A Simulated Dive at 2001 Feet

Abstract

ABSTRACT The "PHYSALIE VI" deep simulated dive was carried out as part of the C.N.E.X.O. - COMEX research program in COMEX HYPERBARJC RESEARCH CENTER from MAY 18 to JUNE 2, 1972. Two professional divers were progressively pressurized with an oxy-helium mixture to 2001 feet which they reached on MAY 24 at 1. 20 A.M. where they stayed for 80 minutes before decompression. The various physiological results obtained during this experimental dive permit to be optimistic with regard to the feasibility of industrial underwater work in the 1500 feet range. In view of the results obtained during the simulated deep dives "PHYSALIE V" (at 1706 feet) and "SAGITTAlRE II" (100 hours at 1640 feet), it was estimated that it should be possible to pressurize men to an equivalent depth of 2000 feet of sea water. This was investigated during the PHYSALIE VI deep diving experiment which took place in COMEX HYPERBARIC RESEARCH CENTER in MARSEILLES, from MAY 16 to JUNE 2, 1972. This experimental dive forms part of the Centre National pour Exploitation des Oceans (C. N. E. x. 0.)COMEX research programme and was carried out with the collaboration of several scientific teams from the University, the french Navy and Air Force, and the participation of the Centre National de la Recherche Scientifique (C. N. R. S.), and the Direction des Recherches et Moyens d'Essais (D. R. M. E.) for the neurophysiological aspects of the study. Two subjects were selected among the 5 COMEX divers who had already participated in experiment in the 1700 foot range and these were:–Patrice CHEMIN, aged 24, "world-recordman" at 1706feet.–Robert GAURET, aged 30, who had already participated in a 17 hours saturation dive at 1640 feet. On TUESDAY, MAY 16, at 4.00 P.M., Compression began according to a schedule resulting from the data collected during the "PHYSALIE V" and "SAGITTAIRE I" experiments. On MAY 18, at 2.54 A.M., a depth of 1148 feet was reached. They stayed 46 hours at this depthand on MAY 20 at 1.00 A.M., were further compressed down to 1755 feet which they reached on MAY 21 at 5.54 P.M. They spent the night at this depth and on MAY 22, between $.00 A.M. and 6.06 P.M., were compressed to 1854 feet where they stayed overnight. On MAY 23, at 8.00 A.M., the scientists responsible for the experiment decided it was possible to proceed deeper and compression was started again according to a specially designed schedule which brought the two divers to:2001 FEET, on MAY 24, at 1.20 A.M. They remained at this depth for 80 minutes, the necessary time for performing various physiological tests as well as a blood-sampling. The ambiant pressure was 61.61 ATA, and the breathing mixture contained:–0.6510 Oxygen; 0.1710 Nitrogen; 99.1510 Helium–0.0310 Water and a few ppm carbon dioxide.