When students came in or inquiring about doing their first CCR class, they often came in with many questions and misconceptions as well as differences in expectations. I normally offer a free introductory Q&A consultation session before they actually decided to sign up for the course. This way we can be sure they know well ahead of time what to expect in the course and what rebreather diving is really like. Some people may decide CCR is not for them after all which is completely fine, because in reality we have to accept CCR diving is not for everyone.

There are some common mistakes or misconceptions about getting into CCR diving or when doing the course, which I will try to list some of them and explain here:

Choosing the rebreather that is right for you: Most students divers don't realize rebreather training is unit specific as well as additional training is required for different types of machines. Also, they have no idea what should they look for in choosing a rebreather, thus they tend to have more questions than answers that they could find easily. General public "non-expert" opinions also vary considerably, especially when it comes to choosing an instructor or which machine to dive on. Sometimes they may end up regretting their decisions, therefore it is really up to us the instructors to give sounded and unbiased advice and to give not only the good side but also the bad side about diving a rebreather.

For first time rebreather divers, it is always more difficult to learn also more time is needed to master it than they first realized. Coming from open circuit , even for more experienced divers or OC instructors, you really do need to put in more time and effort to learn the new way of controlling the rebreather and buoyancy. The way you used to control buoyancy in open circuit actually works against you, and yes everyone becomes a beginner again. The enjoyment of diving a rebreather usually doesn't come as quickly as they wish to have. Often only towards the end of the course or even after the course with more practices. Don’t get discouraged early and be persistent because once you get there it is totally awesome!

Don't leave that loop open… it is a very easy mistake, in the beginning, to forget to close the mouthpiece when not in use., whether it is on the surface or on entry. Causing flooding of the unit is a serious easy mistake.

Yes, you do have to carry bailout tank(s), even for shallow dives. The proper safe way of diving a rebreather, in terms of weight, you usually carry just as much or more gear into the water than many try to let believe otherwise. Don't let them misguide you about have only a lightweight unit on your back, and you can stay for hours to great depths underwater.

Commitment - Many people don't realize the commitment you need to have to dive and own a rebreather. The pre-dive / post-dive assembly, checks, time, and care that is required. The regular maintenance and cleaning, also the need to dive it often and to stay current and active. A rebreather is much more complicated with far more safety procedures than open circuit diving, you really have to get very intimate with it and dive it as often as possible and try stay up to date. It is the only safe way to be a CCR diver. It is not some qualification that you have by taking a course a couple of years ago and showing off with a card to your friends for it.

I get these questions asked a lot by many open circuit instructors thinking of taking a CCR course because they think it could be an extra revenue stream for them to able to teach it, and often they inquire how to become a CCR instructor as quickly as possible. First, you can not become a CCR instructor just because you are a scuba instructor with a certain agency and by taking just one course. Second, the time, money and effort invested in becoming an CCR instructor is much more than they realized and if you are not truly a CCR believer, active CCR diver, and be passionate about it, you should not walk down this path.

• Edmund Yiu

Yes, without question due to the extended bottom time, efficiency, vastly reduced task loading to permit safe scientific research at various depths, and the ability to interact with nature. Most important, however, is the type of rebreather and those you dive with, both of which needs to be fit for the job.

To be specific, the Divesoft Liberty is particularly fit for use in scientific diving field research for the following reasons:

• ▪️ The electronics of the rebreather provide the appropriate gas mix at any one depth and time (provided you have the correct diluent). This reduces task loading of manual operation.

• ▪️ The use of CCR per se significantly reduces the amount of OC cylinders that are necessary to equate the necessary dive time for a particular research task at depth.

• ▪️ Enables a lot of work to be conducted over a range of depths without gas switches and, thus, additional task loading.

• ▪️ The diver typically has sufficient gas and redundancy to attend to additional unexpected tasks, particularly when troubleshooting research equipment or documenting wildlife.

• ▪️ Facilitates ecosystem exploration in a safe and timely manner, especially with the high level of redundancy.

• ▪️ It is quiet, and thus, does not startle marine animals.

• ▪️ Enables one to develop an objective gestalt of the natural environment, which is something that is unattainable from an ROV/robot.

• ▪️ Ability to focus on the job using a fault-tolerant unit in high confidence that it is not 'out to get me'.

• ▪️ Warm breathing gas for dives of several hours’ duration – comfortable and practical.

• ▪️ Using OC instead of CCR is like using a single abacus to calculate multivarious statistics!

