Purpose. To indicate to the mariner a special area or feature the nature of which is apparent from reference to a chart, sailing directions or notices to mariners. Special marks may be lettered to indicate their purpose. Uses include the following: ODAS (Ocean Data Acquisition System) buoys. Traffic separation schemes…
Purpose. Safe water marks are used to indicate that there is navigable water all round the mark. It could be used as a centre line, mid-channel or land fall buoy, or to indicate the best point of passage under a bridge. Colours. Red with white vertical stripes are used for…
Purpose. Isolated danger marks are erected on or moored on or above isolated dangers of limited extent which have navigable water all round them. On Admiralty charts the position of the danger is the centre of the symbol or sounding indicating the danger. Top mark. Black double sphere top marks…
Cardinal marks are used together with the compass to indicate where the mariner may find the best navigable water. They are placed in one of the four quadrants (North, south, east or west), boundered by inter-cardinal bearings. The mariner is safe if he passes north of a North cardinal mark,…
Purpose. Lateral marks are used for well defined channels in conjunction with the general direction of buoyage. They indicate the port and starboard hand sides of the route to be followed. Direction of buoyage. The conventional direction of buoyage is defined in one of two ways: Local direction of buoyage.…
Application and purpose. The system applies to all fixed and floating marks, other than lighthouses, sectors of lights, leading lights and marks, lanbys, certain large light floats and light vessels. Its purpose is to indicate: The sides and centrelines of navigable channels; Navigable channels under fixed bridges; Natural dangers and…
