Near-miss: Dropped object fell from crane boom

  • Safety Flash
  • Published on 16 July 2015
  • Generated on 13 December 2024
  • 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:

LTI: Finger injury during emergency recovery of ROV

A worker suffered a serious finger injury when their finger was caught between a crane wire and the recovery hook on an ROV.

Read more
BSEE: recurring hand injuries from alternative cutting devices

The United States Bureau of Safety and Environmental Enforcement (BSEE) has published Safety Alert 487.

Read more
NTSB: Crane wire failure

The National Transportation Safety Board of the United States (NTSB) published "Safer Seas Digest 2023".

Read more
Hot work performed outside of Permit to Work (PTW) boundary limit

A near miss occurred when a third-party contractor working removed a trip hazard from the vessel main deck, using a cutting torch and grinding disc.

Read more
Vital safety information (height of vehicle) found incorrect

“Height of vehicle” information displayed on a truck, was found to be incorrect.

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.