The diving (diving) are those that allow human beings to remain in an underwater environment, mainly water, both fresh water and salt, and then mainly in the field of lacunar, river and sea. You can practice this activity with or without equipment and depending on the specific case it is called free diving or diving with ARA or ARO, in practice breathing systems or self-bound air, oxygen or gas mixtures, scuba diving in English (see SCUBA), systems that allow then immersion for long periods of time.
One can distinguish between recreational diving or technical / vocational training. The two types of equipment for diving are the open circuit system called ARA, the SCBA air dispenser developed by Jacques Cousteau as the Aqua-lung, and the closed-loop system that ARO, the self-contained oxygen created and used for the first time since the frogmen of the Italian Navy during world War II, more recently introduced and called Rebreather, Anglo-Saxon word which literally means rirespiratore, very sophisticated and complex, which can be closed circuit (CCR) or semi-(SCR), mechanical or electronic able depending on the type of reuse exhaled gas filtering it and riarricchendolo with oxygen missing, thus allowing to considerably extend the permanence in immersion by limiting the consumption of gAS and reducing the decompression thanks to the "Best mix "that provides at all times the same dive.
-100x100.JPG)
