Deciding which unit is to be your first CCR can be a overwhelming experience. Keep in mind the joy of learning while searching out, compiling and comparing units. Having no in depth, long term experience on any ccr makes it difficult to assess a “tryout” dive on a particular unit. It takes a significant amount of time diving a CCR to recognize peculiarities or idiosyncrasies between units. Many peculiarities will go unnoticed due to subtlety. Some units may have shortcomings but the assets can outweigh their shortfalls. Most often the astute and practiced ccr diver can make up for many, if not all, shortfalls.By the end of a CCR course the diver is no where near intimate with a unit but has been trained and tested to respond to 4 major life threatening incidences that can occur on a ccr, how to identify and respond to them. I was 3 years diving CCR before I REALLY felt GREAT diving them. I’m not saying I did not enjoy the ccr dives prior to that, I did. I am saying I began feeling more comfortable than I ever dreamed possible after practicing for 3 years. I had begun to comprehend instinctively what the unit was telling me. Interpretation of the readouts and other signs / symptoms of failure or proper functioning became intuitive.Most divers choose a unit based on others they know diving a specific unit. Keep in mind the advice given is limited to what the person has been told or
experienced. Don’t be “sold” a bill of goods on hearsay.
Experience on a single unit does not qualify someone to critique another
. Discuss units with someone who is rated, owns or has owned the unit. Rebreather divers are considered “beginners” for the first few years and should have at
least 5 years to be considered more than that. Any information on a ccr not trained on or owned is 2nd hand at best.
Some may “talk up” a given unit because it is the only one they know, teach or sell. Everyone IS partial to the unit they dive!
If you discuss types with an instructor that teaches multiple unit types you will probably get an experienced, better formed and less biased opinion.
Most CCR divers only have substantial experience on a single unit, if that. Most experienced ccr divers (2 to 5 years
minimum
); feel it takes several years to begin to gain a thorough understanding of rebreathers. Separating perception and reality can be difficult, but consider additionally: misinformation, lack of knowledge, lack of experience and the “information age” that makes any new comer an “expert”. A fellow instructor I know, who teaches every major unit stated;
“
EVERY
unit has pluses and minuses.” Learn characteristics and system traits from someone with broad, lengthy experience in the field of ccr. Again, learn from someone who has trained, owned and dive the units and not someone who has “heard” or “was told”.
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| Chossing a CCR by Jeff Johnson ccr instructor |
I would like to point out here several items worth noting.
1)
“Beefier components
in most cases and circumstances is not required. I have never damaged a scrubber housing (of even the poorest quality) or a wrist unit so that it was not serviceable. Matter of fact I have never damaged one at all that I am aware of. This is not to say that you do not want a unit that has stronger components. I am saying it is important to weigh more than this quality in your decision making process.
2)
Electronics and decompression software
loaded into your unit is a major advantage. I know this because I dove without deco software on a unit for years. Having the software integrated is of great advantage in receiving real time deco updates and gives the diver the ability to maximize bottom times while minimizing deco. If you are the type that used a dive computer and especially a nitrox or trimix computer, you certainly should consider a ccr with that capability. Should you REALLY want to “keep it simple” stay with open circuit. Less is NOT better. Don’t try to save money and begin with a unit that represents the 1990’s and has no decompression software. For $1,200. additional at initial purchase you could have a unit that with an add on later will cost 3,000.+ additional. Having MORE information to base decisions on is a good thing!
