TSSs, which appeared mainly during the 1970s and 1980s, regulate the circulation of vessels to reduce the risk of collision and running aground. Additionally, VTSs transmit information to vessels to help them navigate, and also monitor the TSSs and port approaches to detect any dangerous situations in order to coordinate any necessary safety and rescue operations. Lastly, MSRSs became mandatory at the end of the 1990s, with the aim of gathering more information on the dangers posed by maritime traffic. The data collected is now centralised in a Community maritime information exchange system (Directive 2002/59/EC).
The longest-standing air search and rescue tool is the offshore SARH, which airlifts crews from ships in distress. These helicopters are now assisted by salvage and emergency tow vessels, brought into service in France by the Marine Nationalin 1978, which tow vessels in difficulty (engine problems, leaks, etc.) to places of refuge currently designated by the maritime authorities (Directive 2002/59/EC). Lastly, pollution response vessels, which have multiplied in number since the 1990s and 2000s, are mainly used for cleaning up pollutants discharged into the sea before this pollution can reach the coast.
The gradual implementation of the maritime safety plan has led to a significant decrease in the loss of vessels. The plan therefore seems to be well adapted, even though the relative efficiency of each individual measure or tool may not be self-evident. If we look at previous studies, implementing TSSs and VTSs has greatly reduced the number of collisions and groundings (Cockcroft, 1983; Park and Redfenf, 1995), MSRSs have prevented major pollution incidents (Quivillic, 2004) and offshore SARHs make salvage missions more effective as they can reach crews on vessels in distress quickly (Quon and Laube, 1991). Lastly, accidents have also been reduced thanks to numerous technological advances (seafloor mapping, vessel positioning systems, etc.) and the measures taken since the end of the 1970s to combat the use of sub-standard vessels (Boisson, 1999).