Incorrectly Weighted Monkey’s Fist

  • Safety Flash
  • Published on 30 October 2018
  • Generated on 11 January 2026
  • IMCA SF 24/18
  • 1 minute read

The Marine Safety Forum (MSF) have published Safety Alert 18-22 in which a ‘monkey’s fist’ had been thrown ashore during a mooring process. 

A quayside boatman reported his concerns on this.

The images show the condition of the ‘monkey’s fist’ when it was thrown ashore, showing an area of protruding concrete. Upon inspection of the monkey’s fist, it was noted that it was heavier than normal. The object was cut open and the inside was found to be concrete, together with two layers of rope making up the outer layer. Should the ‘monkey’s fist’ have struck anyone upon thrown overboard, it had the potential to cause serious injury.

Monkeys fist
Monkeys fist
Concrete inside monkeys fist

What actions were taken?

  • The dangers and potential for injury was discussed with the vessel.

  • A safety memo was created in order to share the learnings from this incident.

The safety alert can be viewed on the MSF’s website.

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