Podcast
Questions and Answers
During the subsea spool tie-in operations, what led the Diving Supervisor to believe the crane hook had reached the seabed?
During the subsea spool tie-in operations, what led the Diving Supervisor to believe the crane hook had reached the seabed?
- Sonar imaging indicated the hook was on the seabed.
- The crane operator visually confirmed the hook's position.
- The diver provided confirmation via underwater communication.
- The crane operator reported there was 'no weight' on the crane wire. (correct)
What critical factor contributed to the crane hook striking the diver's helmet during the subsea operation?
What critical factor contributed to the crane hook striking the diver's helmet during the subsea operation?
- Incorrect use of the diver's personal protective equipment.
- Failure of the crane's braking system.
- Inadequate length of the crane pennant or stinger. (correct)
- Sudden and unexpected shifts in the seabed.
Besides the length of the crane pennant/stinger, what other condition significantly increased the risk of the incident?
Besides the length of the crane pennant/stinger, what other condition significantly increased the risk of the incident?
- The diver's lack of experience in subsea operations.
- Poor visibility hindering the ability to observe the crane hook's position. (correct)
- Strong underwater currents pushing the diver.
- Malfunctioning communication equipment.
To prevent similar incidents, what measure should be implemented in environments with poor visibility during subsea operations?
To prevent similar incidents, what measure should be implemented in environments with poor visibility during subsea operations?
Based on the incident, what is the most important aspect of communication that needs to be reinforced during subsea operations to ensure safety?
Based on the incident, what is the most important aspect of communication that needs to be reinforced during subsea operations to ensure safety?
Flashcards
Subsea Crane Hook Incident
Subsea Crane Hook Incident
During subsea spool tie-in operations, a crane hook unexpectedly struck a diver's helmet due to the crane operator assuming the hook had reached the seabed, leading to the hook slipping and striking the diver.
Causes of Crane Hook Incident
Causes of Crane Hook Incident
Insufficient length of the crane pennant or stinger, and poor visibility hindered accurate observation, leading to a crane hook striking a diver's helmet during subsea operations.
Adequate Distance
Adequate Distance
Maintaining a safe distance between divers and the crane hook during subsea operations reduces the risk of accidental contact, especially in low visibility.
Enhanced Visibility Aids
Enhanced Visibility Aids
Signup and view all the flashcards
Reinforce Communications
Reinforce Communications
Signup and view all the flashcards
Study Notes
Incident Overview
- During subsea spool tie-in operations, a crane hook struck a diver's helmet.
- The incident occurred during subsea spool tie-in operations in poor visibility conditions.
Sequence of Events
- Divers were working on the seabed.
- The Diving Supervisor instructed the crane operator to lower the crane hook to allow the diver to disconnect rigging from crane.
- The crane operator reported 'no weight' on the crane wire.
- Diving Supervisor assumed the hook had reached the seabed.
- The diver proceeded with disconnecting the PHF.
- The crane hook unexpectedly struck the diver's helmet while the diver was beneath the PHF.
- The diver was reported unharmed and returned to the dive bell, the dive was aborted.
- Helmet inspected and determined to be damaged beyond repair, specifically the side block.
- The helmet's integrity was maintained, demonstrating the durability of the diving helmets.
Positive Outcomes
- Diver 2 assisted Diver 1, preventing injuries.
- Both divers returned to the dive bell safely.
- Locating beacons on divers and the crane block enabled accurate tracking.
- Procedures, lifting plans, and Job Hazard Analysis (JHA's) were followed.
- The diver was uninjured due to the helmet absorbing the impact.
Incident Factors
- Crane hook lowered for PHF rigging disconnection rested on the top beam of the PHF.
- Resting on the beam resulted in a 'no weight' reading, misleading the crane operator.
- As the diver approached the disconnection point, the hook slipped and struck the diver's helmet.
- Cause: inadequate length of crane pennant/stinger.
- Cause: poor visibility hindered the ability to observe the crane hook position.
Recommended Actions
- Ensure adequate distance between divers and crane hook using a sufficiently long crane pennant/stinger, especially in limited visibility.
- Use enhanced visibility aids and monitoring, such as additional locating beacons, underwater cameras, or sonar, to track critical equipment.
- Reinforce communications and challenge assumptions about equipment position.
- Implement clear communication between the dive supervisor, crane operator, and divers regarding equipment location.
Additional Actions Taken
- Updated project procedures to specify minimum pennant lengths for different operations.
- Conducted pre-operation inspections of rigging and lifting equipment to ensure safety standards.
- Updated the Job Hazard Analysis (JHA) to incorporate lessons learned about safe distances, visibility, and communication for subsea lifting operations.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
