Recreational diving

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Beginner diver in St. Croix, United States Virgin Islands Discover Scuba Diving -- St. Croix, US Virgin Islands.jpg
Beginner diver in St. Croix, United States Virgin Islands

Recreational diving or sport diving is diving for the purpose of leisure and enjoyment, usually when using scuba equipment. The term "recreational diving" may also be used in contradistinction to "technical diving", a more demanding aspect of recreational diving which requires more training and experience to develop the competence to reliably manage more complex equipment in the more hazardous conditions associated with the disciplines. [nb 1] [1] Breath-hold diving for recreation also fits into the broader scope of the term, but this article covers the commonly used meaning of scuba diving for recreational purposes, where the diver is not constrained from making a direct near-vertical ascent to the surface at any point during the dive, and risk is considered low.

Contents

The equipment used for recreational diving is mostly open circuit scuba, though semi closed and fully automated electronic closed circuit rebreathers may be included in the scope of recreational diving. Risk is managed by training the diver in a range of standardised procedures and skills appropriate to the equipment the diver chooses to use and the environment in which the diver plans to dive. Further experience and development of skills by practice will improve the diver's ability to dive safely. Specialty training is made available by the recreational diver training industry and diving clubs to increase the range of environments and venues the diver can enjoy at an acceptable level of risk.

Reasons to dive and preferred diving activities may vary during the personal development of a recreational diver, and may depend on their psychological profile and their level of dedication to the activity. Most divers average less than eight dives per year, but some total several thousand dives over a few decades and continue diving into their 60s and 70s, occasionally older. Recreational divers may frequent local dive sites or dive as tourists at more distant venues known for desirable underwater environments. An economically significant diving tourism industry services recreational divers, providing equipment, training and diving experiences, generally by specialist providers known as dive centers, dive schools, live-aboard, day charter and basic dive boats.

Legal constraints on recreational diving vary considerably across jurisdictions. Recreational diving may be industry regulated or regulated by law to some extent. The legal responsibility for recreational diving service providers is usually limited as far as possible by waivers which they require the customer to sign before engaging in any diving activity. The extent of responsibility of recreational buddy divers is unclear, but buddy diving is generally recommended by recreational diver training agencies as safer than solo diving, and some service providers insist that customers dive in buddy pairs. The evidence supporting this policy is inconclusive.

Scope

Scuba diver in Panama Diver and anemone, Monito Island, Puerto Rico.jpg
Scuba diver in Panama

Recreational diving may be considered to be any underwater diving that is not occupational, professional, or commercial, in that the dive is fundamentally at the discretion of the diver, who dives either to their own plan, or to a plan developed in consensus with the other divers in the group, though dives led by a professional dive leader or instructor for non-occupational purposes are also legally classified as recreational dives in some legislations. [2] [3] [4]

The full scope of recreational diving includes breath-hold diving and surface supplied diving – particularly with lightweight semi-autonomous airline systems such as snuba – and technical diving (including penetration diving), as all of these are frequently done for recreational purposes, but common usage is mostly for open water scuba diving with limited decompression.

Scuba diving implies the use of an autonomous breathing gas supply carried by the diver, the self-contained underwater breathing apparatus which provides the name for this mode of diving. Scuba may be the simpler and more popular open circuit configuration or one of the more complex and expensive closed or semi-closed rebreather arrangements. Rebreathers used for recreational diving are generally designed to require a minimum task loading on the diver and as far as possible to fail safe and give the diver ample warning to bail out to open circuit and abort the dive.

Open water is the definitive environment for recreational diving, and in this context implies that there is no physical or physiological barrier to the diver concluding the dive at any time by a direct ascent to the surface, either vertically, or via a clearly visible route adequately illuminated by ambient light. Some organisations extend the scope of recreational diving to allow short decompression obligations which can be done without gas switching. Depth limitations are imposed by the certification agencies, and relate to the competency associated with the specific certification. Entry level divers may be restricted to a depth of 18 or 20 metres (59 or 66 ft), and more advanced divers to 30, 40, 50 or 60 m depending on the certification and agency. Junior divers may be restricted to shallower depths generally confined to a depth of 12 metres (40 ft). [5]

Recreational diving is generally limited to the use of air or a single nitrox mixture with an oxygen fraction not exceeding 40% for the planned dive, but this does not preclude constant oxygen partial pressure nitrox provided by electronically controlled closed circuit rebreathers like the Poseidon Mk6 or variable nitrox mixtures such as provided by the earlier semi-closed circuit Dräger Ray rebreather. Emergency gas supplies are either by sharing with a dive buddy or from a bailout cylinder for open circuit diving, and by bailout to open circuit for rebreather diving.

Most recreational diving officially applies the buddy system, but in reality there are a significant proportion of dives which are either effectively solo dives or where larger groups of nominally paired divers follow a dive leader and may be escorted by another dive leader.

