Cave Diving has a relatively small number of participants in the UK and although it has developed over a period of 70 years, there are insufficient incidents of failure to conduct a robust quantitative analysis of failure patterns. Outside the UK there is more information on failure patterns available, however the difference in the nature of the UK sump environment and the non- UK sump environments do not permit direct comparisons. With this caveat in mind, it is still useful to look at cave diving fatalities outside the UK. In 1999, International Underwater Cave Rescue & Recovery published an Accident Analysis on 478 cave diving fatalities . Of those 478 only 47 were cave trained. This emphasises the obvious need for adequate training. Of the 40 cave trained fatalities where a cause was determined, the top most frequent causes quoted were, in order:
- Adv equipment
- Line gap
- Gas mixture problem
Due to the relatively shallow nature of UK sumps, depth and gas mixture are unlikely to be the major hazard in the UK. Solo diving is an issue outside the UK but this is because the non- UK cave diving training schemes do not prepare divers for solo cave diving. From this information it is probable that the most significant hazards in UK sump diving include, in no particular order:
- Line management
It is relevant to show that solo cave diving does not aggravate the risks associated with the major hazards of cave diving where buddy diving might mitigate the risks.
Controlling the hazards and risks associated with cave diving equipment is the responsibility of the individual diver
Training is a key part of the CDG’s approach to cave diving. The CDG contributes to this area by the production of The Cave Diving Group Manual . Additionally, the CDG has issued a Training Standard  to help guide both internal and external agencies in their delivery of suitable training for UK conditions. The CDG is a relatively small organisation with a limited capability to deliver training directly. It does however have a very strong ethos of training by example or mentoring more junior divers. This philosophy is described in the Cave Diver Education programme . There is no evidence that buddy diving has a significantly beneficial affect on the delivery of effective training.
Controlling the hazards and risks associated with cave diving equipment is the responsibility of the individual diver. The CDG’s training and mentoring philosophy provides individual CDG divers with a large resource of experience to draw on when selecting and maintaining their equipment. This area is essential to safe cave diving and is strongly emphasised by the CDG. There is also a strong philosophy of complete redundancy for all critical systems. There is no evidence that buddy diving has a significantly beneficial affect on the safety of diving equipment.
The third major hazard area is line management. The difficulties of laying and managing good lines to guide divers in UK sumps are enormous. Over the years this area of UK cave diving has been extensively researched. The first comprehensive review of this area was published by the CDG in 1981 in “Line Laying and Following” by Geoff Yeadon . This pivotal reference has formed the basis of modern line laying and management. This is an area that is constantly evolving and new methods are regularly published in the quarterly CDG Newsletter. There is no evidence that buddy diving has a significantly beneficial affect on the safety of line laying and management.
The first British Sump Rescue Symposium held in 1986 looked at the issue of cave diving safety . The published proceedings on Safe Cave Diving identified the technique of solo cave diving and strongly advocated “the need for the cave diver to learn independence and to feel, when he is diving, that he is entirely on his own.” The advantages of buddy diving derive from promoting mutual self- help and aiding safety via the surface. Neither of these advantages is applicable to UK cave diving. The symposium advocated an intelligent approach to cave diving; “The most important piece of equipment the diver has is his brain. If he fully understands the implications of a dive an experienced diver will either take the necessary precautions or postpone the dive until he has gained the required knowledge, equipment or skill”.
Diving with multiple concurrent divers does have a role to play in UK cave diving. There are certain tasks, such as underwater construction, that benefit from more than one diver being present at the same time. Additionally, there is a social dimension to recreational cave diving that results in more than one diver entering a sump at the same time. This is particularly likely if a caving project is conducted beyond a sump where mutual support may be critical to the success of a task. The overriding philosophy of the CDG remains that once you enter a UK sump you bear the full responsibility and accountability for your own actions. As such there is a deeply ingrained belief that a philosophy of solo cave diving is an essential requirement for safe sump diving within the UK. Multiple concurrent divers are effectively a team of solo divers, where each individual diver must be considered by all of the divers as a potential source of hazard. This form of diving is more accurately thought of as team solo diving.
Buddy diving is very different from team solo diving. In buddy diving a pair of divers are considered to be a unit and thus share responsibility and accountability for their actions. Buddy diving has been developed and modified for many different environments including some cave environments. It would, however, be a grave and possibly fatal error to use an unmodified buddy diving system in the majority of UK sumps. Similarly it would be incorrect for a diver familiar with team solo diving to consider themselves fully conversant with buddy diving or to consider that solo cave diving is appropriate for all forms of diving.
There are clear additional hazards introduced by buddy diving and yet there is no clear reduction in the risks from the major hazards in cave diving gained through buddy diving. The Cave Diving Group recommends that solo and team solo diving are appropriate techniques for use in the exploration of UK sumps.