Lateral and Preferred Channel Marks

• Use the charted conventional direction of buoyage to identify Region A port- and starboard-hand marks and state what each mark defines without turning it into an automatic helm order.
• Combine body colour, shape or topmark, light colour, complete rhythm and charted position to distinguish an ordinary Region A lateral mark from a preferred-channel mark.
• Separate a lateral mark's channel-side meaning from the depth, clearance, traffic and route evidence needed for a vessel-specific pilotage decision.

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