Failed chain link – catastrophic failures in mooring system
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 can be found in the linked IMCA Safety Flash PDF.
Safety Event
Published: 14 July 2011
Download: 
IMCA SF 06/11
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