Solo diving

Solo diving is the practice of underwater diving alone without a "dive buddy", particularly with reference to scuba diving, but the term is also applied to freediving. Surface supplied diving and atmospheric suit diving are frequently done by a single diver, but there is a support team on the surface dedicated to the safety of the diver in those cases, and the term is not generally applied. It is a practice which has occurred throughout the history of diving but since the development of formalised recreational diver training, it was deemed by some recreational certification agencies to be unacceptably dangerous, and the practice of buddy diving has been recommended as a means of mitigating the solo diving risks. However buddy diving brings its own set of risks and inconveniences, and some divers elect to dive solo to avoid these problems. Solo diving is practiced for several reasons - some practical, and some philosophical.

In professional scuba diving, solo diving has always been considered an option when it is most appropriate to the operational requirements and the risks have been assessed to be acceptable under the circumstances. However, this usually involves voice or line communications with the surface control point, and a surface standby diver available to go to the assistance of the working diver at very short notice. These options are seldom available to the recreational diver.

The recreational solo diver uses enhanced procedures, skills and equipment to mitigate the risks associated with not having another diver immediately available to assist if something goes wrong. The skills and procedures may be learned by any effective method which provides the appropriate competence, including formal training programmes with associated assessment and certification. Recreational solo diving, once discouraged by most training agencies, has been accepted since the late 1990s by some training agencies for experienced divers who have skills in self-sufficiency and redundant backup equipment.

Solo diving has been defined as a dive planned to be conducted entirely or partly without a buddy. However it is also applied to dives which were intended to be conducted with a buddy, but were continued after buddy separation, and to dives in which there may be other divers present in the immediate vicinity, but none of them are responsible for the safety of the solo diver, or none of them are competent to deal with the consequences of a reasonably foreseeable contingency. It has even been applied to dives where the buddies are insufficiently attentive or close enough to function effectively as a buddy pair, more commonly referred to a "same ocean buddy diving".

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