Psychophysiological reactions in humans during an open sea dive to 500 m with a hydrogen-helium-oxygen mixture.
J H Abraini, M C Gardette-Chauffour, E Martinez, J C Rostain, C Lemaire · Journal of applied physiology (Bethesda, Md. : 1985) · 1994
Research-use notice
Independent study record
Each H2HUBB study page organizes source-linked research details for educational use. Interpretation should remain proportional to the study design, population, controls, and limitations.
H2HUBB TAKEAWAY
Six commercial divers were evaluated during an open-sea dive to 500 meters while breathing a mixture containing 49% hydrogen together with helium and oxygen. The study reported moderate high-pressure nervous-system symptoms and detectable narcotic effects of hydrogen while the divers completed the operational dive. It is included as related safety and physiology background because this extreme hyperbaric exposure was not a therapeutic hydrogen treatment and cannot be generalized to clinical use.
What the Publication Reported
The authors reported moderate high-pressure nervous-system symptoms, detectable narcotic effects of hydrogen, and successful completion of the operational diving task.
How Molecular Hydrogen Was Addressed
The breathing mixture contained 49% hydrogen together with helium and oxygen under extreme hyperbaric conditions.
How the Publication Was Conducted
Six commercial divers underwent neurological and psychosensorimotor testing during an operational open-sea dive to 500 meters.
What the Researchers Studied
Nevertheless, the divers successfully carried out the main purpose of the operational dive, which was to prove the feasability of such diving methods by connecting specific elements of an offshore oil.
How Molecular Hydrogen Was Used
Six commercial divers were investigated for neurological and psychosensorimotor responses during an open sea dive to 500 m with a hydrogen-helium-oxygen mixture containing 49% hydrogen. showed only moderate neurological symptoms of high-pressure nervous syndrome, whereas the narcotic effect of hydrogen was detectable, as investigated by psychosensorimotor tests. Finally, these data support the hypothesis that hydrogen can alleviate some of the symptoms of the high-pressure nervous syndrome and can constitute a useful gas for commercial diving, as it decreases the density of the breathing mixture and therefore improves the living conditions, work, and comfort of the divers.
What the Researchers Found
Finally, these data support the hypothesis that hydrogen can alleviate some of the symptoms of the high-pressure nervous syndrome and can constitute a useful gas for commercial diving, as it decreases the density of the breathing mixture and therefore improves the living conditions, work, and comfort of the divers.
H₂ Mechanisms / Biological Findings
The source material reviewed did not establish a specific molecular hydrogen mechanism for the reported findings.
Authors’ Conclusion
A distinct authors’ conclusion was not available in the source material reviewed by H2HUBB.
H2HUBB Evidence Boundary
This human diving-physiology study used a hydrogen–helium–oxygen breathing mixture under extreme hyperbaric conditions. It is included as safety and physiology background, not as therapeutic hydrogen treatment.