What is the primary role of dive tables?

Dive tables are specifically designed to provide guidelines for safe ascent and decompression during scuba diving. Their primary purpose is to help divers understand how long they can stay at specific depths and how long they should spend ascending from those depths to avoid decompression sickness, commonly known as "the bends." By following the information outlined in the dive tables, divers can plan their dives safely, ensuring that they ascend at controlled rates and make any necessary safety stops to allow nitrogen absorbed in their bodies to be released gradually.

Dive tables take into account various factors such as dive depth and duration and then indicate ascent procedures that minimize the risk of nitrogen loading in the body’s tissues. This guidance is crucial for divers to prevent potential adverse effects associated with rapid changes in pressure and to enhance the overall safety of the diving experience.

The other options do not serve the primary function of dive tables; for instance, recording a diver's dive history is related to dive logbooks rather than dive tables. Similarly, calculating water depth and measuring temperature pertains more to various instruments used in diving rather than the use of dive tables.