IMO Documents Categories IMO Conventions SAR Administration SAR Operations Medical Communications - Systems Communications - Procedures Maritime Safety Information Other Information Model Courses Various Shop Communications - Systems Guidance Available for Purchase Please visit the IMO Bookshop. IMO Resolutions MSC.131(75) - Maintenance of a Continuous Listening Watch on VHF Channel by SOLAS Ships Whilst at Sea and Installation of VHF DSC Facilities on Non-SOLAS Ships MSC.199(80) - Adoption of Amendments to Provision of Radio Services for the Global Maritime Distress and Safety System (GMDSS)Amends Resolution A.801(19). MSC.1/Circ 1518: Amendments to the International Convention for the Safety of Life at Sea, 1974, as amended A.887(21) - Establishment, Updating and Retrieval of the Information Contained in the Registration Databases for the Global Maritime Distress and Safety System (GMDSS) A954(23) - Proper Use of VHF Channels at Sea A.1001(25) - Criteria for the Provision of Mobile Satellite Communication Systems in the Global Maritime Distress and Safety System (GMDSS) IMO Circulars COMSAR/Circ.37/Rev.1 - Guidance on Minimum Communication Needs of Maritime Rescue Co-ordination Centres (MRCCs) GMDSS.1/Circ.22: GMDSS Master Plan of shore-based facilities – 30 Jul 2018Note that this Circular is updated fairly frequently. It is being replaced by a new GISIS ‘GMDSS’ module. COMSAR.1/Circ.53/Rev.2 - List of Land Earth Station (LES) Operation Coordinators in the Inmarsat SystemNote that this Circular is updated fairly frequently MSC.1/Circ.1208 - Promoting and Verifying Continued Familiarization of GMDSS Operators on Board Ships MSC.1/Circ.1210 - COSPAS-SARSAT international 406 MHz Beacon Registration Database - Revision 1 MSC.1/Circ.1382/Rev.2 - Revised Questionnaire on Shore-Based Facilities for the Global Maritime Distress and Safety System (GMDSS) Manage Cookie Preferences