Five men boiled alive in 'most gruesome' North Sea diving tragedy

The Byford Dolphin (Image: Reuters)

In one of the most horrific incidents ever recorded, five men were boiled alive from the inside out due to a momentary miscalculation 1,000 feet below sea level.

Back in 1983, the Byford Dolphin, a semi-submersible oil drilling rig, was operating at various sites in the North Sea. The rig was no stranger to accidents, but the worst incident involved exploding organs, boiling blood and a man killed by a diving chamber.

A team of four British and Norwegian divers - Edwin Arthur Coward, 35, Roy P. Lucas, 38, Bjørn Giaever Bergersen, 29, and Truls Hellevik, 34 - along with tenders William Crammond, 32, and Martin Saunders, 30, were assembled to undertake a deep-sea diving mission on the rig.

To safely conduct deep-sea operations, the divers had to be confined to a series of compression chambers over a 28-day period. According to Lad Bible, these highly sensitive chambers prevent a build-up of nitrogen in the bloodstream.

The pressurised living quarters could be accessed through a diving bell, a ring-shaped chamber, which was sealed off from other parts of the underwater station, reports the Mirror.

The semi-submersible drilling rigs Byford Dolphin (Image: Wirestock via Getty Images)

The method employed was known as saturation diving - it extended the duration divers could remain underwater and averted the painful and often fatal accumulation of nitrogen when resurfacing.

Ascending to the water's surface causes nitrogen and helium to dissolve into the bloodstream of divers, which can be lethal.

Hence, in the chambers, divers breathe a specific mix of gases - typically helium and oxygen, adjusted according to the depth of the dive.

If divers ascend too rapidly, the abrupt drop in pressure triggers decompression sickness. On the ill-fated day of 5 November 1983, Bergersen and Hellevik were returning to the chamber via the diving bell, assisted by tenders Crammond and Saunders.

To safely transition between chambers, the diving bell needed to be sealed to prevent decompression sickness. However, a catastrophic mechanical failure resulted in the bell being released seconds before Hellevik had managed to shut the chamber door.

The Byford Dolphin oil rig and its safety ship is seen in the North Sea (Image: Bloomberg via Getty Images)

The internal crew chambers were supposed to be pressurised to nine atmospheres, but in this case, they plummeted to one within a fraction of a second. Crammond was killed when he was struck by the rogue diving bell, while the four divers perished instantly as the nitrogen in their blood transformed into bubbles, effectively boiling them from within.

Hellevik was propelled through a 60cm wide opening, the intense pressure causing his organs to be expelled from his body. Saunders was the sole survivor of this dreadful event, enduring collapsed lungs, back fractures and a broken neck.

An official inquiry concluded that human error was the cause of the fatalities. The incident continues to baffle as its precise cause remains elusive, but it underscored the pressing need for enhancements in diving safety.

It has been cited as one of the most gruesome deaths (Image: undefined)