Scuba is a fun and exciting way to explore the underwater world, but diving involves many technical concepts and terms. Understanding these can help you become more confident with your dives, and better understand the amazing marine life you’ll encounter along the way.

scuba is an acronym for Self Contained Underwater Breathing Apparatus, and it refers to the breathing equipment that allows a diver to remain underwater for extended periods of time without having to return to the surface to breathe. SCUBA divers use a tank of compressed gas, usually oxygen and nitrogen, for diving, and a computer that monitors the diver’s nitrogen levels during a dive to prevent decompression sickness.

The 1-3 rule is a safety principle that scuba divers follow to avoid decompression illness and nitrogen narcosis. This rule states that a diver should never descend faster than one meter per second, or ascend faster than three meters per second. The 1-3 rule is designed to allow the body to adjust to the changing pressures of the water column slowly, and reduce the risk of these potentially dangerous conditions.

A rebreather is a type of scuba that recycles the unused oxygen back into the system by removing the carbon dioxide from exhaled air, and adding supplemental oxygen into the mix. Rebreather scuba allows divers to multilevel dive and spend more time underwater than what is possible with open circuit scuba, which is the most common form of scuba.