Monday, January 28, 2008

The VR3 vs the new X1 (aka Picking a Helium Computer)

Want a VR3 but can’t afford one ?
There are a number of items that seem to be permanent fixtures on any technical diver’s wish list… a dry suit (because 3 hrs in the water is a long, long time and hypothermia is still not a fun way to spend an afternoon), a rebreather (come on, you can admit to wanting one, even if you currently think all rebreather divers are elitist because they can stay down for longer and do less deco) and of course, a Helium computer.
Up until the arrival of the VR3 if you wanted to dive Helium you had to do it the old fashioned way - with tables you cut on land using something like GAP or V-planner. This meant that you had little flexibility in the water, especially if something went wrong. Now I guess I need to confess up front that I sometimes fall into the category of old fashioned and suspicious of ‘new;’ things when it comes to some aspects of diving. I had heard about VR3’s but did not really see why I should drop 17k on one. Especially as I would need two (in case one did some unplanned load shedding (South African joke… we are going through power cuts thanks to the lack of planning by our national electricity provider)). I did not need a fancy computer that did all that for me underwater. I already had a decompression program and as all deep diving needs up front planning, what was the point ? Dynamically diving helium just seemed like a recipe for disaster. I could see diver's willy nilly doing 2 hour dives just on their computers and running out of gas having not done any up front planning.
Then I went as surface marshall on Dave Shaw’s dive and was blown away by the sheer power and flexibility of the VR3. Every diver had one, and thanks to those elegant little devices, I was able to leverage every spare minute out of every spare diver I had. I needed to. When Dave did not return all the deep support divers overstayed waiting for him (thanks to their VR3’s (and their rebreathers, but once again, that is a different story)). When Don Shirley blew his electronics at 127 meters and did his emergency ascent, followed by a near lethal ICDS hit (long explanation short, an inner ear bend) the day really fell apart. Out of 8 support divers I had 6 that had been to 100 meters and deeper, leaving me with two divers who had not started their dives and now had to manage continuous support for at least 4 hours (which was how long it would take to get one of the other guys out of the water and some surface interval time). Oh, and they had to do the first three hours of this in the 30 meter to 50 meter zone. Suddenly the idea of a VR3 was not so silly. I bought one.
And boy has it changed the way I dive. The decision to dive helium as opposed to air has always been one I have left to deep dives (deeper than 65 meters). And because of the inconvenience of having to bend my normal computer, cost, planning etc the number of deep dives I used to do was minimal. These days (thanks also to a rebreather which makes the cost of helium affordable as I hardly use any on a dive) my VR3 means I get to dive more. I need another one in fact, if it was not for the price.
As a technical dive school Liquid Edge firmly believes in two things. 1) Removing limits (Score one for the VR3) and 2), Finding and providing dive gear at affordable prices. Which is where VR3 loses out. If you were to ask local shops for a price on a VR3 you should expect an answer of around 17k for a ‘fully loaded’ (rebreather, helium capable) VR3. If you balked at that (which I certainly did) and started to do some internet research you would find that divers warehouse in the UK ( will sell you the same item for £749 (excl UK VAT). Now, even at the pound exchange rate (R14,3 on a good day), shipping (add £70) and Vat on this side (14%) you are looking at R13,400. That is way more reasonable than 17k.
But we wanted to know if their was an alternative and guess what we found ? A brand new Helium computer that is looks like it out classes VR3 in all aspects, not the least of which is price. The Liquivision X1 (
Here is a quick product comparison:
- Downloadable (VR3 - Add £80)
- Depth Rating 350 m (VR3 - 150m)
- Tested to 450m
- Sealed unit (VR3 not)
- Uses either Gap or Vplanner (VR3 uses decoplanner)
- Tap Switches with x, y axis (VR3 is push buttons)
- Rechargeable Battery (40 hr life) (VR3, user replace'able)
- Upgradeable from internet (VR3 - not)
- Price R13k (VR3 R14.7k)
(Please note prices above are based on R7.40 to the $ and R14.3 to the £)
Finally, some choices! I have mine on order and will certainly tell you guys all about it when it gets here.

Wednesday, January 23, 2008

The Myth of the Deep Bounce (How Easy is Soap on the Rope ?)