3)
Scrubber duration;
the normal scrubber duration “recommended” and supplied with the “standard” units is approximately 3 hours standard rating.Is MORE better? Not necessarily. I use a 3 hour rated scrubber and have never been required to shorten a dive.I’ve heard it asked “why pay $8,000. for a rebreather you can’t stay under for 10 hours with? My response would be; “I have not seen anyone stay under for 10 hours at all, unless of course completing actual and serious exploration”. This question is a bit like asking “why pay 25,000. for a car that only has a 18 gallon tank when you can get one with a 25 gallon tank for
30,000?”. The 3 hour rule is the
recommendation
by the mfgs on almost every stock unit. All training agencies state plainly to follow the mfg recommendation and NOT to exceed it. They
also recommend throwing out chemical that has been partially used. So a larger scrubber can also mean more waste.What are you’re current dive times? I dive 300 fw + for 40 minutes + decompression, cave dives to 100 ft + for 3 hours and have never had a problem with scrubber duration. Will the dive boat you charter allow you to be down longer than 3 hours?Also remember: NO one is going to pay more for a rebreather that has longer duration capabilities and quickly admit to themselves or others, “I spent more than I should have and don’t even need the duration I paid for!” , that is simple human nature.
I get SO tired of the ccr divers of late that want to OVER analyze every little thing. If you buy a unit from one of the majors, you’ll get a very capable unit and
MORE important than all
the
hashing about, discussion and arguing is receiving good training. Don’t become the resident expert and never become complacent. EVERYTHING else is just conversation, theory and justification.How about getting OFF the computer and the “expert” analysis and get some diving in! THAT, is what I do and that is why I stay away from “the lists”.
4)
The manufacturer
; do they stand behind their product? Do they communicate quick and accurate information? What is the probable “turnaround” on a repair? What country is the manufacturer based in? Most major mfg offer good product for your money. But keep in mind the “hype” does NOT always substantiate purchase: eg: “simple”, “beefy”
5)
Business size
: Many small businesses simply will not survive a mishap in manufacturing or downturn in the economy unless they have a broad base of equipment types or large enough to soften a setback. How much is the unit you’re considering dependant on a single mfg staying in business?
6)
Support and Repair
: Is there a retailer support system in place to serve you and service the unit?a) One important factor is an honest self assessment;b) What type of diver am I? Recreational? Technical? Etcc) What type of diving do I plan on doing?d) What type of training am I willing to commit to?So look over the entire package. Don’t be “sold” a bill of goods over a single claim or point. It’s human nature to justify the decision one made is the correct one.Be aware that although on line chats and list can lay a basic foundation they can cause additional confusion as well. Those lists are also loaded with those “resident experts”. Most of us with actual experience shy away from the “lists”. This is not to say there are not some highly experienced ccr divers and instructors on these lists, there are. But they are few and far between that have lengthy experience and can tolerate the “know it all ” spectacular of the Internet lists. Seems the divers today know more than the instructors in this internet era!One thing is certain; CCR components are changing rapidly. We’ve all seen the rapid advancement of microprocessors in home computers, mobile phone technology, ipods and like electronics. This makes the future of CCR all the more exciting to me. CCR divers are making modifications to components and either share the concept or build and sell accessories. And there are many units currently in the planning or testing phase as well. This is an exciting time to be in diving and the changes and excitement will continue for some time. Keep in mind that whichever unit you choose, someone is most likely to dream up and produce for sale better, or improved after market component for your chosen CCR as well as for other units. The good news is that there is already a reasonable number of manufacturers that produce after market components that enhance the stock units produced and sold to the public.In general closed circuit rebreathers are more comfortable to dive. The breathing resistance can be as you are used to in your everyday life. This is due to the fact that the loop should remain at ambient pressure and there is no valve to “crack” on demand during the inhalation phase. The ccr delivers warmer gas to breath. The gas has a high level of humidity resulting in no “dry mouth” and as little as 100th of the gas is used compared to open circuit. Lastly your nitrox mix is delivered custom blended for the dive you make.If you enjoy learning and diving, you will undoubtedly enjoy rebreather diving! Email us about training on a rebreather today.
I have been diving ccr since 1999 & teaching CCR since August of 2003. I am qualified on 8 different units.I have heard so much “disinformation” put forth, albeit unintentionally, I felt i must as an experienced ccr diver provide this document to inform divers how to make a truly informed choice.
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