Deepest saturation dive (Openwater)
Last updated: March 26, 2020 at 2:17 am
534 m (1,752 ft) — COMEX Hydra 8, Hyperbaric Experimental Centre, Marseille, France, 1988. Breathing a gas mixture of hydro-heliox (hydrogen 49%, helium 50% and oxygen 1%), it took four COMEX (Compagnie maritime d’expertises) divers, and two divers of the Marine nationale (French Navy), eight days to compress inside a chamber to the maximum bottom pressure of 53 atmospheres (780 psi) at the Hyperbaric Experimental Centre. The pressurised chamber was then lowered to the same depth off Marseille, where the divers exited to conduct six open water dives for a total of 28 hours of work at depths of 1,706 ft (520 m) and 1,752 ft (534 m). After completing their assigned tasks, including pipeline connection exercises, the divers re-entered the chamber for 18 days of decompression, thus completing the experiment known as Hydra 8. The record open water dive in the Mediterranean led to COMEX’s record experimental saturation dive in 1992.
COMEX divers: Thierry Arnold, Régis Peilho, Patrick Raude, Louis Schneider.
Marine nationale divers: Serge Icart, Jean-Guy Marcel-Auda.
Compagnie maritime d’expertises (COMEX)
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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.
