68
Mark Description
Rhythm
Port Hand & Starboard
Marks:
Any, other than Composite Group Flashing (2+1)
Preferred Channel
Starboard:
Composite Group Flashing (2+1)
Preferred Channel Port: Composite Group Flashing (2+1)
North Cardinal Mark:
Very quick or quick
East Cardinal Mark:
Very quick (3) every 5 seconds or quick (3) every 10 seconds
South Cardinal Mark:
Very quick (6) + long flash every 10 seconds or quick (6) + long
flash every 15 seconds
West Cardinal Mark:
Very quick (9) every 10 seconds or quick (9) every 15 seconds
Isolated Danger Mark:
Group flashing (2)
Safe Water Mark:
Isophase, occulting, one long flash every 10 seconds or Morse
Code “A”
Special Marks:
Any, other than those described for Cardinal, Isolated Danger
or Safe Water Marks
Recommended Rhythm for Flashing Light - IALA Regions A and B