ARE YOU A CERTIFICATE DIVER USED TO CLASSICAL DIVING?

WOULD YOU LIKE TO DISCOVER A NEW WAY OF DIVING?

Do not exceed stop limits, reduce gas consumption (reuse most of the exhaled gas) and meet unparalleled wildlife without releasing annoying bubbles is possible!

LET 'S DISCOVER THE REBREATHER TOGETHER

If once the Rebreather were mainly the exclusive prerogative of the Technical Divers, now not anymore. In fact, thanks to new technologies, the new rebreathers are increasingly light, easy to carry and have sophisticated electronics to simplify their use. But let's take a step back for a moment .. what are the differences that characterize it and that make it a system so special and different from the traditional way of diving?

Almost all equipment used by recreational divers fall into a category called open circuit self-contained breathing apparatus (our beautiful tank and regulators). In traditional diving, during the expiratory act, the exhaust gas is discarded in the form of bubbles with each breath, hence the term "open circuit".

Anyone who has participated in a diving course knows that during a respiratory act a human being uses approximately only 5% of the oxygen (O2) inspired by compared to 21% present in the air. The exhaled air, therefore, still contains about 16% of oxygen which remains unused and dispersed in the atmosphere (obviously in H2O during a dive).

A rebreather on the other hand (literally re-breathe) is a gas recirculation breathing system that allows the user to retain, "clean" and reuse all or only one wall of the exhaled gas: that is, the unused oxygen.

With the term clean, we intend to eliminate (by means of a special absorption filter positioned inside the circuit) the carbon dioxide produced by the human body at each expiratory act as a waste product of oxygen consumption. All thanks to the fact that the gas discarded (exhalation) does not go into H2O, but returns to the circuit ready to be cleaned and reused.

Rebreathers can be classified into two main categories: semi-closed circuit SCR (from the English Semi Closed Rebreather), and closed circuit CCR (from the English Closed Circuit Rebreather), the latter are in turn divided between mechanical and electronic. The difference between the two types is in the principle of operation.

An SCR rebreather is a machine that is able to partially recycle what we exhale, eliminating the superfluous in the form of bubbles through a suitably calibrated overpressure valve. Not being able to recycle all the exhaled gas, they allow lower autonomies compared to a CCR, but still much higher than a normal open circuit. SCRs are generally equipped with a cylinder containing a mixture of Nitrox.

A CCR, on the other hand, is a machine that, in addition to having the enormous advantage of entirely recycling what we exhale, allows us to breathe a constant amount of oxygen (technically, constant partial pressure of oxygen). To ensure that this happens, the CCRs are equipped with two different gases, the first pure O2 which serves to enrich the gaseous mixture as the O2 is consumed, and the second gas commonly called "diluent" as it serves to dilute O2 because as we all know you cannot breathe pure deeply. The type of thinner used varies according to the maximum immersion depth expected. It can be air (therefore Nitrogen) or Trimix (O2, Nitrogen and Helium), as it partly determines the maximum partial pressure of oxygen, the narcotic level and the various decompression profiles. In addition to the reduction of decompression times, the CCR, by entirely recycling everything we exhale, ensure that the autonomy in diving is considerably extended, regardless of depth.

Last but not least, by not emitting any bubbles, no noise is produced, thus allowing a much less invasive approach to aquatic life. In fact, the fish are less frightened and come closer, to the delight of photo / video operators.

Finally, the CCR in turn are divided into mechanical and electronic, with the difference that in the first case the machine is “managed” by the diver, while in the second case it is the electronics and the relative software dedicated to do it. Generally the level of training for the use of these machines is decidedly more demanding than that necessary for an SCR, it is advisable to approach these machines once the technical training in open circuit is completed.