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Near-miss: Crane hook block dropped to deck

A member has reported an incident in which a crane winch wire parted and the hook block was dropped to deck. The incident occurred when the crane operator began to extend the jib of the crane without letting out the winch wire at the same time. The extending jib caught the hook block and caused the crane winch wire to part. The hook block, which weighed 30kg, dropped 10 metres (m) to the deck. There were no injuries.

Crane following incident
Crane following incident

An investigation revealed the following:

  • The crane operator was not paying proper attention to the extending jib;
  • The crane operator had not informed his supervisor that this work was taking place;
  • The crane operator was effectively working alone: there was no-one else watching the crane whilst it was being operated;
  • There was no locking or warning mechanism fitted to the crane to prevent this from happening.

The following measures were taken to prevent recurrence:

  • Review training of persons operating cranes and winches;
  • Review of risk assessment for this job;
  • Investigate installation of lock protection sensors for this kind of crane.

Safety Event

Published: 25 January 2012
Download: IMCA SF 01/12

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