The International Maritime Organization (IMO) is a London-based United Nations organization whose decisions have treaty status in the U.S. and most of the world. The predominant IMO treaty document affecting maritime communications and other marine electronics is the Safety of Life at Sea (SOLAS) Convention. Chapter IV of that Convention, the chapter defining telecommunications requirements on passenger ships and ships greater than 300 tons on international voyages, was amended in 1988, replacing what primarily had been a Morse telegraphy based system with newer, more modern means of communications. That system, comprising satellite and terrestrial radiocommunications, is collectively know as the Global Maritime Distress & Safety System, or GMDSS. Since SOLAS Chapter IV defines an international maritime safety telecommunications system having treaty status, that chapter has become the architect for maritime telecommunications used by vessels not regulated by SOLAS, such as recreational boaters and commercial fishing vessels. Although GMDSS was designed primarily for ships subject to the SOLAS Convention, it will also affect safety telecommunications of all vessels.

SOLAS Chapter V (pdf) describes navigation safety requirements for governments as well as all ships (except warships) on all voyages. Changes to SOLAS Chapter V, including requirements for carriage of global navigation satellite systems such as GPS, electronic chart requirements, ship transponders, and maritime safety broadcast requirements, etc., are being considered now.

The U.S. Coast Guard represents the U.S. at meetings of the IMO. The IMO committee responsible for maritime safety is, not surprisingly, the Maritime Safety Committee (MSC). The two subcommittees under the MSC having responsibility for maritime communications and radionavigation, the Radiocommunications and Search and Rescue (COMSAR) Subcommittee and the Safety of Navigation (NAV) Subcommittee, meet about once per year. The Coast Guard holds public advisory meetings, called Shipping Coordination Committee and Safety of Life at Sea (SOLAS) working group meetings, in Washington DC in preparation for the IMO meetings in London. The SOLAS WG meeting for Radiocommunications and Search and Rescue generally meets monthly, on the third Thursday of the month. The MSC Shipping Coordination Committee meeting and the SOLAS WG for Navigation generally meets less frequently. These meetings are open to the public. You may contact the IMO directly for copies of conventions, codes, Assembly Resolutions and other information.