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Damage to chain hoist subsea

What happened

Whilst divers were lowering a large clamp for installation, the chain block used to centralise the clamp on the horizontal member became trapped in the hinge point on the clamp. The clamp was opened when it was noticed and damage to the chain link was observed. There was no damage to the clamp itself.

Chain caught in the hinge side of clamp
Layout of clamp from procedure

What were the causes?

  • Although initial checks of the worksite were performed, checks were not frequent enough during the task of  lowering and closing the clamp;
  • Whilst the procedure did include a safety note on awareness around pinch points, however, it did not specify any checks the hoist chain or loose items of rigging;
  • There was no prompt for entanglement or snagging hazards included in the dive team procedures.

The root cause was found to be that the procedures did not identify and highlight entanglement or snagging hazards.

What our member did

  • Caused heightened awareness around snagging hazards when operating chain lever hoists;
  • Reviewed procedures to include a prompt for the use of chain / lever hoists identifying the risk of entrapment of chains.

Members may wish to refer to:

Safety Event

Published: 24 October 2022
Download: IMCA SF 23/22

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