Reasons to dive

The reasons to dive for recreational purposes are many and varied, and many divers will go through stages when their personal reasons for diving change, as the initial novelty of the alien environment becomes familiar and skills develop to the point where the diver is able to pay more attention to the surroundings.

Many people start diving for the adventure of experiencing a different environment and the ability to maneuver fairly freely in three dimensions, but the novelty wears off after a while. This may be replaced by the satisfaction of developing the skills to operate in a wider range of environments, and developing excellence in those skills, the addition of compatible interests and activities to complement the basic activity, like underwater photography and an interest in the details of the environment, including exploration and study and recording of aspects of the environment. [6] Experience of the underwater environment varies depending on where the diver has access to suitable sites - there is more to see on a coastal reef than in most freshwater lakes, and scuba diving tourism can make a wide variety of more entertaining and challenging sites available. Exploration can also extend beyond tourism to the search for previously unvisited sites and the satisfaction of being the first to be there and in some cases, tell the story.

Reasons to dive include:

Activities

Free diver (breath hold) in Cyprus Junko-Kitahama Apnea-Monofin cropped.jpg
Free diver (breath hold) in Cyprus
Freediving while snorkeling in shallow water, Red Sea Unterwasserfotograf DSCF9999VE.jpg
Freediving while snorkeling in shallow water, Red Sea

There are many recreational diving activities, and equipment and environmental specialties which require skills additional to those provided by the entry level courses, These skills were originally developed by trial and error, but training programmes are offered by most diver training agencies for the convenience of the diver, and profit for the agency, or in the case of club oriented systems, for the overall benefit of the club communuty:

Activities:

Specialties

Some recreational diving activities require skills sufficiently beyond the basic recreational open water diving skill set that they are classed by the recreational diver training industry as specialties, and for which further training and certification is available. These can be broadly distinguished as environmental and equipment specialties.

Environmental specialties:

Equipment specialties:

Many diver training agencies such as ACUC, BSAC, CMAS, IANTD, NAUI, PADI, PDIC, SDI, and SSI offer training in these areas, as well as opportunities to move into professional dive leadership, instruction, technical diving, public safety diving and others.

History

The invention of the aqua-lung in 1943 led to modern recreational diving Espalion - Musee du Scaphandre (22).jpg
The invention of the aqua-lung in 1943 led to modern recreational diving

Recreational scuba diving grew out of related activities such as Snorkeling and underwater hunting. [15] For a long time, recreational underwater excursions were limited by breath-hold time. The invention of the aqualung in 1943 by Émile Gagnan and Jacques-Yves Cousteau and the wetsuit in 1952 by University of California, Berkeley physicist, Hugh Bradner [16] and its development over subsequent years led to a revolution in recreational diving. [15] However, for much of the 1950s and early 1960s, recreational scuba diving was a sport limited to those who were able to afford or make their own kit, and prepared to undergo intensive training to use it.[ citation needed ]

As the sport became more popular, manufacturers became aware of the potential market, and equipment began to appear that was easy to use, affordable and reliable. Continued advances in SCUBA technology, such as buoyancy compensators, improved diving regulators, wet or dry suits, and dive computers, increased the safety, comfort and convenience of the gear encouraging more people to train and use it.

Until the early 1950s, navies and other organizations performing professional diving were the only providers of diver training, but only for their own personnel and only using their own types of equipment. The first scuba diving school was opened in France to train the owners of the Cousteau and Gagnan designed twin-hose scuba.[ citation needed ] The first school to teach single hose scuba was started in 1953, in Melbourne, Australia, at the Melbourne City Baths. RAN Commander Batterham organized the school to assist the inventor of the single hose regulator, Ted Eldred.[ citation needed ] However, neither of these schools was international in nature.

There were no formal training courses available to civilians who bought the early scuba equipment. Some of the first training started in 1952 at the Scripps Institution of Oceanography where Andy Rechnitzer, Bob Dill and Connie Limbaugh taught the first scuba courses in the United States, [17] then in 1953 Trevor Hampton created the first British diving school,[ citation needed ] the British Underwater Centre and in 1954 when Los Angeles County [18] created an Underwater Instructor Certification Course based on the training that they received from the scientific divers of the Scripps Institution of Oceanography. Early instruction developed in the format of amateur teaching within a club environment, as exemplified by organizations such as the Scottish Sub Aqua Club and the British Sub Aqua Club from 1953, Los Angeles County from 1954 and the YMCA from 1959. [19]

Professional instruction started in 1959 when the non-profit NAUI was formed, [20] which later effectively was split, [21] to form the for-profit PADI in 1966. [22] The National Association of Scuba Diving Schools (NASDS) started with their dive center based training programs in 1962 followed by SSI in 1970. [23] Professional Diving Instructors College was formed in 1965, changing its name in 1984 to Professional Diving Instructors Corporation (PDIC). [24]

In 2009 PADI alone issued approximately 950,000 diving certifications. [25] Approximately 550,000 of these certifications were "entry level" certifications and the remainder were more advanced certifications.

