A brief history of leisure-diving rebreathers
THESE WERE SEMI-CLOSED-CIRCUIT units using ready-mixed nitrox. The only tanks we could find were standard aluminium 80s, which gave us rather a lot more gas than we needed for a typical dive.
John Beaumont came with us as Peter’s second-in-command. The gaffer tape that appeared to hold the units together didn’t fail and nothing untoward happened to us, though we did some things that make my hair curl to think about now. I wrote a feature entitled I Have Seen The Future And It Works!
Alas, Peter’s demo days with the then-hierarchy of the British Sub-Aqua Club went less well. They were unimpressed, probably because they had not got to grips with the very different closed- (or semi-closed) circuit diving technique.
In the meantime, Christian Schultz of Dräger in Germany realised that the company made a fire-fighting rebreather in Hythe near Newcastle that might readily be turned into a viable diving product.
He and Jurgen Tillman worked on the project, and the Atlantis SCR was born.
They employed Rob Palmer to gather all the prominent technical divers of the day in the Bahamas for a product launch. It was strictly a leisure-diving rebreather, and these guys were unimpressed. They felt it gave them nothing that twin-80s on their backs couldn’t.
However, we did Rob’s TDI rebreather course, which was probably the first to be written for rebreather diving. Christian admitted that the Atlantis was not a fully closed-circuit rebreather, but with all the rebreather hype that was going on at the time, he often reminded people that at least it was actually in production, unlike the “vapourware” offered elsewhere.
By now we were well into the 1990s. Martin Parker, the young managing director of the company that made Buddy BCs, was approached by both Peter Readey and a young Dave Thompson.
Dave was affectionately known by his friends as “Mr B&Q”. He had made a closed-circuit rebreather from plumbing parts and, with Martin’s factory’s help, they turned a couple of examples into electronic CCRs. Martin was quite taken by Dave’s prototype, and wanted to make one.
I was ignorant enough, stupid enough or foolhardy enough (take your pick) to go diving with them in the English Channel, to determine what “fully closed-circuit” really meant.
Apart from the obvious hazards of electronics that were not permanently watertight, we were all enthused. This really was the future!
GETTING THIS PROJECT into production took several years, however. Snag after snag became apparent, and Martin started calling the unit the “Perspiration” rather than what it was to become – the Inspiration. But he wasn’t daunted.
It became the first commercially available leisure-diving rebreather. The problem was that a lot of experienced divers who bought the magic yellow boxes failed to appreciate enough of the differences, nay the hazards, that came when changing from open- to closed-circuit equipment and techniques, and there were some high-profile casualties.
I was probably the first closed-circuit leisure diver. I enjoyed the long durations and short deco requirements available to me in relatively shallow depths. I used the Inspiration as an automatically mixing nitrox rebreather, never straying beyond
50m deep but getting some spectacular shots of skittish wildlife that had not been easily approachable before.
A typical no-stop time at 20m was around three hours, and I had the gas to do it.
However, most divers who bought an Inspiration saw it as a way to go deeper for longer without being encumbered by masses of tanks and, because a CCR is light on gas usage, they saw the great advantage when it came to using expensive helium mixes.
The Inspiration became the technical diver’s choice over conventional open-circuit gear. Developments such as auto-diluent addition (as the diver goes deeper) were added later.
Soon other manufacturers were chasing that particular breed of customer who was obviously prepared to spend a lot of money on diving equipment. VR Technology, InnerSpace Systems, Kiss, rEvo, JJ and many others joined the fray with their own unique selling propositions.
Even Peter Readey’s Prism is now back in a very developed fully closed-circuit form, manufactured by Hollis Industries and called the Prism 2.
Meanwhile, the new company spawned from AP Valves, Ambient Pressure Diving, had not sat on its early laurels.
Its original Inspiration was upgraded with better electronics, oxygen management and the built-in decompression software of the Vision versions.
There was also a head-up display and a temperature stick that gave some indication of what that all-important scrubber-pack was doing. The company even produced a smaller, lighter version for those divers who wanted it, called the Evolution.
Competition drives an industry forward, and soon nearly all competing products had built-in open-circuit bail-out valves and integrated decompression computers.
THE BIG FLY IN THE OINTMENT for me was that the insurers of the training agencies got windy following the early rebreather casualties, and insisted that all divers carried open-circuit equipment as an alternative if the diver encountered any problems.
This meant that the idea of swapping multiple tanks for a CCR alone as an alternative was no longer possible. CCR divers had to take both during training, and most continued to do so afterwards.
Going back to the beginning, American diver Bill Stone had previously been attempting to get the life-support system contract from NASA for man’s first space walk on Mars. He had built a very complex rebreather called the CIS-Lunar, with extra redundant systems, and was test-bedding it in the caves of Florida. Later, he turned his mind to what a leisure diver might want from a rebreather.
More recently, Poseidon in Sweden put Stone’s ideas into production, and the result was the Discovery Mk6, so called in deference to the fact that his last CIS-Lunar was a Mk5.
Whereas the other rebreather manufacturers had been seduced into giving technical divers what they wanted, Poseidon’s route was to make a depth-limited unit exclusively for nitrox-mixing, using air as a diluent, to take all that decision-making away from the user.
It had built-in technological solutions for dealing with any problems. It was simple to use. It self-diagnosed any problems before you went diving.
All the user had to do was to switch a lever on the mouthpiece (to built-in OC) if he or she saw a red light appear on the head-up display and felt the mouthpiece vibrate, and abort the dive.
Enter the people from PADI, the popular training agency. They decided to offer technical CCR training as part of a comprehensive raft of training products, but also believed that there might be a whole new population of rebreather divers who, like me, wanted to use a rebreather in a different way, for close encounters with larger marine-life.
PADI divided its new CCR diving courses into Rec and Tec levels, and further divided the Rec level into two groups – those limited to 18m and using the on-board bail-out possibilities of the unit, and those prepared to take an extra sling tank for bail-out and go as deep as 40m.
The first level addressed those who might want to try rebreather diving, for example, while on holiday.
TYPICALLY, PADI FOLLOWED its route of “further education” with its course, so that this holiday diver might progress to full technical trimix diving eventually. The Poseidon Discovery Mk6 looked to be the ideal unit for PADI recreational CCR divers.
VR Technology soon addressed this market too, and has launched the semi-closed circuit Explorer SCR in association with Oceanic and Hollis Industries, the companies that actually manufacture it.
Martin Parker, ever ready to meet a challenge, realised that his APD Evolution series was just as small as the rival Poseidon, and it took only a couple of design amendments and software changes to make it meet the criteria set out by PADI when it designed its Rec CCR courses.
Not only that but these units, as well as the Inspiration Rec version, could easily be upgraded to full technical diving specification should an owner so desire it at a later date.
The APD Rec2Tec rebreathers were born!