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[Webinar Recording] Talkin’ bout the evolution of intact stability

It’s been over 80 years since Jaakko Rahola defined and suggested the first intact stability criteria for Finnish vessels, although it wasn’t until 2008 that the IS Code made intact stability criteria mandatory at an international level. Whilst these requirements provide a solid foundation for ensuring a vessel’s stability, they don’t cover complex scenarios such as dynamic phenomena.  

As such, it’s time to welcome a second generation of standards to ensure vessels can operate at a higher level of safety. 

What does this look like?  

The Second Generation of Intact Stability isn’t intended to replace the existing criteria. Quite simply, it’s an extra set of guidelines intended to be used in tandem. It’ll address four key modes of failure: stability in waves, stability during navigation, stability when incapable of navigation, and dangers due to excessive stability.  

Unlike the binary pass-or-fail system of the original criteria, the new one introduces assessment levels, offering a more nuanced evaluation process. Starting with simpler checkpoints and gradually increasing in complexity, these new assessment criteria provide a thorough examination of a vessel’s stability. The resonance phenomenon of parametric roll, or dangers one could face when ‘surf-riding’ a wave, are just two examples of what is now considered in the assessment to reflect the multifaceted nature of the environment ships can face at sea. 

While the Second-Generation criteria are currently non-mandatory and in the trial phase, they represent a significant step towards enhancing safety standards in the maritime industry. Feedback on these new criteria is very valuable in further refining these guidelines before they are finalized, and therefore, the IMO encourages active participation and welcomes input from all stakeholders. 

Given that these guidelines may become standard in the upcoming years, it is well worth taking the time to familiarise yourselves with the criteria to get ahead of changes.  

Watch our latest webinar where our Lead Technical Consultant, Daniel Lindroth, goes into detail about the background, different modes of failure, and how to build confidence in the use of these new criteria. 



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