Solo diving

Solo diving is the practice of self-sufficient underwater diving without a "dive buddy", particularly with reference to scuba diving, but the term is also applied to freediving. Professionally, solo diving has always been an option which depends on operational requirements and risk assessment. Surface supplied diving and atmospheric suit diving are commonly single diver underwater activities but are accompanied by an on-surface support team dedicated to the safety of the diver, including a stand-by diver, and are not considered solo diving in this sense.
Solo freediving has occurred for millennia as evidenced by artifacts dating back to the ancient people of Mesopotamia when people dived to gather food and to collect pearl oysters. It wasn't until the 1950s, with the development of formalised scuba diving training, that recreational solo diving was deemed to be dangerous, particularly for beginners. In an effort to mitigate associated risks, some scuba certification agencies incorporated the practice of buddy diving into their diver training programmes. The true risk of solo diving relative to buddy diving in the same environmental conditions has never been reliably established, and may have been significantly overstated by some organisations, though it is generally recognised that buddy and team diving, when performed as specified in the manuals, will enhance safety to some extent depending on circumstances.
Some divers, typically those with advanced underwater skills, prefer solo diving over buddy diving and acknowledge responsibility for their own safety. One of the more controversial reasons given being the uncertain competence of arbitrarily allocated dive buddies imposed on divers by service providers protected from liability by waivers. Others simply prefer solitude while communing with nature, or find the burden of continuously monitoring another person reduces their enjoyment of the activity, or engage in activities which are incompatible with effective buddy diving practices, and accept the possibility of slightly increased risk, just as others accept the increased risk associated with deeper dives, planned decompression, or penetration under an overhead.
The recreational solo diver uses enhanced procedures, skills and equipment to mitigate the risks associated with not having another competent diver immediately available to assist if something goes wrong. The skills and procedures may be learned through a variety of effective methods to achieve 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 agencies that will train and certify experienced divers skilled in self-sufficiency and the use of redundant backup scuba equipment. In most countries there is no legal impediment to solo recreational diving, with or without certification.

Definition

Solo diving is defined as diving planned to be conducted entirely or partly without a buddy. The term may also be applied to dives that begin with a buddy but continue after separation, and to dives where other divers are nearby but are either not responsible for the safety of the solo diver, or known not to be competent to deal with the consequences of a foreseeable contingency. The term has also been used to describe dives where buddies are insufficiently attentive or close enough to function effectively as a buddy pair, a situation commonly referred to as "same ocean buddy diving". The term is not used for diving where at least one of the buddies consistently strives to remain together and assist the other in an emergency, but fails in one or both of these goals, or dives where a buddy pair is split by a developing emergency which they are unable to manage.

Self-sufficiency

To be acceptably safe, solo divers must be self-sufficient, well trained, prepared, practiced and prudent. They should have a completely redundant set of all life support equipment - a complete, self-contained backup breathing gas supply sufficient to return to the surface from any point of the planned dive profile. In addition, responsible solo divers adhere to a relatively conservative dive profile, both in depth and level of difficulty. Unlike the buddy system, which can encourage divers to rely on others in the event of an emergency, solo diving encourages divers to prepare themselves to overcome emergencies by their own efforts. The divers who engage in solo diving are typically those who are experienced, equipped and skilled enough to handle problems themselves. Solo divers must feel comfortable and relaxed in doing this sort of diving, and nobody should seriously consider diving solo if they are not both competent and comfortable in doing so.

History

The history of solo diving stands in stark contrast to the relatively new concept of buddy diving that was developed for recreational diving in the early to mid-20th century. Artifacts dating back some 4,500 years provide evidence of solo diving for food and commerce by the ancient people of Mesopotamia. There are written accounts from the 2nd century BC that describe commercial sponge fishing, including notes about sponge divers, their lifestyle and fear of predatory sharks. In 350 BC, Aristotle wrote about "an 'elephant nose-like tube' that allowed sponge fishermen to breathe during diving", and in 8th–6th century BC, there are references to solo diving in the writings of Homer.
Freedivers traditionally dived alone or with an attendant on the surface to assist with the harvest, and many of the early diving bells were only large enough for a single occupant. When surface supplied diving was first developed, it was common to have only one diver unless the work required more. Those early traditions continue and customarily include a standby diver, and a working diver who is in constant communication with the surface control crew. The sport of scuba diving is rooted in a multitude of small enthusiastic snorkelling and spearfishing clubs that date back to the decades just before and after World War II. In the late 1940s, after the invention of the Aqua-lung by Cousteau and Gagnan, the first retail underwater breathing apparatus for sport was commercially marketed. As the sport expanded through the 1950s, several sporting organisations – notably the Young Men's Christian Association – began scuba training programmes for swimming enthusiasts, thus began the codification of what was believed to be proper practices for the expanding amateur sport of scuba diving. The buddy system was thought to be a useful corollary to the "never swim alone" edicts of the YMCA swimming and lifesaving programmes. Cousteau independently implemented a buddy system after a number of harrowing diving incidents that date back to the earliest days of exploratory scuba diving. The buddy system's useful aspects have long been established, including the cross-checking of equipment before dives, the facilitating of assistance for possible entanglement problems or equipment failures, and enhancement of the social nature of diving. The YMCA was a substantial influence in the development of diver certification during the first 50 years of the sport. As various scuba programmes were adopted by emerging scuba certification agencies, such as the National Association of Underwater Instructors, Professional Association of Diving Instructors, and British Sub-Aqua Club, the practise of buddy diving inspired one of the two main mantras of recreational scuba: "never hold your breath" and "never dive alone".
By the early to mid-1990s, solo divers became more visible and increasingly open about their alternative dive safety philosophy, despite the recreational industry's established adherence to the buddy system. It wasn't until 2001 that Scuba Diving International initiated formal certification training specifically for solo diving. Several other agencies eventually followed suit with certificates titled Self-reliant Diver and variations of that theme; all with the intention of improving diver competence without necessarily going solo, and recognising that the buddy system does not always comply with the ideal. At the 2012 "Rebreather Forum 3", a significant minority of attendees were of the opinion that, in some circumstances, it would be acceptable to dive solo on rebreathers.

