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High potential: dropped chain assembly

What happened

A chain assembly weighing 2.3kg fell 10m to deck, just glancing the helmet but potentially causing fatal injuries to a worker below. The incident occurred during lowering of a two-legged chain and a soft sling.  The sling was flapping around due to the wind (9 m/s) and got caught on a railing. The hook flipped upside down and the master link of two legged chain was released from the hook.  Consequently the chain fell 10 meters, grazing the helmet of the person working below.  The person was shocked but otherwise unharmed.

Sling preventing proper closing of the hook

What went wrong?

  • The lifting technique was not correct: The fibre of the soft sling was caught in between the hook and latch preventing the safety mechanism from locking;
  • People were in unsafe positions:
    • The person with the remote control on the external platform did not have view of the load he was lowering;
    • The injured person was working within the lifting area under the load when the chain and sling was being lowered. 
  • Insufficient communication: There was no communication between the two work areas when the chain assembly was being lowered.

Lessons learned

  • Always check the lifting accessories are placed correctly in the hook;
  • Ensure there are no people under the load – including the rigging itself which is also to be considered a load;
  • Always keep an eye on the lift.
  • Communicate lifts and inform team members on restricted areas;
  • Does the crew have sufficient experience to perform the given tasks safely?
  • Supervise less experienced colleagues;
  • Follow the Life Saving Rules; wear PPE.

Members may wish to refer to:

Safety Event

Published: 3 August 2023
Download: IMCA SF 19/23

Relevant life-saving rules:
IMCA Safety Flashes
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