Cave diving can be broadly split into two very different categories.
Firstly sump diving which mostly involves carrying diving equipment through a dry cave environment to the sump. This is where the water table is found, and then in order to progress into a further dry cave, diving equipment is needed. Very often a side mounted cylinder configuration is used, which is unfamiliar to most divers. As we are open water divers first and foremost, this environment and gear configuration is not suited to us as we have no dry caving experience. If you are already a caver, and wish to progress into sump diving, then contact the British Cave Diving Group, who will be only too pleased to try and put you off!!
What is of interest to us is the second category of cave diving - spring diving. Springs are mainly found in North Florida, Mexico and central Europe. Obviously there are plenty of other diving destinations, but these three seem to be the most popular. The difference between a sump dive and a spring is that we do not have to drag our gear through a dry passage to start the dive. Springs are found on the surface, and can usually be entered with little or no effort. The diving equipment we use is almost identical to open water diving equipment, so the transition is relatively straightforward once we understand the environment. So what's down there? By far the most fascinating aspect of spring diving is just being in the cave environment. For us, the motivation is to see 'what's around the next corner' - Tom Mount describes it as the closest thing to being in space. I for one can see where he's coming from!
There is a labyrinth of fascinating passages to explore for the trained cave diver. In different parts of the world, you will come across a diversity of caves. You will dive through caves that were once dry which, as the water level has risen with time, have become flooded. Classic examples of these types of cave are found in Mexico. Called 'cenotes', they tend to be quite shallow and very extensive. They are also beautifully decorated with stalactites, stalagmites, and other drip stone formations. The other type of caves most frequently dived are found in limestone areas such as North Florida, the Bahamas and South West France. These caves are typically formed by erosion and whilst not as decorated as other caves, offer exciting diving through maze like passages.
Another
major influence for diving in fresh water springs is visibility. Very often the
clarity of the water surpasses the diver's available torchlight, making for
scenes not unlike those seen in science fiction films. It can be a mind blowing
experience to be the last man in a group of divers, and be able to see the other
torch beams in front of you, panning the walls of a huge limestone cave. You
really have to see it to believe it !! How do we do that then? Cave diver
training has been available in the States for the last dozen or so years, so
it's nothing new over there. It's regarded by divers to be just as acceptable as
diving in the sea. You just have to go about it in the right way. That, as
always, is where the crux of the matter lies...the correct equipment, training
and attitude towards the sport.If you are ever fortunate to travel to North Florida, you will see quite a difference in the gear that cave divers use and in the way it's configured. For a start, a manifolded set of twin 15's or 17's is regarded as 'de riguer'. Most of the Floridian cave systems are 30m or so deep, and therefore require a good quantity of gas to give sufficient dive duration. Whilst on the subject of gas, nitrox is almost universal in its use by Cave divers in North Florida. The amount of decompression avoided by using nitrox as opposed to compressed air is quite significant. The regulator first stages and hoses are configured to be streamlined and allow the cylinder valves to be accessible. Most divers use a steel backplate and harness configuration to mount the manifolded cylinders on. In between the plate and the cylinders lies the wing for buoyancy control. With this set up, all the components are bolted together in order to prevent anything falling off during the dive. Quite a sensible set up!
The other major benefit of this simple set up is that all the equipment is easily accessible and user friendly. It also has the major advantage of being probably the cheapest set up on the market, mainly due to the lack of frills and not having excessive amounts of useless d-rings and marketing slogans! The primary light is usually a canister design, capable of long duration with a powerful bulb. The primary is mainly attached to the waist belt of the harness, but occasionally they are mounted under the cylinders. The latter method is becoming less popular due to lamp damage and line entanglement problems.
One of the major causes of Cave Diving accidents is failing to carry three or more light sources, so we always take two back up hand held lamps in case the primary fails. These are also stowed on the harness, where they can be easily accessed. This set up is fast becoming popular with UK divers. You only have to take a look at divers' gear on boats these days to see the influence arriving over here. In fact the rig can be used for sea diving with very little or no modifications at all. In short, having the right gear and then configuring it correctly goes a long way to becoming comfortable and proficient in the cave environment. Now we need to be able to use it properly.
