A horrifying incident on the Byford Dolphin oil rig on 5 November 1983 resulted in the instantaneous death of five workers, with a sixth narrowly escaping death but left with life-altering injuries. The crew were carrying out routine maintenance work at the time, according to a YouTube video that has now garnered over 5 million views.

The video explains how the men met their tragic end while working on the oil rig situated in the North Sea near Norway after an abrupt pressure change wreaked havoc on their bodies. Roy Lucas, 38, Edwin Coward, 36, Truls Hellevik, 34 and Bjorn Giaever, 29, William Crammond, 33, and Martin Saunders, 30 were all on duty on the rig at the time of the catastrophe.

The extreme pressure caused three men's bodies to explode into countless pieces, and another was crushed to death. The final man killed in the accident was sucked through a small hole causing his organs to be expelled from his body.

The diving team descended to a depth of 295 feet to carry out their work and used a special chamber known as a diving bell to transport workers.

The diving bell was linked to another set of chambers where divers temporarily resided, and these areas enabled them to transition from the high-pressure underwater environment to pressurised living quarters. Pressure underwater increases as humans descend deeper, reports .

However, the primary risk arises not from descending further into the depths but rather from ascending from the depths below.

Rising towards the surface can cause nitrogen and helium to dissolve into a diver's bloodstream, which can be perilously dangerous. That's why divers in the chambers breathe a specialised blend of gases - typically helium and oxygen, adjusted according to the depth of the dive.

If divers ascend too rapidly, the swift release of pressure results in decompression sickness.

This causes the dissolved nitrogen in the bloodstream to revert back to gas, forming nitrogen bubbles throughout the body. Symptoms include nausea, joint pain and dizziness, and in some instances, it can even lead to death.

The only prevention is a careful ascent to the surface, allowing time for the nitrogen to naturally diffuse.

The diving team were scheduled to spend up to 28 days in the confined high-pressure chamber where they worked, ate and slept together. On the day of the tragic incident, Hellevik and Giaever had just finished 12 hours of maintenance work at a depth of 295 feet, as reported by the Daily Mail.

After their shift, the team ascended back to the surface using the diving bell, which was expected to be reconnected to the diving chambers. The diving tenders, who controlled the air supply to the maintenance team, had also been working for 12 hours at that point.

Once inside from the diving bell, the two divers sealed the door and adjusted the chamber's pressure to ensure it was securely shut. They would typically then isolate the chamber and connect it to the dive bell before gradually depressurising it for the divers' safety.

However, on that fateful day, one of the divers outside the bell unlatched it prematurely before it had been properly depressurised. This open clamp caused the chamber system to abruptly shift from the pressure of 297 feet underwater to the air pressure at the surface.

The explosive rush of air out of the chamber propelled the diving bell violently, striking Crammond and killing him instantly, while leaving Saunders partially crushed by the 4000 kg object. Saunders suffered collapsed lungs and fractures in his back - as well as a broken neck, but he was the sole survivor on board.

The other divers met a far more gruesome fate as the pressure ripped through the living chamber, yanking Hellaevik off his feet and causing instantaneous death for those inside, according to YouTube channel Storified.

The three divers Lucus, Coward and Giaever - who were resting before their shift - died instantly. As per Storified, the sudden change in pressure caused dissolved nitrogen to revert to a gas state before solidifying in their arteries, veins, hearts and other organs.

The horrific outcome saw their body parts strewn throughout the chamber.

Hellevik endured the most horrific death as he was nearest to the partially closed connecting door. He was propelled through a 24-inch (60.9 cm) gap with a force of 25 tons, causing his organs to explode out of his body.

The incident remains an enigma as the exact cause is still unclear, but it highlighted the urgent need for improvements in diving safety.