Speleology is the common term referring to caves and their science of exploration. Hence the off-shoot term ‘spelunking’, which some of us may have Christian Bale use as a cover for his superhero identity to Morgan Freeman, when asked what on earth he gets up to with the all the black ‘suits’ in Batman Returns. Cave diving branches off Speleology’s many technical–natured divisions, employing specialized equipment to explore rather unique natural features. The sport also falls under the subdivisions of penetration diving, which also encompasses wreck and ice diving.
We have all been ‘in a tight spot’ and ‘between a rock and a hard place’ metaphorically, but being there physically, for the sake of recreation or scientific study presents a whole new ball game.
- Basic considerations for cave diving include:
- Restriction to direct ascent due to cave ceilings.
- Horizontal swimming as the prime navigational method.
- Tricky and distanced exit routes
- Fluctuating visibility conditions
- Strong and extremely dangerous environmental water currents
As many as 400 untrained divers died in Florida’s caves alone due to neglect of basic safety factors. Most modern literature on avoiding risks and educating the public and prospective cave divers on the realities of the risks and safety is based in the research of cave diving pioneer Sheck Exley, who discovered that all the deaths in the field could be traced back to a handful of the same contributive factors. His research dates back to the 60’s and 70’s and since, two additional crux factors have been added to his original three pointers.
The results of the research can be summed up under the five following factors, which now fall under an area of study known as Accident Analysis, presented during all introductory Cave Diving courses:
1. Monitor the guidelines to your exit as if you life depends on it – because it does.
There’s no worse feeling than instant claustrophobia that appears suddenly due to a panic of ‘not being able to get out’. Cave diving without a guideline is like deep diving without a cylinder. In a proper cave diving scenario guidelines are posted at one point outside the cave entrance. The line is monitored and kept properly taut at all times.
2. Breathing gas considerations:
A regulation in diving applied across the field is ‘the rule of thirds’. In other words: a third of gas is to be kept for ascent, a third for decent and a third in case a buddy requires it in emergency. One of the main problems faced in caving was a lack of oxygen to reach the exit.
3. Depth Rules
The gas mixture in this case dictates the MOD or maximum operating depth applied in accordance. Nitrogen narcosis risks are higher for cave divers - making the effort to not exceed cylinder pressure beyond a certain point differs vastly in this case to your average open water dive.
4. Ample light back-up sources:
Cave divers need to carry at least three battery powered light sources per diver. The basic rule is: no light - no diving. As we are all aware, state-of-the-art doesn’t necessarily mean fail-safe. If a diver has a light malfunction during the dive, it’s called off. It’s possible to remain calm in the dark but disorientation naturally leads to panic. Contact with the guideline may be lifesaving in this instance, yet on the flipside it could be time-consuming due to precautionary measures taken whilst moving slowly in the dark. This in turn reflects negatively on air consumption and the inability to monitor levels due to bad light.
5. The bottom line is simple: don’t dive caves if you haven’t been trained to:
Due to the varying skills techniques required for cave diving, it has been proven that even theory is not enough to overcome the risks. Experience and knowledge gained has to be practically applied in accordance with the different training levels, before ascending (or skipping) the next rung to course completion. The lesson is not to exceed the limits of the present level of acquired training.
- Over and above each of the above-mentioned pointers, training for cave diving covers:
- complex navigation
- propulsion (dealing with silt-rich environments)
- as close as possible to instructor-level buoyancy techniques and
- psychology among others.
Cavern diving differs from cave diving in that divers generally remain 130 feet from the surface and keep the entrance in sight at all times. It falls under a more recreational subdivision of cave diving, using similar equipment to open water dives. The basic idea is to get rid of anything and everything that dangles. Cave divers even drop the snorkel from the mask in order to avoid unnecessary drag and entanglement and stick the mask strap into their hoods.
As with open water dives, adjustable fins are used, however the diver’s preference remains with simple and practical. Split fins are a recipe for disaster and do not serve important cave diving techniques, as are straps and buckles. Spring heel straps are good for quick removal in case of emergency and do not lend to entanglement.
Anything less than a 5 millimeter thick protection suit is not recommended when diving deep and staying down for as long as 90minutes. BC configurations require the likes of wing style jackets, preferably with D-rings at the shoulder and waist, a valve at the shoulder for quick dumping and a stainless steel or aluminum back plate.