessel as it lists from side to side. But 100 meters below the surface, on the seabed, there is deathly calm. Through his diving mask, 32-year-old Chris Lemons scans the black expanse above him, his panicked eyes searching the gloom for a glimmer of light. I remember taking a pause, I think, almost a pause of disbelief when I did land on my back, looking up into the sea above me. I often call it the sky above me, but it's definitely the sea above me, the blackness,

and almost a surreal pause, just thinking, you know, where am I? What am I doing? Against the total silence of the sea, the thud of his heart and the blood roaring in his ears is almost deafening. Gradually, the reality of what's happening starts to sink in. Where he is, how he got here, and the urgent steps he needs to take if he's going to survive. Short of breath, Chris draws a lungful of air from the emergency gas bottles on his back, allowing him to think. His crewmates up on the surface, there is only hope. But finding him down here, in the pitch black, all but impossible. Quite literally, a shot in the dark. All Chris can do is improve his chances of being

spotted. Somewhere nearby is the steel structure he was sent down here to work on. It's big and yellow, the size of a two-story house. And yet, it is nowhere to be seen. You can often get disorientated down on the seabed. It's very easy to get lost, to wander off in the wrong direction at the best of the times with somebody giving you instruction with a compass, all the rest of it. But I could see nothing at all. I did not have a clue which direction I needed to walk in. Chris has no choice but to pick a direction

and hope for the best. He moves slowly forward, arms outstretched, praying he'll bump into something solid. In his cumbersome diving suit and heavy boots, it's like wading through treacle. He takes another deep lungful of air,

which is when a sudden, terrifying thought takes hold. leading through treacle. He takes another deep lungful of air, which is when a sudden, terrifying thought takes hold. His emergency gas supply is limited. He probably has only about six minutes left. Six minutes until he draws his final breath. Ever wondered what you would do when disaster strikes? If your life depended on your next decision, could you make the right choice? Welcome to Real Survival Stories. These are the astonishing tales of ordinary people thrown into extraordinary situations. People suddenly forced to fight for their lives. In this episode, we meet Chris Lemons.

He's a commercial diver working on oil rigs off the Scottish mainland. It's his job to carry out maintenance deep below the surface. This far underwater, even the slightest mishap can have dire consequences. So when an accident leaves Chris cut off from his support team, the pressure is extreme in more ways than one. I was definitely thinking a lot about whether am I going to get out of this? Yeah, and the truth is no. I think I never really, I think I decided very quickly that I wasn't, I wasn't going to get out of this. But he may be alone he's not been abandoned as time ticks away his friends and colleagues will risk everything to get him back it's John Hopkins from Noisa. This is Real Survival Stories. It's 7.55pm on September 18, 2012, 127 miles off the coast of Aberdeen, Scotland.

It's a typical Tuesday night on board the Bibby Topaz, a dive support vessel stationed in the North Sea's Huntingdon oilfield. Large waves crash against the boat's steel hull, which rises and falls with the 18-foot swell. The weather is rough, but nothing out of the ordinary for this time of year. And besides, down in the bowels of the ship, 32-year-old Chris Lemon's thoughts are already below the surface, on the seabed, where he's about to begin his night shift. In terms of deep-sea saturation diving, Chris is still a rookie. But this job is something he's worked hard for, and he's proud of it. It's another aspect of his life that has come together of late. I think life is a lot easier when you know what you want to do. I always feel sorry for any youngsters who are a little bit

unsure because you can drift, can't you? And I was perhaps drifting, and that gave me sort of a clarity of purpose for my life. I was still very much in the infancy of that portion of my career so it was still exciting and fresh and I was still very much learning and and trying to prove myself so yeah I was I guess at a stage in my life when it was the start of lots of things I was engaged at that time and getting ready to get married in April of the following year so yeah transitional state of my life I guess you know, the start of a new phase and that kind of thing and start of settling down and growing up, I guess. For years, Chris observed saturation divers up close when he worked as a deckhand on support vessels like the Bibitopas. He always marveled

at the mysterious masked men going about their lives in isolation, risking their necks on the sea floor. Self-sufficient, unflappable, the ultimate professionals. They're also very well paid. I think it probably turned up on the key sides in nicer cars than I had as well, which probably, I won't say that wasn't a factor. I'm going to make it sound far more romantic than it is because I know better now. But at the time, they seemed like enigmas really because it's a strange world because they live in these sort of pressurized capitals for a month at a time. So they're on the ship, but you don't really see them. You might see them in passing when they come aboard and then they're sort of lost to you.

