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Recreational Diving

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Recreational diving



 
 
Recreational diving or sport diving is a type of diving
Underwater diving

Underwater diving is the practice of going underwater Scuba diving or without breathing apparatus.Recreational diving is a popular activity ....
 that uses SCUBA equipment
Scuba set

A scuba set is an independent breathing set that provides a scuba diver with the breathing gas necessary to breathe underwater during scuba diving....
 for the purpose of leisure and enjoyment. In some diving circles, the term "recreational diving" is used in contradistinction to "technical diving
Technical diving

Technical diving is a form of scuba diving that exceeds the scope of recreational diving . Technical divers require advanced training, extensive experience, specialized equipment and often breathe breathing gases other than air or standard nitrox....
", a more demanding aspect of the sport which requires greater levels of training, experience and equipment.The distinction (if a distinction exists) between "recreational diving" and "technical diving" is a source of some debate within the diving community, but most major diving training agencies
List of diver training organizations

This page lists Scuba diving diver training organizations....
 recognise and broad distinction (see for example, PADI
Professional Association of Diving Instructors

The Professional Association of Diving Instructors is the world's largest recreational diving membership and List of diver training organizations founded in 1966 by John Cronin and Ralph Erickson....
 and DSAT
Diving Science and Technology

Diving Science and Technology is a corporate affiliate of Professional Association of Diving Instructors and the developer of the Recreational Dive Planner....
, and SDI
SCUBA Diving International

Scuba Diving International is a Scuba diving List of diver training organizations. It is the recreational diving arm of Technical Diving International, the world?s largest Technical_diving training organization....
 and TDI
Technical Diving International

Technical Diving International is the largest Technical_diving Diver training in the world. TDI specializes in more advanced Scuba diving techniques, such as diving with Rebreather and mixed Breathing_gas, such as Heliox....
).


eational scuba diving grew out of related activities such as snorkel
Snorkeling

Snorkeling is the practice of swimming on or through a body of water while equipped with a diving mask, a shaped tube called a snorkel, and usually swimfins....
ling and underwater hunting
Spearfishing

Spearfishing is a form of fishing that has been popular throughout the world for centuries. Early civilizations are familiar with the custom of spearing fish out of rivers and streams using sharpened sticks as a means of catching food....
.






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Encyclopedia


Recreational diving or sport diving is a type of diving
Underwater diving

Underwater diving is the practice of going underwater Scuba diving or without breathing apparatus.Recreational diving is a popular activity ....
 that uses SCUBA equipment
Scuba set

A scuba set is an independent breathing set that provides a scuba diver with the breathing gas necessary to breathe underwater during scuba diving....
 for the purpose of leisure and enjoyment. In some diving circles, the term "recreational diving" is used in contradistinction to "technical diving
Technical diving

Technical diving is a form of scuba diving that exceeds the scope of recreational diving . Technical divers require advanced training, extensive experience, specialized equipment and often breathe breathing gases other than air or standard nitrox....
", a more demanding aspect of the sport which requires greater levels of training, experience and equipment.The distinction (if a distinction exists) between "recreational diving" and "technical diving" is a source of some debate within the diving community, but most major diving training agencies
List of diver training organizations

This page lists Scuba diving diver training organizations....
 recognise and broad distinction (see for example, PADI
Professional Association of Diving Instructors

The Professional Association of Diving Instructors is the world's largest recreational diving membership and List of diver training organizations founded in 1966 by John Cronin and Ralph Erickson....
 and DSAT
Diving Science and Technology

Diving Science and Technology is a corporate affiliate of Professional Association of Diving Instructors and the developer of the Recreational Dive Planner....
, and SDI
SCUBA Diving International

Scuba Diving International is a Scuba diving List of diver training organizations. It is the recreational diving arm of Technical Diving International, the world?s largest Technical_diving training organization....
 and TDI
Technical Diving International

Technical Diving International is the largest Technical_diving Diver training in the world. TDI specializes in more advanced Scuba diving techniques, such as diving with Rebreather and mixed Breathing_gas, such as Heliox....
).


History

Recreational scuba diving grew out of related activities such as snorkel
Snorkeling

Snorkeling is the practice of swimming on or through a body of water while equipped with a diving mask, a shaped tube called a snorkel, and usually swimfins....
ling and underwater hunting
Spearfishing

Spearfishing is a form of fishing that has been popular throughout the world for centuries. Early civilizations are familiar with the custom of spearing fish out of rivers and streams using sharpened sticks as a means of catching food....
. For a long time, recreational underwater
Underwater

Underwater is a term describing the realm below the surface of water where the water exists in a natural feature such as an ocean, sea, lake, pond, or river....
 excursions were limited by the amount of breath that could be held. However, the invention of the aqualung
Aqua-lung

Aqualung was the original name for the first open-circuit Scuba sets, developed by Emile Gagnan and Jacques-Yves Cousteau in 1943. It consists of a high pressure diving cylinder and a diving regulator that supplies the diver with breathing gas at ambient pressure, via a demand valve....
 in 1943 by Jacques-Yves Cousteau
Jacques-Yves Cousteau

Jacques-Yves Cousteau was a France naval officer, exploration, ecologist, filmmaker, innovator, scientist, photographer, author and researcher who studied the sea and all forms of life in water....
 and its development over subsequent years led to a revolution in recreational diving. 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.

