Near-miss: Broken chain on self-propelled hyperbaric lifeboat (SPHL) recovery rigging

  • Safety Flash
  • Published on 9 June 2017
  • Generated on 15 March 2025
  • IMCA SF 14/17
  • 2 minute read

A self-propelled hyperbaric lifeboat (SPHL) was being lifted to the main deck for an hyperbaric reception facility (HRF) mating trial. 

What happened?

During this activity, the aft lifting chain on the SPHL broke whilst transferring the weight of the SPHL from the davits to the crane.

The SPHL was approximately 50 mm clear of the cradle when the aft chain snapped. At the time of the incident the crane reported an 8-tonne load. The dry weight of the SPHL was 13 tonnes. 

No persons were in the SPHL or in the immediate vicinity at the time of the incident. There were no injuries.

while a self-propelled hyperbaric lifeboat (SPHL) was being lifted onto the main deck for a trial, the SPHL's aft lifting chain broke while transferring the SPHL's weight from the davits to the crane

What went wrong? - Investigation and findings

  • The rigging had been sent ashore for annual testing and failed on-board the vessel, shortly after it had been inspected by a 3rd party.

  • The rigging was not tested as per 3rd party inspection procedures.

  • The rigging was being stored outside in open environment – this will have contributed to the condition of the chain.

  • A canvas sock around the rigging made it more difficult to inspect and see corrosion.

  • A chain link failed at 2 positions and appears to not be deformed – indicating existing crack propagation.

What were the causes of the incident?

  • Storage of the recovery rigging on top of SPHL exposed chain to the external environment – this contributed to the chain becoming corroded.

  • The Inspector:

    • Checked lower links of the chain only and did not inspect the section hidden by the protective cover.

    • Assumed that he had inspected sufficient percentage of the chain from which to infer the condition of the entire length; the chain under protective cover had significant corrosion.

What lessons were learned? And what were the actions?

  • All chain slings older than 12 months to be destroyed.

  • SPHL recovery rigging to be stored below decks and fitted only when SPHL is required.

  • Audit to be conducted of 3rd party to ensure compliance with inspection procedures. Improved liaison and communication with 3rd party auditor.

Latest Safety Flashes:

Divers helmet struck and damaged subsea by crane hook

During subsea spool tie-in operations, a crane hook unexpectedly struck a diver’s helmet. 

Read more
Diver lifted off seabed

A diver was lifted off the seabed when their umbilical was caught by a diving bell clump weight adjustment prior to bell recovery.

Read more
MAIB: Very serious leg injury during crane operations

The UK Marine Accident Investigation Branch (MAIB) published Accident Investigation Report 11/2024 into an incident where a crew person was seriously injured while operating a crane.

Read more
Person fell in engine room and injured head

An oiler sustained head injuries while working alone in the engine room.

Read more
MSF: Cook got chemicals in eye

The Marine Safety Forum (MSF) published Safety Alert 24-10 relating to an incident in which a cook got chemicals splashed in the eye.

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.