Deepest saturation dive (Experimental)
Last updated: April 13, 2020 at 21:28 pm
701 msw (2,300 fsw) — COMEX Hydra 10, Hyperbaric Experimental Centre, Marseille, France, 1992. The dive protocol for the deepest experimental—dry—dive required a four-week pre-dive period, two days confinement at 10 m (33 ft), 13 days to compress to 675 m (2,215 ft) breathing hydro-heliox (a.k.a. hydreliox) (hydrogen 49%, helium 50% and oxygen 1%), and three days of bottom stage between 650 m (2,133 ft) and 675 m (2,215 ft). One of the divers, Théo Mavrostomos, then moved into a separate chamber and continued to 701 m (2,300 ft) for a period of seven hours. The record experiment required 24 days of decompression followed by 2.5 months post-dive monitoring. The experimental dive followed COMEX’s Hydra 8 record openwater saturation dive in 1988. (msw = metres sea water) (fsw = feet sea water)
Compagnie maritime d’expertises (COMEX): Hydra 10 : A 701 msw onshore record dive using “Hydreliox”
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Jeffrey Gallant is the Editor-in-Chief and Records Keeper of the Diving Almanac. He is also a contributing editor of DIVER Magazine, and the scientific director of the Greenland Shark and Elasmobranch Education and Research Group (GEERG). Jeffrey started diving in 1982.
