On the 18th and 19th of September, IMO held an expert workshop to consider the interrelationship between the energy efficiency measures and reduction of Underwater Radiated Noise (URN). In advance of the workshop, Transport Canada sponsored the consultant VARD to do a comprehensive review of the energy efficiency measures and to predict their impact on URN. A summary and full copy of the VARD report is attached and its appendix includes over a hundred measures. It provides predictions of the approximate efficiency gains (%) and the URN reductions (decibels). The report will be further updated by VARD to reflect the workshop discussions and submitted to SDC in January 2024. Therefore, please regard this copy as a draft. Nevertheless, for ship owners considering energy efficiency measures, it can form a useful starting point for selection of measures that both ensure GHG regulatory compliance and URN reduction. ICS recommends that Ship owners should also carry out their own due diligence and assessment of any short-listed measures prior to contracting for equipment or services.

The ICS will forward later versions of the VARD report as and when they become available.

Any queries or comments on this document should be addressed to Chris Waddington, Technical Director at – chris.waddington@ics-shipping.org.

Underwater Noise abatment.

MC(23)87 -Annex A – VARD Report