When divers descend beyond 55 meters, standard air becomes a liability. Nitrogen narcosis impairs judgment, and oxygen toxicity becomes a real threat under increased partial pressures. The solution is Heliox – a precisely engineered breathing mixture of helium and oxygen that keeps divers alive and lucid at extreme depths. Here is why it works: • Helium has a significantly lower molecular weight than nitrogen (4 g/mol vs 28 g/mol), which means it does not produce the same narcotic effect on the central nervous system under pressure • Because helium is far less soluble in body tissues compared to nitrogen, it reduces the risk of decompression sickness during ascent, though careful staged decompression is still critical • Helium also has a lower density, which decreases the work of breathing at depth where gas density increases proportionally with ambient pressure • The oxygen fraction in Heliox is carefully calculated based on the target depth to keep the partial pressure of O2 wi...