Customary. This word usually refers to the rate at which cargo operations are to take place and may affect the time the vessel is made available by the owner for these operations.
For example, “customary despatch” means that the charterer must ensure that cargo operations are carried as fast as is possible in the circumstances prevailing at the time of loading or discharging. The use of words such as “customary” can make the counting of laytime quite uncertain. The uncertainty is not improved by using other, similar phrases such as that the cargo is to be discharged “ . . . as fast as the vessel can deliver in accordance with the custom of the port . . .” (“C.O.P.”). The reference to “custom” means a settled and established practice in the port. The practice is more relevant to the manner in which the cargo operations are to be carried out and not exclusively to the time these would use. The custom or working practices in the port would be a contributory component of the total time available for cargo operations. The time would be “reasonable” and this would take into account all the circumstances of which “custom” is one.
If an indefinite time for cargo operations is qualified or partly defined by express reference to “customary despatch” or “custom of the port” every restriction arising from that custom or practice should be taken into consideration if these occur for external factors and the Charterer cannot overcome them by the use of reasonable diligence. Therefore the Charterer will not be liable for demurrage or delay if this is caused by port practice he could not foresee. Circumstances that could affect customary practice and the speed of (and time taken for) cargo operations are, for example, strikes, action of harbour authorities, limits imposed by cargo-handling equipment on board the vessel and unforeseeable difficulties imposed on shippers and/or receivers.
