Waage Drill II diving accident facts for kids
| Date | September 9, 1975 |
|---|---|
| Location | Bruce oil field, East Shetland Basin, North Sea, Scotland |
| Cause | rapid pressurization of chamber |
| Participants | Peter Henry Michael Holmes, Roger Baldwin |
| Outcome | death due to hyperthermia |
| Inquiries | Fatal accident inquiry (Scotland), March 30–31, 1977 |
The Waage Drill II diving accident happened on September 9, 1975. Two divers sadly died from heatstroke because the special room they were in was accidentally filled with too much helium gas.
What Happened Before
On September 9, 1975, two divers named Peter Holmes (29) and Roger Baldwin (24) had just finished a job deep under the North Sea. They had been lowered in a special diving bell to about 390 feet (119 meters) to clear some rope tangled around oil equipment.
After their work, they were pulled up in the bell. The plan was to slowly bring them back to normal pressure. They needed to move from the diving bell into a connected room called an "entrance lock," and then into a larger "chamber" where they would stay for a while. This process is called "decompression" and "saturation," which helps divers safely return from deep water.
The diving system had many gauges and valves to check the pressure inside the chambers. One very accurate gauge, called the Heise gauge, was used to watch the divers' depth. The supervisor would set this gauge to follow the divers as they moved from the bell into the chambers. This was done to make sure the divers were always at the correct pressure. Once the divers were safely inside the main chamber, the supervisor was supposed to reset the valves so the gauge would show the pressure of that chamber.
The Accident
At 9:50 PM that night, the diving bell was connected to the entrance lock. But a gas leak started where the bell and lock joined. The crew tried again, and the bell finally sealed properly.
Divers Holmes and Baldwin then started to move from the bell into the entrance lock. Suddenly, the gas leak returned. The pressure started to drop quickly. To keep the divers safe, the supervisor told them to quickly move into the first main chamber. They leaned against the door from the inside while the supervisor added a little helium gas to seal the door.
At this critical moment, the supervisor forgot to reset the valves for the Heise gauge. This meant the gauge was still showing the pressure dropping from the leak, but it was NOT showing the pressure inside the chamber where the divers were. The supervisor thought the chamber door wasn't sealed, so he kept pumping large amounts of pure helium gas into the chamber where Holmes and Baldwin were.
By the time the supervisor realized his mistake, it was too late. Holmes and Baldwin had been quickly pressurized from 310 feet (94 meters) to 650 feet (198 meters) in just a few minutes. This fast increase in pressure, along with the helium gas (which transfers heat very well) and the humid air, made the temperature inside the chamber shoot up. It went from about 90°F (32°C) to a scorching 120°F (49°C).
The two divers tried desperately to open the chamber door to escape, but they couldn't. They took the mattresses off their beds and lay on the cooler metal floor. But they were forced to breathe the extremely hot air. Sadly, they died several hours later from hyperthermia, which is when your body gets dangerously overheated.
The Investigation
Later, an official investigation called a "fatal accident inquiry" looked into what happened. The judge in charge said that the way the diving system was designed and labeled made it very easy for human error to happen, especially during an emergency.
The safety officer for the company, Oceaneering, said that the way the control panel was set up "helped cause" the accident. He believed the accident probably wouldn't have happened if the first chamber had its own special pressure gauge that only showed its pressure. If there had been such a gauge, the supervisor wouldn't have been confused by the Heise gauge and wouldn't have pumped so much helium into the chamber.