As you may (or may not) know, I hold the woman’s world record for the deepest dive (221 meters, set at Boesmansgat in the Northern Cape). The one thing that I did not expect after achieving this were the mixed reactions I received from fellow divers.
There are definitely two camps, those that are fascinated and excited and those that do their utmost to minimise the achievement. From that camp has come the term ‘soap on a rope’ which is meant to indicate that there is nothing very special about doing a deep bounce and that anyone can do so. If you were a real deep diver and explorer you would be swimming off the line and spending time at depth, or so the argument goes.
Which started me thinking, “Is a deep bounce dive a cop out or is it something to be proud of ?”
The existing deep records require that a diver to descend (normally as fast as they dare) to their designated depth, spend a minute or less (to make sure depth gauges record the depth achieved) and then return. The actual exposure to depth is measured in minutes, if not seconds. And I guess the uninformed can be forgiven for taking the dive at face value and declaring that it is hardly difficult. Yet if one looks at the survival rate of the divers who have attempted this so-called ‘simple’ dive, a different story emerges.
Firstly the number of divers who have made it below 250 meters is limited. I count only 5 who can justify their claims (through a combination of gauges and tags retrieved). They are Nuno Gomes (the current world record holder for depth and deepest cave), John Bennett (the first man to break 300 meters), Sheck Exley (father of deep cave diving and original record holder), Jim Bowden and rebreather diver Dave Shaw. Of these every one had issues, ranging from serious inner ear bends, minor elbow bends and inner ear problems.
Every one of these divers was after one thing, finding out how to get deeper and back. None attempted to swim at depth. None at least until Dave Shaw. Dave was an Australian rebreather diver who I met on my world record dive expedition. He was planning to try for 300 meters (a new cave record) a couple of days after my dive. Instead he found the body of Deon Dryer. His plan saw him descend down the shotline to the bottom of Boesmans (about 260 meters) and then swim off to find depth. The dive required only a short swim at depth and while he was successful the first time, he never made it back to the main shotline on his second dive.
Admittedly these divers were pushing the edge of what is known, so how much safer are bounces in the 200 to 250 meter range ? One of South Africa’s more experienced instructors Don Shirley can attest to the effects of a simple and easy soap on the rope that went wrong. When supporting Dave Shaw he descended to 227 meters (according to his VR3’s) and barely made it back alive... and that was a dive not much deeper than my soap on the rope record.
None of which supports the argument that ‘anyone’ can bounce depth and survive now does it ? After all, these are some of the most experienced, accomplished divers in the world and their track record tells a completely different story.
So what is stopping deep explorers from spending time in the sub 250 meter zone ? And what makes bounce dives so deadly, even though their execution seems to be so relatively simple ?
The first problem is gas. As open circuit divers you only have so much gas to take with you which means that a couple of minutes is really all the time you have at depth (the deeper you are the more gas you use on a single breath and the more gas you need to get there, never mind build in safety in case something goes wrong).
The second problem is that tables are not designed for either depth or swimming. On a bounce you can keep your heart rate low and so minimize your absorption of helium and nitrogen. However, when you swim you change the absorption characteristics of your body… taking in more than the tables are expecting. We get around that by building in fat, an extra minute at depth that you have no intention of spending, plenty of deep stops of at least 2 minutes). But still, the resulting deco profile is an educated guess. The only way you know if it will work is by doing the dive.
Which leaves us with the one problem that has not been solved, accurate decompression profiles that predictably and repetitively eliminate bends. Right now a simple bounce is just impossible to predict and whilst spending time ‘exploring’ sub 200 meters is every diver’s ambition, it adds a whole new level of complexity to an already complex equation. Don’t get me wrong, I love complexity. I love problems that are deemed impossible. For me that just means that someone has not thought about it the right way… and maybe I can.
So are deep bounces minor dives that any diver can tackle ? No! Deep bounce dives are hard! To that the divers who have been there can attest! It does not matter if you spend seconds or minutes, the physical and mental challenges remain! Next time you hear a diver making light of these dives take a second. It is easy to belittle another’s achievements. Indeed, it seems to be a norm in society and not restricted to deep diving.
Aha, you are saying. ‘Of course she is going to say that, she is one of the people who get belittled!”
Let me tell you a secret. What I have gained from my world record is not recognition, fame or glory. Those may (and probably were) reasons that got me started, but they are not strong enough motivators to keep you going when everything goes wrong. It is not enough to be able to dive, you have to find support divers and money and equipment. You have to learn how to dive deep, safely and there are no courses out there to teach you and even fewer experienced mentors willing to take you under their wing.
I may have started out wanting a world record to prove something to the world but what I found out was that I was actually proving something to myself. The journey to a world record is highly personal and very, very internal. The value I attach to my record has nothing to do with your opinion of it (or me as a result). Thanks to this one relentless desire of mine I found out who I could be.
I also learnt that limits are choices and that the only limits that exist for me are the one’s I believe in. There will always be people trapped in a world defined by limits and they will always be the people who belittle other’s accomplishments, and there will always be people who want something enough to go ahead and do it, in spite of what the world around them thinks. It does not really matter if the limit you are pushing is the world’s or your own. Is the personal challenge any easier for people who climb Mt Everest today ? Even with modern technology and sherpa’s many do not make it.
I think Nelson Mandela put it best, ‘And as we let our own light shine, we unconsciously give other people permission to do the same.” So next time you hear a story that makes less of an achievement, take a minute… and put what you are hearing into perspective.

