Improper use of heaving line

  • Safety Flash
  • Published on 17 December 2019
  • Generated on 16 August 2025
  • IMCA SF 30/19
  • 1 minute read

During a mooring operation, vessel crew were found to be using a 4-ton shackle attached to a heaving line (instead of proper “monkey fist”). 

4 ton shackle attached to a heaving line
The crew did not have an available heaving line with a “monkey fist”.

What went wrong?

The crew did not have an available heaving line with a “monkey fist”.

What actions were taken?

  • Risk assessment for mooring operations to be reviewed.

  • A check to be included to ensure that a sufficient number of heaving lines with “monkey fist” are available.

    • In this case, at least 9 heaving lines were to be kept on the vessel (2 for use at each mooring station plus 1 spare).

Members may wish to refer to:

  • IMCA HSS029 - Mooring practice safety guidance for offshore vessels when alongside in ports and harbours

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