Technical Diving International (TDI) offers courses for the diver looking for something a little more extreme. Courses include Introduction to Technical Diving, Nitrox, Advanced Nitrox, Cavern and Cave, and CCR.

Ben K. and Daniel were doing their Tec Deep Instructor Course last week. The Sea was a little rough, boats were incredibly busy, but looking at the pics they had a great time with Tec Diving Instructor Ben Reymenants.  On the 11th of January they actually saw a Manta Ray at their deco stop….and it wasnt a small one either. Their first dive was to 50 meters and Daniel was itsy bitsy narced.

Ben K. is doing a few more days of diving in Phuket. The 12th, today, they are diving Racha Noi dive site and Racha Yai dive sites. Tomorrow Ben K. is diving with our one and only Ian.

Deep tec Diving

Ben and Daniel Tec Deep instructors

CCR OR NOT TO CCR, I often get asked the question from technical divers whether they should go the no bubble way.

So should you or not? I thought I’d put down my two cents worth and get some of the pros and cons out of the way.

1) Price Tag of the CCR:

INspo divers on try dive

Take it or leave it; a closed circuit rebreather, CCR, is an expensive piece of equipment and it should also be handled like that. Depending on currencies and import duties you are looking at 6,000-15,000US$ for a closed circuit rebreather.

Where does this ridiculous price come from and what’s the difference? You should know that there are 3 types of rebreathers; the semi closed rebreather, SCR, injecting a chosen gas at a set rate into a breathing system. This is a safe choice as mechanics and electronics are limited and so is the price.

Then there are the manual closed circuit rebreathers. These units are just like the semi closed units based on a constant flow (regulated my an injection nozzle, or mass flow orifice) but this time it is pure oxygen instead of your bottom gas.

Oxygen can kill you when levels are too high or too little, hence, a close monitoring is crucial. Monitoring is established through 1-3 oxygen sensors giving a signal to a submersible handset, giving you the partial pressure oxygen readings of what goes actually into your lungs. The diver can then choose to manually inject more oxygen should a higher partial pressure of oxygen be desired. The injection nozzle is just there to keep survivable oxygen content in case the diver forgets to manually add oxygen. These units, or manual CCR’s (MCCR) are a bit more expensive than the semi closed rebreather because of the electronics. Plenty of divers add a second monitoring system as redundancy or an inline decompression computer that adds monitoring redundancy whilst giving on the fly decompression requirements readouts.

The last family is the ECCR or electronic rebreathers. The diver chooses a pre-set oxygen partial pressure and the unit maintains that specific pressure, called a set point. This requires again electronics and a solenoid valve, a small electronic gas valve, which adds small bursts of oxygen to maintain the set point. Because the user now totally relies on electronics, these units always have redundant displays. In case of malfunction, the user can still ‘fly’ the unit manually. Like the MCCR’s , many CCR divers replace the secondary handset with an inline decompression computer which acts as oxygen monitor and decompression computer.

2) Dive Price once you have the CCR:

Once you’ve bitten through the bullet of buying a machine, it won’t dive by itself. Just like an expensive racecar, it needs some ingredients to run.

The ingredients are:

• 1 tank of oxygen
• 1 tank of diluent (bottom gas, can be air or a helium mixture for deeper dives)
• quantity of carbon dioxide absorbent. This is the chemical, which will ‘scrub’ the co2 out of your exhaled breath so it can be re’breathed after the machine added the oxygen you’ve just used.

Rebreather CCR Diving

An oxygen fill can cost anywhere between 5 and 15 dollars. The tanks are small and depending on the type of diving you do you can spent one to 3 dives on one tank. The same goes for the diluent tank. Air is cheap and a fill can cost you between 3-10 dollars. The helium will cost far more (see below)

The chemical, scrubber, is not cheap either; 2pounds or 1kg will cost you around 10$ and most units hold between 2kg and 4 kg (4-8LBS). A rough figure is around 1 hour per kg of scrubber material. So, just like with the tanks, this should be refilled after a day of diving

And then you’re not even on the dive boat yet… most operators will not give you a discount because you’re not breathing as much gas as the open circuit divers. You might as well take full advantage of this and take a bail-out tank with air since it’s paid for anyways and rebreather don’t always function like they should

3) Diving the CCR:

So, adding all the costs up, you’re looking at 65USD for just your CCR supplies on that 5 star liveaboard plus your diving. If you are fortunate and can buy all of those at cost price, this figure can drop to 30$ for your 3-day dive day, still more expensive than open circuit.

