Notice: The launch of the modernized Local Notices to Mariners (LNMs) and Light List (LL) application will be delayed beyond the scheduled 30 September 2024 launch date as a result of Hurricane Helene. We will post more information as soon as possible.
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COM Circulars

Document Name Description Format Size Date Posted
COM CIRC1.pdf Revision of the International Code of Signals and Proposed International RadioTelephone Code PDF 52 kb 15-Jun-62
COM CIRC2.pdf Co-Ordination of Safety at Sea and in the Air PDF 231 kb 21-Sep-62
COM CIRC3.pdf Co-Ordination of Safety at Sea and in the Air PDF 53 kb 4-Mar-63
COM CIRC4.pdf Revision of the International Code of Signals PDF 40 kb 8-Mar-63
COM CIRC5.pdf Emergency Position-Indicating Radio Beacons PDF 39 kb 13-May-63
COM CIRC6.pdf Interference Level on the RadioTelegraph Distress Frequency Direction-Finding by Ships on the 2 Mc/s Band PDF 209 kb 15-May-63
COM CIRC7.pdf RadioCommunication Requirements for the Ocean Data Service of the Intergovernmental Oceangraphic commission PDF 303 kb 30-Jan-64
COM CIRC8.pdf RadioCommunication Requirements for the Ocean Data Service of the International Oceangraphic commission PDF 66 kb 30-Apr-64
COM CIRC9.pdf Listening for Distress Calls PDF 1902 kb 30-Apr-64
COM CIRC9-Corr1.pdf Listening for Distress Calls PDF 15 kb 11-Dec-64
COM CIRC102.pdf INMARSAT EGC Safetynet System Draft International Safety Manual PDF 1036 kb 31-May-90
COM CIRC102-Rev1.pdf INMARSAT EGC Safetynet System Draft International Safety Manual PDF 135 kb 4-May-92
COM CIRC102-Rev2.pdf INMARSAT EGC Safetynet System Draft International Safety Manual PDF 1517 kb 7-Jul-93
COM CIRC102-Rev3.pdf INMARSAT EGC Safetynet System Draft International Safety Manual PDF 1171 kb 3-Jul-91
COM CIRC103.pdf Design and Installlation Guidelines for INMARSAT standard-C ship earth stations and Enhanced Group Call (EGC) receivers PDF 546 kb 31-May-90
COM CIRC104.pdf Coding of 406 MHz Satellite EPIRBs PDF 58 kb 26-Jun-91
COM CIRC105.pdf Clarification of Certain Provisions of the 1988 SOLAS Amendments for the GMDSS PDF 91 kb 6-Aug-91
COM CIRC106.pdf Testing of MF Digital Selective Calling Equipment Installed for Distress and Safety by ships and coast stations PDF 23 kb 6-Aug-91
COM CIRC107.pdf Shortage of Supply of 406 MHz EPIRBs PDF 17 kb 5-Aug-91
COM CIRC108.pdf GMDSS Operating Guidance for Masters of Ships in Distress Situations PDF 32 kb 23-Jan-92
COM CIRC109.pdf Use if Frequency 8364 KHz for Survival Craft PDF 15 kb 23-Apr-92
COM CIRC110.pdf Clarification of SOLAS Regulations IV/ 6.1, IV/ 6.2.2 and IV/ 10.1.1.3 PDF 24 kb 8-Feb-93
COM CIRC110-Corr1.pdf Clarification of SOLAS Regulations IV/ 6.1, IV/ 6.2.2 and IV/ 10.1.1.3 PDF 9 kb 16-Mar-93
COM CIRC111.pdf Standard Report Formats for Piratical Incidents PDF 37 kb 10-Feb-93
COM CIRC112.pdf Implementation of Maritime Safety Information (MSI) Broadcasts VIA SAFETYNET in areas not covered by NAVTEX PDF 19 kb 10-Feb-93
COM CIRC113.pdf Provisions of Maritime Safety Information (MSI) Broadcasts in the International SAFETYNET Service PDF 143 kb 10-Feb-93
COM CIRC114.pdf IMO/IHO Guide to Drafting Radio Navigational Warnings for the World-Wide Navigational Warning service PDF 265 kb 10-Feb-93
COM CIRC114Rev1.pdf IMO/IHO Guide to Drafting Radio Navigational Warnings for the World-Wide Navigational Warning service PDF 262 kb 27-May-94
COM CIRC115.pdf Discontinuation of Morse Code Services in the MF Radiotelegraphy band PDF 28 kb 10-Feb-93
COM CIRC116.pdf Provision of GMDSS Radio Installations with Positions Updating Facility PDF 26 kb 11-Jan-94
COM CIRC117.pdf Clarification of the application if certain provisions of chapter IV of the SOLAS convention PDF 18 kb 10-Jan-94
COM CIRC122.pdf Selection of More than one fixed area in the INMARSAT-C Systems PDF 23 kb 14-Feb-95
COM CIRC123.pdf List of NAVAREA Coordinators PDF 59 kb 14-Feb-95
COM CIRC124.pdf IMO/IHO Guide to Drafting Radio Navigational Warnings for the World-Wide Navigational Warning service PDF 282 kb 20-Feb-95
COM CIRC125.pdf Recommendations on the use of batteries for two-way VHF Radiotelephone apparatus PDF 44 kb 20-Feb-95
COM CIRC127.pdf Guidelines for Avoiding False Distress Alerts PDF 176 kb 23-Feb-95
COM CIRC128.pdf Guidelines for use in Evaluating regional Mobile Satellite Systems PDF 89 kb 22-May-95
COM CIRC129.pdf Amendments to the International Code of Signals PDF 49 kb 21-Jul-95

NOTE: The most recent Circulars may also be found at the IMO's website.