Why is proper gas selection crucial for decompression dives?

Proper gas selection is crucial for decompression dives because it directly impacts the amount of nitrogen absorbed by the body during the dive. When divers descend, they inhale a mixture of gases that includes nitrogen, which, under pressure, dissolves into the body tissues. For deeper and longer dives, the accumulated nitrogen can become a risk factor for decompression sickness, often referred to as "the bends," when divers ascend too quickly.

By selecting the appropriate gas mix, such as a blend with a lower percentage of nitrogen (like Nitrox), divers can minimize nitrogen absorption and thereby reduce the risks associated with decompression. This careful choice puts the diver in a better position to safely ascend, allowing their body to off-gas the absorbed nitrogen safely during controlled decompression stops.

While buoyancy control, ear equalization, and visibility are important considerations for diving, they are not directly influenced by gas selection in the same manner that nitrogen absorption is.