Preparing a CCR is not as straightforward as strapping a BCD and a regulator to your scuba tank. Just like a plane, there is an entire checklist a diver needs to go through, setting up his unit. Novice CCR divers will easily spent an hour prepping their unit for the day, while seasoned CCR divers might be able to do this in 20minutes. Prior to every dive, a brief checklist needs to be adhered to as well, taking again 5-10minutes. Failure to do so has resulted multiple times in death, even with experience CCR divers. Complacency kills!

4) Legal issues:

If you are teaching open circuit divers or simply diving alongside open circuit divers, the first thing you need to ask yourself, is if you can help them in case of an out of air emergency. Obviously you have though about your own bail out options should your unit fail. But is there enough of this to help a buddy CCR diver or an open circuit diver?

This is one of the reasons why it is not allowed by many agencies to dive a CCR while guiding or teaching other open circuit divers; simply because they might be confused of what gas source to breathe from when they are hanging all stressed out in front of you, giving the out of air sign.

When diving as a dive professional in European waters, there is the CE tag. Half of the CCR’s today on the market have put the time and money to obtain that CE mark, allowing CCR instructors to wear their unit during their profession. Check it out if that is your scope

5) Trimix and CCR:

Plenty of Trimix divers ask me if it is cheaper to dive a CCR on Trimix rather than on open circuit. Yes it is…

But only in the long run. If you’re a weekend diver and planning on purchasing a CCR just to save on helium costs, then don’t. The training required, the number of dives and the cost of a unit well outweigh the few hundred dollars spent a year on helium.

If you are normally diving a 80’s twinset with a 50% helium mixture, then you would save around 100USD per dive. As a rough figure, you would need a 100 Trimix dives to have a break even. This does not take into account the training (+/-5000USD) and the spare parts, excess weight when traveling and your bail out gasses, which many will dispute that they are re-useable. Try telling the local dive shop in Egypt to keep your stage bail out gas until next year.

So why dive a CCR, rebreather?

Simply because, once you get through the training and the endless adjusting and fine tuning, a CCR gives you a tremendous feeling of freedom; the bubbly noise is gone, you’re breathing warm moist air as opposed to cold dry gas, you have a seemingly endless gas supply and you know that your machine is mixing for you the perfect mix at every depth, allowing for a maximum bottom time with no or limited decompression requirements. The high partial pressure of oxygen in the shallows will leave you feeling les tired and less dehydrated after diving.

The lack of noise from the bubbles and regulator will let marine life get closer to you.

Lastly, if an o-ring blows out of your open circuit scuba tank; you have a few seconds left to either locate your buddy or start heading towards the surface before gulping down your last breath. In case of total gas loss, a CCR will leave you quite a bit of time before the levels in the breathing system drop to a dangerous level. But the again, if you take the loop out of your mouth, it will fill up with water, rendering the unit useless.  Some systems now have a drain valve, so limited amounts of water can be drained in case of a flood.

So, to CCR or not to CCR?

Diving CCR needs serious dedication, on a financial level, training level, bit also afterwards on maintenance and discipline level. The rewards are there, although you might not appreciate them in the beginning, since the first dive on a CCR will leave you feeling as an absolute novice diver with limited buoyancy skills… Still, I believe CCR’s are the way forward into diving and the future of technology will make safer and more reliable humans, sorry CCR’s

Ben Reymenants, Megalodon Air Decompression Instructor Trainer and Trimix Instructor Trainer

In the last year, I lost count in how many times I was asked the question; why does one need sidemount during open water dives?

