IALA buoyage System
Marks are distinguished by their colour, being red or green, and shape.For historical reasons, two different schemes are in use worldwide, differing in their use of colour.
Previously there had been 30 different buoyage systems, prior to IALA introducing the rationalised system. In 1980 on a conference convened by IALA, they agreed to adopt the rules of a new combined system, which combined the previous two systems (A and B) into one system, with two regions (A and B).
Previously there had been 30 different buoyage systems, prior to IALA introducing the rationalised system. In 1980 on a conference convened by IALA, they agreed to adopt the rules of a new combined system, which combined the previous two systems (A and B) into one system, with two regions (A and B).
The IALA defines them as Region A and Region B:
- Region A comprises nations in Europe, Australia, New Zealand, parts of Africa and most ofAsia other than the Philippines, Japan and Korea.
- Region B comprises nations in North America, Central America and South America, thePhilippines, Japan and Korea.
Region A
- port marks are red and may have a red flashing light of any rhythm.
- starboard marks are green and may have a green flashing light of any rhythm.
Region B
- port marks are green and may have a green flashing light of any rhythm.
- starboard marks are red and may have a red flashing light of any rhythm.
Both regions
- port marks are square or have a flat top
- starboard marks are conical (or present a triangular shape) or have a pointed top.
The shape is an important feature, as colours cannot be distinguished in some light conditions, or by persons with red-green colour blindness. Marks may also carry unique markings of letters and numbers; these may be used to identify the mark as one indicated on anautical chart. Likewise, a mark’s light may flash in a distinctive sequence for the same purpose.Also defined in the lateral mark systems is a bifurcation mark, which has both red and green horizontal bands, one over the other. This mark indicates that a “preferred” channel (often, a deep channel suitable for heavy commercial traffic) lies to one side, and a secondary channel on the other. Vessels wishing to use the preferred channel observe the top colour of the mark, and vessels wishing to use the secondary channel observe the bottom colour.
In Region A only, the phrase “Is there any red port left?” (referring to the red colour of the fortified wine “port”) may be used as a mnemonic, indicating that a red mark must be kept on the left when “returning” to (i.e, entering) a harbour or river.
In Region B only, the phrase “red right returning” may be used as a mnemonic, indicating that a red mark must be kept on the right whenreturning to (i.e., entering) a harbour or river.
cardinal mark
A cardinal mark is a sea mark (a buoy or other floating or fixed structure) used in maritime pilotage to indicate the position of a hazard and the direction of safe water.
Cardinal marks indicate the direction of safety as a cardinal (compass) direction (north, east, south or west) relative to the mark. This makes them meaningful regardless of the direction or position of the approaching vessel, in contrast to the (perhaps better-known) lateral mark system.
The characteristics and meanings of cardinal marks are as defined by theInternational Association of Lighthouse Authorities.
North cardinal mark
Has two cones pointing up – Pass on the northern side of this mark.
East cardinal mark
Has two cones pointing away from each other – Pass on the eastern side of this mark.South cardinal mark
Has two cones pointing down – Pass on the southern side of this mark.West cardinal mark
Has two cones point to point – Pass on the western side of this mark.
A cardinal mark indicates one of the four compass directions by:
- the direction of its two conical top-marks, which can both point up, indicating north; down, indicating south; towards each other, indicating west; or away from each other, indicating east
- its distinctive pattern of black and yellow stripes, which follows the orientation of the cones – the black stripe is in the position pointed to by the cones (eg at the top for a north cardinal, in the middle for a west cardinal)
- optionally, its distinctive sequence of flashing light, which consists of a sequence of quick or very quick flashes whose number gives the clockface position which corresponds to the direction of the cardinal (eg three for an east cardinal, nine for a west; north has continuous flashes, and south may be augmented with a long flash, to help distinguish it from a west in difficult conditions)
The topmark configurations for north and south are self-explanatory (both cones pointing up, or both pointing down). Those for east and west “follow the Sun”—the top cone points in the direction in which the rising (for an east mark) or setting (for a west mark) Sun appears to move with respect to the horizon, while the bottom cone points in the direction in which its reflection on the ocean surface appears to move. (An alternative memory aid is to see cones pointing inwards as a waist (“west”), and cones pointing out forming an egg (“east”).
In the diagram, the light sequence is indicated by the white-banded pattern and the notation Q (forquick) or VQ (very quick). Either the quick or the very quick sequence may be used; the choice allows for two similar nearby marks to be uniquely identified by their lights.
A cardinal mark may be used to accomplish the following:
- Indicate that the deepest water is an area on the named side of the mark
- Indicate the safe side on which to pass a danger
- Draw attention to a feature in a channel, such as a bend, junction, branch, or end of a shoal
- Draw attention to a new danger such as a grounded ship. In such cases two equal marks are often placed together to indicate that it’s a newly marked danger and is not yet printed in official maps.
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