It all looked very exciting. And I think from that moment on, that sort of lit the touch paper, really. It was a seminal moment for me, really, in my life, because it meant that I had direction all of a sudden, which I didn't really have till then. You know, I suddenly thought, well, I want to do that. Now, 18 months on from his long-awaited promotion, Chris sits on the small bunk in his own pressurized capsule. He awaits his taxi ride down to the seabed. In truth, he's still not gotten used to being sealed off in a tin can, cut off from the world for weeks at a time. It's such an incredibly alien environment to have the door of the chamber shut on you on day one and be pressurized down and know that there's no escape.

You are in there now for a month and pretty much nothing is going to mean you're coming out. If your mother dies or if your appendix bursts, you're still looking at several days of decompression to come out of the chamber. Isolation is one of the hardest aspects of the job, but it's also an absolute necessity. His life depends upon it. When the human body descends to extreme depths,

the water pressure compresses the air within the lungs. This can lead to severe internal trauma. So, before diving, the diver's body must be pressurized to match the pressure of the seabed, an acclimatization procedure known as saturation. This allows them to work safely at depths of up to a thousand feet. Later, at the end of the shift, a diver cannot simply return to normal atmospheric conditions at sea level. If they did, the compressed gases in their body would suddenly expand into toxic air bubbles, a potentially deadly phenomenon known as the bends.

Instead, they must go through gradual decompression, a process that can take up to five days. Unsurprisingly, the psychological strain of all this can be significant. It's intimidating, yeah, and like a lot of people, you suddenly find yourself in that place, or I do anyway, you find yourself in that place very much wondering what on earth you're doing and do you belong and are you good enough. Yeah, I mean, even probably to the day I stopped physically diving, wondering what on earth you're doing and do you belong and are you are you good enough and yeah i mean even probably to the day i i stopped physically diving i probably still felt like i had

you know imposter syndrome or whatever they call it you know you really do think you're sort of pulling the wool over people's eyes by being in there at all i guess you know luckily chris isn't entirely on his Dive teams usually work in teams of three. On this particular rotation, he's alongside two older, more experienced guys, Dave Uasa and Duncan Alcock. Theirs is a brotherly bond, forged at depth. They may be monitored and supported by over 100 support crew aboard the Bibitopas, but once they go underwater, they'll be relying on each other. reach great Canadian listeners like yourself with podcast advertising from Libsyn Ads.

Choose from hundreds of top podcasts offering host endorsements or run a pre-produced ad like this one across thousands of shows to reach your target audience with Libsyn Ads. Email bob at libsyn.com to learn more. That's B-O-B at L-I-B-S-Y-N dot com. It's 8pm. Amidst the dials and valves

of the saturation chamber, Chris, Dave and Duncan carry out their final checks before they taxi down. Then they crawl from the main pressurized chamber into the diving bell, the submersible vehicle that will carry them to their working depth.

Tonight, their task is to carry out repairs on a drilling template known as a manifold, a large metal structure on the seabed. Chris is diver number two. Dave is diver number one. Duncan will remain in the diving bell, overseeing their progress. They give the signal to Craig, their supervisor on the bibi topaz. They're ready. The bell drops to a depth of 80 meters. Then it comes to a stop. Chris and Dave zip themselves into their diving suits.

Next, they ensure they're securely connected to the bell by their umbilicals. These cables will provide them with air, light, and communication, both with the bell and the boat. Furthermore, without the warm water pumped down the cables and around their suits, the divers would soon become hypothermic in the near-freezing conditions. Umbilical is the right word. It's all our sort of keepers of life, really. We get an essentially infinite supply of breathing gas fed to us. We get electrical power to power a light and a camera on our helmets down to us.

And we also get this hot water that I described pumped down to us as well. Chris and Dave exit via a hatch, slipping out of the bell and into the dark, frigid water of the North Sea. No matter how many times they do it, it's always a bizarre moment, like an astronaut stepping into the vacuum of space. There are stories of people even going on their first ever bell run, having spent years building up to it, going down in the diving bell, opening the bottom door, getting out onto the little stage below, or even opening the bottom door, looking into the water and saying,

I can't do this, people with years of experience. So it's an unknown, I guess, as well. I don't think you really know how you're going to react to that sort of place, if you like, until you face it. Guided by the beams of their head torches, Chris and Dave drop a further 20 metres. Gradually, the yellow steel tubes and struts emerge from the gloom. Their boots land with an echoing clang on the metal structure. Voices crackle through the radio earpieces inside their helmets, instructions coming down from Craig.

