A small mistake in operating equipment caused a group of divers working on an oil rig in the North Sea in 1983 to experience a tragically painful death.
Deep diving is a risky activity, primarily due to the risk of decompression sickness. To minimize this risk, divers must ascend slowly at the end of their exploration. On oil rigs, where equipment needs frequent inspection and adjustment, this can delay operations. To address this, divers are sometimes placed in a saturation chamber. This specially designed chamber is equipped with beds, essential supplies, and various living amenities, pressurized to match the underwater environment where the divers are working.
The scene of the explosion at the Byford Dolphin oil rig. (Photo: StarPulse).
According to the U.S. National Oceanic and Atmospheric Administration (NOAA), when saturation diving, divers stay at depth long enough for all the tissues in their bodies to equilibrate with the pressure of the gas mixture in their tanks. Most recreational and scientific diving requires divers to undergo hours of decompression before returning to the surface after each dive. Saturation diving saves time by allowing divers to be under high pressure for the entire duration. The saturation chamber is filled with a mixture of oxygen and helium to prevent nitrogen buildup in the blood, with the side effect that divers inside the chamber must speak loudly.
The worst accident in diving history occurred in the North Sea in 1983. On November 5, 1983, at the Byford Dolphin rig off the coast of Norway, a diving bell was raised from the ocean and attached to the saturation chamber. The chamber contained compartment 1, which held Edwin Coward and Roy Lucas, and compartment 2, which housed Bjørn Bergersen and Truls Hellevik, divers who had just returned from a shift. The diving bell was connected to compartment 1, operated by two maintenance workers, William Crammond and Martin Saunders.
The pressure in these areas must always be maintained at balanced levels to ensure the diving bell can detach easily. The maintenance workers responsible for this had to follow a strict 5-step procedure, which included: closing the diving bell, increasing the pressure in the bell to seal the door, closing the door between compartment 1 and the connection chamber, reducing the pressure in the connection chamber, and finally unlocking to allow the diving bell to detach.
However, while the doors of the compartments were closing, Crammond unexpectedly unlocked the diving bell. The entire connection chamber suddenly became exposed to normal atmospheric conditions, leading to a pressure differential that caused the system to explode. All four divers faced an explosion that exceeded the human body’s capacity to endure, resulting in their immediate deaths, with bodies left disfigured. The air from the connection chamber also propelled the diving bell outward, striking the two maintenance workers, killing one and severely injuring the other.
The sudden pressure differential caused the blood of 3 out of the 4 divers to boil and vaporize. For the fourth diver, the pressure caused his body to explode, with organs ejected several meters away. Autopsy results revealed that the organs were even still intact.
This deadly accident led to the establishment of the North Sea Divers Alliance. Although the investigation report concluded that the accident was due to human error, the Alliance still decided to file a lawsuit against the rig for lacking adequate safety equipment. After 26 years of struggle, investigators determined that the rig had faulty equipment that led to the accident, absolving Crammond of responsibility. The families of the victims also received compensation for their loss.
