Scuba Diving International (SDI) Computer Nitrox Practice Exam

What is the main purpose of a dive computer?

1. To calculate maximum depth only

2. To track time spent underwater

3. To monitor nitrogen absorption and ascent rates

4. To determine water temperature

The correct answer is: To monitor nitrogen absorption and ascent rates

The primary function of a dive computer is to monitor nitrogen absorption and ascent rates. This is crucial for ensuring safe diving practices. As divers descend and ascend in water, they are exposed to varying pressures that influence how nitrogen is absorbed by their bodies. A dive computer tracks this nitrogen uptake by calculating the diver's exposure based on factors such as depth and time. It provides real-time data that helps divers avoid decompression sickness (DCS) by alerting them when it's time to ascend or when to make safety stops, effectively managing their ascent rates. This ability to continuously monitor and provide critical safety information is what distinguishes a dive computer from simpler instruments that only track depth, time, or temperature. Other options such as calculating maximum depth or tracking time spent underwater do not encompass the full range of safety features that a dive computer offers. While these functions are important, they are secondary to the primary role of monitoring nitrogen absorption and managing ascent rates.