Central Nervous System Oxygen Toxicity occurs when partial pressure of O2 exceeds what level in a wet diver?

Central Nervous System (CNS) Oxygen Toxicity is a significant concern for divers who use enriched air or dive deep, where the partial pressure of oxygen can increase. The threshold for CNS oxygen toxicity is typically recognized around 1.4 ata (atmospheres absolute) of partial pressure of oxygen. However, for practical purposes and common guidelines within diving communities, 1.3 ata is frequently used as a working limit to reduce the risk of CNS toxicity.

When the partial pressure of oxygen reaches this level, there is increased neurological risk due to higher oxygen concentrations that can affect brain function. Symptoms may include visual disturbances, muscle twitching, and even convulsions in severe cases. By identifying and adhering to the 1.3 ata guideline, divers can minimize their exposure to these potential dangers while diving.

The other options present higher partial pressure values, which are above the commonly accepted safety threshold for CNS toxicity and could lead to increased risks if exceeded. Therefore, 1.3 ata serves as the protective benchmark in diving practices.