DIVING TECHNOLOGY - MEANS, METHODS, RESEA RCH AND FUTURE

In France, diving activities are practised by a large number of people , included recreational or sport divers, commercial and military diver s. Different diving technics are used, depending on depth and duration of underwater interventions : human intervention under pressure (divi ng), one atmosphere submarine, remotely operated vehicle (ROV). The di ver used specific equipments and procedures with air, heliox (oxygen - helium), hydrox (oxygen-hydrogen) or hydreliox (oxygen-hydrogen-heliu m) breathing gas mixtures; and for decompression, specific tables adap ted to gas mixtures and underwater time exposures. In 1988, six Comex and French Navy divers worked at a record depth of 534 msw with hydrel iox and in 1992 a world record onshore dive at 701 msw was performed b y Comex in Marseille. These dives showed the efficiency of hydrogen di ving at very deep depth. Among a lot of submarines built for undersea works, the latest in the range of Comex's innovative submarines, the ' 'Remora 2000'' combines the functions and instrumentation of an oceano graphic subsea vessel with eye catching design of a recreational subma rine. Now, ROV's replace more and more the diver on oil subsea offshor e fields.