LTI – worker fractured arm during mooring line handling

  • Safety Flash
  • Published on 3 October 2023
  • Generated on 30 July 2026
  • IMCA SF 23/23
  • 2 minute read

A mooring rope (weighing 2.9 kg per metre) hit a crew member and broke their arm. 

What happened?

A mooring rope (weighing 2.9 kg per metre) hit a crew person and broke their arm. 

The incident occurred as crew were preparing to unmoor and move a barge.

The operation was proceeding as planned when one of the forward mooring station winches in use tripped out.

The mooring crew at the forward station informed the Chief Officer about the winch tripping, using UHF.

The mooring crew at the aft mooring station, on hearing this information, decided to stop the barge by adding an additional coil on the bollard.

Whilst one of the crew was attempting to coil the rope on the bollard, due to a sudden increase of tension on the line, control of the rope was lost, and the rope hit the worker on the left forearm causing the injury.

The injured person received first aid treatment promptly and was subsequently evacuated by helicopter.

Instructions  were given to secure the mooring rope “in slack” by  adding another loop into the bollard. However, the  barge was already moving and the mooring line  came under tension due to that movement. The  injured person was in an unsafe position, with his  arm in the line of fire.

LTI – worker fractured arm during mooring line handling

What went wrong?

Confusion, because there was a lack of clear communication with no proper instructions during the operation.

The radio communication addressing the tripped winch was misunderstood at the aft mooring station as an "ALL STOP" signal.

Instructions were given to secure the mooring rope "in slack" by adding another loop into the bollard. 

However, the barge was already moving and the mooring line came under tension due to that movement.

The injured person was in an unsafe position, with his arm in the line of fire.

Lessons and actions taken

  • Over-confidence may lead to poor judgement and making mistakes – if in any doubt, follow the instructions.

  • Minimise confusion and ensure there are clear and properly understood communications.

  • Our member arranged:

    • further training on Line of Fire risks

    • refresher training for marine crew regarding hazards in mooring operation

    • awareness sessions customised to the role and responsibility of the Team Leaders and Supervisors, addressing the key elements of their duties.

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