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General Guide For Most Paper Charts

White is indicated as deep water, blue indicates shallower the water.

Grey or a solid beige indicates land masses.

A muted or light blue/green indicates a marsh or inter-tidal zone.

Symbols featured below.

• Buoys and day-marks. Color, Shape, Number, Lights.

The shape is marked as the chart symbol as well as the color code GR – Green and R – Red. The number usually corresponds to the flashing pattern of lighted buoys.

•  IALA system A and B

IALA is the International Association of Marine Aids to Navigation and Lighthouse Authorities, in 1970s this body was developed to drastically decrease the amount of buoyage systems in the world down to around 30, to two at the start of the 80s deemed IALA A and IALA B. 

IALA A dictates the system for Africa, most of Asia, Australia, Europe and India. In this system the port marks and lights are colored red whilst the starboard are colored green.

 IALA B is for the Americas, Japan, Korea and the Philippines. In this system, port is colored green whilst starboard is colored red.

• Distance measurements

Distance on Charts are measured in nautical miles 1 nautical mile being about 1.15 land miles. The charts may also be measured in minutes over latitude / longitude lines. 1 minute being 1 nautical mile.

• Compass rose

The compass rose helps in orient the map by offering a stationary bearing of north with reference to map items, allowing you to take bearings properly. It also shows the difference between magnetic and true north at the position of the chart.