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Buoys, Beacons

IALA Maritime Buoyage System

  IALA  International Association of Lighthouse Authorities

Where in force, the IALA System applies to all fixed and floating marks except lighthouses, sector lights, leading lights and leading marks, light-vessels and lanbys. The standard buoy shapes are cylindrical (can), conical, spherical, pillar and spar. Variations may occur; for example, light-floats. (See Buoy Shapes and Types for examples.) In the illustrations below, only the standard buoy shapes are used. In the case of fixed beacons (lit or unlit), only the shape of the topmark is of navigational significance.

Lateral Marks are generally for well-defined channels. There are two international Buoyage Regions, A and B, where Lateral marks differ.

IALA Buoyage Regions A and B
click for larger image
A preferred channel buoy may also be a pillar or a spar. All preferred channel marks have horizontal bands of color. Where for exceptional reasons an Authority considers that a green color for buoys is not satisfactory, black may be used.

Direction of Buoyage
The direction of buoyage is that taken when approaching a harbor from seaward or along coasts, the direction determined by buoyage authorities (normally clockwise around land masses).
click for larger image Symbol showing direction of buoyage where not obvious.
click for larger image Symbol showing direction of buoyage on multicolored charts.