What should divers monitor when using EANx?

When using Enriched Air Nitrox (EANx), divers should closely monitor the oxygen partial pressure. This is crucial because the increase in oxygen concentration from using EANx can lead to a higher partial pressure of oxygen in the breathing gas. This increased partial pressure can elevate the risk of oxygen toxicity, which can have serious consequences at certain depths.

Divers must understand the Maximum Operating Depth (MOD) for the specific mix they are using to ensure that the oxygen partial pressure remains within safe limits. The MOD is determined by calculating the depth at which the oxygen partial pressure approaches the threshold that could lead to toxicity, generally considered to be 1.4 ATA for recreational diving. Monitoring the oxygen partial pressure enables divers to make informed decisions about their dive profiles and helps maintain safety during the dive.

In contrast, temperature changes, water clarity, and salinity levels are important for overall diving safety and environment awareness but do not directly relate to the specific risks associated with using EANx. Monitoring these other factors is beneficial for general diving conditions, however, they do not specifically address the unique considerations presented by using enriched air nitrox.