8th session of the Sub-Committee on Ship Design and Construction (SDC 8)

By Hendrike Kühl, IUMI Policy Director

The eighth session of the Sub-Committee on Ship Design and Construction (SDC), which was postponed to 2022 due to the Covid-19 pandemic, was held remotely from 17 to 21 January 2022. The session was chaired by Ms Turid Stemre from Norway. Key issues discussed at the meeting included:


Second generation intact stability criteria

Mandatory criteria and recommended provisions regarding intact stability are set out in the International Maritime Organization’s (IMO) 2008 Intact Stability (IS) Code, which is mandatory under chapter II-1 of the International Convention for the Safety of Life at Sea (SOLAS) and the 1988 Load Lines Protocol. Advanced computer technology and intensive research have enabled "second generation" intact stability criteria to be developed, for a comprehensive safety assessment of ship dynamics in waves.

The Sub-Committee agreed draft Explanatory Notes to the Interim Guidelines on second generation intact stability criteria which are being used on a trial basis, following their approval by Maritime Safety Committee (MSC) 102. The Explanatory Notes provide administrations and the shipping industry with specific guidance to assist in the uniform interpretation and application of the Interim Guidelines.

The Interim Guidelines address vulnerability criteria, direct stability failure assessment and operational measures and contain performance-based criteria for assessing five dynamic stability failure modes in waves: dead ship condition, excessive acceleration, pure loss of stability, parametric rolling and surf-riding/broaching. The reference to "second generation" derives from the fact that they are based on first principles and latest technology, as opposed to predominant use of casualty records which form the basis of the mandatory intact stability criteria.


Safety measures for non-SOLAS ships operating in polar waters

Neither SOLAS nor the draft guidelines for non-SOLAS ships operating in polar waters cover pleasure yachts of 300 gross tonnage and above and less than 500 gross tonnage engaged in trade (i.e. commercial yachts) or cargo ships of 300 gross tonnage and above and less than 500 gross tonnage. MSC 102 had agreed that safety guidelines should also be developed for those ship types operating in polar waters. The Sub-Committee decided to invite proposals for the development of safety measures for these ships to SDC 9.

Moreover, a proposal for a unified interpretation relating to the ice accretion and the intact and damage stability under the Polar Code was submitted by International Association of Classification Societies (IACS). Given the wide scope of the matter which could result in unintended consequences, invited interested delegations to submit a revised proposal to a future session.


Reducing underwater noise from ships

SDC 8 began a review of the 2014 Guidelines for the reduction of underwater noise from commercial shipping. The international community recognises that underwater-radiated noise from ships may have negative consequences on marine life, especially marine mammals. The aim of the review is to provide updated recommendations based on the latest developments in ship design and technology and to address the barriers to their uptake in an effort towards a significant reduction of underwater-radiated noise from ships.

A complete report of the meeting is available HERE.