What is the primary reason for adhering to the CNS "clock" value limits?

The primary reason for adhering to the CNS (Central Nervous System) "clock" value limits is to minimize the risk of oxygen toxicity. When divers breathe oxygen under higher-than-normal pressures, such as during deep dives or while using enriched gas mixtures, the risk of oxygen toxicity increases significantly. The CNS clock tracks the duration and concentration of oxygen exposure, helping divers manage and calculate their exposure levels.

If divers exceed the recommended limits on the CNS clock, they can experience symptoms of oxygen toxicity, which may lead to serious health issues, including seizures and loss of consciousness. Monitoring the CNS limits is a crucial aspect of dive planning and execution, ensuring that divers remain within safe limits to avoid these dangerous effects. This vigilance not only enhances divers' safety but also allows for longer and more enjoyable diving experiences without the associated risks of oxygen toxicity.