GMDSS Handbook Part-1

GMDSS Handbook

Part - 1 Introduction

1.1 History
Since its establishment in 1959, the International Maritime Organisation (IMO), in its efforts to enhance safety at sea by the adoption of the highest practicable standards, has sought to improve the radiocommunication provisions of the International Convention for the Safety of Life at Sea (SOLAS) and to exploit the advances made in radio communication technology.
The shipborne radiocommunication equipment prescribed by the 1960 and 1974 SOLAS Conventions consisted of radiotelegraph equipment for passenger ships of all sizes and cargo ships of 1,600 tons gross tonnage and upwards, as well as radiotelephone equipment for cargo ships of 300 to 1,600 tons gross tonnage. The ships so fitted, although they could receive a distress alert, could not communicate with each other, and it was not until 1984 that all ships were required to be able to communicate by means of VHF and MF radiotelephone. The range of transmission on MF was only 150 miles, so for ships beyond this distance from the nearest coast station, the old system is essentially a ship-to-ship distress system.
In 1972, with the assistance of the International Radio Consultative Committee (CCIR), IMO commenced a study of maritime satellite communications which resulted in the establishment, in 1979, of the INMARSAT organisation, thus making available to shipping an international satellite communications system. In 1973, through Assembly resolution A.283(VIII), IMO reviewed its policy on the development of the maritime distress system so as to incorporate satellite communications and foresaw the possibility of automatic alerting and transmission of maritime distress and safety information.
In 1979 the International Conference on Maritime Search and Rescue adopted the International Convention on Maritime Search and Rescue, 1979 (1979 SAR Convention), the ultimate objective of which is to establish a global plan for maritime search and rescue {SAR) on a framework of multilateral or bilateral agreements between neighbouring states on the provision of SAR services in coastal and adjacent ocean waters to achieve co-operation and mutual support in responding to distress incidents. The Conference also invited IMO to develop a global maritime distress and safety system, including telecommunication provisions, for the effective operation of the search and rescue plan prescribed in the 1979 SAR Convention.
The IMO Assembly, at its eleventh session in 1979, considered the existing arrangements for maritime distress and safety communications and decided that a new global maritime distress and safety system should be established to improve distress and safety radiocommunications and procedures. In conjunction with a co- ordinated search and rescue infrastructure, it would iI)corporate recent technical developments and significantly improve the safe,ty of life at sea.
With the assistance of the International Telecommunication Union (ITU), CCIR, other international organisations, notably the World Meteorological Organisation (WMO), the International Hydrographic Organisation (IHO), INMARSAT , and the COSPAS-SARSAT partners, IMO developed and proved the various equipment and techniques used in the global maritime distress and safety system (GMDSS). The ITU also established the appropriate regulatory framework for the implementation of the GMDSS.
The 1983 and 1987 World Administrative Radio Conferences for the Mobile Services (W ARC-Mob-83 and 87) and W ARC-92 adopted amendments to the ITU Radio Regulations which prescribe the frequencies, operational procedures and radio personnel for the GMDSS.
In 1988, the Conference of Contracting Governments to the 1974 SOLAS Convention on the Global Maritime Distress and Safety System (GMDSS Conference) adopted amendments to the 1974 SOLAS Convention concerning radiocommunications for the GMDSS, together with several relevant resolutions. These amendments entered into force on 1 February 1992, and the GMDSS will be fully implemented on 1 February 1999.
1.2 The old system and the need for improvement
The old maritime distress and safety system, as defined in chapter IV of the 1974 SOLAS Convention in force prior to 1 February 1992, was based on the requirements that certain classes of ships, when at sea, keep continuous radio watch on the international distress frequencies assigned in accordance with the ITU Radio Regulations and carry radio equipment capable of transmitting over a minimum specified range. The master of any ship at sea should, on receiving a signal that a ship, aircraft or survival craft is in distress, proceed with all speed to the assistance of the persons in distress, informing them that he is doing so. Since the minimum specified range of communications provided by the required shipborne equipment is 100-150 nautical miles, assistance to a ship in distress could generally only be rendered by other shipping in the vicinity of an incident, which means that the old system is primarily intended for ship-to-ship operation. However , in accordance with the ITU Radio Regulations, coast stations generally maintain a continuous watch during their service hours on the distress frequencies.
The old system includes two major manually operated subsystems:
- The Morse telegraphy system on 500 kHz for all cargo ships of 1,600 tons gross tonnage and over and all passenger ships. Since Morse competence is essential to the operation of this system, a Morse- qualified radio officer is required on all ships having radiotelegraph installation.
- The radiotelephony system on 2182 kHz and 156.8 MHz for all cargo ships of 300 tons gross tonnage and over and all passenger ships, which provides common distress communications for all ships, subject to the 1974 SOLAS Convention.
It has proved difficult to make any significant progress in the communication arrangements for a ship in distress when it is beyond the range of MF coast radio stations, although various measures have been implemented to improve the situation.
The introduction of modern technology, including satellite and digital selective calling techniques, enables a distress alert to be transmitted and received automatically over long range with a significantly higher reliability.