We have all seen the images of divers gliding through crystal-clear tropical oceans, marveling at rainbow-hued fish flitting about on vibrant coral reefs. We have viewed them on TV, in movies or perhaps we have even had the privilege of witnessing the experience firsthand on a vacation at a tropical destination. It is this visual feast that draws many people to scuba, but there are other reasons for becoming certified and going underwater.

Among these are safety and the opportunity to see the underwater world that nondivers can only glimpse through a snorkel tube or from a boat. Most scuba divers are also drawn to the serenity and tranquility of floating weightless in an environment that is as close to outer space as most people will ever experience.

The essential scuba equipment includes a tank, (one or more) which holds compressed air. A device called a regulator reduces the high pressure of the air in the tank to breathable levels. A diving computer is often used to track dive times and depth, as well as to alert the diver when it is time to ascend to the surface. A submersible pressure gauge, or SPG, is also usually attached to the tank. This is used to monitor the amount of air remaining in the tank and is a critical piece of safety equipment, along with the air mask and scuba fins.

In addition to learning to use this equipment, scuba certification requires mastering 24 key skills. These include proper assembly and pre-dive testing of the scuba gear; entries and exits from the water; safe and controlled descents and ascents; buddy diving procedures; hand signals for communication underwater; and recognizing and responding to common dive hazards.