RADIO AIDS TO MARINE NAVIGATION - Canadian Coast Guard

Operation guidance for masters of ships observing another vessel apparently in danger
7. The following diagram shows suggested procedures for reporting concerns about the safety of another vessel (fire,
smoke, adrift, navigating towards a danger, etc.).
Try to communicate.
Response received ?
Yes
Inform the other ship
about your concern and
try to obtain further
information.
Are you satisfied?
Yes
After verifying that
assistance is not
required, proceed on
passage.
No
No
Try to obtain the
maximum of information
about the other vessel
(name, C/S, type,
position, course, speed)
and inform the JRCC
Sometimes the master of
a vessel in distress does
not immediately contact
the JRCC
Try to keep track of the
reported vessel (radar,
visual and comm's),
unless otherwise directed
by JRCC
Note: For local JRCC contact information, refer to section SEARCH AND RESCUE IN CANADIAN AREAS OF
RESPONSIBILITY (Part 4 of this publication).
False Distress Alerts and Distress Relay Alerts
The GMDSS has been in force for ships on international voyages since February 1, 1999, following its seven-year phasein.
During this time, considerable experience was gained internationally in the operation of the GMDSS. While the
GMDSS has proven its overall effectiveness, the high number of accidental distress alert activations and the inappropriate
and unintended Digital Selective Calling (DSC) distress relay alerts have detracted from the efficiency of the system.
Excessive false alerts and distress relay alerts can create an unnecessary burden and workload for SAR services. They may
also cause confusion and undermine mariner’s confidence in the GMDSS. They could potentially have a serious impact on
real distress situations.
With the aim of minimizing the number of false alerts and distress alert relays, the following information is provided:
• “Instructions for Mariners and Others on How to Cancel a False Alert” (appendix to IMO Resolution A.814(19)
entitled Guidelines for the Avoidance of False Distress Alerts);
• “Procedure for Responding to DSC Distress Alerts by Ships” (COMSAR/Cir.21).
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