Chris and Dave copy. They take out their tools and begin their work. For them, it's just another day at the office. The only perhaps differential was the weather above us was a little bit rough. I think it was blowing something like 35 knots of wind and the sea was about three or four meters, I think. So it was quite stormy. At the end of the day, it's the North Sea and it's quite rare that it's flat calm. So you

have to have a vessel and the equipment to be able to dive in that weather or else you'd never get anything done. Fortunately, the Bibby Topaz is equipped with something called a dynamic positioning system. This should keep the boat fixed in place directly above the divers, whatever the weather. Despite the physical distance between them above the divers, whatever the weather. Despite the physical distance between them and the vessel, 100 meters and 100,000 tons of seawater, Chris and Dave are kept company by the constant background radio chatter as well as the reassuring voice of Duncan in the diving pal. So after about an hour and a half,

when an alarm sounds through Chris's earpiece, he's not overly concerned. You can hear everything going on in the background normally, which is usually people giving divers a bit of a roasting normally, how much better they did it in their day, that kind of thing. But what we also hear sometimes are alarms, oxygen alarms, carbon dioxide alarms, hot water alarms, and they do go dioxide alarms, hot water alarms, and they do go off pretty regularly for one reason or another. It's never a big deal.

We hear them all day every day. These were a little bit louder, but I don't remember being panicked by them to any extent. So that was our first inkling something was going on, but I didn't really do much more than raise an eyebrow. Chris continues working but then he hears Craig on the airwaves telling him to stop. He said to us to put everything down put all your tools down get yourself out of the structure pretty calmly but there was just something about the tone of his voice which told us this wasn't a drill that was for for sure. I don't think I had any explicit understanding

of what was happening above us. He didn't communicate that to us, didn't need to particularly. He just told us to get out. Chris and Dave drop their tools and start climbing up the manifold. Moving by torchlight through the lattice of pipework, they follow their umbilicals like guide ropes. In his ear, Chris can hear his supervisor's repeated instructions.

More urgent now, to get back to the bell. But as they near the top of the manifold, there is a surprise in store. I think probably the first inclination we had that something unusual was going on was when we got out of the structure and looked up to where we'd left the diving bell, if you like, straight in front of us with our umbilicals nice and straight back to it, and it wasn't there. Their lines stretch out above them before bending over the topmost edge of the manifold, but the bell is nowhere to be seen. Chris feels a twinge of panic.

They're in uncharted waters now, But the instruction from above is the same. Follow the umbilicals. They continue climbing, hand over hand. Dave is up ahead. Chris lags behind. He has to keep turning to gather up the loose slack of his line. It's trailing behind him. So I know that having had to use both hands to climb,

I've left a loop of umbilical behind me, really. So there's sort of a U-shape hanging down the side of the structure. So I've turned to clear that, to pull it, to make sure that it doesn't catch on anything. But then he realizes it's snagged. It's caught on a piece of metal machinery jutting out from the structure. He tries to yank it clear, but it won't budge. And then he feels the cable being pulled from above him.

It goes taut, and the loop below starts to close around the machinery like someone tying a knot. So, absolutely no doubt, that was the point. I knew instantly that I was in trouble. It's 10.15pm. Up on the surface, the Bibi Topaz lurches over the rolling sea. She drifts 10 metres, 20 meters, 30. This shouldn't be happening. The computer-controlled positioning system has failed catastrophically.

The crew try frantically to reverse the calamity. Back down below, with every inch the topaz drifts away, the knot around the manifold tightens and the strain on Chris's umbilical increases. All of a sudden I'm an anchor effectively on the bottom of an 8,000 tonne vessel. You know, it's me attached to something with a vessel moving away in an uncontrolled fashion and I could sense that the umbilical was tightening already so that's the point at which panic starts to set in. Chris scrambles back down to where the cable is caught. He tries to work his gloved fingers into the crack between it and the metal tubing trying to pry it loose but it's impossible.

He's in a tug of war with 8,000 tons of steel and gale force winds. Dragged by the ship, the umbilical is being forced through a tiny gap between two pipes and Chris is being pulled straight towards it. So as it's being dragged down through what was basically a two inch gap, I'm being dragged down towards that. I remember my legs were sort of splayed over. There's a tubular section of the structure. My legs were being splayed either side of it and I was being sucked down into it.

