CHAPTER 6 Operational Planning
Change A 6-23
Figure 6-12. International Code Signal Flags.
IN: I require a diver.
IO: I have no diver.
IN1: I require a diver to clear my propeller.
IP: A diver will be sent as soon as pos-
sible or at time indicated.
IN2: I require a diver to examine bottom.
IQ: Diver has been attacked by divers
disease and requires decompression
IN3: I require a diver to place collision mat.
IR: I am engaged in submarine survey
work (underwater operations). Keep
clear of me and go slow.
IN4: I require a diver to clear my anchor.
A: I have a diver down; Keep well clear at
Code Flag (Note 1)
Sport Diver (Unofficial)
General Note: Rule 27 of Navigation Rules-International -Inland of December 1983 states the lights
and shapes that must be displayed when engaged in diving operations.
Note 1: International Signal Code All signals must be preceded by the code flag to signify that they
are international signals. (Do not use code flag in inland waters.)