The Last Breath: how diver Chris Lemons survived without oxygen for 30 minutes on the seabed It’s a mystery how he stayed alive for so long – but he came to with a ‘groggy, drunken feeling’

Seven years ago, Chris Lemons, then 33, was at an exciting time in his life. He was engaged to Morag, building a house in Scotland and 18 months into his work as a commercial saturation diver in the offshore oil and gas industry.

This was not a profession that Chris, who was born in Edinburgh and grew up in Cambridge, had longed for all his life. He originally fell into deckhand work, but was intrigued by those divers who spent months at a time in a pressurised chamber on the ships on which he worked. This technique enables divers to acclimatise to working under hydrostatic pressure, to reduce the risk of decompression sickness (the bends) when they work at great depths for long periods of time

They were like an enigma, but one that inspired him to try it.

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No matter what happens, you’re stuck

Adjusting to life in a chamber with 12 other people was strange, intimidating and frightening for Chris. No matter what happens in what is essentially a decompression tank – if you break your leg, your appendix bursts or your mother dies – you still have to face four to five days’ decompression. There’s no shortcut. There’s also no privacy. CCTV cameras are on 24/7, even in the loo and shower.

Footage of this kicks off Last Breath, a film that tells the story of a day in the life of three saturation divers – on 18 September 2012.

It was a straightforward job at the bottom of the North Sea, 204km (127 miles) east of Aberdeen: Chris had been assigned to work with his mentor Duncan Allcock and a very experienced diver, Dave Yuasa. Duncan was manning the diving bell, which was attached to the Bibby Topaz support vessel on the surface, while Dave and Chris dived down to perform maintenance work on an oil well structure.

Drifting into danger

The water and weather appeared calm, in North Sea terms anyway (where it’s always pretty rough). But what they didn’t know was that 100m above them, a 35-knot wind and a 5m swell were hitting Bibby. Its normally reliable dynamic positioning (DP) device, which keeps the ship locked in place, had shut down and its backups had failed. The emergency status was on red. The ship was drifting off course.

Down below an alarm went off and Dave and Chris were instructed to return to the bell at once. Both had “umbilical cords” attached to the bell – these are thick twists of cables that deliver the requisite helium and oxygen mix the divers need to breathe, hot water to keep them warm, and light and communication with the support team.

The pair scrambled back up. But Chris’s cord got caught on a metal outcrop, which wasn’t meant to be there. Then the ship on the surface moved and the cord tightened. Dave returned to help but was dragged, flailing, back to the bell as he heard Chris’s cord rip.

‘There was nothing I could do’

Duncan was trying desperately to drag Chris’s cord back in, but it had tightened so much that it was bending the metal frame out from inside the bell. “I was shitting myself,” he recalls. There was nothing he could do.

“I could hear his umbilical cracking,” Dave continues. “It’s the noise that something makes before it breaks.” There was a bang as Chris was sent tumbling back into the darkness.

This is where Chris takes over the story. “It was complete and utter darkness, where you can’t see a single thing,” he remembers. “Not a speck of light, not even enough to read my gauge to see how much oxygen I had. I was completely disorientated and didn’t know which direction the structure was in.

Fortunately, it was a couple of steps away and he was able to climb it. “I remember clinging on for dear life because I couldn’t tell where the edge was and didn’t want to fall off. Then desperately looked up for any sign of the bell.”

‘I was going to die in a strange, alien environment’

He knew he only had about five or six minutes of gas left, and almost no chance of rescue. “I had a strange mix of emotions. I was very sad, but mostly disappointed and guilty for the ones I was leaving behind, especially Morag. I pictured her being told and was upset. At the same time, I was screaming out for Duncan to come and rescue me. There was also disbelief that I was going to die in such a strange, alien environment.”

His breathing got harder and tighter and he hoped death wouldn’t hurt. Then… nothing. Around 30 minutes later, the remotely operated underwater vehicle (ROV) with a camera on top appeared. The DP had been fixed and Bibby was back in place.

Surviving the impossible

How Chris survived that long without breathing is a mystery. One theory posited by experts is selective brain cooling, which suggests that when you’re immersed in cold water for a long period your body carries out processes that allow cooled blood to enter the brain. Chris himself believes that because the bailout cylinder he had been breathing from had a much higher proportion of oxygen, his tissue was saturated with more oxygen.

In the film, the footage of Chris’s body lying there twitching is an awful sight. For those on the ship, seeing it through the ROV images was horrendous.

It was the film’s directors, Alex Parkinson and Richard da Costa, who made the decision to include the material.

Immersed in horror

“The footage is uncomfortable, it is grim, it runs the risk of being voyeuristic, but at the same time it is an amazing opportunity,” says Richard. “We wanted the audience to experience it as it was experienced by the crew and we wanted to use it as a way of immersing them in the awful horror of Chris dying, while they watch on, helpless.”

No training could have prepared Chris for his situation. But for the rescuers their training kicked in. Dave had to bring Chris’s apparently lifeless body back to the bell where Duncan removed his helmet and gave him mouth-to- mouth resuscitation.

“Two breaths later and I gave out a couple of gasps and came round,” says Chris. “I had a groggy, drunken feeling.”

It was a freak accident with a freak outcome of survival, one that became legendary in the industry, and drew the attention of Da Costa and Parkinson. First a 45-minute in-house film was made for the sector, and then it was developed into a feature-length documentary. As for Chris, he’s still working as a diver.

‘Last Breath’ opens in cinemas on Friday and will be on the BBC in May