Foundations
Beyond Compressed Air: From Nitrox to Hydrogen, or Why Divers Use Different Breathing Gases
Ordinary compressed air is ideal for many dives, but for certain dives other breathing gases are used, such as Nitrox (air enriched with extra oxygen) and Trimix (a mixture of nitrogen, oxygen, and helium). In this article, we trace the development of diving through these breathing gases: from the rise of Nitrox to experiments with hydrogen-containing mixtures for extremely deep dives. We discuss applications of different gases, methods for mixing, analyzing, and identifying gases, and the related training. This is not a practical manual, but an accessible guide to the gas physics and chemistry behind every dive.