Scuba-diving has become a popular leisure activity, and many diving destinations have some form of dive shop presence that can offer air fills, equipment sale, rental and repair, and training. In tropical and sub-tropical parts of the world, there is a large market for 'holiday divers'; people who train and dive while on holiday, but rarely dive close to home.[ citation needed ]

Technical diving and the use of rebreathers are increasing, particularly in areas of the world where deeper wreck diving is the main underwater attraction.[ citation needed ] Generally, recreational diving depths are limited by the training agencies to a maximum of between 30 and 40 meters (100 and 130 feet), beyond which a variety of safety issues such as oxygen toxicity and nitrogen narcosis significantly increase the risk of diving using recreational diving equipment and practices, and specialized skills and equipment for technical diving are needed.[ citation needed ]

Standard equipment

Scuba diver wearing a dry suit in a kelp forest off Point Lobos, California Scuba diver in kelp forest.jpg
Scuba diver wearing a dry suit in a kelp forest off Point Lobos, California

The standard recreational open circuit scuba equipment includes the following items:

Basic equipment, which can be used for most modes of ambient pressure diving:

A scuba set, comprising:

Auxiliary equipment to enhance safety.

For solo diving a bailout cylinder is considered standard for dives where there is an appreciable risk of entrapment, or where a direct controlled emergency swimming ascent is not an acceptable option to manage an out-of-air incident at any point in the planned dive profile.

Standard procedures

Divers making a recommended shallow stop during ascent to the surface DiveTulsa (2062961046).jpg
Divers making a recommended shallow stop during ascent to the surface

Some skills are generally accepted by recreational diver certification agencies as necessary for any scuba diver to be considered competent to dive without direct supervision, [26] and others are more advanced, though some diver certification and accreditation organizations may consider some of these to also be essential for minimum acceptable entry level competence. Divers are instructed and assessed on these skills during basic and advanced training, and are expected to remain competent at their level of certification, either by practice or refresher courses.

The skills include selection, functional testing, preparation and transport of scuba equipment, dive planning, preparation for a dive, kitting up for the dive, water entry, descent, breathing underwater, monitoring the dive profile (depth, time and decompression status), personal breathing gas management, situational awareness, communicating with the dive team, buoyancy and trim control, mobility in the water, ascent, emergency and rescue procedures, exit from the water, un-kitting after the dive, cleaning and preparation of equipment for storage, and recording the dive, within the scope of the diver's certification. [26] [27] A significant amount of harmonization of training standards and standard and emergency procedures has developed over the years, largely due to organisations like World Recreational Scuba Training Council. This allows divers trained by the various certifying organisations to dive together with a minimum of confusion, which enhances safety. Diver communications is a particular aspect where most of the basic hand signals are common to most recreational diver training agencies. [28]

This does not mean that there is no variation. There are some procedures such as emergency donation of air which are quite strongly polarized between those who advocate donation of the secondary (octopus) regulator and those who advocate donating the primary regulator. [29] Length of regulator hose and position of the secondary second stage depend on the donation technique.

There are also variations in procedures for self rescue in an out-of-air situation, and in procedures for bringing an unresponsive casualty to the surface. [30]

Solo diving, once considered technical diving and discouraged by most certification agencies, is now seen by many experienced divers and some certification agencies [31] as an acceptable practice for those divers suitably trained and experienced. [32] Rather than relying on the traditional buddy diving safety system, solo divers rely on self-sufficiency and are willing to take responsibility for their own safety while diving. [31]

Buddy diving is the more generally advocated procedural alternative, on the principle that in case of an emergency, a dive buddy can assist the diver in difficulty, but this is only valid if the buddy is close enough to help, notices the problem, and is competent and willing to assist. [33]

Training

Diver off Carmen, Philippines Punta Diwata Reef.jpg
Diver off Carmen, Philippines

Many recreational diver training organisations exist, throughout the world, offering diver training leading to certification: the issuing of a "diver certification card", also known as a "C-card," or qualification card.

Recreational diver training courses range from minor specialties which require one classroom session and an open water dive, and which may be completed in a day, to complex specialties which may take several days to weeks, and require several classroom sessions, confined water skills training and practice, and a substantial number of open-water dives, followed by rigorous assessment of knowledge and skills. Details on the approximate duration of training can be found on the websites of most certification agencies, but accurate schedules are generally only available from the specific school or instructor who will present that course, as this will depend on the local conditions and other constraints.

