Buoys that represent the sides of a channel primarily use light characteristics to communicate their significance to mariners. These characteristics help mariners identify which side of the channel they are approaching or navigating through.
Flashers such as flashing, quick flashing, and isophase are all used to indicate side-buoys. Flashing lights, which include rapid on-off sequences, help convey positional information, and quick flashing lights indicate a higher frequency of flashes per minute, offering a different visual cue. Isophase lights are characterized by equal durations of light and dark, providing a steady and consistent signal.
Composite group flashing, however, incorporates multiple flashes in a specific sequence and is more complex in its signaling. This characteristic is typically associated with marks that convey more intricate information about the navigation structure rather than simple channel indication. As such, buoys that solely identify the sides of a channel do not utilize this light characteristic.
This differentiation ensures that mariners can easily perceive and react to channel markers without the added complexity of more elaborate signaling systems.