What is the method used to reduce the risk of decompression sickness when using EANx?

The method used to reduce the risk of decompression sickness when using Enriched Air Nitrox (EANx) is to decrease nitrogen exposure. EANx contains a higher percentage of oxygen and a proportionally lower percentage of nitrogen compared to regular air. This reduced nitrogen exposure is beneficial as nitrogen is the gas that contributes most significantly to the risk of decompression sickness. When divers breathe air that is richer in oxygen, they absorb less nitrogen into their bodies during the dive. Consequently, this helps minimize the likelihood of nitrogen bubbles forming in the bloodstream during ascent, which is the primary cause of decompression sickness.

The other options, while relevant to diving in various contexts, do not directly contribute to reducing decompression sickness associated with nitrogen. Increased water temperature, for instance, can actually increase the body's absorption of nitrogen rather than decrease it. Changing dive sites does not inherently reduce nitrogen exposure; it merely alters the environment and conditions of the dive. Utilizing heavier weights may assist in descending more quickly or maintaining a certain position in the water but does not influence nitrogen absorption or decompression risks.