What is the maximum allowable PPO2 for recreational diving?

The maximum allowable partial pressure of oxygen (PPO2) for recreational diving is set at 1.4 ATA (atmospheres absolute). This level is chosen to minimize the risk of oxygen toxicity while still allowing for the beneficial effects of using enriched air nitrox.

Oxygen toxicity can occur at elevated PPO2 levels, particularly when divers are exposed to pressures greater than this threshold for extended periods. By keeping the PPO2 at 1.4 ATA, divers can enjoy the advantages of reduced nitrogen narcosis and enhanced bottom times without significantly increasing the risk of toxic reactions.

Staying within this limit helps ensure divers remain within safe operational guidelines, which is crucial for their safety and health throughout their diving activities. This understanding is critical for divers as they plan their dives, manage their exposure to oxygen, and prioritize safety in their diving practices.