There have been several incarnations of SOLAS, from the first version issued in 1914, two years after the Titanic disaster. It was followed by SOLAS 1920, 1930, 1939, 1948, 1960 and the most recent version, 1974, to which has already been tacked on over 40 additions.
SOLAS does not cover warships, small cargo ships, fishing vessels and sail boats or in regards to shipping on inland waters.
Each state that has signed onto SOLAS must certify that ships using its ports comply with SOLAS, including regular inspections.
Examples of the many mechanisms SOLAS utilizes to promote maritime safety is to address ship construction, specify load limits and standardize the handling of freight containers.
REFERENCES:
Duhaime, Lloyd, Maritime Law - A Glossary