Marine Advisory: 40/2024 - Corrosion of lifeboat self-contained air support system cylinders

26 December 2024

Marine Advisory: 40/2024

SUBJECT: Underwater Noise

Ref: (a) MEPC.1/Circ.906/Rev.1

Dear Shipowners/Operators/Masters/Recognized Organizations:

Purpose

The purpose of this Advisory is to provide guidance to all Shipowners, Operators, Masters, and Recognized Organizations on the reduction of underwater noise from commercial shipping.

Background

The Marine Environment Protection Committee, at its eighty-second session approved the amendments pertaining to the Revised guidelines for the reduction of underwater radiated noise (URN) from shipping to address adverse impacts on marine life.

Commercial shipping significantly contributes to underwater radiated noise (URN), which negatively impacts marine life, including mammals, fish, and invertebrates, essential to coastal indigenous communities. Effective URN mitigation requires international collaboration among various stakeholders such as seafarers, shipbuilders, operators, maritime authorities, and Member States, which play a key role in setting noise reduction targets and mechanisms.

For both new and existing ships, URN reduction measures depend on the ship's design, operational parameters, and cost-effectiveness. A comprehensive URN reduction strategy involves incorporating noise mitigation during the design stage, establishing baseline URN measurements, setting reduction targets, and implementing and assessing technical and operational measures. Additionally, these efforts should balance other objectives, including energy efficiency, biofouling control, and ship safety.

Guidance

Revised Guidelines for the Reduction of Underwater Radiated Noise from Shipping to Address Adverse Impacts on Marine Life, MEPC.1/Circ.906/Rev.1, addresses URN management and planning. It also provides details about the relationship between the Energy Efficiency Compliance Measures and URN.

Many of the energy efficiency improvement options to meet energy efficiency regulations (EEDI, EEXI

and CII) may result in an improvement in URN performance. There is also information provided on URN reduction approach based on design, technical, operational and maintenance aspects.

All shipowners and stakeholders are encouraged to use URN reduction management planning as a tool that may be applied to the operation, design, construction and modification of ships and to share the experience and information obtained from ship and equipment designers, shipbuilders, operators, and other stakeholders.

For more information, please contact the Regulations and Standards Department at RegsandStandards@liscr.com or telephone +1 703 790 3434.

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