I remember thinking, at some point here, my legs are going to snap here at some point. And that's obviously, that was my first concern. I remember my second concern being if that umbilical keeps slipping towards that gap, I'm going to go through that gap as well. And it's two inches wide and that's going to be like being pulled through a cheese grater. It's not going to be a nice way to go either. So these are all obviously frightening things to deal with. Chris radios Duncan, begging him to feed him more slack so that he can free the snagged cable. He can hear the fear in his own voice, the desperation.

At a certain point after my umbilical has become trapped, they begin to realize that they can't pull mine in and that I can't, and I'm asking them to give me some slack and Duncan in the bell, because there's suddenly very enormous tension on the umbilical between me and him. They're sort of looped on a rack in the diving bell and it's so tight that he can't get loops off to give me slack, to allow me to free myself. Duncan's powerless to help him. With each passing second, the tension in the umbilical grows. And suddenly, Chris becomes aware of a dim light cutting through the darkness, weaving towards him. It's Dave. Come back to help. Ten meters, five meters. He's just two meters away now. But then he stops. Our umbilicals are 50 meters long, or they were

that night. So that means you can only get 50 meters away from the diving bell. So Dave sort of comes to get to me, but he realizes that he can only get to within a couple of meters of me. He'd got to the extent of his umbilical with the vessel moving away from our position. So we have this sort of almost cinematic moment really, where I can remember because of the nature of a diving helmet, you can only really see people's eyes. And we had a bit of an eye to eye moment where I think I'm entreating him to come and help me. And he's looking at me and sort of saying, you know, sorry, pal, you're on your own here. I can't do anything. The two divers stretch out their gloved fingers,

but it's no use. Slowly, the distance between them increases. Dave's being pulled away. All Chris can do is stare in dismay as his rescuer is dragged backwards and disappears once more into the gloom. He's pulled away from me as the diving vessel continues to move away and first I see him being pulled away and then I sort of lose sight of him but I can still see his light being pulled away and then I lose sight of his light. Ultimately he's pulled off the structure himself by the vessel

and he has no option at that point other than to turn and head for home really. There's nothing he can do for me because he can't reach me. Chris is on his own once again and still inching towards a painful death. But then the umbilical stops moving. With just a few feet left to go to the two-inch gap, Chris stops where he is. But it's only a moment's reprieve. The umbilical has become wedged. The knot is now closed. And with the strain still increasing, something has to give. Chris hears a terrible, terrifying creak of the metal flexing under pressure. Then a low, ominous groan, drifting down from above as the cable stretches to breaking point.

I can just feel it tightening and tightening eventually the tension becomes too much and dave describes it as like a shotgun going off you know an enormous bag very quickly after that the umbilical snaps and parts and i find myself suddenly with attention released and i just fall backwards i've been pulled into the side of the structure so i just fall backwards like a an upturned turtle down to the seabed Chris lands with a muffled thud at the bottom of the North Sea He stares up into the yawning void It's completely quiet Save for the soft hiss of his emergency gas tank.

With his umbilical broken, his air supply is now limited to what he carries in the bailout bottles on his back. Maybe seven or eight minutes worth. Maybe less. He's also lost all means of communicating with Duncan and Craig, not to mention the power for his head torch. He is entirely alone in darkness and silence. It took me a couple of seconds to orientate myself, but once I had, I don't remember having too many thoughts about the bigger picture in terms of what was happening above me. I wasn't

seeking an explanation at that point. Really just all we were thinking about then is surviving really. And my only thoughts are I need to get back to that diving bell. I need to get back to that breathable environment as quickly as I possibly can. Chris gets to his feet. He knows that whatever is going on up on the surface, the crew will be doing everything in their power to rescue him. But they'll have to find him first. It was more dark than I'd ever seen before. Absolutely, I guess, no ambient light from the bell, no light from my hat light, to the point where I couldn't even see the shadow of my hand in front of my face.

You know, absolutely pitch, pitch, pitch, pitch black. To have any chance of being spotted, Chris needs to get back on top of the manifold structure. It'll be the first place they'll look for him. Once again, he'll have to climb. But this time, there's no line to guide him. And in the dark, he doesn't even know which direction to walk in. The odds were against me, really, that I would walk in the right direction. I could have easily walked out into what was effectively

no man's land, really, which certainly would have rendered finding me a lot more difficult and rescuing me as well because they would have had to lower the diving bell into a dangerous position to get down to me. Chris takes a deep lungful of air from his emergency supply. How much does he have left? Six minutes? Five? There's no time to dwell on it, but nor can he afford to go the wrong way.