 The reasons for sidemount seem obvious when engaging in overhead activities such as narrow caves or wrecks. Here, the sidemount system provides a more streamlined setup for the diver, allowing him or her to pass through smaller restrictions, otherwise not accessible with having a scuba cylinder conventionally mounted on your back. The sidemount system also allows to unclip the tanks and push them ahead of the diver. This way, the divers’ profile is even more decreased and passages with a diameter as big as the diver or his two tanks can be passed.

Sidemount and Solo Diver

This system has actually been in use since the sixties when British cave explorers needed to carry tanks in order to pass flooded sumps in otherwise dry cavesystems. Their climbing harness provided for ample attachment points for the cylinder.

But what about open water dives? Let’s start with the definition of sidemount first;

A typical sidemount setup would be comprised of a harness, sporting a series of stainless steel d-rings and usually some sort of buoyancy device. The buoyancy device can be replaced by the buoyancy the divers’ drysuit gives.

The diver will carry a series of tanks, that are equipped with webbing to hold two clips, on near the cylinder neck and one lower down –  This is how the cylinders are attached to the diver  – One tank on each side, with the tankvalves tucked under the divers’ armpits. Most harnesses have a additional bungee to keep the tanks closer to the diver. Each tank has it’s own regulator and a pressure gauge on a very short hose. One regulator will typically have a 2meter hose to ease air sharing in emergencies. The other regulator comes with a short(er) inflator hose if required.

Solo DIver on Sidemount

Any seasoned diver will see the advantages of such a minimalist and streamlined setup; fighting against a current becomes easier because of lesser drag, but the risk of getting your regulator or tank valve entangled in nets of fishing wire is reduced to nil.

But the true selling point of sidemount for open ocean diving would be the comfort;

-The diver does not need any longer walk on the dive-deck with a heavy tank on the back, instead the tanks can be clipped on last minute, or even when in the water. Coming out of the water, the tanks can be place on the side of the water or passed onto dive-crew before exiting the water. The only equipment the diver is carrying is the harness.

This has poses significant advantages for divers that do not have the physical ability to stand up with a heavy cylinder(s) and walk their way to the water.

-Secondly , the trim of the diver improves instantly. The trim is the divers’ position in the water. Pull an imaginary rope from the divers’ feet to the divers head. This is the axial line, which should be as horizontal as possible to make for a smooth glide through the water. Divers with a ‘good trim’ have their body perfectly horizontal with only the legs bend at the knees and feet/fins sticking up vertically.

 A normal diver has the centre of gravity high up because of the weight of the cylinder on his/her back. This makes that the diver needs an active effort to stay in balance. With the sidemount setup, this centre of gravity is lowered down to slightly below the divers’ chest because of the tanks hanging on either side of the diver. Think of a sailing ship. The tanks are the ballast or the kiel of the ship if you like.

- lastly, there’s the access to the tanks; divers can readily reach either tank and see pressure, open or close the tank valve or spot any leaks.

Divers can choose to dive with only one cylinder attached to the harness. This is a popular option when using DPV’s (diver propulsion vehicle) or underwater scooters.

Technical sidemount divers will carry 3, up to 6 tanks to provide extra decompression gas or redundancy overall.

Solo DIver

Mostly, a sidemount diver will have two cylinders, strapped to either side. The cylinders can be smaller ( S-40’s / 7litre) than the more common S-80’s  / 11L , but whichever size is decided upon, the diver will carry two.

This is a major advantage , since the diver is now fully redundant in his/her gas supply and moreover, has full access to regulator and tankvalves for problem shooting. With regular scuba setup, the diver is totally reliant on the buddy to aid in any malfunctioning equipment.

The Solo diver/ self-reliant diver is an individual with a passion for diving, who collected an ample amount of diving experience, and who wishes to engage in diving activities without a buddy. This may be out of free will, or simply because there is no-one available or crazy enough.

Think of photographers or videographers or marine biologist finding them selves alone when they can’t find a buddy that wants to spent hours under water to shoot or collect a rare species.

Plenty of dive professionals would love the idea of diving by themselves for once, without the responsibility of having a group of novice divers behind them to herd.