Diving instructors affiliated to a diving certification agency may work independently or through a university, a dive club, a dive school or a dive shop. They will offer courses that should meet, or exceed, the standards of the certification organisation that will certify the divers attending the course.

Diving skills

Diver training can be divided into entry level training, which are those skills and knowledge considered essential for the diver to dive unsupervised at an acceptably low level of risk by the certifying agency, and further skills and knowledge which allow better performance and extend the environmental capacity and equipment choices of the diver.

Entry level

There is a significant variation in entry level training, with some training agencies requiring the bare minimum as specified by RSTC and ISO, and others requiring a greater level of competence with associated assumption of lower risk to the diver and dive buddy, and less likelihood of environmental damage. Entry level training may include skills for assisting or rescue of another diver, but this is not always the case. Divers without rescue training are routinely assigned to dive as buddy pairs to follow organizational protocols. This is not generally a contravention of the training agencies' recommendations.

The initial training for open water certification for a person who is medically fit to dive and a reasonably competent swimmer is relatively short. The minimum number of open-water dives required for certification is usually four, but instructors are generally required by training standards to ensure that the diver is sufficiently skilled to dive safely in the local environment before certification is issued, and this may require further training and experience beyond the required minimum. Many dive shops in popular holiday locations offer courses intended to teach a novice to dive in a few days, which can be combined with diving on the vacation. Other instructors and dive schools will provide more thorough training, which generally takes longer.

Beyond entry level

Skills and knowledge beyond the minimum requirement are generally labelled Advanced skills, and these may include skills such as competent buoyancy control, which are included in the entry level skills by other agencies. Many skills which are considered advanced by recreational training agencies are considered basic entry-level skills for professional divers. [34]

Training standards

Scuba diving education levels as used by ISO: PADI, CMAS, SSI and NAUI Scuba education levels.svg
Scuba diving education levels as used by ISO: PADI, CMAS, SSI and NAUI

Each diver certification agency has its own set of diver training standards for each level of certification that they issue. Although these standards are usually available on request or on the organisation's website, the assessment criteria are often not available to the public, making a direct comparison of standards difficult. Most agencies comply with the minimum requirements of the World Recreational Scuba Training Council (WRSTC) or ISO for the relevant certification (ISO 24801-2 Autonomous diver, [35] and ISO 24801-3 Dive leader [36] ), but most certification levels are not defined by the international standards. [37]

Under most entry-level programs (SEI, SDI, PADI, BSAC, SSAC, NAUI, SSI, and PDIC), divers can complete a certification with as few as four open water dives. This complies with the minimum requirements of ISO 24801-2 Autonomous diver. [35] Such a qualification allows divers to rent equipment, receive air fills, and dive without supervision to depths typically restricted to 18 meters (60 feet) with an equally qualified buddy in conditions similar to, or easier than those in which they were trained. [35] Certification agencies advise their students to dive within the scope of their experience and training, and to extend their training to suit the conditions in which they plan to dive.

In the 1980s, several agencies[ who? ] with DEMA collaborated to author ANSI Standard Z86.3 (1989), Minimum Course Content For Safe Scuba Diving which defines their training as the Accepted Industry Practices.[ citation needed ] The International Standards Organisation has since published ISO 24801 and ISO 24802 which define minimum training standards for two levels of recreational diver and for recreational diving instructors. [35]

A few recreational certification agencies such as GUE, [38] and the commercial diver training standards of several countries, including the United Kingdom, Australia, South Africa, and Canada, consider the competence provided by the recreational diver training industry minimum standard to be inadequate for safe diving, particularly occupational diving, where the diver has a legal duty of care towards other members of the dive team, even though the responsibility for occupational dive planning and safety is held by a professional diving supervisor. [4] [39]

Risk

Recreational scuba diving involves physical and psychological risks and therefore can be classified as an extreme sport. [40] Fatality rates of 16.4 deaths per 100,000 persons per year among DAN America members and 14.4 deaths per 100,000 persons per year the British Sub-Aqua Club (BSAC) members were similar and did not change during 2000–2006. This is comparable with jogging (13 deaths per 100,000 persons per year) and motor vehicle accidents (16 deaths per 100,000 persons per year), and within the range where reduction is desirable by Health and Safety Executive (HSE) criteria. [41]

Data for 17 million student-diver certifications during 63 million student dives over a 20-year period from 1989 to 2008 show a mean per capita death rate of 1.7 deaths per 100,000 student divers per year. This was lower than for insured DAN members during 2000–2006 at 16.4 deaths per 100,000 DAN members per year, but fatality rate per dive is a better measure of exposure risk, A mean annual fatality rate of 0.48 deaths per 100,000 student dives per year and 0.54 deaths per 100,000 BSAC dives per year and 1.03 deaths per 100,000 non-BSAC dives per year during 2007. The total size of the diving population is important for determining overall fatality rates, and the population estimates from the 1990s of several million U.S. divers need to be updated. [41]

