Cave diving

The cave diving is a special variant of diving, which is associated with elevated risks. However, for scientists, it is often a necessary condition for caving ( speleology ) in caves and caverns that lie beneath the sea or karst water level. Even in water-filled underground mines, the techniques of cave diving are applied.

While the cavern diving can be performed relatively safely even by less experienced recreational divers needed for deeper dives, away from sunlight and an output, multiple redundancy in the over vital parts of the equipment and the risks customized diving skills. This one can acquire in cave diving training. The diving on of caves is approved, since it is not rare, with a great danger for the divers and the cave that could be damaged.

Cave zones

The cave diving is divided into three different zones of CMAS:

Zone 1 - Cavern

The cave diving ( often known colloquially as cave diving and English: cavern diving ), so dive in Zone 1 means that is immersed in the entrance area of the water-filled, natural or artificial caves or grottos and indeed within the illuminated with natural light range.

Zone 2 - Cave

Cave diving (English: cave diving ) means that is immersed in water-filled, natural or man-made caves and indeed beyond the area with natural light ( total darkness ). The divers do encounter deep until bottlenecks, siphons and up to 30 m into the cave before. This zone is referred to in English as apprentice cave diving.

Zone 3 - Full Cave

In the extended cave diving ( english: full cave diving ) be dived and explored larger cave systems. The divers come up to several kilometers deep and partly before on days-long expeditions in a cave.

Training

Various diving organizations offer training for cave divers. Partially orient them to the set of CMAS three cave areas. Some organizations offer a cave diving training for recreational divers, which is - contrary to the name - is mostly a marketing authorization for the cave diving ( Zone 1). Since cave diving is associated with significant risks, is strongly discouraged by a self-paced approach.

The following courses are offered by the world's leading diving associations:

Training of CMAS

The CMAS training system according to which also form affiliated organizations, defines its three levels of training as follows:

Cave divers I

The diver diving on the learned of caves in the light area (daylight) of the input. Depending on the organization as the maximum penetration distance 50-60 m defined and a maximum depth of 18-20 m. This type of cave diving is popular with normal recreational divers. There are other limiting constraints such as minimum size of the Ganges, minimum visibility, branches ( Prohibition of jumps ), minimum device size and air as the sole gas, pure no-stop dives, just to name a few.

The caves of zone 1 ( Cavern ) be characterized or delimited ( CMAS ):

• Direct view ( and access ) to the free water surface, always plenty of natural light
• No constrictions / constrictions (2 divers can happen together with full equipment )
• Visibility at least 10 m
• Max. Depth of 20 m
• Max. Distance to the water surface 50 m
• Permanently installed, continuous guide line
• No siphons, no grottos / caves with cave downward ( inward ) directed flow ( no shrinkage) and no caves with alternating flow direction ( no Estavellen )
• No branches ( jumps ), the main line must never be left
• No traverses (start with an input, get off at another )
• No gaps ( Interruption in the leash necessarily mean reversal)
• Circuits / Loops only if all of the above within limits and if the " Cavern Line ", respectively. is the " Cavern Circuit" permanently installed, completely enclosed and marked.

Also in terms of equipment redundancy and the gas management there are corresponding rules. Nevertheless, a "normal" recreational divers can be " made ​​fit ", there to perform safe dives under the supervision and guidance of an experienced cave guides or instructors with little adaptation of its free water equipment and with a relatively short theoretical training for the Cavern area.

The Diving Association CMAS required as a condition:

• At least 16 years old,
• CMAS two star diving license ( equivalent to a Rescue Diver PADI )
• So far at least 25 logged dives,
• Minimum 5 night dives logged
• Valid diving medical certificate (less than 1 year).

Besides recommends Diving Association CMAS:

• Special Course orientation,
• Special course navigation,
• A high level of physical fitness,
• A high level of mental stability and
• A non-aggressive attitude.

Cave Diver II

Here the daylight range is exited. Decompression dives are not unusual, as those with Nitrox (depending on the training organization ). Zone 2 is further defined (for T. organization dependent) with respect to a certain minimum sight distance, the prohibition by diving from constrictions with a minimum size, a maximum depth of usually 30 m, the lack of use for stage bottles, no post -siphon dives and other limits.

Some organizations divide this stage into two stages: ' " Intro to Cave and Cave Diver.

From dived environment, further demands on the equipment and training, which are naturally much more stringent than for the Cavern area arise. This is definitely a cave area where a scuba diver without proper equipment and training shall be dived nothing.

The CMAS required as a condition completed at least two-star or PADI Rescue Diver training, as well as a Cavern Diver certification, and experience evidence, so that the cave diving technical basic understanding already exists.

Cave Diver III

This is the highest and most demanding level of cave diving for the zone 3 Among all that is not covered by the preceding two stages falls, in particular: any penetration distance, narrow, post-sump diving, depths up to 40 m EAD, any visibility down to 0 m, other respiratory gases than air, use of stage tanks, long-range dives, decompression dives, bottlenecks down to the size of so-called squeezes, etc.

The CMAS requires at least a three -star or PADI Divemaster diving license and a Cave Diver certification.

Problems and risks

Cave diving is more dangerous than regular sports or professional diving; Statistics call a 130 -fold increased risk of accidents and fatal accidents show a relationship with the age of the divers and the level of training.

Pressure compensation

Natural caves rarely result in precise horizontal, what different depths means and thus also have different pressure conditions ( at the surface of ~ 1 bar, at 10 m depth ~ 2 bar, 20 m ~ 3 bar, etc.), which must be compensated by the diver, if he wants to suffer no barotrauma.