Finally, necessity being the mother of invention; the workmanship, rigorous pressure testing, and Sonia-proof materials and design 😊

• Sonia J. Rowley

I believe CCR diving is not for beginner divers. A good understanding of diving physics, physiology, dive planning and gas management is as important as a good level of advanced diving skills (perfect buoyancy control, fin kicks, safety procedures and at least one stage cylinder usage).

Additionally, a diver needs to be patient and passionate about the diving they're doing. Usually, the desire for new adventure and exploration creates a very good starting point.

• Petr Slezák

When I first started to use a fully closed CCR, the problems were abundant, most of them related to the support of the requested "gas filling" needs. In fact, no O2 facility was easily accessible, we are talking around 1998/99, Sofnolime was only available in the UK, none in the EU in those days.

I also had problems with the sharing of information and most of all dives. People didn't know anything about rebreathers, and I was quite alone. If my ego was more than happy about people asking me: "What is this diving equipment" I had difficulties sharing and learning, not only from my mistakes but from someone else experience/mistakes. I believe that this sort of loneliness was the main problem in my early CCR diving career.

• Edoardo Pavia

For the amount of trimix wreck diving that I do, in the end, it saves me a lot of money that would be spent on helium. The wreck trips that I do join in on are usually 5 to 6 days trips. The tanks that we would be using are all filled before the trip, that way we have a nice enjoyable trip.

• Bruce Konefe

Well, straight away the word Sidemount, means a lot more than many people usually think. It was never a fad, it was essentially 'a means to an end' and a choice! The point of Sidemounting equipment was fundamentally for versatility, accessibility and safety. This meant that the equipment could be handled in sometimes more demanding environments, lifted, lowered or carried with more ease, transported and be used as a form of transport to suit the needs of the diver and the team.

For me, the element of removing the weight from my back (particularly lower spine) enables me to dive more comfortably for longer both in hours underwater and over many consecutive days/ weeks/ months.

The Divesoft Liberty Sidemount has been a game changer for me, in terms of dive for dive, in comparison to its Backmount brother. Having everything on the Liberty Sidemount constructed into a compact 11ltr ally/ 12ltr steel cylinder sized frame, including the diluent and oxygen sources, means I’m basically diving in Sidemount as I would ordinarily with my bailout 11ltr/ 12ltr cylinder on the opposite side.

My buddy Backmount Liberty diver has to wear the same bailout cylinder as well. So, in essence, it’s similar to diving in two-cylinder traditional Sidemount configuration. It can also be used as a manual CCR, electronic CCR or bailout CCR.

One of the most intrinsic benefits to diving the Liberty Sidemount, is that it's almost neutrally buoyant in the water, allowing me to take it abroad and dive in a wetsuit using an ally80 as bailout. Then take it to colder climates, wearing a drysuit and swap the bailout for a steel 12ltr and simply shift a piece of weight on my harness. It couldn't be more simple or versatile.

• Garry Dallas

We can really say 'Back to the Future!' thinking that 25 years ago we already had a glimpse of the future with the CisLunar mk5.

We had to wait until recent years to have something similar back on the market. I don't think rebreather technology will change much, in the end the basic concept is the same for every unit: filtering the CO2 and maintaining a breathable mix.

We now have lighter units thanks to the improvement of materials but eventually, the weight we need to carry in order to conduct the dive won't change.

We have smaller units but the autonomy is limited unless we connect to outboard sources, but then we have non-independent units. We will see changes in shape or improvements of the electronics but I think the real step forward would be the gas analysis, the improved development and use of different gas sensors for O2 and CO2, to be more accurate, and more reliable.

Divesoft did a huge job with the CCR Liberty adding He sensors and working on the software to get redundant O2 readings and this, among other unique features, sent the Liberty towards the top of the always growing pyramid of CCR manufacturing.

Although, rebreather diving is not only about SCR or CCR building, the human interface plays a big role in the equation as well. Rebreathers did see a huge expansion over the years, and they are still growing in numbers and variety. Training and divers' behavior followed close but not at the same pace. This is where we all have the opportunity to improve and get better.

Divers now-a-days are more aware of the use of these fantastic toys because knowledge is generally more accessible. There is still the tendency to rush the experience, taking shortcuts, and risking leaving too much room for mistakes. Oversight and distractions with rebreathers can easily lead to dire consequences.

I think we've reached a point where it would be more important to focus on the human side more than on the technological side.

• Nadir Quarta