IALA Special Marks

Yellow marks indicating special areas such as ODAS, traffic separation, military exercise areas, or cables/pipelines.

Special marks indicate a special area or feature referred to in nautical publications. They are not primarily intended to assist navigation.

- Colour: yellow - Topmark: single yellow X-shape (St. Andrew's cross) - Light: yellow, any rhythm not used for other marks - Shape: optional — any shape not conflicting with lateral or safe water marks

Examples include: ocean data acquisition systems (ODAS), traffic separation marks, spoil ground marks, military exercise zone marks, cable or pipeline marks, recreation zone marks.

Puntos Clave

All yellow colour scheme

X-shaped (cross) topmark in yellow

Yellow light distinguishes from navigation marks

Indicates special areas — check nautical publications for details

Errores Frecuentes

Assuming special marks indicate a navigational hazard

Not consulting charts/publications for what the mark indicates

Pon a Prueba tus Conocimientos

Test your knowledge and prove your mastery.