Hydra 8: Pre-commercial Hydrogen Diving Project

Conference paper
Part of the Advances in Underwater Technology, Ocean Science and Offshore Engineering book series (AUTOO, volume 14)


Deep divers are exposed to three types of environmental stresses:
  • the high-pressure nervous syndrome (HPNS), which is related to the effects of the hydrostatic pressure on the central nervous system. These appear at around 200 m and increase with depth, causing motor disturbances that may impair divers’ efficiency.

  • stress caused by the density of the breathing mixture, which increases with depth. Breathing dense gas requires increased ventilatory efforts that may reduce divers’ work capacity.

  • the fatigue of long saturation periods (confinement, thermal stress, bad sleep, lack of appetite, etc.) that is generally related to body-weight losses.


Fire Risk Chamber System Saturation System Lower Explosion Limit Simulated Dive 
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Copyright information

© Society for Underwater Technology (Graham & Trotman) 1988

Authors and Affiliations

  1. 1.Comex ServicesFrance

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