What effect does high oxygen concentration have on diving safety?

High oxygen concentration can significantly impact diving safety due to the potential risk of central nervous system (CNS) toxicity. When divers use enriched air (Nitrox), they increase the oxygen percentage in the breathing gas, which can be beneficial for certain aspects of diving, such as reducing nitrogen exposure and the associated risk of decompression sickness. However, at elevated partial pressures of oxygen, there is a risk of CNS toxicity.

This condition can lead to symptoms such as visual disturbances, seizures, or even unconsciousness, which can be particularly dangerous while underwater. The risk of CNS toxicity becomes more pronounced at depths where the partial pressure of oxygen increases as a diver descends. Therefore, understanding and managing oxygen exposure is crucial for maintaining safety during dives with enriched air.

While high oxygen concentrations may enhance some aspects of the diving experience and provide specific advantages regarding nitrogen levels and the risk of bends, the most significant and immediate concern is the potential for toxicity at higher pressures.