The most frequent root cause for diving fatalities is running out of or low on gas. Other factors cited include loss of buoyancy control, entanglement or entrapment, rough water, equipment misuse or problems, and emergency ascent, which is often a response to a breathing gas problem. The most common injuries and causes of death were drowning or asphyxia due to inhalation of water, air embolism and cardiac events. Risk of cardiac arrest is greater for older divers, and greater for men than women, although the risks are equal by age 65. [41]

Several plausible opinions have been put forward but have not yet been empirically validated. Suggested contributing factors included inexperience, infrequent diving, inadequate supervision, insufficient predive briefings, buddy separation, and dive conditions beyond the diver's training, experience, or physical capacity. [41]

Ascending towards a dive boat, Hout Bay, South Africa Divers under the boat at Hout Bay MG 4368 a.jpg
Ascending towards a dive boat, Hout Bay, South Africa

Legal constraints on recreational diving vary considerably across jurisdictions. In many countries recreational diving is either not mentioned at all in laws and regulations, or specifically excluded from regulations covering occupational diving. [4] In others, only diver training and dive-leading activities where the diver is either employed or takes a leadership position where they are responsible for the safety of others is covered by legislation. [3] At the other extreme, countries such as Israel have statutory law covering all recreational diving activities. [42]

Recreational diver training and dive leading are industry regulated in some countries, and only directly regulated by government in a subset of them. In the UK, HSE legislation includes recreational diver training and dive leading for reward; [3] in the US and South Africa industry regulation is accepted, though non-specific health and safety legislation still applies. [2] [4] In Israel recreational diving activities are regulated by the Recreational Diving Act, 1979. [42]

The legal responsibility for recreational diving service providers is usually limited as far as possible by waivers which they require the customer to sign before engaging in any diving activity. The extent of responsibility of recreational buddy divers is unclear and has been the subject of considerable litigation. It is probable that it varies between jurisdictions. In spite of this lack of clarity, and conflicting evidence, buddy diving is recommended by recreational diver training agencies as safer than solo diving, and some service providers insist that customers dive in buddy pairs. [43] [44] [45]

Economic impact

Recreational diving provides a market for the diving equipment industry, the diver training industry and the diver services industry, all of which are interdependent, and at retail level, frequently provided by the same local specialist outlet.

The combined contribution of recreational scuba diving and snorkeling to the US gross domestic product was estimated at $11 billion in a 2019 report by the Diving Equipment and Marketing Association [46]

Scuba diving tourism is the industry based on servicing the requirements of recreational divers at destinations other than where they live. It includes aspects of training, equipment sales, rental and service, guided experiences and environmental tourism. [47] [48] Customer satisfaction is largely dependent on the quality of services provided, and personal communication has a strong influence on the popularity of specific service providers in a region. [47]

Demographics

A 2014 survey of American divers indicates with a high level of confidence for the specified population, that about 3.145 million Americans (1.1 percent of population) took part in scuba diving at least once in the survey year, which is a 0.9 percent decrease over 2013, but participation increased by 1.3 percent on average for the previous five years. There were about 2.252 million casual participants who made between one and seven dives per year and 893,000 core participants who dived eight or more times per year. 66% of casual and 74% of core participants were male. The age distribution of casual and core participants differs. Core participants tend to be older. Casual participation tends to gradually rise to a peak in early middle age, then drop markedly after about 45 years old, while core participation tends to continue at a relatively consistent rate over age groups up to about 65 years, after which it drops markedly. [49] Some training agencies will accept trainees as young as 8 years old for participation in supervised scuba experiences, [50] and 10 years for certification. [51] The record age for a scuba dive as of January 2020 is 95 years. [52] [53] Recreational scuba divers appear to be on average wealthier and better educated than the general population, as indicated by earlier surveys. There is a greater tendency than average for scuba divers to participate in other sporting and exercise activities than the general population, but lack of adequate physical fitness is frequently cited as a contributory factor in diving accidents. [49] [54]

The medical literature, anecdotal evidence and a small-scale survey suggest that a significant part of the recreational scuba diving population may have chronic medical conditions that affect their fitness to dive according to the Recreational Scuba Training Council's guidelines. [55] This may have an influence on risk, as unfitness and preexisting medical conditions are frequently cited in incident reports where the incident was adequately investigated.

