Cave Diving

Cave diving is one of the most extreme and dangerous forms of diving. It is actually no longer considered scuba diving but belongs to a more advanced level of activity known as technical diving. A very high level of expertise and local knowledge is needed to lead a cave dive, although simpler sink holes and cave openings can be visited by a relatively novice scuba diver.

Caves offer an exciting, mysterious undersea world where you will find unique marine life, corals and other interesting features such as stalactites and stalagmites.

However, the vast, complex nature of pitch black underwater caves can be a death trap to a diver who is running out of oxygen. There have been many fatalities associated with cave diving but retrospective accident analysis revealed several common factors linking fatalities. As such an acronym was devised to warn cave divers of the precautions they must always take in order to avoid lethal accidents. T he Good Divers Are Living is an international standard and stands for the following:

• Training. A cave diver never exceeds that which he has been trained for. Cave diving is taught in modules that combine theory with controlled practice. Fatalities have occurred when cave divers versed in theory have attempted to apply their classroom skills in new uncontrolled situations. It is believed that insufficient experience means cave divers are less likely to able to recall and apply their theoretical knowledge in the face of rising panic.

Cave Diving

• Guide Line. Not using a guide line is the main reason for death among untrained divers entering underwater cave complexes. It is the cave dive leader's job to constantly feed out a tensed guide line that is affixed to a point outside the cave entrance. Should visibility be obscured by current lifting silt from the surface of the cave, divers should be able to find the taut line and follow it to safety.
• Depth Rules. The maximum depth of whichever gas mix is being used must be adhered to, regardless of the layout of the cave being dived. Nitrogen narcosis can have far greater consequences in caves then in open water, where it is already serious. It is worth noting that depth complications are the principal cause of fatalities among trained cave divers.
• Air Management. Cave divers adhere to the rule of thirds, allowing a third of their oxygen for entering the cave, a third for leaving and a third in case of emergencies. This final third is also meant to help out your dive buddy should he fall into difficulties. In the UK cave diving scenario the extremely narrow spaces that have to be navigated mean there is little a diver can do for a colleague in trouble. For this reason the UK cave diving protocol is to plan your dive as if you were diving solo, which is often the case. The rule of thirds was made for diving in US caves where there is a current that helps a diver to exit the cave more easily than he entered. In UK caves this is not the case and considerable more oxygen may need to be reserved for exit.
• Lights. Lights are extremely important in cave diving as there is no external light source. A cave diver carries with him three light sources - a primary cave light and two back-ups. In the event that any one of these dive lights fail, the dive must be cancelled and all divers return to the surface.

In the UK most underwater caves can only be accessed by navigating lengthy portions of dry caves first. For this reason, the majority of UK cave divers are already skilled cavers. Only a small percentage come directly from recreational scuba diving.

Cavern Diving

Cavern diving is the next best thing to cave diving. This is where you do not enter into the cave system (penetration) but merely explore the opening structures. Thus the recreational scuba diver can discover the mysteries of undersea caves without going through a full technical diving qualification. You may train for a specialised PADI Cavern Diver qualification. Unlike cave diving, however, your depth will be limited.