Safety Alert
Worker Struck by Tensioning Tool

Country: THAILAND - Asia/Australasia

Location: OFFSHORE : Floating Production Storage Unit

Incident Date: 6 October 2017   Time: 11:00

Type of Activity: Maintenance, inspection, testing

Type of Injury: Struck by

Function: Production

A 4 yearly task to check the tension of bolts on the bearing of an FSO turrret was in progress. During moving the bolt tensioner, a part (the puller, weighing 13kg) fell between the bearing stud bolts of the inner (static) and outer (rotating) bearing races. Before it could be removed the FSO weathervaned trapping and compressing the tensioner part between the two rings of bolts. A crew member went to investigate further. As he crouched over the tensioner part it suddenly freed and struck him in the head causing serious injury. He was medevaced promplty to hospital onshore.

Figure 1: Turret working location

Figure 2: Tensioner part trapped between bearing race stud bolts


What Went Wrong?:

The risk of a tensioner part falling and becoming trapped between the stud bolts was not recognised in the Job Safety Analysis, work procedure or turret vendor documentation. Also as this risk was not recognised the crew member placed himself in the line of fire. No Stop Work Authority was applied when the task deviated from the expected work process. The design of the turret bearing races and stud bolts location allowed the tensioner part to become trapped and compressed when the FSO weathervaned.

Corrective Actions and Recommendations:

  • Provide additional safeguarding tools and equipment to prevent the tensioner puller from dropping in between the inner and outer stud bolt or even this tool and equipment could help to support the re-tensioner while moving along the race.
  • Investigate a manual handling tool that will reduce the risk of accidentally dropping the tensioner parts.
  • Review the Job Safety Analysis and work procedure to include routine and unexpected risks and provide troubleshooting guidance. Include JSA to consider weather limits for the work and use of a tug on the FSO stern.
  • Reinforce use of Stop Work Authority if work deviates from normal conditions. Investigate if this task should be performed by a specialist contractor rather than the FSO crew.
  • Develop "line of fire" awareness training.
  • Share information with other operating asset with a FPSO and future project FSO to design out the hazard, e.g. put the two bearing rces and rings of bolts at different elevations.

Safety Alert number: 293
IOGP Safety Alerts


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