What is the primary inert gas that divers are concerned with?

The primary inert gas that divers are concerned with is nitrogen. When divers descend underwater, they are exposed to increased pressures, which cause nitrogen, present in the breathing gas (like air), to dissolve into the body’s tissues and blood. This increase in nitrogen solubility is a critical aspect of dive physiology, as it can lead to potential complications such as decompression sickness (DCS) if the diver ascends too quickly after a dive.

Decompression sickness occurs when nitrogen that has been absorbed into the body comes out of solution too rapidly during ascent, leading to the formation of bubbles in tissues and blood. Therefore, managing nitrogen exposure through safe diving practices, such as adhering to ascent rates and no-decompression limits, is essential for preventing DCS.

While other gases like oxygen, helium, and hydrogen may have specific roles in diving and can present their own risks (e.g., oxygen toxicity at high pressures or narcosis from helium), nitrogen remains the primary inert gas of concern due to its widespread presence in the majority of breathing mixtures used in recreational diving and its significant physiological effects.