Hydrox (breathing gas)

Hydrox is a breathing gas mixture of hydrogen and oxygen, which is used in scuba diving in very great depth. It allows a descent to a depth of up to 700 meters.

History

Only many years later, the studies were taken with hydrogen again, first by the U.S. Navy, then by the French company Comex developed the method for achieving a depth between 500 and 700 m, with the help of hydrogen-based gas mixtures such as Hydrox (hydrogen and oxygen) or hydreliox (hydrogen, helium, and oxygen).

Properties and Uses

With various mixtures Hydrox diving depths could be up to 700 meters reached. Hydrox helps especially against the High Pressure Nervous Syndrome, the most common deep-sea diver 's disease, which is caused by the helium mixtures such as heliox, and trimix hydreliox. As Hydrox does not contain nitrogen, there are no nitrogen narcosis. However, hydrogen has a narcotic effect. This effect is used in hydreliox order to mitigate helium as an antagonist of the HPNS. Disadvantages are the high explosivity of a hydrogen-oxygen mixture as an explosive gas as well, because of the very high thermal conductivity of hydrogen ( 0.1805 W / ( m · K) ), a strong cooling of the lungs. Furthermore Hydrox can only be used at depths below 30 meters, so two different breathing gases must be carried.