One Second of Error: The 1983 Accident That Killed 5 Men Through Explosive Decompression

At 4 a.m. on November 5, 1983, a single mechanical failure on a North Sea oil rig killed five men. The deaths weren't from a fire or a fall; they happened in a fraction of a second through a phenomenon so violent it's still a core lesson in diving safety four decades later: explosive decompression.

The incident occurred on the Byford Dolphin, a semi-submersible drilling rig operating in the Frigg gas field. The five men—four divers and a tender—were inside a pressurized chamber system. They were living under conditions equivalent to deep-sea pressure, a technique known as saturation diving, which allows divers to work at great depths for long periods.

From 9 Atmospheres to 1 in a Flash

The fatal error happened during a routine procedure. A clamp connecting their living quarters to a diving bell was released prematurely, before the bell's own hatch was sealed. This single action caused the pressure in their habitat to plummet from nine times normal atmospheric pressure (9 atm) to one in an instant.

The physics of this rapid pressure drop were unforgiving. As the pressure vanished, the nitrogen in the divers' blood and body fluids instantly turned to gas, essentially boiling from the inside. The process was so quick and so destructive that there was no time to react. The tragedy serves as a grim example of how a quick procedural oversight in a high-tech environment can lead to catastrophic failure.