What are two major considerations when using a Nitrox blend in diving?

Using a Nitrox blend in diving involves critical considerations that directly affect safety and dive planning. The two major considerations are Maximum Operating Depth (MOD) and Maximum Oxygen Exposure (MO2).

Maximum Operating Depth (MOD) pertains to the deepest depth at which a specific Nitrox mix can be safely utilized while avoiding oxygen toxicity. Each Nitrox blend has a different percentage of oxygen, influencing the maximum safe depth. Higher oxygen concentrations have lower MODs due to the increased risk of oxygen toxicity as pressure increases underwater.

Maximum Oxygen Exposure (MO2) relates to the total amount of oxygen a diver is exposed to during a dive, factoring in both depth and time. Volumes of oxygen breathed at certain depths can accumulate to exceed safe levels, leading to potential oxygen toxicity. Understanding and tracking MO2 is essential to limit exposure and ensure safe dive practices, particularly on multiple dives or prolonged activities.

These considerations are fundamental to safely utilizing Nitrox, unlike the other options, which focus on aspects that do not directly impact the physiological risks associated with high oxygen levels during dives. Considering visibility and temperature affects dive comfort and environmental factors, but they do not influence the risk associated with oxygen toxicity. Similarly, while equipment weight, air consumption, safety stops, and ascent rates are