What is crucial to manage during deep dives regarding dive time?

Tracking total dive time for nitrogen build-up management is crucial during deep dives because it directly relates to the risk of decompression sickness, also known as "the bends." As divers descend and spend time at depth, nitrogen from the breathing gas becomes more soluble in the body's tissues. The longer a diver stays at depth, the greater the potential accumulation of nitrogen.

To mitigate this risk, divers must accurately monitor their total dive time. This includes the time spent at the planned depth as well as considering any safety stops needed for ascent. If divers exceed safe limits without properly managing their exposure to nitrogen, they may face serious health issues upon ascent due to the rapid release of nitrogen from the tissues.

While syncing watches with other divers can be helpful for coordination, it is not the primary concern regarding nitrogen management. Measuring depth is important for safe diving practices, but it does not provide the full picture of nitrogen uptake like total dive time does. Similarly, while monitoring temperature changes can be useful for assessing environmental conditions, it does not directly impact nitrogen loading in the body.