Monday, January 21, 2008

Advanced Nitrox - Necessity or Luxury ?

As a normal sport diver your limits are 40 meters, no decompression diving (NDL), which gets you to most places and on most dives. The only thing is, at that depth you are at the limits of air and even on nitrox, can not spend much more than 8 minutes exploring. Now I don’t know about you, but no reef is worth the price and effort for 8 minutes, make that 25 minutes and we are starting to talk business. Which is exactly what you could be doing if you were able to do decompression.
These days most divers have a Nitrox certificate, so most of you already know what a difference nitrox and reduced END’s (equivalent narcotic depths) make to the quality of a dive - not only do you get to stay for longer before hitting NDL limits, but you physically feel better after the dive. Advanced Nitrox is a logical next step. For some it smacks too much of technical diving, which is in turn associated with danger, risk, complication and money. However, investing in an Advanced Nitrox course is not as pricy as you may think. Nor is it a choice you should only be making if you are thinking about becoming a deep or cave diver.
This a course that improves your skills and safety underwater without unnecessarily increasing your risk or requiring a hefty bank loan and spans of heavy, complicated gear. Interstingly, this course is not considered technical by the agency’s, and is classified as a ‘sport’ course.
Lets take a look at the gear requirements. You can use your existing sport set up (single cylinder and jacket bc) with one addition, an H-valve that allows you to attach two dv’s to your cylinder. You will also learn how to manage one extra cylinder for decompression. Easy, simple and very, very do’able. Or you can be more adventurous and replace your jacket bc with a wing and backplate (you can still use single cylinders). A lot of people in fact prefer this configuration as the backplate and harness system is clean, with no added bulk in front of you and lots of space to clip things. The cost ? Around R2,7 k for a Frog wing and backplate.
The course itself normally takes 4 days. At the end of it, you will know how to safely do decompression dives and manage your gas ensuring that you have more than enough to do your bottom time and your decompression and manage if something goes wrong with your buddy. I should mention at this point that as a CMAS diver, I started off on my open water one course learning decompression so for me it is completely odd for divers to have to get out of the water in order to avoid decompression. With the arrival of deco computers divers often make the mistake of thinking that they do not need a course to teach them how to do deco dives, their computers will do it all for them. But, did you know that divers still bend on computers ? And what happens when your battery goes flat, mid dive ? Do you understand how important the stops are and how much flexibility you have in maintaining your depth for those ? Do not get me wrong, decompression diving is not excessively dangerous, not at sport depths. Especially if you have had training.
There is one other important aspect of the training that is perhaps even more important than removing the no decompression limit. This course ensures that you recognize and face the real risks of diving and then ensures that by the time you are finished you have practiced managing those so many times that you can easily and quickly get yourself to safety.
This shift from a buddy to self rescue is fundamental and as far as I am concerned the biggest benefit. It worries me how easily divers place their lives in the hands of instructors and or buddies, with no proof that either are capable of managing a catastrophe underwater. And the thing about situations underwater is that you have very little time to get it sorted. How you react is critical! The calmer you are, the more practiced you are in the skills, the better your chances of making it back to the surface. Personally, I do not allow myself the luxury of having someone to blame when something goes wrong underwater (and if you dive long enough, it is always when, not if something goes wrong). It is my life and I take full responsibility for it. Besides, it is a false sense of security to have some one to blame and hardly does you (or your family) any good when you are dead, because your buddy did not come to the rescue.
Personally, I hate limits! Especially artificial ones (which the NDL certainly are). Besides, there are all those reefs out there with no other divers on them, just waiting to be explored. That is how the Coelocanth was discovered…by a diver just exploring where others did not go.

