What are the two main types of dive tables used for planning dives?

The correct answer highlights the two primary categories of dive tables essential for planning dives: recreational dive tables and decompression dive tables.

Recreational dive tables are designed for dives that do not require the diver to exceed no-decompression limits, enabling divers to safely ascend to the surface without needing to make decompression stops. These tables provide simplified guidelines for planning dives to ensure divers stay within safe limits, minimizing the risk of decompression sickness.

On the other hand, decompression dive tables are specifically used when a diver exceeds the no-decompression limits, requiring them to make controlled stops during ascent to allow for safe off-gassing of absorbed nitrogen from the body. These tables are more complex and take into account various factors such as total bottom time and depth to help divers manage their ascent profile safely.

This distinction between the two types of tables is critical for dive planning, as it ensures divers understand the risks associated with their dive profiles and can take appropriate measures to avoid potential complications.