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International Maritime Org
Primary Mission Areas:
Maritime Information:
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.