Several training agencies have come out in the past decade with courses for divers wanting to dive alone. The prerequisites are; sufficient diving experience, self help under water and carry life-saving redundant equipment. Besides a spare mask and depth gauge, there needs to be a reserve gas supply to make it back to the surface in case of a major gas loss. Typically a diver will buy a small pony bottle or spare air to suit those needs. These don’t come cheap and are a menace to take on planes because of safety and weight.

Last year I started offering the Solo Sidemount diver packages to experienced divers. My customer base exists out of dive instructors and underwater videographers.

The course comprises of a generic sidemount course, with the focus on the diver being able to help himself out of most imaginable situations; o-ring blow out, entanglement, loss of vision, swept away in the blue by a current.

The course typically takes 2-3 days and at the end of it, the divers carries home a dual certification; that of a sidemount diver and a solo or self-reliant diver.

All the equipment required for the course is included, but the diver can opt to buy his/her own gear. The course enables the diver to step on any dive boat and use the tanks provided by the dive operator.

Is it expensive?

Let me first outline the equipment a standard sidemount (open water) diver would carry;

• Sidemount harness / BCD
• Set of bungees
• Two regulators, basic, with first and second stage and a small pressure gauge on a short hose
• Pouch containing spare mask, cutting device, back up depth gauge/timer, dive tables
• Spool or small reel
• Surface marker buoy
• Compass
• Computer
• Cylinder rigging set (cylinder band and a looped rope with two clips, a few bungees to keep the hoses tucked away)

This setup, would typically cost around 1000USD and up. The total course would set you back around 500USD.

With airline companies putting thumbscrews on weight and size limitations, this is a excellent solution, since the whole package doesn’t weigh much more than a standard scuba setup.

Once you have your tickets and gear in hand, you can go on any dive boat and use their standard tanks, so there should not be any extra charge.

Upon completion of the course, the diver receives a template / disclaimer that can be handed over to the boat operator should there be issues with you diving alone.

 There may be many other reasons for an experienced diver to wish to dive alone and to take the Solo or Self-Reliant diver course but in the end it comes down to the need to:

• Develop the skills of planning and carrying out dives without a partner when preferred or necessary.

• Sharpen your diving skills, making you a stronger partner in a dive pair or team.

This course will help you to recognise when diving alone may be applicable, and the need to compensate for those situations, including dive planning, life support system readiness, adaptive training, equipment and responsibility. You will develop the skills, knowledge and techniques necessary to rely on yourself.

 To begin this course you should be 18 years old, hold an Advanced Open Water diver certification, have 100 logged dives.

This course takes place over 2-3 days, consisting of theory sessions, equipment workshop and 4-5 dives.

Upon successful completion of this course you may engage in solo diving activities without direct supervision, provided that depths and diving conditions approximate those of training, with the use of multiple cylinders.

Blue Label Diving is a first to offer this unique combination and the courses can be run under either the PADI or the TDI umbrella

Get Smart

Master all the important academic information. Traditionally, this required several hours of formal classroom training. Now, through on-line training, you can complete this phase through self-study, at your own pace, in the convenience of your home or office.

Go Diving

The final step is to complete the required number of open-water training dives under the supervision of your SDI Instructor. Here you will apply what you have learned during your academic and skill-development sessions, while learning practical lessons that can only be gained through real-world experience in open water.

Get Wet

For entry-level certification courses (as well as some continuing-education classes), the next step will be to complete your in-water skill-development training. This takes place in a swimming pool or similar body of confined water, under the supervision of an SDI Instructor.

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Over the past several weeks, seasonal rains that are heavier than usual have resulted in widespread flooding in Thailand. While the flooding is having some impact, most key tourist destinations and attractions throughout Thailand have not been affected by the floods and almost all remain open. The flooding areas are Bangkok and some surrounding provinces.

Tourist destinations in southern and eastern Thailand remain fully accessible.

Major tourist destinations such as Phuket, Kha Lak, Chiang Mai, Chiang Rai, Sukhothai, Kanchanaburi, Ratchaburi, Pattaya, Ko Chang,  Ko Phi Phi, Krabi and Ko Samui, Ko Tao, and all provinces in southern Thailand, are not affected by the floods. They remain fully accessible and are experiencing normal weather conditions for this time of year.

Blue Label Diving Team