Canadian Coast Guard

SYSTEMS

GMDSS - GLOBAL MARITIME DISTRESS AND SAFETY SYSTEM IN CANADA

What is GMDSS?

The Global Maritime Distress and Safety System (GMDSS) is an international system using improved terrestrial and satellite technology and ship-board radio systems. It ensures rapid alerting of shore-based rescue and communications authorities in the event of an emergency. In addition, the system alerts vessels in the immediate vicinity and provides improved means of locating survivors.

GMDSS was developed through the International Maritime Organization (IMO) and represents a significant change in the way maritime safety communications are conducted. While it is mandatory for all ships subject to the International Convention for the Safety Of Life At Sea (SOLAS) (cargo ships 300 gross tons or greater and all passenger vessels, on international voyages), GMDSS will impact on all radio-equipped vessels, regardless of size. All SOLAS ships are required to fully comply with GMDSS.

Why GMDSS?

GMDSS was developed to SAVE LIVES by modernizing and enhancing the current radiocommunications system. By utilizing satellite and digital selective calling technology, GMDSS provides a more effective distress alerting system. It improves the current system by:

increasing the probability that an alert will be sent when a vessel is in distress;

increasing the likelihood that the alert will be received;

increasing the ability to locate survivors;

improving rescue communications and coordination; and

providing mariners with vital maritime safety information.

Maritime Safety Information (MSI)

Maritime Safety Information broadcasts, which comprise distress alerts, SAR information, navigational and weather warnings, as well as forecasts, can be received in three different ways in GMDSS:

NAVTEX receivers are fully automatic and receive broadcasts in coastal regions up to 300 nautical miles offshore.

Inmarsat-C terminals receive Enhanced Group Call - SafetyNET (EGC) broadcasts for areas outside NAVTEX coverage.

HF Narrow Band Direct Printing (NBDP) receivers can be used where service is available as an alternate to EGC.

GMDSS Sea Areas - International

Although ship-to-ship alerting is still an important function in GMDSS, the emphasis is on two way communications between ships and shore facilities. All GMDSS ships must be capable of communicating with the shore and transmitting a distress alert by two different means. The equipment carried by a GMDSS ship is therefore determined by its area of operation and the availability of shore-based communications services.

There are four “Sea Areas” defined in the GMDSS:

Sea Area A1Within range of shore-based VHF/DSC coast station (40 nautical miles)

Sea Area A2Within range of shore-based MF/DSC coast station (excluding sea areas A1)(150 nautical miles)

Sea Area A3Within the coverage of an Inmarsat geostationary satellite (approximately 70°N to 70°S)

(excluding sea areas A1 & A2)

Sea Area A4The remaining areas outside sea areas A1, A2 & A3 (polar regions)

GMDSS Sea Areas - Canada

In Canada, as a result of consultations with the Canadian marine industry, it has been decided to implement sea areas A1 on the east and west coasts. Outside of A1 will be an A3 sea area with an A4 sea area in the Arctic.

Consideration was given to the implementation of an A2 sea area, but due to budgetary constraints and the marine industry’s preference for sea areas A1 and A3, sea area A2 is not being planned at this time.

Communications between GMDSS Vessels & Non-GMDSS Vessels

Since February 1, 1999, GMDSS larger ships have been maintaining an automated listening watch on GMDSS VHF/DSC Ch 70 and MF/DSC 2187.5 kHz. This at times creates the situation, where vessels fitted with traditional, non-GMDSS radio equipment, may have had difficulties alerting or contacting a GMDSS ship. The Coast Guard is addressing this by monitoring both GMDSS and traditional distress frequencies. Canadian Coast Guard MCTS Centres will continue to monitor 2182 kHz and CH 16 for distress, urgency, safety and calling purposes for the foreseeable future. Further, the Coast Guard and Transport Canada encourage all vessels to fit VHF/DSC in the interest of increases safety.

Important Safety Notice concerning VHF/DSC

After having received a distress, urgency or safety broadcast announcement on VHF/DSC Channel 70 the VHF/DSC equipment will automatically switch the DSC radio to VHF Channel 16 for the subsequent voice announcements. Mariners who are required by the VHF Practices and Procedures Regulations to monitor a specific VTS sector frequency should return the radio to the appropriate working frequency after determining, on Channel 16, the impact of the VHF/DSC alert broadcast announcement on their vessel's’ operations.

It has been determined that vessels maintaining a listening watch on a VTS sector frequency, per the requirements of the VTS Zones Regulations may, if navigating in congested waters, temporarily discontinue DSC watchkeeping on VHF/DSC Channel 70 until the required maneuver has been completed.

Vessels inadvertently or accidentally transmitting a distress/urgency/safety broadcast on VHF/DSC must cancel the distress/urgency/safety broadcast on VHF Channel 16. Intentionally sending a false distress alert carries penalties under both the Canada Shipping Act and the Radiocommunications Act.

VHF/DSC equipment must be programmed with the correct Maritime Mobile Service Identity (MMSI) numbers (reference Radio Station licensing and MMSI numbers section in Part 4 also reference page 1-6 for the MCTS Centres’ MMSI numbers).

Canadian Coast Guard Marine Communications and Traffic Services (MCTS) Centres

To help ease the transition to GMDSS and bridge the communication gap between the two systems, Canadian Coast Guard MCTS Centres will continue to monitor the current distress and safety channels VHF Ch16 and MF 2182 kHz for the foreseeable future. Once Canada’s sea areas have all been implemented, lower cost DSC equipment is available, and it is determined that these services are no longer required, these listening watches may be discontinued. This decision will be evaluated at that time.

To supplement the broadcasting of Maritime Safety Information (MSI) on NAVTEX and INMARSAT EGC, MCTS Centres will continue safety broadcasts using the existing VHF continuous marine broadcast system.