‘An underwater cave is an invitation into the unknown’ Jill Heinerth
One of the most mentally and technically challenging form of diving is cave diving. Cave diving is a type of penetration diving because the diver, in an emergency can not swim vertically to the surface due to the ceilings of the cave and instead must swim e whole way back out the cave tunnels.
Compared to recreational diving and cavers there are relatively few cave divers this is probably due to the specialised equipment and skills required for cave diving. And perhaps also because of the high potential of risks including decompression sickness and drowning.
Despite this, however, caves attract divers due to how unexplored they are and they give divers a technical challenge. Underwater can also contain fauna not found anywhere else in the world.
Cave diving is perceived as one of the most deadly sports in the world. However this is arguable because the vast majority of divers who have lost their lives in the caves have either inadequate equipment and/or have not undergone specialised training.
Today there are five general rules for cave diving:
1 Training A safe cave diver will not exceed his/her training boundaries intentionally. Only by steadily building experience can a diver remain calm to recall training procedures. In the event of an emergency when faced with the sme situation an inexperienced diver is more likely to panic than an experienced diver.
2 Guideline A continuous guideline is used at all times between the leaders of the group and the entrance of the cave. Failure to use a guideline is the most common cause of death among untrained diver who enter the caves.
3 Depth Rules Air consumption and decompression obligation increases with depth. It is critical no diver exceeds the dive plan or ‘Maximum Operating Depth’ of the gas mixtures used.
The effects of nitrogen narcosis are more apparent in the caves than in open water. Excessive depth is frequently said to be the cause of many trained diver’s deaths.
4 The Rule of Thirds The most common rule is the ‘Rule of Thirds’. This rule is a must when diving in the caves. Cave divers will always calculate their air consumption in thirds; one third to enter the cave, one third to come out and the last third is a reserve ion case of an emergency such as a freeflow or other type of gas loss. If this type of accident occurs and the diver has stuck to the rule of thirds you should be able to make it out of the caves alive.
If the conditions in the cave are more demanding such as with current cave divers will use the rule of sixth which means more conserved air for an emergency and swimming upstream.
5 LightsCave divers must take three independent sources of light with them; one is used as the primary source of light and the other two as back up. Each torch must have a burning time of at least the planned duration of the dive. If any one of the torches fail during the dive the dive is called off for the entire dive group. A cave diver must carry spare lights in case one leaks, breaks or gets lost.
Although there aren’t really any laws that regulate what divers can and can’t do during their dive in the cave people are generally told not to disturb the environment and to never remove fossils or artefacts from the cave.
Once you’re a cave diver you can pretty much diver anywhere in the world. You do not usually need a permit or permission to dive a cave. By sometimes there are restrictions from the location. Some places will require you to show certification before diving, others do not allow non-cave divers to carry a torch. Some places will charge an admission fee, and once you’ve entered you can dive as much as you want. But once you’re a certified cave diver it’s up to you to make the dive plans, decompression schedules and decide on the gas mixtures you’ll use and so on and so forth.
Warning; reading this post does not mean you are a certified cave diver, I am not a cave diving instructor and all the information above was from my own research and conversations with cave divers. Under no circumstances should you go cave diving after having read this post unless certified to do so.