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GMDSS stands for Global Maritime Distress and Safety System and is an international communications system for vessels operating at sea. GMDSS is part of the SOLAS Convention (Safety of Life at Sea) and is a mandatory requirement for all signatories of this international safety convention. The system was developed through the IMO (International Maritime Organisation) and global implementation became effective in 1999.

Victor Olerskiy, who served as the Deputy Minster of Transport of the Russian Federation for two years and has had a lifelong interest in the global shipping industry, presented at the Arctic Circle Assembly in 2015. The Arctic Circle is an open democratic platform facilitating international dialogue on the future of the Arctic region, including shipping in Arctic waters.

The Polar Code, which incorporates GDMSS as part of the SOLAS convention, establishes regulations for shipping safety in both polar regions of the world. More information about Arctic shipping routes can be found in the PDF attachment to this post.

Replacing Morse Code

Since the late nineteenth century after radio communication was invented, ships at sea would rely on Morse code to communicate with each other and with the shore, particularly for safety and distress telecommunications.

Following the sinking of the HMS Titanic in 1912, legislation began to be implemented across the world requiring ships at sea and radio stations on the coast to have and use equipment for radiotelegraphic communication via Morse code. Since inception, Morse code transmissions to and from ships have saved many thousands of lives. However, there is a limit to the amount of traffic that can be carried by Morse signals, and use of this requires a skilled and dedicated radio operator.

From 1979, the IMO began looking into new and better ways for ships to communicate distress signals using satellite technology. GMDSS equipment requirements for most ships began to be implemented in 1988 as part of the SOLAS convention and all ships subject to the convention were required to fit GMDSS by the 1st of February 1999.

A brief overview of Morse code can be found in the short video attachment to this post.

Setting the Standards for Communication Protocol

GMDSS has been setting the standard for communication protocol since full implementation twenty years ago. In times of distress, ships have a set standard for safety equipment, procedures and communications, sending a distress signal directly via a combination of radio or satellite communication equipment. All cargo ships and passenger ships over 300 gross tonnage are required to have GMDSS equipment if they sail on international waters. The system is also used as a way of transmitting general maritime safety information and for essential communications both ship-to-ship and ship-to-shore.

GMDSS Equipment

There are a variety of elements to GMDSS equipment, including enhanced marine radio. Traditionally equipped with VHF/MF/HF capacity, ships with GMDSS now also have what is known as DSC, or digital selective calling. This automates the process of keeping watch on distress and calling channels, reducing or eliminating the need for aural listeners.

DSC receivers respond to the unique identity numbers of vessels, called MMSI# or Maritime Mobile Service Identity numbers. GMDSS also uses satellite communications as well as traditional radiotelegraphic communications. Satellites further provide positioning detection technology known as EPIRB, or Emergency Position Indicating Radiobeacon.

SARTs, or Search and Rescue Transponders, are portable and can be used to determine to location or survivors of vessels that have sent a distress communication.

The implementation of GMDSS has saved many lives, but better safety procedures are always needed. In the infographic attachment you will find some recent statistics for incidents at sea that have resulted in the loss of ships.