Sub-Committee on Ship Design and Construction (SDC 8), 17-21 January 2022

Reducing underwater noise from ships

The IMO Sub-Committee on Ship Design and Construction (SDC 8), which met in remote session 17-21 January 2022, began its work to review the 2014 Guidelines for the reduction of underwater noise from commercial shipping to address adverse impacts on marine life (MEPC.1/Circ.833). The guidelines focus on primary sources of underwater noise, namely on propellers, hull design, onboard machinery, and various operational and maintenance recommendations such as hull cleaning.

The review has been initiated after the issue was raised at the Marine Environment Protection Committee (MEPC). The international community recognizes that underwater-radiated noise from ships may have both short and long-term 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 and measurable reduction of underwater-radiated noise from ships.

A working group discussed a number of submitted documents and developed a work plan and terms of reference for a correspondence group, which were agreed by the Sub-Committee.

The correspondence group is tasked with, inter alia: enabling engagement of Inuit and other indigenous communities and the incorporation of Indigenous Knowledge; identifying comparable and common means of measuring, analysing and reporting of underwater radiated noise emissions from ships (e.g. existing and developing ISO and other international standards); identifying actions to further prevent and reduce underwater noise from ships, including options to integrate new and advancing technologies and/or vessel design solutions taking into account geographical characteristics; considering the impact and interrelation of the proposed actions in the context of achieving other regulatory goals, including ship safety, energy efficiency, as well as the vision and mandate of the Organization to reduce pollution from ships; amending the 2014 Guidelines; considering ways to promote the work of the Organization to increase the awareness, the uptake and implementation of the Guidelines and identifying the most appropriate tools to do this; identifying areas that require further assessment and research; considering the next steps; maintaining and update a list of reports and documents provided in a submission to the Sub-Committee to produce a new Compendium on Underwater Noise from Commercial Shipping.

The work plan envisages that recommendations for the next steps to be undertaken to establish international solutions for the reduction of underwater noise could be submitted to the Marine Environment Protection Committee (MEPC 80) in 2023.

The Sub-Committee endorsed the Working Group's recommendation to invite all relevant IMO bodies to note the work on underwater radiated noise, in particular, where there are linkages, impacts or co-benefits.

The Sub-Committee was updated on a new project bid to the Global Environment Facility by the Secretariat's Department for Partnerships and Projects (DPP) to seek funding for a project ("Global Partnership for Mitigation of Underwater Noise from Shipping (GloNoise Partnership)"), with the overall objective to establish a global stakeholders' partnership, with a strong developing countries' focus, in order to deal with underwater noise from shipping.

New regulations and Code to address safety of industrial personnel agreed 

A new Code and requirements in the International Convention on the Safety of Life at Sea (SOLAS) to ensure the safety of people transported to work on offshore facilities were agreed.

The Sub-Committee finalized the draft texts of the new SOLAS chapter XV and the associated new Code for Industrial Personnel, both of which provide mandatory provisions for ships carrying industrial personnel to ensure the safety of such personnel on ships carrying them.

The draft texts will now be submitted to the Maritime Safety Committee (MSC) for approval and adoption, with a view to entry into force on 1 July 2024.

The aim is to provide mandatory minimum safety standards for ships that carry industrial personnel, as well as for the personnel themselves, addressing specific risks of maritime operations within the offshore sectors, such as personnel transfer operations. Such personnel may be engaged in the construction, maintenance, decommissioning, operation or servicing of offshore facilities, such as wind farms, as well as offshore oil and gas installations, aquaculture, ocean mining or similar activities.

Unified interpretations for noise levels on board ships agreed

The Sub-Committee agreed draft unified interpretations of SOLAS chapter II-1, the 1988 Load Lines Protocol and the Code on noise levels on board ships.

Draft Explanatory Notes to Interim guidelines on second generation intact stability criteria agreed

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 MSC (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.

Mandatory criteria and recommended provisions regarding intact stability are set out in IMO's 2008 Intact Stability (IS) Code, which is mandatory under chapter II-1 of the SOLAS Convention 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 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.

Draft amendments to the ESP Code finalized

The Sub-Committee finalized draft amendments to the International Code on the Enhanced Programme of Inspections during Surveys of Bulk Carriers and Oil Tankers, 2011 (ESP Code), intended to address safety issues that were identified during the flag Stateʹs marine safety investigation of the loss of MV Stella Daisy, by increasing the frequency of inspections of void spaces, based on the condition of hard coatings.

The draft amendments stipulate that void spaces should be inspected annually when the condition of coatings are less than GOOD (as determined in the ESP Code).

Performance standards for water level detectors revised

The Sub-Committee agreed to a draft revision of the Performance standards for water level detectors (resolution MSC.188(79)/Rev.1). The revision expands the application of the performance standards to water level detectors on multiple hold cargo ships other than bulk carriers and tankers as prescribed in new SOLAS regulation II-1/25-1, which is expected to enter into force on 1 January 2024 and will require the installation of such water level detectors.

The revision adds two new sections to the Performance standards with respect to the use of bilge alarms as water level detectors on multiple hold cargo ships for compliance with new SOLAS regulation II-1/25-1 and the periodic testing of water level detectors on board. It was agreed that the draft revised performance standards should apply to water level detectors installed on or after 1 January 2024.

Guidelines on alternative design and arrangements for SOLAS chapter II-1

SOLAS provisions allow the approval of alternative designs and arrangements, provided that they meet the intent of the requirements concerned and provide an equivalent level of safety. To support the development of new designs and alternative technology, IMO has been developing goals and functional requirements.

The Sub-Committee agreed, in principle, to the draft goal, functional requirements and expected performances for SOLAS chapter II-1, part D on electrical installations.

The draft goal for alternative designs and arrangements is: "To ensure adequate availability of electrically-powered services for safe operation of the ship and protect the persons on board from hazards of electrical origin in normal and emergency conditions."

In 2019, MSC approved Guidelines on alternative design and arrangements for SOLAS chapters II-1 and III (MSC.1/Circ.1212/Rev.1), outlining the methodology for the engineering analysis required by SOLAS regulations II-1/55 and III/38 on Alternative design and arrangements, applying to a specific engineering or life-saving system, design or arrangements for which the approval of an alternative design deviating from the prescriptive requirements of SOLAS chapters II-1 and III is sought.  

Prohibiting asbestos on mobile offshore drilling units

The Sub-Committee established a correspondence group to develop draft amendments to the Code for the Construction and Equipment of Mobile Offshore Drilling Units (MODU Code) (2009 MODU Code (resolution A.1023(26), as amended), the 1979 MODU Code (resolution А.414(XI), as amended) and the 1989 MODU Code (resolution А.649(16), as amended)) to prohibit the use of materials containing asbestos, including control of storage of such materials on board all MODUs.

This would align the MODU Code with the provisions of SOLAS regulation II-1/3-5.