Diving without bubbles
Blue Foot Diving is a rebreather orientated company. All of our instructors and most of our clients are now rebreather divers. We have a wealth of rebreather experience within our ranks. We teach sell and support the following rebreathers, Megalodon, Evolution, Inspiration, Kiss, Optima,Hollis Prism, LAR V, C96 Pro and now the Hammerhead rebreather. We have owned and taught extensively on all these units. We do not support the idea of any one rebreather being intrinsically safer than another. We wholeheartedly believe that all these units are good safe units and the key to safe rebreather diving is founded in instruction and diver attitude.
Firstly you must get good instruction. You will absolutely find this here at Blue Foot. Secondly and even more importantly is your attitude and how you continue to dive once we have set you on the right path. Be assured (health issues aside) that if you have an accident on a rebreather it will be your fault. There are no rebreather failures that cannot be predicted and you should have the skill and knowledge to recognize and remedy them all.
If you are interested in purchasing a rebreather, obtaining training or coming on an expedition with your unit please e mail or call us and we will be happy to talk to you about the options. OC divers are of course welcome on our boats and trips.
There is not a simple answer. There are many good rebreathers each with their own pro’s and cons, The unit you should purchase will depend on a number of thing including what you want to do and how much you can spend. Below is an article I first wrote 7 years ago, I have updated it some so hopefully this will aid you in answering this question.
Andrew Driver, January 2001Rebreathers are a contentious subject! There are certain groups and individuals who believe rebreathers are inherently dangerous. Others including myself believe they are safer for deep dives than Open Circuit (OC) far more fun, logistically easier and the future of diving. In my opinion, OC is dead for technical diving and rebreathers will be the SCUBA of choice for nearly all technical and many recreational divers. It may be another 10 or 15 years before general acceptance, but it will happen. If you are one of the growing numbers considering a rebreather purchase then read on because Rebreathers have arrived! There are simply too many advantages.
- Gas efficiency,
- Deco efficiency,
- Helium cost efficiency,
These advantages all add up to a better way to dive.
Rebreathers are certainly not a panacea for all diving ills and there is a down side.
- Discipline and good training is imperative.
- Time for mastery
- The diver
These shortcomings are not unique to rebreather diving and also apply to OC technical diving. However the weak link, the human factor can be magnified in the case of rebreather diving. Deaths in rebreather diving have occurred and will occur again as the units and diver methodologies evolve. These deaths in all instances will come down to the training, attitude, experience and ability of the individuals diving the unit rather than the unit itself. There are no rebreather problems that can’t be recognized and remedied by the practiced, educated and aware rebreather diver.
Open circuit diving is open to pretty much everyone. You can start a PADI course at age 8 and continue to dive until you are 80. Other than a desire to participate and reasonable health they are few things that should preclude anyone from taking part. For rebreathers this does not hold true. Not everyone is suited to rebreather diving. A greater degree of awareness and discipline is required. It is not difficult it just requires one not be complacent. If one seeds responsibility to the machine it can be fatal. Example. A diver had been using his Fully Closed Cirucit rebreather for only a short while. He had become comfortable diving his unit as it by now seemed simple and reliable. He decided he was capable to teach others while using the unit. He did not recognize the extra task loading required, became sidetracked by his students while preparing to enter the water and never turned his unit on. Hypoxia occurred and he died. The vast majority of accidents on rebreathers are often caused by something as simple as not turning on the Oxygen or handsets. However it is the subtext one should be aware of rather than the final cause. By this I mean it was more a failure of the diver getting ahead of himself, having too much task loading that caused this incident. Before you purchase a rebreather be prepared to dive it for an extended period before doing the type of dives you used to. Rebreather skills must be over learned. You must be aware that you are the weak link.
This article is not intended to explain how different rebreathers work. If you are considering buying a rebreather you should educate yourself on the different rebreather types and how they work. For a full explanation on rebreather modes use the information guide listed below.
Rebreathers have been around for a long time, a lot longer than OC. The idea was first conceived in the 17th Century with the first working system in 1878. A number of different rigs were used in the first and second world wars with units taking on their present design in the 1960’s The difference now is that commercial interests have further fueled their evolution. This has minimized the failure points and made them a viable proposition for the technical/recreational market. At this point, 10,000 technical and recreational divers are deciding that rebreathers are the tool of choice. Many more are looking to join the loop but are not sure of which rebreather make or mode they should buy?