Reasons for solo scuba diving

The intention of using the buddy system when scuba diving is to improve the chances of avoiding or surviving accidents in or underwater. Diving together in close groups of two or sometimes three divers, and co-operating with each other to help or perform a rescue in an emergency situation may save a life; however, it is most effective when each buddy is competent in all the relevant skills and remains consistently and sufficiently aware in order to respond in time.
Some divers, such as instructors, are effectively acting as self-sufficient divers because they dive with students who may not yet be trained in or capable of rescue. Others, such as underwater photographers and videographers, dive solo as it allows them to focus more on capturing selected images rather than relying on buddies to remain close at hand. Photographers or videographers who dive with buddies are often effectively "same ocean" buddies, implying they may be far enough apart physically, or sufficiently focused on their camera-related tasks, to be ineffective as a designated dive buddy. This practice has led to many highly experienced underwater photographers diving solo since they don't commit to provide timely support to a buddy nor expect such support from a buddy. Underwater hunters often elect to dive solo in order to focus on their prey.
Solo diving was considered technical diving by most recreational diver certification agencies and discouraged as more dangerous than buddy diving, but many experienced divers and some certification agencies consider it an acceptable practice for suitably trained, equipped, and competent recreational divers; some others consider it occasionally inevitable. In place of relying on the buddy diving safety system, solo divers try to be self-sufficient and are willing to take responsibility for their own safety while diving. The first training agency to offer a Solo diver certification was SDI in 1999. In 2011, the Professional Association of Diving Instructors started offering a solo specialty called "Self-Reliant Diver", which in many respects is very similar to the course offered by SDI.
In professional diving, solo diving is normal procedure when one diver is sufficient to perform the required task, particularly on surface supplied equipment, to the extent that it is not even noted as an exception. However, a standby diver is required at the surface or at the bell, the working diver must be in communication with the supervisor at the surface, and the diver's airway is relatively secure in a helmet or full-face mask. Procedures for the dive are based on assessed risk.
In recreational diving, solo diving is an option chosen by the diver, for any combination of several reasons.

Solo divers don't need to work around a buddy's diving schedule, and can dive when no trusted and familiar buddy is available.
Some divers will dive in a buddy pair if diving with a known and trusted buddy but otherwise dive solo in preference to being paired up with a potentially unreliable, incompetent, or otherwise dangerous partner. In the United States, the added risk of becoming a respondent in litigation in the event of a diving accident with such a "dangerous buddy" can be a motivation to dive alone.
The diver may simply prefer to dive alone. Diving professionals Wes Skiles and Ken Loyst, among others, take pleasure in the solitude of solo diving and in the feeling of self-sufficiency for this style of diving, that one is not dependent on others, but is relying solely on one's own skills and capabilities. Other experienced professionals, including Bret Gilliam and Darren Webb, enjoy the sense of freedom, of not being impeded by the need to look after anyone but oneself and therefore being able to achieve one's own goal in the dive without compromising.
There are divers who enjoy specific underwater activities but are unable to find anyone who shares the specific interest sufficiently to dive with them, and where the activity is incompatible with a less than dedicated buddy. The option of simply not diving is not a practical solution, as the diver is then almost permanently prevented from pursuing the interest. Diving with buddies who get bored or tired quickly also does not lead to enhanced enjoyment for either party. When the underwater activity is of interest only to one person, diving solo is the only option that allows the activity to be undertaken.
When photographing or shooting video of shy animals which are easily disturbed, it is more likely to be successful if there is only one diver potentially disturbing the subjects. The disturbance can also be reduced by buddy diving on rebreathers, which cuts down on bubble noise, but at the cost of increased risk due to the inherently higher number of failure modes characteristic of rebreathers. It is not clear which system has the lower overall risk.
Most scuba depth records are set by solo divers. There is usually a substantial backup team on site and standing by, but for the record breaking part of the dive, the diver is almost always alone, and beyond the reasonable expectation of rescue.