Bibby Topaz:
Incident Date: 18/09/12.
Weather conditions: 30 knots, 316° Sea State: 5
The dive team of two men on the sea bed and a further man in the diving bell were carrying out testing within a subsea structure.
At 22.10 a series of alarms activated in the vessels wheelhouse in relation to the Dynamic Positioning (DP) system. The amber alarm was initiated by the Bridge and Dive Control was informed that the vessel had a problem with the DP System.
The Dive Supervisor immediately ordered the Divers to leave the structure and head back to the diving bell. Both divers had left the structure and were on top of the drilling template structure when there was loss of position by the vessel and it started to drift off location. The red light alarm was initiated; Dive control was informed and both divers instructed to get back to the bell stage as soon as and as safely as possible.
At this point Diver 2 noticed his umbilical had been snagged on the side of the subsea structure close to the top. He began trying to free his umbilical and requested slack.
At approximately 22:12 hrs, with the vessel still drifting all communications and video was lost to Diver 2. On the Bridge the DP operator, Chief Officer and Master were trying to regain control of the vessel by manual operation of the thrusters.
The Bridge was in communication with dive control and was informed that Diver 1 was safely back on the bell stage and that Diver 2’s umbilical had been severed. At this point Diver 2 had reverted to his standby breathing gas supply.
At 22.17 hrs the Bridge team had regained control of the vessel having drifted off approx 240m and made heading back towards a position directly above the subsea structure. The vessel was being driven manually by the Master.
The team monitored Diver 2’s locator beacon; this was seen to be located on top of the structure. The Remote Operated Vehicle (ROV) headed back towards the drilling template and confirmed Diver 2’s location on top of the drilling template structure.
At 22:40 hrs the vessel was back in a position close to the drilling template. The bell was lowered as close as possible above the structure to assist with the recovery of Diver 2.
Diver 1 left the bell stage to begin recovery of Diver 2 back to the bell with the ROV closely monitoring the operation. Both Divers were on the bell stage at 22:46 hrs, with Diver 2 being recovered into the bell at 22:48 hrs.
With Diver 2 safely recovered into the bell the Bellman (Diver 3) reported that Diver 2 was unconscious but breathing. However as soon as his diving helmet was removed Diver 2 regained consciousness and was provided with hot water to his suit to warm him up.
The bell, bell umbilical and the bell wires were surveyed by the ROV for signs of damage that could potentially impede the safe recovery of the bell. Once this was complete the bell was recovered as per normal procedure. All Divers were transferred to the chamber system and treatment was provided to Diver 2 which included being put on therapeutic oxygen.
The Medic was in attendance in saturation control and communication was also established with the shore side Diving Doctor. After consultation with the medical team a routine decompression schedule of the dive team commenced.
Decompression was completed on the 22[SUP]nd[/SUP] September following which all Divers were given a thorough check by a doctor. Diver 2 also attended hospital for further checks on 23[SUP]rd[/SUP] September and all Divers have received a clean bill of health.
Bibby Offshore would like to praise the skill, professionalism and expertise of the crew of the Bibby Topaz in carrying out the safe recovery of Diver 2.