What is the effect of altitude on EANx diving?

The correct answer highlights the significant impact that altitude has on diving with EANx (Enriched Air Nitrox). At higher altitudes, the atmospheric pressure is lower than at sea level. This reduction in pressure affects how nitrogen is absorbed and released from the body during dives.

When diving at altitude, the reduced pressure means that divers can experience increased levels of nitrogen in their tissues, which can lead to a higher risk of decompression sickness (DCS) when ascending. Additionally, because the allowable partial pressure of oxygen must remain below specific limits to avoid toxicity, the effective bottom time at altitude is less than it would be at sea level for the same mixture of EANx. Divers using nitrox at altitude must therefore be more cautious, revised to lower depths and shorter bottom times to reduce the risk of DCS.

Understanding these dynamics is critical for planning dives at altitude and ensures that divers employ appropriate dive tables or computers that adjust for altitude conditions. This way, safety is prioritized while utilizing the benefits that nitrox offers in reducing nitrogen loading during dives.