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Maritime Safety

MIL-SAT provides engineering support to ensure that all your Global Maritime Distress and Safety System (GMDSS) requirements are met.  If you are looking for a complete GMDSS system or replacement components for your existing GMDSS system, MIL-SAT has the solution for you.  Contact us today and we will be happy to assist you.

GMDSS has been developed by the maritime nations in the International Maritime Organization (IMO). The GMDSS is an automated ship-to-shore system using satellites and digital selective calling technology. GMDSS is mandated for ships internationally by the Safety of Life at Sea Convention (SOLAS), 1974, as amended in 1988, and carries the force of an international treaty.

The goal of GMDSS is to virtually guarantee that complying vessels will be able to communicate with an onshore station at any time, from any location, in case of distress or to exchange safety-related information.

As a basis, all GMDSS-regulated vessels are mandated to possess an Emergency Position-Indicating Radio Beacon (EPIRB), a Navigational Telex (NAVTEX) receiver, an Inmarsat-C SafetyNet receiver, a Digital Selective Calling (DSC) equipped VHF radiotelephone, two (2) each 9GHz Search and Rescue Transponder (SART), and two VHF handhelds for vessels between 300-500 gross tonnage. (Vessels over 500 gross tonnage will require three handheld VHFs to be carried.)

*Ships below 300 gross tonnage and those not engaged in international voyages are subject to the requirements of the administrations of their flag states.

Sea Areas:

GMDSS defines four sea areas based on the location and capability of onshore-based communication facilities. The definition of the Sea Areas for GMDSS is outlined below.

Sea Area - A1

An area within the radiotelephone coverage of at least one VHF coast station in which continuous digital selective calling (CH 70) alerting and radiotelephony services are available, as defined by the IMO. Within the range of shore-based VHF DSC coast station (40 nautical miles).

Sea Area - A2

An area, excluding Sea Area A1, within the radiotelephone coverage of at least one MF coast station in which continuous DSC (2187.5 kHz) alerting and radiotelephony services are available, as defined by the IMO. Within the range of shore-based MF DSC coast station (40 to 150 nautical miles)

Sea Area - A3

An area, excluding sea areas A1 and A2, within the coverage of an INMARSAT geostationary satellite in which continuous alerting is available. Within the coverage of an Inmarsat geostationary satellite (approximately 76°N to 76°S, excluding sea areas A1 and A2).

Sea Area - A4

This refers to the polar regions beyond areas A1, A2 and A3, beyond 76°N to 76°S.

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