A merican Club Circular No . 2 1/22 1 AUGUST 8, 2022 CIRCULAR NO. 21/22 TO MEMBERS OF THE ASSOCIATION Dear Member: LOSS PREVENTION: ROLL RISK ESTIMATOR FOR CONTAINER SHIPS The International Group (IG) is a member of the Maritime Research Institute of the Netherlands (MARIN) Top Tier project. The project has been established to examine and assess the causes of container losses arising from at-sea incidents onboard various sizes of container ships with a particular focus on ultra-large ships. The project has been approved by a cross-section of industry, academic and government interests and MARIN will produce a report of its findings including recommendations in due course. It is envisaged that the recommendations will eventually lead to operational and technical improvements that should mitigate the risk and underlying causes of container losses at sea. The IG has received the latest version of roll risk estimator. It indicates combinations of speed, heading and wave period that result in unfavorable tuning of roll motions that should be avoided. It does not give indications of the maximum roll motion, and at which wave height the vessel is vulnerable to adverse rolling. These must be judged by the reference to the master’s experience. In addition, it does not address other dangerous ship behavior such as large vertical accelerations, shipping green water and slamming. Yours faithfully, Dorothea Ioannou, CEO Shipowners Claims Bureau, Inc., Managers for THE AMERICAN CLUB All clubs in the International Group have issued similar circulars.