| Scuba, a common word, is actually an acronym for | | | | divers. |
| Self Contained Underwater Breathing Apparatus | | | | A person has to be at least at least 15 years old to |
| originated in 1939 to refer to US military diver's | | | | get the open water diver certification, in good health |
| rebreather sets used by the Navy. A Scuba set is | | | | and be able to swim 200 yards using any stroke, and |
| basically an independent breathing equipment, | | | | float or tread on water for about 10 minutes. Some |
| equipped with breathing gas that enables divers to | | | | of the most popular and biggest scuba diving |
| stay underwater for considerably long periods of | | | | certification agencies include PADI, NAUI, YMCA, |
| time. The Aqualung was the first modern scuba diving | | | | Scuba Schools International, and PDIC. These |
| equipment invented by Jacques-Yves Cousteau and | | | | organizations offer some of the best scuba courses |
| Emile Gagnan in 1943. | | | | and training instructors available. There is also a Junior |
| Scuba diving, which was initially intended for military | | | | Open Water Diver Certification for people between |
| and scientific use, has now become one the most | | | | ages 10 to 15, provided by agencies such as |
| popular recreational water sports around the world | | | | Bubblemakers, Scuba rangers, and SASY. |
| today. Children, as young as 10 years old, can now | | | | Basic scuba diving equipment includes accessories |
| get Open Water Diver Certification (junior) from | | | | such as the mask, fins, snorkel, weight belt etc. |
| various centers. Scuba diving can be a lot of fun for | | | | There are two main types of scuba sets - |
| people who love marine life, commonly used by | | | | open-circuit and closed-circuit. |
| recreational divers for fish identification, search and | | | | Most scuba divers use standard air - 21% Oxygen, |
| recovery, underwater photography or videography, | | | | 79% Nitrogen - for their open-circuit scuba sets, |
| etc. However, since scuba diving is a fairly dangerous | | | | which is much more cost-effective than using |
| sport, it is recommended by experts to take | | | | mixtures such as heliox and trimix. The open-circuit |
| necessary lessons or certifications before pursuing | | | | scuba set (also known as Aqualung) itself is quite |
| the sport as a hobby. | | | | simple so is also cheaper and more popular than other |
| Commercially, scuba diving is used for underwater | | | | types. Basically, the user breathes in from the set |
| constructions such as oil platforms, bridges, docks, | | | | and out to waste, with the gas cylinder worn on the |
| dams, nuclear power plants and other coastal | | | | back. There are 2- and 3 backpack cylinders |
| structures. Scuba diving, which involves scientific | | | | open-circuit scuba sets available. |
| surveys and inspections, is known as scientific diving, | | | | Closed-circuit scuba sets use rebreathers. In this |
| which is exclusive to scientific purposes such as | | | | system, exhaled air is reprocessed by the rebreather |
| underwater experiments and underwater | | | | to make it fit for re-inhalation. This can be very |
| archaeology. As for the military, scuba diving has | | | | economical for people who need to take long dives. |
| been put to use for naval ship repair and | | | | The three types of rebreathers include oxygen, |
| construction, and includes specialized diving divisions | | | | semi-closed circuit and fully-closed circuit rebreathers. |
| such as explosives ordnance disposal and combatant | | | | |