This article will not tell you what unit to buy but rather what to look for and what to avoid when deciding on a purchase. So why should you listen to my opinion?
I have over 1500 + hours of rebreather time. I first dove a rebreather (LAR V O2 rebreather) in 1987 with the military. Since then, I have purchased 5 different rebreathers, a Cis Lunar, an Inspiration a Atlantis, a Megalodon a Kiss and a Hammerhead . I have dived at least 8 other rebreathers including the Mk15.5, The Prism, Dolphin, BMD, TP2000, CCR500 and others. I am an IANTD rebreather Instructor Trainer T for the most of these units.
I waited 18 months (on a 3 month promise) after I paid a deposit on the Cis Lunar before delivery. On receipt it didn’t work and I waited another 6 months before it worked properly. I received the Inspiration pretty much on time. I waited 12 months on a 6 week promise for a Megalodon. I have had more electronic failures than I care to remember. I have dived and supported rebreather trips around the world, in areas as diverse as the Arctic and Amazon. I have used them for Cave and Wreck diving and dived up to depths of 450ft. Although my rebreather purchasing experience has not always been positive the whole rebreather experience has and nothing could make me give up my closed circuit equipment and dive OC again!
From these experiences I have compiled a set of criteria, in no particular order (except for rule 1 which should always be at the top of any rebreather list) to aid in the purchasing of a rebreather.
Rule # 1. Training, Instructors and Diving attitude.
There have been a number of fatalities on rebreathers. In most incidences it always came down to diver error. The time to start good habits is with a good instructor. Skilled instructors, providing comprehensive training is important in all facets of diving, but even more so in rebreather diving. If you pay $5.00 for training you get $5.00 worth of training. You pay peanuts you get monkeys! Once you have completed training build experience slowly and never become complacent with your rebreather or your emergency skills. Consider renting a rebreather for your course. This way you will find out what rebreathers are all about before making the big investment.
Rule # 2. Learn about the different modes and models of rebreathers.
What type let alone what model of rebreather is hotly debated? Here is a quick précis of the modes. At the bottom of this article there is a list of web sites, videos and books that you can use to further educate yourself on the rebreather specific models.
There are 4 basic types of rebreather.
- The Fully Closed rebreather, such as the Inspiration/Evolution, Cis Lunar, Megalodon, Prism, Optima Orebro’s CCR1000, and MK15 series. (no bubbles electronically controlled)
- The Kiss rebreather (metering/ manual addition of oxygen No bubbles). Kiss rebreather, COPIS Meg,
- Semi Closed Passive rebreather. Halcyon, Halcyon 80, Odyssey, K3 and BMD, (Occasional venting of bubbles, gas addition keyed to respiratory need)
- The Semi Closed Active rebreather: Dolphin/Atlantis, Azimuth, Drager Ray (constant mass flow adds nitrox continuously bubbles every 5 breaths or so.)
I believe there are many well designed rebreathers and none of the models readily available on the market are inherently dangerous. All have points that could be improved and some will suit certain types of diving better than others. Many people find it hard to admit that the unit they paid 1’000’s of dollars for has shortcomings. Regardless of the unit you purchase, I guarantee there will be parts that you would like improved, removed or added.
Rule # 3 What will you use the unit for?
Buy a unit suited to the type of diving you are doing now and intend to do in the future. The Dolphin SCC rebreather is a starting point for many people because of the price point (around $2500-3300). This is not a good investment if you ultimately intend to dive beyond 130ft/40M want to dive for more than a couple of hours and enjoy the benefits of a fully closed system. Speak with people who have experience with the different types of rebreather you are looking at and are doing the type of diving you intend to do.
Rule # 4 Get as much information as you can.
Some of what you hear will be good and some poor… so be aware. Individuals who own or teach a particular brand of rebreather will naturally have a bias towards that unit. Take that into account when you absorb that information. Interview your potential mentors. Ask them about their total experience with regards toward rebreathers. Keep in mind that OC teaching experience is not relevant to rebreathers. SCC experience is not really relevant to CC (closed circuit) experience either. Another huge benefit with the learning curve is to have other rebreather divers in your local. Find out what other rebreather divers there are and consider units common to that area.
Rule # 5 What is the makeup of the company selling the unit.
