Part B - Lateral Marks

Jeff Watts

Lateral marks

These show the outer limits of safe channels that must be followed.

In IALA Region 'A', you must keep the starboard mark on the starboard side of your vessel when traveling into a port. It marks the starboard limit of deep water.

Remember 'Green to Green going Upstream'. Try to visualise a port or starboard mark in a familiar situation and use this to remember which side the shallow water is on.

Starboard hand lateral mark

Feature	Colour
Buoyage shape	Conical or triangular buoy or a pillar
Buoyage colour	Green
Topmark shape	Triangular
Topmark colour	Green
Light rhythm	Any rhythm
Light colour	Green

Port hand lateral mark

Feature	Colour
Buoyage shape	Square or 'can shaped' buoy or a pillar
Buoyage colour	Red
Topmark shape	Square
Topmark colour	Red
Light rhythm	Any rhythm
Light colour	Red

Preferred channel markers

These are like lateral marks, but show the deepest or preferred channel if there are a couple to choose from. The dominant colour will show to way to the preferred channel, and the small stripe will show the way to the smaller channel. Think of the light rhythm as showing a combination of a big and small channel (2 + 1)

Starboard hand preferred channel mark

Feature	Colour
Buoyage shape	Conical or triangular buoy or a pillar
Buoyage colour	Green with a red band
Topmark shape	Cone
Topmark colour	Green
Light rhythm	Composite group flash (2+1)
Light colour	Green

Port hand preferred channel mark

Feature	Colour
Buoyage shape	Square or 'can shaped' buoy or a pillar
Buoyage colour	Red with a green band
Topmark shape	Square
Topmark colour	Red
Light rhythm	Composite group flash (2+1)
Light colour	Red

Click here to see how these buoys are used.