Liquefied gas shipping has a very impressive, in fact unprecedented, safety record for the loading, carriage and delivery of liquid hydrocarbons by sea in bulk. Surge events occur very infrequently due to the consideration given to the liquefied gas transfer system, using guidance and standards such as this publication. Specialists skilled and experienced in the analysis of these transfer systems are required to analyse the systems during the design phase of a project. System operators should also be aware of the recommendations and guidelines contained within to protect against surge events.

Surge pressures can lead to very high stressing of pipelines and equipment, with possible outcomes of physical damage and/or loss of containment. The purpose of this document is to provide familiarisation with the concepts of surge pressure and to provide practical guidance and recommendations to the designers, engineers and operators of both liquefied gas carriers and terminal loading and unloading systems. This knowledge and familiarity are intended to assist them to: