Near-miss: Dropped object fell from crane boom

  • Safety Flash
  • Published on 16 July 2015
  • Generated on 22 May 2026
  • IMCA SF 10/15
  • 2 minute read

A Member has reported a near miss incident in which an object was discovered which must have fallen from the crane boom.

What happened?

It happened during crane operations when it was noticed that a piece of steel measuring approximately 70mm x 40mm and weighing approximately 300g fell from the boom tip area to the deck. It was assumed (and investigation clearly indicated) that the object came from the inside of the crane hook pocket. This means that the object fell from approximately 100 metres.

The DROPS calculator suggests that such an object hitting a person from that height would have caused a fatality.

Location of incident

Location of incident

Dropped piece of steel

Dropped piece of steel

Internal condition of crane pocket

Internal condition of crane pocket

Diagram of incident

Our member’s investigation revealed the following:

  • Continuous movement of the main block inside the crane hook pocket caused damage to such an extent that a piece of steel broke loose and fell down
  • The crane hook pocket had been designed for storing the main block during transportation. The crane hook pocket could be locked against the boom using hydraulic pins
  • When using the auxiliary hook the crane hook pocket was locked against the boom. This caused steel on steel movement of the main block inside the crane hook pocket when booming up and down
  • Crane inspections only included load bearing parts of the crane
  • The crane hook pocket had been designed bearing in mind that the auxiliary hook would not be used frequently
  • No documentation was available on how this crane hook pocket should be used when using the auxiliary hook (locked against the boom or unlocked
  • An engineering bulletin from the crane manufacturer was not properly taken up by management.

Latest Safety Flashes:

Worker suffered crush injury while handling unstable steel plates

Steel plates suddenly toppled over to the side trapping a worker's left hand and wrist between a frame and an emergency stop pedestal.

Read more
High Potential Near Miss: Dropped object due to contact with crane sheave

A Dynamic Positioning (DP) beacon came into contact with sheave protection bars, resulting in the beacon and its holder assembly detaching and falling to the deck below.

Read more
Machinery damaged through improper maintenance technique

During an audit on an offshore vessel it was observed that the fuel oil purifier failed to self-discharge.

Read more
Shifting cargo and deck spill during heavy weather

A sodium chloride brine storage tank shifted approximately 0.5m during heavy weather conditions.

Read more
MSF: Fast Rescue craft (FRC) washed overboard and lost at sea

The Marine Safety Forum (MSF) has published Safety Alert 26-03 relating to the loss of a Fast Rescue Craft (FRC).

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.