Communications about port restrictions inevitably use abbreviations or expressions, which should be clearly understood. Some of the most common are:
LOA (Length Overall): the actual length of the vessel that will be able to enter the port, berth or discharging place. In some cases the vessel will not be able to enter the port because of its length which may be due to meandering rivers, e.g. Rouen, or lack of berth length, e.g. Alexandria (620′ LOA max.).
Beam: The actual beam of the vessel that may be important should there be a lock or a channel through which the vessel has to pass in order to get to the discharging/loading berth (e.g. Avonmouth where the berths are through a lock). The beam of the vessel may also be important at the cargo installation where the outreach of the loading/discharging gear may be a limiting factor. Often shipowners are requested to give additional information about the vessel such as the distance between ship’s rail (side) and the hatch coaming (side of hatch). This is usually for the purpose of checking if the shore cargo installation can reach into the hold of the vessel.
Draft: If no draft restriction is stipulated and the discharge port is named in the charter party it is the owners’ responsibility to ensure that the vessel can meet the draft restrictions at that port. If, however, she is only fixed to a range of discharge ports, the responsibility remains with the charterers who will need to know the arrival draft of the vessel before they can nominate a safe berth. The charterer may also require more information about the vessel, such as the height from the waterline to the top of the hatch coaming in fully ballasted condition; this will be in order to ensure that the vessel can remain beneath the shore facilities during the entire loading/discharging operation.
Airdraft: Occasionally the term used to describe the distance from a vessel’s waterline to the top of hatch-coamings. Otherwise, this is the distance between the waterline and the highest fixed point on the vessel (usually the radar mast, although this may be hinged) in fully ballasted condition. This is usually required when, for example, an empty, ballasted vessel is to load in a berth where, in order to reach the berth, she must pass under a bridge (e.g. Toledo in Lake Erie). Alternatively, it can be required in a different set of circumstances such as in Genoa where there is an airport close to the berths and the port authority restricts the air draft of vessels to a certain height so as not to interfere with the approach path of an aircraft.
SWAD: This means “Salt Water Arrival Draft” and is the maximum draft that a vessel, in a loaded condition should draw upon arrival at a port of discharge (variable according to the port).
FWAD: “Fresh Water Arrival Draft” – as with salt water but, instead of the sea, usually applies to places on rivers (e.g. Warri 21′ FWAD and Matadi 22′ FWAD in West Africa).
Bar Draft: Where river silt builds up, “bars” are often formed so vessels will be required to load up-river to a draft able to pass safely over the bar to “top-off” in other ports (e.g. Martin Garcia Bar where vessels load up River Parana toping-off at Buenos Aires, similarly loading in Bangkok, completing Kosichang).
In some ports, there are several sets of circumstances which owners must consider. For example in Buenaventura (Colombia), there is basically one wharf/berth which is divided into imports and exports. The depth of water at low tide is 24′ and consequently charterers of the ship and/or receivers of the cargo always need vessel to agree NAABSA terms. An additional problem at Buenaventura is that there is a bar at the entrance to the port and this can only be crossed by vessels drawing maximum 28′, one hour before to one hour after high tide. Apart from such physical restrictions of LOA, BEAM etc. there are other restrictions which may cause a shipowner to reconsider calling at a port e.g. weather conditions, including ice, which will be discussed later in this section, and which may cause restrictions on entry at certain times of the year. War zones or war areas naturally cause owners first to consider the safety of their ship and crew and secondly, the extra insurance premiums which are payable whilst in war zones.