Loss of orientation

The flippers of a diver can stir up sediment on the cave floor ( silt out). It also happens that the bubbles of exhaled particles from the cave ceiling solve ( percolation ), which sink to the bottom. These suspended particles can lead to very restricted visibility. To find your way to the exit in poor visibility, a continuous guide of baited hooks, which unwinds the leading divers in penetrating from a roll (reel, spool) and attached meaningful. The diver can orient haptic At this leash. In some caves there are fixed leader lines.

Constrictions

When foray through a gap not only sediment is stirred up, but the equipment is subjected to a high load. Since the cave divers in contrast to cavers out of the water necessarily carries a heavy bulky equipment that he can not completely discard easily, there is a greater risk of getting caught or wedged in narrow passages. Why cave divers dive unknown bottlenecks often with the feet first, while head is preceded geschluft when driving on dry rule.

Breathing gas supply

Cave divers dive usually after ⅓ rule, ie one third of the entrained breathing gas into the path into the cave and a third used to exit the cave. The last third is a safety reserve. In an emergency, the reserve must be enough for the dive buddy. Often breathing gas depots are created under water in order to have sufficient breathing gas for decompression stops available near the entry area. If you have to dive and decompressed with a siphon, so the breathing gas required for this purpose must be carried all the way. The above-mentioned so-called " rule of thirds " will be adapted to the circumstances and experience of the divers if necessary, in terms of greater security.

Mental stability

Due to the frequent lack of ability to perform an emergency ascent, limited visibility, darkness, claustrophobic space and partially cool water, cave diving is a high mental stability and prudence of great importance in order to avoid unforeseen events that panic arises and the diver or his Buddy brings in mortal danger.

Risk of injury

The diving in a cave with protruding rocks, stalactites and other obstacles harbors particularly serious threats to external injuries. Abrasions are prevented by the diving suit; this is partly also protected in narrow caves by a worn over Schlaz. A helmet to which also serves as an attachment point for lamps, the head is protected. Especially dangerous is the toast of air-filled passages between the end of a siphon. Here occur from falls most serious accidents.

Gas inclusions

In water-filled caves sometimes gas-filled bells are to be found. Divers should always resist the temptation to breathe the gas mixture in these bells, because the risk that a sufficient amount of oxygen or toxic gases are included.

Flow

Usually dipped against the current into ( upstream) and dipped back with the flow (downstream). Caution is advised when caves and sections will be dived into it with flowing water ( Ponor ) because the way back is against the current. As a result, the time required, the physical effort and breathing gas consumption is increased. Stricter rules If diving against the current, so are concerning the respiratory gas supply to use than the one-third rule described above.

Accessibility of the dive sites

Except in phreatic caves must be traveled to reach the dive site usually a dry part of the cave. In addition to the general risks of cave Befahrung here is added to the transport of equipment: Often routes must overcome schlufend and climbing or equipment are pushed by columns. It is not only danger for man and material, but it can also be damaged speleothems, so diving in remote parts of the cave from the perspective of cave protection can be problematic.

Equipment

In cave diving, greater demands on the diving equipment will be deemed to be filed in recreational diving. Partly also higher requirements than technical diving. Due to the circumstances that prevail During the day, additional, unneeded in the sports and technical diving equipment will be added.

Druckluftflaschen

The entrained air supply is usually greater than in recreational diving. To increase the safety and extend the bottom time, often as technical divers known, several additional bottles ( Stages ) filled with different breathing gas mixtures slung and created bottles depots under water.

Regulators

To be sure if one regulator, multiple redundant regulators per diver will carry with him the rule. Since it is precisely in caves, through which flows of groundwater, can prevail low water temperatures, only cold water usable regulators are generally used.

Diving Suit

In addition to the robustness against abrasion and sharp rock has a wetsuit for cave divers, purified, due to the often fresh water temperatures and sometimes long immersion time, good. A rugged dry suit meets these requirements and additionally provides a redundant buoyancy system.

Dive light

Particular importance is the artificial light source to: Since a loss can be devastating, here multiple redundancy is essential. In the Cavern area will generally require that the diver performs a main and a reserve lamp with it. In the Cave and Full Cave area each diver must carry at least three lamps. In addition to the requirements that apply to all diving lamps, they must be secured in the cave on a helmet in order to have both hands free.

Safety Reel

Each cave divers should carry, with the loss of contact with the permanent main line, it can be found again a safety line role (safety spool reel safety or English ). The minimum required line length hovers around 50 m.

Primary Reel

In addition to the Safety Reel every cave diver should a base line role (English primary reel ) contribute with 80 to 100 m line with him. Thus, a temporary connection is created from a free water surface in the entrance area to the beginning of a permanent mainline (main -line) for the entire duration of the dive.

Jump Reel

For temporary connection at the open gaps left in the main line at junctions ( gaps, jumps ) on or usually several so-called jump reels are taken and used. These usually 20-30 m line.

Directional marker

The guide line must be marked so that the direction to the exit of divers at any time can be found. To serve this purpose so-called directional arrows (English directional markers, line arrows ), which can be integrated into the cable. Particularly if the diver has lost its way, it is important that he can tell by the mark if he moved towards in the direction of output or to the cave interior.

Non directional marker

Next so-called non - directional markings (non directional markers ) are used to mark attendance. Since these have the form of a round biscuit, they are also called cookies ( German Biscuit ').

Helmet

From cave divers is also used in reference to the dry caves driving on a helmet. This is something akin to a mountaineer and is also used to attach the lamp.