The Navigation marks used worldwide can be split into a number of groups;

  1. Region A Channel Markers
  2. Region B Channel Markers
  3. Cardinal Marks
  4. Isolated Danger Marker
  5. Special Markers
  6. Fairway Markers / Safe Water Markers
  7. Emergency Wreck Mark

Each of the navigation marks can be individually identified by 3 features;

  1. Top Mark
  2. Light sequence (if lit)
  3. Colour

Region A – Channel Markers.

The group is made of 2 marks – Port Cans and Starboard Cones. When entering a channel, harbour or river, you will be going with the direction of buoyage which means as you enter the harbour you should keep the Green ‘starboard’ markers on the starboard side of the boat and the Red ‘Port’ Markers on the port side of the boat. Within this group of navigation marks, preferred channel markers can also be found. These indicate a better lit, marked channel inside a harbour. These have a ‘coloured band’ in the middle of the marker which says which way is the preferred channel.

Region B – Channel Markers

IALA ‘B’ or Region ‘B’ Markers are only found in a few countries around the world which include USA, Canada, Japan and the Philippines. The only difference between Region A & B is the colour of the marker. This means that entering a harbour in Region B, the starboard markers are Red.

Cardinal Marks

A cardinal mark used in maritime pilotage to indicate the position of a hazard and the direction of safe water. They are used to indicate the direction of safety as a cardinal (compass) direction (north, east, south or west) relative to the mark. An example of this group is the North Cardinal Marker which is used to indicate that safe water is too the North of where the marker is located.

North Cardinal:

    • Top Mark: 2 triangles pointing up
    • Flashing Sequence: Quick or Continuous Flashing Light
    • Light: White
    • Colour: Black/Yellow
  • East Cardinal:
    • Top Mark: 2 triangles pointing away from each other
    • Flashing Sequence: Q 3 Flashes every 10 seconds
    • Light: White
    • Colour: Black/Yellow/Black
  • South Cardinal:
    • Top Mark: 2 triangles pointing down
    • Flashing Sequence: Quick 6 & 1 Long Flash every 15 seconds.
    • Light: White
    • Colour: Yellow/Black
  • West Cardinal:
    • Top Mark: 2 triangles pointing towards each other
    • Flashing Sequence: Quick 9 Flashes every 15 seconds.
    • Light: White
    • Colour: Yellow/Black/Yellow

Isolated Danger Marks

This marker is different from the cardinal marks above because it marks the spot where the danger is. There is safe water all around the navigation mark and can be identified at night because of its 2 white flashes. A great way to remember the flashing sequence is to think of the mark saying ‘Go Away’.

Special Marker

These markers come in all shapes and sizes and are not generally navigation marks. They are used extensively in marking Fish Farms, cables, outfall pipes, transits and occasionally are found where a channel splits into 2. They have an equally vague light sequence when lit which is a sequence that is not used by any other mark in the immediate area.

Fairway or Safe Water Mark

This is the same marker with the same top mark and colour but it serves 2 different purposes. The fairway markers purpose is to mark the start, middle and occasionally the end of the fairway or channel essentially acting as the central reservation. Fairway markers are generally 3 meters tall to enable them to be spotted by large ships. Safe water marks are generally located at the entrances to marinas like Largs Yacht Haven, or a channel and if approaching the marina or channel the Safe Water Mark would indicate that you are leaving safe water and should navigate with caution. There are 4 possible light sequences on these marks; Isophase, Occulting, Morse A and a Long Flash.

Emergency Wreck Marker:

It is used to warn of a new wreck which has not yet been listed in maritime documents. The buoy is expected to be deployed for the first 24-72 hours after the wreck occurs. After that time more permanent buoyage such as isolated danger marks or cardinal marks should be deployed 

The buoy is designed to “provide a clear and unambiguous mark of a new and uncharted danger. In addition it may have the word “WRECK” painted on it. Optionally it may carry a vertical cross painted yellow. The light flashes alternate yellow and blue for one second each with a half second gap between. 

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