The word scuba is short for self contained underwater breathing apparatus, and these initials were first formed in 1939 in the US Navy and referred to that of the US military diver’s rebreather sets. Just like radar, the acronym is so common that it is not capitalized and is instead thought of as being an ordinary word.
The modern scuba diving set consists of two distinct things and these are open-circuit, called aqualung in the European countries and the closed-circuit/semi-closed circuit also known as a rebreather. In the case of aqualung or open-circuit scuba diving gear review, the driver is able to breathe in from the set and out to waste.
This is simple equipment and is easily and cheaply manufactured though it is uneconomical when used with expensive gas mixes like heliox and trimix and most divers just use standard air consisting of 21% oxygen and 79% Nitrogen.
Further Scuba Diving Gear Review
On the other hand, the closed-circuit/semi-closed circuit or rebreather scuba diving gear review allows the diver to be able to breathe in from the set and returns into the set where exhaled gas becomes reprocessed to enable it to be fit to breathe again.
Because of the fact that as much as 80% of oxygen is still around in exhaled gas, it could end up being wasted were it not for rebreathers which use gas economically and thus enable divers to stay submerged for longer durations of time as well as making special mixes to use instead of the more complicated technology that may otherwise become necessary. The rebreather comes in three different variants including oxygen, semi-closed circuit and fully-closed circuit rebreathers.
There is a certain amount of misinformation that is being circulated by newspapers and television news which sometimes describes the open-circuit scuba diving gear as being oxygen equipment and this may be due to comparing it with the aero plane pilot’s oxygen cylinders.
More recently, however there has been increased acceptance of Enriched Air Nitrox (EAN) and almost every scuba diving gear review discusses the use of simple compressed air. Use of EAN having a higher percentage of oxygen allows the diver to stay underwater longer due to the fact that there is less nitrogen being absorbed in to the tissues of the body.
Another scuba diving gear review point that crops up is that of the twin-hose open-circuit scuba which is the first type of diving demand valve and was also used in SCUBA adventures like TV’s Sea Hunt. In addition, there are also cryogenic open-circuit scuba diving sets which have liquid-air tanks instead of cylinders.