His life depends on this decision. Right or left? Forwards or backwards? He angles his body in what he hopes is the right direction and sets off walking. He takes one step, then another, arms outstretched, fumbling in the darkness. He feels nothing. But then... Very lucky, really. I took a couple of steps and bumped into what I assumed was the structure. I But then... And I'm panicking at this point. There's no doubt. I'm breathing hard. I remember being desperately frightened that now I'd found it, that I would lose it. So I was clinging to it with both my hands on my feet,

trying to find a way to climb up it, edging along the side of it, running my boot down the bottom to make sure I didn't lose it. I remember really being fearful of losing that because you could take two steps away from it and not find it again very, very easily. So disorientating you know complete blackness chris inches his way up the side of the structure but as the exertion increases so does his breathing sips become gulps as he drives with his arms and legs, heaving himself higher.

Finally, he reaches the top and crawls onto the flat mesh platform. He looks up, scanning for the lights of the diving bell. I looked up, fully expecting to see the diving bell somewhere above me, the lights of it, fully expecting to see Dave heading back to get me. And I remember getting to the top and looking up and seeing nothing but absolute blackness, you know, not a speck of light above me. That being a seminal moment, really, where I moved into, I thought,

you know, I remember thinking, this is life-threatening now, you know. Mortal fear courses through him now. He tries his best to think clearly, to lay out the facts of his situation and reach a rational conclusion. I didn't do the maths exactly, but I knew I probably only had seven, eight, nine minutes of gas available.

I'd probably use three, four, five of it getting back up to the top of the structure, so I knew there can't have been that much left. And even if they would have been there to pull me back, the margins between getting my head back into a breathable environment before I ran out of breathing gas were going to be slim. But to have nobody there and nothing, I realized fairly quickly then that chances of survival were going to be slim, if not non-existence really. So that was definitely a moment, I think, when things changed.

It is almost 10.30pm, over 10 minutes since Chris's umbilical snapped. He lies in the fetal position on top of the manifold structure. Each rattling breath brings him closer to the end. Oddly enough, despite the four degree seawater, he doesn't feel cold. It's as if his brain has decided not to feed this information to his body. One small mercy. A transition definitely from a place of fear and panic, I suppose, to I remember that just subsiding, strangely just subsiding and almost being washed over with grief at that point, really. Yeah, moved into a place where I had almost accepted what was coming and just being

very immensely sad, you know, really, really sad and confused and angry and bewildered that I was, you know, what I thought was about to die in this strange, ethereal, dark, lonely place. I think for anybody, they turn to the people at home, the devastation you're about to cause. I remember sort of mulling over the moments when my parents were going to be told, as I described earlier, I was about to get married,

so, you know, the thoughts of my fiancée, the news being broken to her, the devastation that you're going to cause to everybody, you know, at home that you're lucky enough to have love you, really. Chris uses up a few more seconds of oxygen to cry out for help. He calls Duncan's name, pleading with his colleague to drop down out of the darkness and save him. But he knows that nobody's coming, at least not in time to rescue him.

He's down to his last few seconds of air now. I remember being scared that the moments of dying were going to be painful. I remember worrying that maybe my hat would flood up with water. I didn't really want to drown. I didn't really want that to be the way I went. I didn't want it to be a painful process. I think the actual thoughts of death itself, I don't remember being particularly frightened of that, if that makes sense.

I remember being frightened or worried about the consequences for other people. I was surprised I was still breathing at one stage, but eventually I remember the breathing getting tight on the bailouts or the emergency supply of gas. So I think I knew at that point that the end was imminent. I'm sure there'll be people in the audience who are perhaps scuba divers and they've had the misfortune of breathing down a bottle. So you kind of know when it's coming, it suddenly gets a bit harder to suck the gas down if you like. I remember thinking, this is it, I hope it doesn't hurt.

I think it's how I've normally described it. And that's very true. It was just pretty matter of fact at the end. 10.40pm At the bottom of the North Sea, nothing stares. Chris's motionless body lies crumpled on top of the steel structure. And then slowly, out of nowhere, comes a faint flicker of light.

A torch beam, trickling down through the greenish murk. The light gets brighter as it descends lower and lower. Eventually its source takes shape. A lone figure. There is a dull thud of boots landing on metal and the rattle of a respirator. Arms reach down to scoop up Chris before carrying him up back towards the surface. So in terms of my own memories, I have very vague recollections. I'm sort of put up into the diving bell.