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, modern diving regulator
Diving regulator

A diving regulator is a pressure regulator used in a scuba set that supplies the diver with breathing gas at ambient pressure from one or more diving cylinders....
s, wet or dry suit
Dry suit

A dry suit or drysuit provides thermal insulation or passive thermal protection to the wearer while immersed in water, and is worn by underwater diving, boating, Water sport, and others who work or play in or near cold water....
s, and dive computer
Dive computer

A dive computer or decompression meter is a device used by a Scuba diving to measure the time and depth of a dive so that a safe ascent rate can be calculated and displayed so that the diver can avoid decompression sickness....
s, 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 created in France to train the owners of the Jacques Yves Cousteau and Emile Gagnan designed double hose scuba. The first school to teach the modern 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. However, neither of these schools were international in nature.

There were no training courses, in the modern sense, available to civilians who bought the first scuba equipment. Some of the first training started in 1953 Trevor Hampton created the first British diving school, the British Underwater Centre and 1954 when Los Angeles County created an Underwater Instructor Certification Course. Early instruction increased in the form of amateur teaching within a club environment, as exemplified by organizations such as the Scottish Sub-Aqua Club and the British Sub Aqua Club
British Sub Aqua Club

The British Sub-Aqua Club or BSAC has been recognised since 1954 by the Sports Council as the governing body of recreational diving in the United Kingdom....
 from 1953, Los Angeles County from 1954 and the YMCA from 1959.

Professional instruction started in 1959 when the non-profit National Association of Underwater Instructors was formed , which later effectively was split, to form the for-profit Professional Association of Diving Instructors
Padi

Padi or PADI can refer to:* Professional Association of Diving Instructors, diver training organization* Paddy field * Padi, Chennai, satellite township of Chennai, India...
 in 1966. NASDS the National Association of Scuba Diving Schools started with their Dive Center based Training programs in 1962 followed by Scuba Schools International
SSI

SSI has many meanings, depending on the topic:...
 in 1970. PDIC professional diving instructors college was formed in 1965, later changing its name to PDIC professional diving instructors Corporation in 1984, providing training in a retail environment.

Diving today


Further developments in technology have reduced the cost of training and diving. Scuba-diving has become a popular leisure activity, and many diving locations have some form of dive shop presence that can offer air fills, equipment and training.

In tropical and sub-tropical parts of the world, there is a large market in 'holiday divers'; people who train and dive while on holiday, but rarely dive close to home.

Technical diving
Technical diving

Technical diving is a form of scuba diving that exceeds the scope of recreational diving . Technical divers require advanced training, extensive experience, specialized equipment and often breathe breathing gases other than air or standard nitrox....
 and use of rebreather
Rebreather

A rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where humans cannot safely breathe from the atmosphere....
s are increasing, particularly in areas of the world where deeper wreck diving
Wreck diving

Wreck diving is a type of recreational diving where shipwrecks are explored. Although most wreck dive sites are at shipwrecks, there is an increasing trend to Sinking ships for wreck diving sites....
 is the main underwater attraction. Generally, recreational diving depths are limited to a maximum of between 30 and 40 meters (100 and 130 feet), beyond which a variety of safety issues make it unsafe to dive using recreation diving equipment and practices, and specialized training and equipment for technical diving
Technical diving

Technical diving is a form of scuba diving that exceeds the scope of recreational diving . Technical divers require advanced training, extensive experience, specialized equipment and often breathe breathing gases other than air or standard nitrox....
 are needed.

Standard equipment

  • Diving or Scuba mask
    Diving mask

    A diving mask is an item of diving equipment that allows scuba diving, free-diving, and snorkeling to see clearly underwater. When the human eye is in direct contact with water as opposed to air, its normal environment, light entering the eye is refracted by a different angle and the eye is unable to Focus the light....
     and Snorkel
  • Swimfin
    Swimfin

    Swimfins, swim fins, shinfin fins or flippers are worn on the foot or leg and made from finlike rubber or plastic, to aid movement through the water in Water sport activities such as swimming, bodyboarding, bodysurfing, kneeboarding , riverboarding, and various types of underwater diving....
    s or Scuba fins
  • Wet or Dry suit
    Dry suit

    A dry suit or drysuit provides thermal insulation or passive thermal protection to the wearer while immersed in water, and is worn by underwater diving, boating, Water sport, and others who work or play in or near cold water....
  • Buoyancy compensator or buoyancy control device (BCD)
  • Diving weighting system
    Diving weighting system

    Divers wear weighting systems, weight belts or weights, generally made of lead, to counteract the buoyancy of other diving equipment, such as diving suits and aluminium diving cylinders....
     or weight belt
  • Diving cylinder
    Diving cylinder