PADI worldwide certification statistics indicate a slow but steady trend of increasing proportion of certification of female divers at all levels from 34.4% in 2013 to 38.0% in 2018, and a decrease in the average age of certifications over the same period. [56]

Personality profiles of recreational divers were analysed in a 2010 study on entry level divers: The participants scored high on self-sufficiency, impulsiveness and boldness and low on warmth, sensitivity and conformity, and differed from the typical extreme sport participant's personality profile. Personality types identified include adventurer, dreamer, rationalist and passive-aggressive macho diver, and results suggested that the risk behaviour likely to be exhibited by the diver would depend on their personality type. [40]

Venues for diving

Most types of bodies of water can be used as dive sites:

Flooded excavations often have low visibility. Disused and flooded quarries are popular in inland areas for diver training as well as recreational diving. Rock quarries may have reasonable underwater visibility - there is often little mud or silt to create mid-water particles that cause low visibility, and the lack of flow allows silt to settle on the bottom, where it may later be kicked up by unskilled divers to temporarily reduce visibility locally. As they are not natural environments, and usually privately owned, quarries may contain objects intentionally placed for divers to explore, such as sunken boats, automobiles, aircraft, or structures like grain silos and gravel chutes. The popularity of a dive site will usually depend on accessibility, known hazards, desirable features, and the variety of alternative options nearby. Sites known for exceptionally desirable features may attract expeditions in spite of major accessibility problems and significant hazards.

Dive site features

Many types of underwater features make an interesting dive site, for example:

NASA image showing locations of significant coral reefs, which are often sought out by divers for their abundant, diverse life forms. Coral reef locations.jpg
NASA image showing locations of significant coral reefs, which are often sought out by divers for their abundant, diverse life forms.

Marine citizen science

Marine citizen science, the scientific research and monitoring projects for which members of the public collect, categorize, transcribe or analyze scientific data, is an increasingly popular but underutilised collaboration between society and scientific research, [57] in which members of the recreational scuba diving community actively participate in marine data acquisition and recording, largely by way of geolocated photographic observations collected during recreational dives, but also in more structured and long term experimental work. Some barriers exist between divers and projects that are beyond the control of either the divers or the project organisers, but other aspects such as access to projects and feedback after participation are amenable to improvement. Recreational scuba divers are generally well disposed towards marine science, and participation could be improved by better management. Stakeholders to be considered are the scuba diving industry and professional intermediaries. [58]

Citizen science can be an effective approach to marine and coastal conservation, and methods of making better use of citizen input for projects relating to policy, education, community capacity building, site management, species management, and research. have been investigated and developed. Marine citizen science projects face different challenges to terrestrial systems. The main challenges are logistical, as people spend very little time in the water. Access often requires expensive boats, diving gear, or transportation to the coast, and safety and liability issues can be complicated. Using citizen scientists can economically increase the temporal and spatial scale of a project. Early involvement of divers in the planning of a project can increase buy-in and avoid errors due to inaccurate assessment of capabilities and interest of volunteers. Training and some field oversight by professionals will usually be necessary to ensure reliable data collection. Retention of volunteers is affected by their perception of the recognition of the value of their work. [57]

The availability of affordable and compact high definition video and easy to operate underwater cameras allows citizen scientists to provide reliable observations that can be archived and reviewed by experts when desirable. [59] Accuracy of geolocation is generally lower than for terrestrial observations as the GPS features available on many digital cameras do not work underwater, and most cameras do not record depth.

See also

Footnotes

  1. The distinction between "recreational diving" and "technical diving" is not clearly and universally defined, but most major diving training agencies recognise a range of activities which they class as recreational diving and others which they class as technical diving. (see for example, PADI and DSAT, and SDI and TDI).

Related Research Articles

<span class="mw-page-title-main">Technical diving</span> Extended scope recreational diving

Technical diving is scuba diving that exceeds the agency-specified limits of recreational diving for non-professional purposes. Technical diving may expose the diver to hazards beyond those normally associated with recreational diving, and to a greater risk of serious injury or death. The risk may be reduced by appropriate skills, knowledge and experience, and by using suitable equipment and procedures. The skills may be developed through appropriate specialised training and experience. The equipment involves breathing gases other than air or standard nitrox mixtures, and multiple gas sources.

<span class="mw-page-title-main">Recreational diver training</span> Training process for people who do not dive at work

Recreational diver training is the process of developing knowledge and understanding of the basic principles, and the skills and procedures for the use of scuba equipment so that the diver is able to dive for recreational purposes with acceptable risk using the type of equipment and in similar conditions to those experienced during training.

<span class="mw-page-title-main">Professional diving</span> Underwater diving where divers are paid for their work

Professional diving is underwater diving where the divers are paid for their work. The procedures are often regulated by legislation and codes of practice as it is an inherently hazardous occupation and the diver works as a member of a team. Due to the dangerous nature of some professional diving operations, specialized equipment such as an on-site hyperbaric chamber and diver-to-surface communication system is often required by law, and the mode of diving for some applications may be regulated.

