Five types of mark are provided by the System
1) Lateral
2) Cardinal
3) Isolated Danger
4) Safe water
5) Special marks
They maybe used in any combination..
Most lighted and unlighted beacons,other than leading marks, are included in the System. In general,beacon topmarks have the same shapes and colours as those used on buoys, (Because of tje variety of beacon structures, the accompanying diagrams show mainly buoy shapes )
Wrecks are marked in the same way as other dangers; on unique types of mark is reserved for them in the IALA System.
Colours of buoys
Red and green are reserved for Lateral marks, and yellow for Special marks, Black and yellow or black and red bands,or red and white stripes are used for other types of marks as described later.
On Admiralty charts, the shading of buoy symbols formerly used to indicate the colours of buoys is omitted. A black (ie filled-in) symbol is used for predominantly green marks and for all spar buoys and beacons; and open symbol is used for all buoys and beacon towers of other colours, but with a vertical line to indicate striped Safe Water buoys.
The abbreviated description of the colour, or colours, of a buoy is given under the symbol.
Where a buoy is coloured in bands, the colours are indicated in sequence from the top, eg East buoy Black with a yellow band BYB. If the sequence of the bands is not known, or if the buoy is striped, the colours are indicated with the darker colour first eg Safe Water buoy Red and white stripes RW.
Shapes of Buoys
Five basic shapes were defined when the System was devised: Can, Conical, Spherical, Pillar and Spar.
But to these must be added light-floats, as well as buoyant beacons (which are charted as light-beacons).
Variations in the basic shapes may be common for a number of years after the introduction of the IALA System to a particular locality since much existing equipment will continue in use.
Can, conical and spherical buoys indicate by their shape the correct side to pass.
Marks that do not rely on their shape for identification, carry the appropriate topmark whenever practicable. However, in some parts of the world, including US waters, light-buoys have identical shapes on both port and starboard sides of Laterally-marked channels, and are fitted with topmarks. Also in US waters, a buoy w conical or truncated conical top, known as a nun bud used to mark the starboard side of the channel.
On Admiralty charts, if the shape of a buoy of the IALA System is not known, a pillar buoy is used.
The symbol for a spar buoy is also used to indicate a spindle buoy. The symbol will, as before, be sloped to distinguish it from a beacon symbol which is upright.
Topmarks
Can, conical, spherical and X-shaped topmarks only are used.
On pillar and spar buoys the use of topmarks is particularly important, though ice or severe weather may at times prevent it.
On Admiralty charts, topmarks are shown boldly, in solid black except when the topmark is red, when it is in outline only.
Lights
Red and green lights of the IALA System are reserved for Lateral marks and yellow lights for Special marks.
White lights, distinguished one from another by their rhythm, are used for other types of marks.
It is possible that some shore lights, specifically excluded from the IALA System, may, by coincidence have similar characteristics to those of the buoyage system. Care is needed on sighting such lights that they are not misinterpreted.
I will come back to you in the future with a number of separate articles on Buoys and an in-depth study of them. Have a nice day until then.Don't forget to leave your comments below
Good article
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