Tuesday, January 15, 2008

Why Sport Divers should go Technical

One of the frustrating things about being labelled a technical diver is the image of technical diving as being only for hardcore, extreme exploration. Yet technical diving is something that every sport diver should consider simply so that they can improve their own safety underwater.
Sport divers seem to have the perception that so long as they stay below 40 meters and within no decompression limits, they are safe. Yet when one looks at statistics (such as those published by BSAC it becomes clear that it is the sport divers and not the technical divers that carry the highest risk. A look at the statistics shows firstly that the majority of the incidents taking place do so below 30 meters. Secondly, the statistics seem to indicate that a lack of basic skill (specifically ascent rate) are to blame.
These trends tend to enforce my personal experience of sport divers (garnered over 15 years, ten of those as instructor). Once sport divers acquire their open water 2/ advanced certification, they tend to think they are invincible and can do any dive… so long as they stay within the no decompression limits. The introduction of dive computers has not assisted, with divers simply strapping on a computer, grabbing a cylinder of air and going where they please.
This attitude was highlighted recently when I heard about an experienced PADI instructor (with no technical qualifications, so limited to 40 meters and using a single tank and air) who was proudly advertising a weekend excursion to Wondergat (one of South Africa’s inland dive sites with a fascinating cavern that starts at 40 meters and extends back about 100 meters to reach a total depth of about 60 meters) where she took not one, but three students to the back of the cave (60 meters and requiring a 100 meter swim with a descent of 30 meters), on air. Because of its depth this dive is a normoxic, Intro cave dive and most definitely not a deep air, advanced diver dive.
Now as a deep air diver myself I can hardly point fingers, except for one thing, my deepest ever deep dive on air was to 65 meters and I never, ever go deeper than 50 meters without weekends of build up. I also never, ever go deep on air without twin sets and staged bail out. Their dive was on single cylinders. They had placed a single bail out cylinder somewhere on the way up. Much good it would have done them if they had needed it. The swim out of the back of the cave is hard, especially if you are panicked, have lost a light and destroyed the visibility. The instructor thought she knew what she was doing because she was an instructor. They all came back, which just enforces their perception that they are brilliant divers and that this is an easy dive, well within their capabilities. But they were lucky. That exact same dive, under exactly the same circumstances (except that the instructor was actually technical trained and experienced) killed himself and his student. The student panicked and ran out of air at the back (they were on singles, it was dark… and deep). The instructor assisted, but they never made the staged bail out and ran out of air on the swim out..
Sport diving is only safe if you do not break the certification limits. If you want to go deeper or stay longer you must have a course such as Advanced Nitrox. If you want to become more self reliant and to reduce your risks on sport divers than you should definitely do an Advanced Nitrox course.
In my next post I will go into the basic skills that you need to safely explore the so called ‘sport’ (40 meters) zone underwater.

Welcome to the Liquid Edge and the World of Technical Diving

As a diver there is a line that defines you - an edge if you will between where you are and where you are going. This is the liquid edge and is as much about learning new skills, as it is about pushing past your own definition of what you think you can and can not do.
As a diver you probably define your growth by the courses you have taken and the skills you have acquired. Until one day the next course is no longer defined as sport diving, but as technical. Technical courses are not only designed to get you deeper for longer. They are as focused on improving your safety underwater by increasing your understanding of the risks and giving you a tool set that allows you to minimise these. In fact, technical courses should give you a new confidence and attitude toward diving. You may or may not be interested in exploring deeper than 40 meters or in overhead environments like caves and wrecks, but that does not exclude you from integrating technical skills and thinking into your ‘sport’ diving. Technical Diving is about exploring, be it the sea or inland caves. It is about learning new skills. Becoming a technical diver is all of that and more.... because becoming a technical diver is also about exploring your own limits. Limits are choices and the only limits that exist are the one's you believe in!

So welcome to the world of technical diving where choices are limits. Have you chosen yours ?