UNDERWATER DIVING METHOD AND SYSTEM COMPRISING BREATHING GAS CONTAINING HYDROGEN

摘要

The technical field of the invention relates to medium depth and deep sea underwater diving for industrial applications. The invention concerns a method and a system for the pressurization and decompression of a diver (8) and for providing him with breathing gas containing hydrogen. According to the present invention, the person is pressurized to an absolute pressure P1 (14) of at least 0.45 Mpa with a first type of breathing gas which does not contain hydrogen; the person (8) is supplied, based on at least this pressure P1 (14) with a second type of breathing gas at pressure P according to the diving depth p. The second breathing gas is of the hydreliox type and contains hydrogen at a minimum partial pressure of 0.33 Mpa, less than 4 volume percent oxygen, helium at a pressure over 0.1 Mpa and other gases such as nitrogen at a pressure below 0.09 Mpa; the hydreliox mixture supply so obtained at pressure P2 (18) at the desired diving depth p2 is maintained.