Failed chain link – catastrophic failures in mooring system

  • Safety Flash
  • Published on 14 July 2011
  • Generated on 21 April 2025
  • IMCA SF 06/11
  • 1 minute read

The Bureau of Ocean Energy Management Regulations & Enforcement (BOEMRE) has published Safety Alert No. 296 regarding the catastrophic failure of a chain link in a mooring system, which could have put a floating structure at risk.

In the incident, a single point mooring system failed at the tether chain for a free-standing hybrid riser, allowing the buoyancy air can and the free-standing flow line riser to separate. The 440-ton buoyancy air can rose suddenly to the surface while the free standing riser collapsed.

Further information may be found here.

Latest Safety Flashes:

Fatality following a fall from a wind turbine

The Scottish Courts and Tribunals Service, and UK HSE, has published a response to a fatal incident in which a crew member fell to their death.

Read more
UK HSE: Risk of collision with offshore installations from attendant vessels

The UK Health and Safety Executive (HSE) has published Safety Notice ED01-2025 relating to the risk of collision with offshore installations.

Read more
USCG: Hazardous Zone Markings and Safety Protocol Awareness

The United States Coastguard has published Safety Alert 04-25 relating to the importance of Hazardous Zone Markings and Safety Protocol Awareness.

Read more
BSEE: Crane safety awareness during offshore helideck operations

BSEE published Safety Alert 491 relating to a the investigation of a near miss crane incident on an offshore platform.

Read more
Incidents occurring during decommissioning

IMCA has put together a summary of incidents relating to decommissioning.

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.