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Aug 27, 2015

A Diary of Rebreather Training

"Death Machine" is how most scuba divers perceive the closed circuit rebreather.

The technology has been around since the early 1600s when adventurous types were burning potassium-nitrate inside early versions of steerable submarines. Centuries before Jacque Cousteau began pushing the limits of the SCUBA unit, innovators were learning how to 're-breath' their exhaled gas without passing out from excess carbon dioxide.
The JJ rebreather

The vast majority of us don't know much about the gas exchange taking place in our own bodies. It's new knowledge to most that we are sucking in only about 21% oxygen and expelling most of it again without using it:

Gas% in inhaled air% in exhaled air
Carbon dioxide0.044

To those of us who do some breathing underwater, the problem of wasting large amounts of oxygen with every breath is worth throwing significant amounts of time and money at. Knowing that there is a product that we can buy that solves this problem is extremely exciting for those of us who are prepared to trust ourselves, undertake the training and spend the money and the many hours practicing.

For years, I looked sideways at the breed of divers who appeared to us to be courting death by using these strange 'closed circuit rebreather' (CCR) machines with 'hundreds' of wires and hoses.

Like most scuba divers I had stored in the back of my small brain, random scraps of rumors about the accident 'statistics' that showed the rebreather world in a bad light. Statistics, of course, can tell almost any story you require them to and people's personalities are not part of the numbers.

Now that I'm on the other end of an education about rebreathers, I have become aware of the extent of the lack of knowledge among recreational open circuit divers, including my former self.

Still, rebreathers are not for everyone.
After interrogating a couple of trusted CCR instructors, I asked myself the following questions:

"How badly does my pride affect my decisions?"
  • Am I too proud to use a check-list?
  • If my equipment fails even the smallest pre-dive test, am I too proud to abort?
  • Am I too proud to admit that I am not equipped to rescue myself or another?
It can be hard to be honest with yourself when answering these questions. It might be more revealing to ask more particular questions such as: "Have I ever chosen to just sit a dive out on the boat when my friends and colleagues have gone diving?" or "How complacent have I become about my automobile driving? Do I text when I drive?" or "Have I ever run out of petrol, been too cheap to replace bald tires or have I ever accidentally left my wallet at home, and why?"

Questions, complacency or absent mindedness become serious in the context of rebreather diving. If you're the scuba guy who jumps in with your single tank turned off, then rebreathers are not a good idea for you at the moment. For you a rebreather IS a death machine.

Leaving your wallet at home is inconvenient, but a similar slip of the mind when diving a CCR might kill you.
Megaladon Rebreather

My first practical interaction with a rebreather diver was in Israel. A dive guide wanted to get his CCR back in the water while showing me Eilat's "Silk Road"(video) and in the process of his preparation, I was given an introductory look at how an ex-military guy does an equipment build and check. It was a demonstration of focus, simplicity and bloody-mindedness (things dear to my heart).

A few years of open circuit diving later, I found myself filming on the wreck of the Coimbra, at 180 feet breathing plain old air.  My bubbles were scaring the fish, I was narced from the excessive amount nitrogen present in the breathing gas at six atmospheres and the plan involved about 60 minutes of drifting-boat-decompression on a heaving anchor line in unfavorable ocean conditions, after a very limited time underwater. The 'talent' was on a rebreather and I should have been on closed circuit too for a gig like that.

The time had come to start learning more about rebreathers, how they work, which kind would suit  filming/diving/traveling. As luck would have it, I was called to Belgium for work, and Brugge is the home of the rEvo Rebreather factory who make a machine that some divers prefer.

Pete with Paul, the inventor of the rEvo CCR

After walking through the tiny, quiet and almost deserted factory, the order was placed with some trepidation and I started doing homework for the training that was looming a couple of Months away.

Training was thorough, and as warned, my two colleagues and I felt like we were starting diving almost from scratch:

The books often tell you that 'your learning is only just beginning', even as you finish your course.
True, that is. So off to practice what you have learnt and strive to increase the strength of the muscle memory that will keep you safe when things don't go as planned:

It was emphasized to me that I should accumulate 30 hours on the rebreather, early on, forming good habits, learning quickly from mistakes and getting comfortable in less challenging environments, such as tropical water with good visibility. Bonaire was my choice of location and it would turn out to be a great opportunity to get used to shooting video while on the CCR and iron out a few kinks in my rigging of which there were many. Messing around with weight placement and different brands of fins was also necessary with the rEvo which tends to pull a diver's feet downward.

A little warm water wreck diving on an old favorite sunken ship "The Hilma Hooker" before heading back to the cold North East Atlantic waters where the conditions would be far more challenging.

Thanks for visiting. I hope this breaks the ice for those of you who are CCR curious.

Dive safe.

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