A number of rebreather manufacturers have come and gone in the last 10 years. Some taking deposits with them into bankruptcy. Cis lunar has gone and returned. Biomarine has gone out of business, as did the manufacturers of the Odyssey (US), BMD (Canadian), UT240 ( US ) K3 (US) and Fieno (Japan). You can’t buy a new Mk 15 series unless you pay Carlton 50K. In some instances, there are cottage industries that service these units and do a good job of it. When you purchase a unit you may want to consider whether the unit is being made by 2 people in a garage, or if there is a company with assets and history behind it. Just because a unit is made in a home shop doesn’t mean it’s bad though! It just means they are far more susceptible to problems in production, maintenance and vagaries of the economy. Ambient Pressure Diving – an entity of AP Valves - (Really its AP Valves with changed names for legal purposes) the manufacturer of the Inspiration is far and away the largest manufacturer of FCC rebreathers, with shipped units numbering around 5,000 worldwide. AP Valves has been around for 30 years and it’s a fair bet they will be around for a while yet. Consider whether the manufacturer will be around in the next 4-5 years? What business does it have to keep it going.
Rule # 6. Will your unit have a second hand value?
You may decide you want to sell your rebreather, to trade up or to take up golf. Either way it would be nice to know you could sell it. Many units have a decent second hand value. A second hand purchase is a good option but buyers beware. Also be aware of the person selling the unit. There have been a number of scams on E Bay. Don’t pay the money until you get the unit.
Rule # 7 How many units have been sold.
Find out how many units have been sold and the history of those units in service. Reliability of electronics, reliability of parts, work of breathing, comfort, surface attitude, its buoyancy characteristics, and manufacturing failure points are all considerations. The best test for how these things stand up is for the units to be out there and dived by Joe Public, or Joe Military. If a unit has been dived by a large number of people you will get a better idea of its performance. Unless you are part of a design team for a rebreather it is not a good idea to be a Beta tester for a rebreather company. If you are diving one of the first 20 units produced by a company then in all likelihood you are a guinea pig. From experience it can be incredibly frustrating to wait months for a unit only for it to fail.
Rule # 8 Time your purchase.
A general rule of thumb! Anything you buy in the rebreather world takes 3-5 time longer to arrive than the manufacturer promised delivery dates. (actually it is much better now than that AS 2007). However, even with the most reputable of companies you may have to wait for months if you buy during the wrong season. Many people buy in spring just prior to the diving season. There are 2 shortcomings in this thinking. First, everyone is doing the same, so you may end up having to wait. Second, you are opening yourself to the temptation of diving beyond your limit. As a bare minimum (for the qualified OC Trimix diver) it is recommended that one does 25-30 hours on one unit with air at depths less than 30m/100ft. The next 25-30 hours with HE to depths less than 180ft/55M. If you buy the unit in the off season, you are giving yourself the time to build experience before the temptation of deeper diving appears.
Rule # 9 $$$ cost
Don’t buy the most expensive rebreather then go looking for the cheapest training. The best investment you make on a rebreather will be the money you spend on training. If you can’t afford it don’t buy it.
Think about what you are getting for your money. Does it have deco electronics? Do you have to buy a back plate and harness, BC etc
The figures below are approximate for exact details contact a dealer.
Fully Closed rebreathers.
- Evolution / Inspiration Vision $10k
- Megalodon $8.5K, COPIS $6k
- Prism $8k
- HH Rebreather $10.5 K
- Optima $7k
Semi Closed Active rebreathers
- Dolphin $4k
- Azimuth $5k
Semi Closed Passive rebreather
- Halcyon 80 $8.5K
Kiss style rebreather
- Kiss rebreather $5.5k
- COPIS Meg $6k
Rule # 10 running costs, maintenance.
Operational expenses are not much more than standard OC with most rebreather but there is always a chance you might get stuck with a big bill if you drop it or break it somehow. For individuals doing a lot of HE diving it can be considerably cheaper. You will also need to factor in the cost of Sofnolime/absorbent, maintenance, batteries, and training.
Rebreathers are not something you can afford to be cheap with once you have purchased it. For a FCC course expect to pay around $1,5000 for training and do minimum 5 day course with at least 500 minutes of dive time.
Always remember! The real issue with rebreathers is not the unit! The real issue is the training you receive, the attitude knowledge and ability of the diver using the unit. In essence you must rely on yourself. If you can’t do that don’t buy a rebreather.
Here is a list of useful web sites, books and video on rebreathers. Learn as much as you can before purchase.