<span class="mw-page-title-main">Scuba diving</span> Swimming underwater, breathing gas carried by the diver

Scuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface air supply, and therefore has a limited but variable endurance. The name "scuba", an acronym for "Self-Contained Underwater Breathing Apparatus", was coined by Christian J. Lambertsen in a patent submitted in 1952. Scuba divers carry their own source of breathing gas, usually compressed air, affording them greater independence and movement than surface-supplied divers, and more time underwater than free divers. Although the use of compressed air is common, a gas blend with a higher oxygen content, known as enriched air or nitrox, has become popular due to the reduced nitrogen intake during long or repetitive dives. Also, breathing gas diluted with helium may be used to reduce the likelihood and effects of nitrogen narcosis during deeper dives.

<span class="mw-page-title-main">Solo diving</span> Recreational diving without a dive buddy

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.

<span class="mw-page-title-main">Underwater diving</span> Descending below the surface of the water to interact with the environment

Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well-adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done.

<span class="mw-page-title-main">Emergency ascent</span> An ascent to the surface by a diver in an emergency

An emergency ascent is an ascent to the surface by a diver in an emergency. More specifically, it refers to any of several procedures for reaching the surface in the event of an out-of-air emergency, generally while scuba diving.

<span class="mw-page-title-main">Diver training</span> Processes by which people develop the skills and knowledge to dive safely underwater

Diver training is the set of processes through which a person learns the necessary and desirable skills to safely dive underwater within the scope of the diver training standard relevant to the specific training programme. Most diver training follows procedures and schedules laid down in the associated training standard, in a formal training programme, and includes relevant foundational knowledge of the underlying theory, including some basic physics, physiology and environmental information, practical skills training in the selection and safe use of the associated equipment in the specified underwater environment, and assessment of the required skills and knowledge deemed necessary by the certification agency to allow the newly certified diver to dive within the specified range of conditions at an acceptable level of risk. Recognition of prior learning is allowed in some training standards.

<span class="mw-page-title-main">Scuba skills</span> The skills required to dive safely using SCUBA, a self-contained underwater breathing apparatus.

Scuba skills are skills required to dive safely using SCUBA, an acronym for self-contained underwater breathing apparatus, known as a scuba set. Most of these skills are relevant to both open-circuit scuba and rebreather scuba, and also to surface-supplied diving. Certain scuba skills, which are critical to divers' safety, may require more practice than standard recreational training provides.

<span class="mw-page-title-main">Autonomous diver</span> International minimum standard for entry level recreational scuba diver certification

Autonomous diver is an international minimum standard for entry level recreational scuba diver certification. It describes the minimum requirements for basic training and certification for recreational scuba divers in international standard ISO 24801-2 and the equivalent European Standard EN 14153-2. Various organizations offer training that meets the requirements of the Autonomous Diver standard. A certification which corresponds to Autonomous Diver allows for independent diving with a dive buddy in open water. Most training organizations do not recommend exceeding a depth of 18 or 20 meters at this level of certification. After completion of this certification the training can be extended to a dive leader to ISO 24801-3 or an intermediate not defined by international standards.

<span class="mw-page-title-main">Supervised diver</span> Minimum requirements for a recreational diver to dive in open water under direct supervision

Supervised diver specifies the training and certification for recreational scuba divers in international standard ISO 24801-1 and the equivalent European Standard EN 14153-1. Various diving organizations offer diving training that meets the requirements of the Supervised Diver. A diving certification which corresponds to the Supervised Diver allows for recreational diving under the direct supervision of a divemaster or recreational diving instructor in open water. Most diving organizations recommend not to exceed a diving depth of 10 to 12 metres. After the successful completion of a training equivalent to the Supervised diver, training can be extended to the Autonomous diver certification level.

Dive leader is the title of an internationally recognised recreational diving certification. The training standard describes the minimum requirements for dive leader training and certification for recreational scuba divers in international standard ISO 24801-3 and the equivalent European Standard EN 14153-3. Various organizations offer training that meets the requirements of the dive leader standard. Some agencies use the title "Dive Leader" for their equivalent certification, but several other titles are also used, "Divemaster" may be the most widespread, but "Dive Supervisor" is also used, and should not be confused with the very different status and responsibilities of a professional diving supervisor. CMAS affiliates certifications which meet the requirements of CMAS 3-star diver should meet the standard by default. The occupation of a dive leader is also known as "dive guide", and is a specialist application of a "tour guide".

