How does increased PPO2 affect the diver’s physiology?

Increased partial pressure of oxygen (PPO2) can significantly impact a diver's physiology, particularly through the risk of oxygen toxicity. As the PPO2 increases with depth or with the use of enriched air nitrox, the body's exposure to oxygen also increases. At levels greater than 1.6 ATA (atmospheres absolute), there's a heightened risk for developing oxygen toxicity, which can manifest as neurological symptoms or pulmonary complications.

Understanding this phenomenon is critical for divers because oxygen toxicity can have serious health implications. Managing PPO2 levels is an essential part of dive planning and safety, particularly when using nitrox mixtures that contain higher oxygen concentrations than air. It is vital for divers to stay within safe limits to avoid potentially dangerous physiological effects. While there may be other benefits to certain PPO2 levels, the association between increased PPO2 and oxygen toxicity is the primary concern that divers need to be aware of.