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Why seafarers rely on Inmarsat

Safety is in our DNA – we were set up in 1979 by the International Maritime Organization (IMO) to provide reliable satellite safety communications.

When disaster strikes – a catastrophic storm, a collision, a medical emergency – seafarers know that they can rely on our marine safety management services to get help fast.

We’ve continued to ensure our maritime safety services go above and beyond the IMO’s Safety of Life at Sea (SOLAS) and Global Maritime Distress and Safety System (GMDSS) requirements – by, for example, exceeding the demand for satellite and ground network availability of 99.9 percent.

Today, over our L-band network, we support both SOLAS and non-SOLAS vessels and some 1.6 million seafarers depend on us for a communications lifeline that is reliable and unaffected by bad weather.

What is the GMDSS?

The Global Maritime Distress and Safety System or GMDSS is an international maritime safety system, which uses satellite and terrestrial technology and ship-board radio systems to prevent accidents from happening and to automatically alert the rescue authorities and nearby vessels quickly in an emergency.

Under the Safety of Life at Sea (SOLAS) convention, cargo ships of 300GRT and upwards and all passenger ships on international voyages must be equipped with satellite and radio equipment that conforms to international standards.

Inmarsat is the leading provider of GMDSS-approved satellite communication services. Our Inmarsat C service has been keeping seafarers safe at sea every day since the inception of GMDSS in 1999 through the receipt and transmission of vital ship-to-shore and shore-to-ship distress alerts.

In May 2018, Fleet Safety, our next-generation satellite safety service delivered over FleetBroadband and Fleet One, received formal GMDSS recognition by the IMO, marking the most significant advance in maritime safety for a generation.

Our SafetyNET, SafetyNET II and RescueNET services play a crucial role in enhancing the safety of life at sea by broadcasting Maritime Safety Information and Search & Rescue – related information messages to Inmarsat C, Mini C and Fleet Safety terminals.

Our GMDSS services are closely monitored and overseen by the International Mobile Satellite Organization (IMSO) to ensure compliance with the requirements set by IMO. We maintain a collaborative relationship with IMSO, conducting regular exercises to vigorously test the reliability and effectiveness of our GMDSS system.   This ensures that our services are fail-safe and accessible to seafarers across the globe 24/7.

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Maritime safety and security requirements

Inmarsat’s dedicated Maritime Safety Services team work closely with all organisations involved in the safety and security of ships and seafarers.

They advise on methods of using Inmarsat services and networks to comply with the following safety and security requirements for ships at sea.

Ship Security Alert Systems (SSAS)

The SSAS is used by ships to transmit a security alert to a competent authority when the security of the ship is under threat or has been compromised.

IMO legislation states that the ship’s security alert system shall:

  • Be initiated by pressing a dedicated SSAS button and transmitting a ship-to-shore security alert to a competent authority designated by the administration, which may include the company, identifying the ship, its location and indicating that the security of the ships is under threat or has been compromised
  • Not send the ship security alert to any other ships
  • Not raise any alarm on board the ship
  • Continue the ship security alert until deactivated and/or reset.

Ship security alerts can be sent using Inmarsat C and Mini C, and relevant hardware and software can be added to the existing GMDSS terminals to support the service. Dedicated SSAS models are also available from MES manufacturers.

Long Range Identification and Tracking (LRIT) of ships

LRIT is not part of the GMDSS communication requirements either but its equipment – particularly Inmarsat C and Mini C terminals – can also be used to support the system.

LRIT is a SOLAS regulation included in Chapter V, which applies to ships constructed after 31 December 2008 with a phased-in implementation time for existing ships.

Regulations require that by default LRIT reports should be transmitted every six hours to the LRIT Data Centre with frequency of transmission to be controlled remotely, allowing for reports to increase as security levels change up to a rate of one report every 15 minutes. The LRIT information that ships are required to transmit includes its position and the date and time to contracting governments and administrations.

Maritime Rescue Co-ordination Centres

Distress alerts, calls and distress priority messages transmitted over the Inmarsat network are routed via its Land Earth Stations (LESs) or Shore Access Stations (SASs) to shore-based Maritime Rescue Co-ordination Centres (MRCCs) around the world.

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