<span class="mw-page-title-main">Introductory diving</span> Non-certification scuba diving experience

Introductory diving, also known as introductory scuba experience, trial diving and resort diving are dives where people without diver training or certification can experience scuba diving under the guidance of a recreational diving instructor. Introductory diving is an opportunity for interested people to find out by practical experience at a relatively low cost if they would be interested in greater involvement in scuba diving. For scuba instructors and diving schools is it an opportunity to acquire new customers. An introductory diving experience is much less time-consuming and costly than the completion of autonomous diver training, but has little lasting value, as it is an experience program only, for which no certification is issued. Introductory scuba diving experiences are intended to introduce people to recreational diving, and increase the potential client base of dive shops to include people who do not have the time or inclination to complete an entry level certification program.

Diving safety is the aspect of underwater diving operations and activities concerned with the safety of the participants. The safety of underwater diving depends on four factors: the environment, the equipment, behaviour of the individual diver and performance of the dive team. The underwater environment can impose severe physical and psychological stress on a diver, and is mostly beyond the diver's control. Equipment is used to operate underwater for anything beyond very short periods, and the reliable function of some of the equipment is critical to even short-term survival. Other equipment allows the diver to operate in relative comfort and efficiency, or to remain healthy over the longer term. The performance of the individual diver depends on learned skills, many of which are not intuitive, and the performance of the team depends on competence, communication, attention and common goals.

<span class="mw-page-title-main">History of scuba diving</span> History of diving using self-contained underwater breathing apparatus

The history of scuba diving is closely linked with the history of the equipment. By the turn of the twentieth century, two basic architectures for underwater breathing apparatus had been pioneered; open-circuit surface supplied equipment where the diver's exhaled gas is vented directly into the water, and closed-circuit breathing apparatus where the diver's carbon dioxide is filtered from the exhaled breathing gas, which is then recirculated, and more gas added to replenish the oxygen content. Closed circuit equipment was more easily adapted to scuba in the absence of reliable, portable, and economical high pressure gas storage vessels. By the mid-twentieth century, high pressure cylinders were available and two systems for scuba had emerged: open-circuit scuba where the diver's exhaled breath is vented directly into the water, and closed-circuit scuba where the carbon dioxide is removed from the diver's exhaled breath which has oxygen added and is recirculated. Oxygen rebreathers are severely depth limited due to oxygen toxicity risk, which increases with depth, and the available systems for mixed gas rebreathers were fairly bulky and designed for use with diving helmets. The first commercially practical scuba rebreather was designed and built by the diving engineer Henry Fleuss in 1878, while working for Siebe Gorman in London. His self contained breathing apparatus consisted of a rubber mask connected to a breathing bag, with an estimated 50–60% oxygen supplied from a copper tank and carbon dioxide scrubbed by passing it through a bundle of rope yarn soaked in a solution of caustic potash. During the 1930s and all through World War II, the British, Italians and Germans developed and extensively used oxygen rebreathers to equip the first frogmen. In the U.S. Major Christian J. Lambertsen invented a free-swimming oxygen rebreather. In 1952 he patented a modification of his apparatus, this time named SCUBA, an acronym for "self-contained underwater breathing apparatus," which became the generic English word for autonomous breathing equipment for diving, and later for the activity using the equipment. After World War II, military frogmen continued to use rebreathers since they do not make bubbles which would give away the presence of the divers. The high percentage of oxygen used by these early rebreather systems limited the depth at which they could be used due to the risk of convulsions caused by acute oxygen toxicity.

<span class="mw-page-title-main">Outline of underwater diving</span> Hierarchical outline list of articles related to underwater diving

The following outline is provided as an overview of and topical guide to underwater diving:

Investigation of diving accidents includes investigations into the causes of reportable incidents in professional diving and recreational diving accidents, usually when there is a fatality or litigation for gross negligence.

<span class="mw-page-title-main">Index of underwater diving</span> Alphabetical listing of underwater diving related articles

The following index is provided as an overview of and topical guide to underwater diving:

Diving procedures are standardised methods of doing things that are commonly useful while diving that are known to work effectively and acceptably safely. Due to the inherent risks of the environment and the necessity to operate the equipment correctly, both under normal conditions and during incidents where failure to respond appropriately and quickly can have fatal consequences, a set of standard procedures are used in preparation of the equipment, preparation to dive, during the dive if all goes according to plan, after the dive, and in the event of a reasonably foreseeable contingency. Standard procedures are not necessarily the only courses of action that produce a satisfactory outcome, but they are generally those procedures that experiment and experience show to work well and reliably in response to given circumstances. All formal diver training is based on the learning of standard skills and procedures, and in many cases the over-learning of the skills until the procedures can be performed without hesitation even when distracting circumstances exist. Where reasonably practicable, checklists may be used to ensure that preparatory and maintenance procedures are carried out in the correct sequence and that no steps are inadvertently omitted.

Recreational scuba certification levels are the levels of skill represented by recreational scuba certification. Each certification level is associated with a specific training standard published by the certification agency, and a training programme associated with the standard., though in some cases recognition of prior learning can apply. These levels of skill can be categorised in several ways:

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