The primary purpose of a decompression gas is to achieve what?

The primary purpose of a decompression gas is to lower the partial pressure of inert gas in alveolar air. During a dive, divers absorb various inert gases, like nitrogen, under pressure. When ascending, the pressure decreases, and if not managed properly, these gases can form bubbles in the body, leading to decompression sickness, also known as "the bends."

Using a decompression gas, which typically contains a mix of gases with lower amounts of nitrogen and higher amounts of oxygen or helium, helps in effectively reducing the partial pressure of inert gas in the lungs. This reduction facilitates the safe elimination of these gases from the body as the diver ascends, minimizing the risk of bubble formation and allowing for a safer return to the surface. Therefore, the use of a decompression gas is critical in managing inert gas levels and ensuring diver safety during decompression phases.