Scuba Diving International (SDI) Computer Nitrox Practice Exam

When is a dive computer particularly useful during a dive?

1. During free-diving sessions

2. When assessing surface conditions

3. In managing nitrogen levels and ascent rate

4. When planning dive locations

The correct answer is: In managing nitrogen levels and ascent rate

A dive computer is particularly useful in managing nitrogen levels and ascent rate because it continuously tracks the diver's depth, time spent underwater, and the breathing gas being used. This real-time data allows the dive computer to calculate the residual nitrogen in the diver's body and display no-decompression limits, which are critical for avoiding decompression sickness. Additionally, it monitors ascent rates, ensuring that the diver ascends slowly enough to allow nitrogen to safely off-gas from the body. This capability provides divers with essential information to make informed decisions throughout the dive, promoting safety and enhancing the diving experience. In contrast, free-diving sessions don't typically involve the use of dive computers, as they are primarily designed for scuba diving. Assessing surface conditions is important but does not rely on the specific functions of a dive computer, which is focused on managing in-water parameters. While planning dive locations is essential for dive preparation, it occurs before the dive and does not pertain to the real-time monitoring that a dive computer provides.