Cave
diving puts additional demands on our diving skills. When diving through a cave,
we are truly in three dimensions and therefore have added complications over
normal recreational diving. We now have to consider entry and exit points to the
cave, possible complications with route finding, the walls, roof and floor of
the cave can also pose potential hazards with silting if we don't swim carefully.
Another cause of diving fatalities is failing to maintain a continuous guideline
to the surface. During training, you will become proficient with reels and lines
and understand the protocols involved in making circuits and traverses in the
caves. Any diver who is comfortable and experienced with their equipment can
quite easily make the transition from open water diving to becoming a competent
cave diver. The best way to progress safely into cave diving is to go cave
diving, preferably with someone who is able to point you in the right direction
in regard to kit configuration and dive techniques. Obviously the ideal person
to take a cave training programme with is someone who regularly dives in caves.
This may seem an obvious point, but there are a lot of 'Super Instructors' who
appear to have more in the way of badges and certifications than your average
boy scout, but who don't actually do any 'real' cave diving. It's well within
your rights to grill your Instructor about their personal experience, before
parting with your hard earned dosh! Also make sure that the training programme
you are undertaking is going to be recognised worldwide. You will be very upset
if you turn up at Ginnie Springs with a C-card that they won't recognise and
therefore decline you entry. It is best to try and get 'dual certified' which
means that you will be able to dive in any spring environment in the world.If you are unsure, ask the governing body e.g. NACD, IANTD, NSS-CDS etc for clarification (see end of article for details).
But that's only the start. In order for you to become a competent cave diver you will need to do your fair share of the work too. Out of 27 of my cave students this year, 8 didn't make it through the training. Now don't worry, we don't expect you to go for a run in your twinset first thing every morning, nor do we expect you to be able to do 20 pull-ups at the drop of a hat, but you do need to have the right attitude towards the training and develop a healthy respect for the caves.
We are mainly sea divers, which means that buoyancy control and swim posture, really doesn't matter too much to us. Now we have to learn to swim properly and become more aware of our buoyancy and body posture. Why? Because there are plenty of caves with a thick layer of silt in them just waiting for a careless fin kick, or a pair of dragging fin tips. The key to maintaining the visibility in caves is to keep those feet up! At the same time we need to concentrate on maintaining a horizontal body position which will also help keep the vis intact. It is not surprising that most sea divers find this a difficult position to maintain along with checking line direction, looking out for the rest of the team and checking gas supplies - to name just a few of the tasks.
It can be uncomfortable at first, but once mastered makes diving in the caves far easier and safer. It also allows the diver to see in front and behind (between the legs) to keep an eye on dive partners and be aware of the line placement in the cave. The training is relatively in depth and after a week the diver will have spent a good few hours underwater in a variety of different caves. Of course it doesn't end there. Training is only perfected if you are prepared to work on the skills you have learned. Practise makes perfect, and once you have completed the cave course, go cave diving! There are plenty of places to do it.
A third major cause of cave fatalities is diving beyond the level of your training. Caves are very unforgiving and you only have to study accident reports for this point to sink home. No diver is immortal, and if you get lost, run out of gas or lose the line then you are in a very unforgiving environment. The grim reaper cares not what qualification card you have, if you make a mess of it, you're in his hands! Take your time and progress slowly. Dive with other cave divers who have had prior experience of the caves and develop a mature attitude towards cave diving. This way you will develop into a more rounded and proficient cave diver. Don't become a statistic - you're a long time dead!
To end on a cheery note though! - Cave diving can offer the well disciplined diver a new and exciting playing field. It doesn't require a huge cash investment, such as trimix diving does, and you don't have to be the world's most qualified diver either. If you are already diving with twinsets and hold an Advanced Nitrox qualification, you can go straight into the Full Cave diver programme. Once you have become trained you will meet other groups of divers, all willing to share their experiences and go diving with you, very often in some spectacular parts of the world.
The Full Cave diver course lasts 6 days, and at the moment is only available through IANTD and NACD in the UK. For information on Instructors contact IANTD on 01202 893315 or NACD on 001 345 32604.
IANTD - International Association of Nitrox and Technical Divers
NACD - National Association of Cave Divers
NSS - CDS - National Speological Society Cave Diving Section
CDG - British Cave Diving group.