COMEX (or Compagnie Maritime d'Expertises) is a French company specializing in engineering and deep diving operations, created in November 1961 by Henri-Germain Delauze and ran by him until his death in 2012. This company is known worldwide for its technology in regard to underwater exploration at great depths. Its line of business includes: * hyperbaric testing facilities, * oceanographic research ships (Minibex and Janus), * testing pool. COMEX carried out pioneering work in very deep

saturation diving Saturation diving is diving for periods long enough to bring all tissues into equilibrium with the partial pressures of the inert components of the breathing gas used. It is a diving mode that reduces the number of decompressions divers working ...

. The company experimented with the use of

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...

in the divers'

breathing gas A breathing gas is a mixture of gaseous chemical elements and compounds used for respiration. Air is the most common and only natural breathing gas, but other mixtures of gases, or pure oxygen, are also used in breathing equipment and enclosed ...

. This work with

heliox Heliox is a breathing gas mixture of helium (He) and oxygen (O2). It is used as a medical treatment for patients with difficulty breathing because mixture generates less resistance than atmospheric air when passing through the airways of the lung ...

(a breathing gas mixture of

helium Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. ...

and

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

) and

hydreliox Hydreliox is an exotic breathing gas mixture of helium, oxygen and hydrogen. For the Hydra VIII (Hydra 8) mission at 50 atmospheres of ambient pressure, the mixture used was 49% hydrogen, 50.2% helium, and 0.8% oxygen. It is used primarily for r ...

(an exotic breathing gas mixture of

and

gas) mixtures started with Hydra I in 1968. The saturation diving physiology studies were conducted with helium from and with hydrogen from . The diving depth record for off-shore (saturation) diving was achieved in 1988 by a team of COMEX

professional diver Professional diving is underwater diving where the divers are paid for their work. The procedures are often regulated by legislation and codes of practice as it is an inherently hazardous occupation and the diver works as a member of a team. Du ...

s performing pipe line connection exercises at a depth of of seawater ( msw/fsw) in the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ...

, whist breathing a

mixture, as part of the Hydra VIII (Hydra 8) programme. The Hydra programme culminated with Hydra X (Hydra 10) in 1992 when COMEX diver Théo Mavrostomos achieved a record simulated dive of in an onshore hyperbaric chamber. The use of hydrogen for diving was in part driven by the need to overcome the problems of

high-pressure nervous syndrome High-pressure nervous syndrome (HPNS – also known as high-pressure neurological syndrome) is a neurological and physiological diving disorder which can result when a diver descends below about using a breathing gas containing helium. The eff ...

(HPNS). However, there was another reason for the interest in using hydrogen in a

. In 1987, Comex was part of a Canadian-French consortium that was building the world’s first commercial nuclear mini-submarine. This submarine, Saga, was a prototype intended to be used for oil exploration and development under the Arctic ice. Saga was built on a hull originally constructed by

Jacques-Yves Cousteau Jacques-Yves Cousteau, (, also , ; 11 June 191025 June 1997) was a French naval officer, oceanographer, filmmaker and author. He co-invented the first successful Aqua-Lung, open-circuit SCUBA ( self-contained underwater breathing apparatus). T ...

but not completed due to lack of funds. Saga would have a complete saturation diving system on board. The nuclear power plant would be able to produce large volumes of hydrogen and oxygen through the

electrolysis of water Electrolysis of water, also known as electrochemical water splitting, is the process of using electricity to decompose water into oxygen and hydrogen gas by electrolysis. Hydrogen gas released in this way can be used as hydrogen fuel, or remi ...

. This would provide plentiful amounts of

for autonomous diving operations under the Arctic ice cap. The project suffered tax problems in Canada which caused political repercussions between the French and Canadian governments. Saga did undergo successful sea trials in 1991 but without the intended nuclear power plant. Underwater propulsion was provided by a

Stirling engine A Stirling engine is a heat engine that is operated by the cyclic compression and expansion of air or other gas (the ''working fluid'') between different temperatures, resulting in a net conversion of heat energy to mechanical work. More specif ...

and surface propulsion by a diesel engine. The project was abandoned and Saga was laid up at Marseille.

References

External links

Official COMEX Website

Historique Henri-Germain Delauze
{{Authority control Diving engineering Manufacturing companies based in Marseille Commercial diving contractors