Duncan takes my helmet off, gives me the kiss of life. I've got some recollection of flashing lights, of flashed images. I've got vague sort of snapshots of things on the way back. I've got a vague snapshot of seeing Dave crumpled in the corner of theed images. I've got vague snapshots of things on the way back. I've got a vague snapshot of seeing Dave crumpled in the corner of the diving bell. I reach out and I grab Duncan's hand and Dave's hand and give them both a squeeze. I obviously knew something had happened. So yeah, vague memories of that. It was a progressive return to consciousness, I suppose. Chris is blue from lack of oxygen, but he is awake, and by some miracle, he is breathing. The next thing he knows is 40 minutes later, and he's back in the saturation chamber,

on board the boat. He stares up at his colleagues. None of them can believe what they're seeing. After just six minutes, oxygen deprivation can lead to irreversible brain damage. After ten, death is the only plausible outcome. Chris was without air for over 20 minutes, maybe longer. Yet somehow, he's sitting up and talking. Ultimately, I was fine.

As I warmed, I regained and I was chatting away pretty quickly. So it was really resuscitative cups of tea, I think, or restive cups of tea, which was the main medicine I need because fundamentally I was fine. And I think it was obvious to them quite quickly that I was fine. As they sit there below deck, Chris learns of the dramatic series of events that led to his rescue. After the crew of the BB Topaz failed to get the positioning system back online, they had to manually navigate the ship back to its original position. Meanwhile, they deployed a remote submersible to look for him. At 10.32pm, 21 minutes after the initial alarm sounded, the sub located Chris on top of the manifold. With the live stream being fed to screens on the vessel, his colleagues watched

on as their unconscious friend twitched and spasmed, probably a result of toxic levels of CO2 building in his blood. Assuming he was dead, Dave was sent down to retrieve the body and bring it up to the diving bell. This in itself was a monumental feat of athleticism and courage. But then once back inside the bell, Duncan had realised that Chris was still alive. He managed to resuscitate him using CPR. Truth is, if there's a hero in this story, it's definitely not me. It's absolutely the boys who came to get me and persisted and saved my life ultimately. So if anybody should be getting applauded. It's absolutely them.

In total, Chris was on the seabed for approximately 35 minutes, with no more than eight minutes of gas in his tank. Medical experts have since debated the factors that contributed to his survival. One theory is that the frigid seawater forced his body to effectively go into hibernation, dramatically slowing his metabolism and circulation to allow his heart to beat slower. Another is that the pressurized gas Chris was breathing, a combination of oxygen and helium known as heliox, delivers far more oxygen to the blood than air above sea level.

And that the particular batch in Chris's backup tanks was even more oxygen rich than normal. Ultimately, it was the gas that we breathe that was the saviour. We breathe these gas mixes with elevated contents of oxygen and that when you mix that with the miracle really that is pressure and that oxygen is pressurised into the tissues of your and ultimately to the cells of your body and hyper oxygenates everything so i think that's what's my fairly certain that's that's what saved me ultimately one thing i have learned you know i've talked down at the british medical society in places like that is that the margins between having been okay and not having brain damage and and anything worse than that would have been

massively massively small they all still think i was unbelievably lucky to come out unscathed considering the physics and the physiology and the gases involved. In the coming months and years, back on dry land, Chris goes on to get married and have two children. He continues to work in the commercial diving industry though as a supervisor now not a diver he's more than happy to take a back seat i would say i've got maybe a more acute awareness of death i would say that's the only thing that's really changing me fundamentally i maybe think about death a little bit more i'm not going to say i'm less frightened of it but i think i'm maybe more comfortable with how that's going to be when it comes and more at peace with how that

might happen. But in terms of my day-to-day outlook, I think I still try and make the best of every day because I have a consciousness that life is finite. Maybe that comes with that more acute awareness of death, more that it can so abruptly be ended for any of us at any point. So you may as well just get on and enjoy what you do have. In the next episode, we meet Lauren Elder. In 1976, she's 29 years old, an artist based in San Francisco. When she takes up the last-minute offer of a sightseeing flight, she never imagines she'll end up stranded on a mountaintop. As night falls and the temperature drops, Lauren will face a desperate choice.

Wait for a rescue that might never come, or strike out for help alone. That's next time on Real Survival Stories.