The International Convention for the Safety of Life at Sea (SOLAS) is the most important treaty protecting the safety of merchant ships. The first version of the treaty was passed in 1914 in response to the sinking of the RMS Titanic. It prescribed numbers of lifeboats and other emergency equipment along with safety procedures, including continuous radio watches.
Newer versions were adopted in 1929, 1948, 1960 and 1974. The 1960 Convention - which was activated in 1965 - was the first major achievement for International Maritime Organization (IMO) after its creation and represented a massive advance in updating commercial shipping regulations and in staying up to date with new technology and procedures in the industry. The 1974 version simplified the process for amending the treaty and a number of amendments have been adopted. In particular, amendments in 1992 replaced Morse code with the Global Maritime Distress and Safety System (GMDSS), beginning in 1999.
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