Enriched Air Nitrox (SC-EAN) Practice Test

Using nitrox, or enriched air, significantly impacts dive planning due to the unique characteristics of the gas mixtures involved. The correct choice highlights that dive plans must be adjusted based on the specific enriched air nitrox (EANx) mix being utilized.

Nitrox has a higher oxygen content compared to regular atmospheric air. This increase in oxygen concentration alters the maximum operating depth (MOD) and the no-decompression limits (NDLs) of the dive. Each nitrox mixture comes with its own set of MOD, which is the deepest depth at which the gas can be safely inhaled without experiencing oxygen toxicity. Additionally, higher oxygen levels allow for longer no-decompression times, potentially extending the duration of the dive without requiring decompression stops upon ascent.

Failure to adjust dive plans according to the EANx mix can lead to unsafe diving practices, such as exceeding the MOD, which can increase the risk of oxygen toxicity, or miscalculating the NDL, which can result in increased risk of decompression sickness. Therefore, a proper understanding of how nitrox affects diving parameters is crucial for safe and effective dive planning.