There are many different rebreather manufacturers in the world and everyone will tell you that their own units are the best that are available. You’d expect that though wouldn’t you?
The problem with rebreather manufacturers is that once that they have designed and built their rebreathers they then need to test them.
Testing is expensive and you have to initally test it by diving it yourself. It is possible to use breathing machines that simulate breathing and carbon dioxide production these machines can be pressurised to depth but they are very, very expensive to use and almost impossible to buy for the fledgling manufacturer. Without the breathing simulators the only choice is to take it and dive it. Once the manufacturer is happy with their own test dives they then produce a small numer of rebreathers and sell them. The divers that buy them are aware that they have a new unit and that there may be teething troubles and that in effect they are undertaking a form of test. This is known as “Beta testing”.
rEvo rebreathers invested in their very own breathing machine known as an “ANSTI” machine. There are very few of these machines in the world and the benefit that it has to a manufacturer is that tests can be undertaken in a controlled enviroment and data collected digitally. No divers are at risk in testing equipment.
rEvo don’t just test their rebreathers in the ANSTI machine but they also test the carbon dioxide absorbant materials to ensure what they recommend is the very best available.
The tests are carried out in all conditions and there is nothing left to chance. Before any new rEvo leaves the factory it undergos a 120 different tests.
The look of the rEvo is quite different to any other rebreather and that is because it uses two carbon dioxide abosorbant material canisters instead of one. The benefit of using two canisters is a topic in it’s own right and you can read more about that here.
The owner and designer of rEvo Rebreathers is Paul Raymeakers and he doesn’t just produce rEvo rebreathers he is also an avid diver of them. Unlike many other manufacturers, when there is a chance of a rEvo being used in a record breaking dive, Paul doesn’t expect some other diver to attempt it, he goes himself on his own rebreather that he designed and manufactured. He has the upmost belief in his product and this was apparent when he took a standard rEvo to 212 metres in Dec 2009.
Paul is not simply a manufacturer who just wants to sell units, you can always contact him with any questions, problems or suggestions and he always replies. It’s a really big factor for many divers who have trusted their lives to a rEvo rebreather.
Cells
In a perfect world we only need one cell. However in reality we cannot trust that one cell is giving the correct information so we need more cells to verify. Two cells is no good because if you have one good and one bad you don’t know which is giving the correct information and which is not. You cannot be sure which is correct.
Most rebreather manufacturers have decided that three cells is the right amount because if you have three cells you can take the two closest cell readings as being correct and rule out the remaining cell. That works fine but what if two cells fail together? Research has shown that cells of the same batch that have the same dive history are far more likely to fail together. This means that three cells fitted at the same time from the same batch gives a higher probability of two cells failing together. Thus the two failed cells will out vote the good cell.
rEvo rebreathers can have up to 5 cells. This gives the diver the information that he needs to make an informed judgement on the readouts from the Cells. The diver will then know if there is a cell going out of range and the decisions are left with the thinking diver who understands what is happening and not to the programming on a computer.
There is a nice article on cells available to download here
Need More Information?
For more information on rEvo Rebreathers at Tekdeep please do not hesitate to contact us
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