What does a safe water mark mean?
Navigable water all around it. You'll often find one at a harbour approach or mid-channel.
It's the only IALA mark with vertical stripes, so it's easy to pick out. You can pass either side.
- Colour: red and white vertical stripes.
- Topmark (if any): a single red ball.
- Light (if any): white, isophase, occulting, one long flash every 10 seconds, or Morse A.
Source: IALA Maritime Buoyage System, safe water marks.
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In IALA Region A, what colour and shape is a port-hand mark?
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