Iridium GMDSS offers coverage, capability, and cost advantages over the existing option, providing mariners
with enhanced safety at sea never before possible. Iridium GMDSS is the first and only GMDSS solution to offer truly global coverage, including above and below the 65th parallel, enhancing safety at sea and offering reliable coverage where Inmarsat does not.

All Iridium Connected® GMDSS terminals come standard with functionality for all satellite GMDSS services, and initiate both Distress Alert and Safety Voice quickly with the press of just one button. The Iridium Connected GMDSS terminal from Lars Thrane supplies all three satellite GMDSS services at a lower cost than the traditional alternative, allowing more vessels to access these life-saving services.


Iridium provides unprecedented coverage by enabling GMDSS satellite services around the entire globe, including
over the Arctic and Antarctic waters in Sea Area A4, even in adverse weather.

More than 1.4 million people, organizations, and things rely on Iridium to provide critical communications all over the world. Iridium’s crosslinked mesh architecture creates a web of coverage encompassing 100% of the planet from Low-Earth Orbit, providing low-latency, weather resilient services unlike any other satellite provider. As Iridium developed its GMDSS service, it underwent a multi-year process that included strict reviews and testing protocols, multiple panels of experts, and examinations to obtain Recognition from the International Maritime Organization (IMO) and a Letter of Compliance from IMO’s GMDSS regulator, the International Mobile Satellite Organization (IMSO). Furthermore, IMSO conducts quarterly examinations of Iridium’s operations to ensure that they continue to be in compliance with the IMO requirements.

As required by the IMO, commercial services are “pre-empted” by Priority GMDSS traffic, meaning your distress call will take priority over other voice and data services. This is done by design to ensure the safety of your crew and vessel.

The Iridium network is a trusted provider of safety and security services to more than 50,000 vessels around the world (80 percent of which are non-SOLAS). Many smaller, non-SOLAS vessels rely on GMDSS and other safety services to allow their crews to feel truly safe anywhere at sea.

Iridium GMDSS allows ships to quickly send definitive location and identification information to a Rescue Coordination Centers (RCC) and speak to an RCC operator to share key distress information, within 30 seconds of pressing the red distress button.

Additionally, Iridium GMDSS includes Iridium SafetyCastSM, which delivers important navigational and meteorological information to vessels with Iridium onboard, enabling proactive safety measures. Iridium’s global GMDSS services could have a significant effect on the success of a Search and Rescue operation.

Lars Thrane is manufacturing the first Iridium Connected GMDSS terminal, LT-3100S. Iridium Certus maritime equipment manufacturers are currently working with Iridium to develop auxiliary equipment for their existing broadband terminals to offer GMDSS through the Iridium Certus platform.

The default for GMDSS services is the international maritime language “Seaspeak”, which is based on English. However, Iridium GMDSS users can select a specific Rescue Coordination Center from their own region or country for all emergency communications, regardless of vessel location. This is recommended, if the on-board coordinators cannot speak English or Seaspeak.

Maritime Safety Information (MSI) is transmitted through an Enhanced Group Call (EGC) service called Iridium SafetyCast. The main type of information broadcast through this service is navigational and meteorological information and warnings. Depending on location, additional information, such as anti-piracy and ice reports, may be available. RCCs can also broadcast safety-related information through Iridium SafetyCast.