    A diving cylinder, scuba tank or diving tank is used to store and transport high pressure breathing gas as a component of SCUBA . It provides gas to the Scuba diving through the demand valve of a diving regulator....
     or Scuba tank
  • Diving regulator
    Diving regulator

    A diving regulator is a pressure regulator used in a scuba set that supplies the diver with breathing gas at ambient pressure from one or more diving cylinders....
  • Contents gauge
    Diving regulator

    A diving regulator is a pressure regulator used in a scuba set that supplies the diver with breathing gas at ambient pressure from one or more diving cylinders....
     or submersible pressure gauge (SPG)


Issues

There are several recreational diving issues that are currently topics of discussion within the diving community. They include:

Training levels


There is a certain amount of disquiet over the level of training and experience necessary to qualify as a diver. Under most entry-level programs (SDI
SCUBA Diving International

Scuba Diving International is a Scuba diving List of diver training organizations. It is the recreational diving arm of Technical Diving International, the world?s largest Technical_diving training organization....
, PADI
Padi

Padi or PADI can refer to:* Professional Association of Diving Instructors, diver training organization* Paddy field * Padi, Chennai, satellite township of Chennai, India...
, BSAC,SSAC, NAUI, SSI
Scuba Schools International

Scuba Schools International or SSI is an organization that teaches the skills involved in scuba diving and supports Dive Businesses and Dive Resorts....
, PDIC
PDIC

PDIC may refer to:*Philippine Deposit Insurance Corporation*Professional Diving Instructors Corporation...
 and CMAS) divers can complete a certification with as few as four 'open-water' dives. Such a qualification allows a diver to rent equipment, request air fills, and dive without any higher supervision, provided they do so with a buddy. Critics claim that four dives is too few to prepare new divers for such a level of responsibility, and that either the total should be raised or the certification qualified. Certification agencies normally answer that they advise their students to dive within the envelope of their experience and training, and to seek to extend both through properly supervised (and frequently revenue-producing) programs, but in the 1980s, several of the Agencies with DEMA did collaborate to author ANSI Standard Z86.3 (1989), Minimum Course Content For Safe Scuba Diving which now serves to limit their potential liability from lawsuits on training adequacy issues by defining their training as the definition of Accepted Industry Practices.

Regular vs. leisure


Some divers see a split beginning to emerge in recreational diving between regular recreational divers, who often dive in their home communities, and leisure divers, characterized as those who dive occasionally, normally when abroad on holiday and in more benign conditions. It is sometimes observed that there is a tension between the two, and that leisure divers are often inexperienced, either under-trained or over-qualified, and sustain only a minimal empathy with the underwater world. The call is usually not that these divers be restrained from diving, but that they be encouraged to dive more regularly in their home communities so as to gain experience and support their local diving scene. However, as recreational diving has a very low accident and death rate, it is a commonly claimed view that current training requirements are adequate.

Specialties


There are many diving activities which need further training than that provided by the initial courses:

  • Altitude diving
    Altitude diving

    Altitude diving is scuba diving where the surface is 300 meters or more above sea level . The U.S. Navy tables recommend that no alteration be made for dives at altitudes lower than 91 meters and dives between 91 meters and 300 meters correction is required for dives over 44 meters sea water ....
  • Cave diving
    Cave diving

    Cave diving is a type of technical diving in which specialized Scuba set is used to enable the exploration of natural or artificial caves which are at least partially filled with water....
  • Deep diving
    Deep diving

    The meaning of the term deep diving is a form of technical diving. It is defined by the level of the diver's diver training, diving equipment, breathing gas, and surface support:...
  • Drift diving
    Drift diving

    Drift diving is a type of recreational diving where the diver is transported by the currents caused by the tide or in a river.The current gives the diver the impression of flying and allows the diver to cover long distances underwater, possibly seeing more habitats and formations than usual....
  • Free-diving
    Free-diving

    Freediving is any of various aquatic activities that share the practice of breath-hold underwater diving. Examples include breathhold spear fishing, freedive photography, apnea competitions and, to a degree, snorkeling....
     also called skin diving
  • Ice diving
    Ice diving

    Ice diving is a type of penetration diving where the dive takes place under ice. Because diving under ice places the diver in an overhead environment typically with only a single entry/exit point, it is considered an advanced type of diving requiring special training ....
  • Identifying and surveying sea life and freshwater life: see marine biology
    Marine biology

    Marine biology is the scientific study of living organisms in the ocean or other Marine or brackish bodies of water.Given that in biology many scientific classification, families and Genera have some species that live in the sea and others that live on land, marine biology classifies species based on the environment rather than on taxon...
  • Maritime archeology or Underwater archeology
  • Night diving
    Night diving

    Night diving is a type of recreational diving which takes place in darkness. The diver may see more and has a different underwater experience at night because many marine animals are nocturnal and the diver is forced to concentrate on smaller, nearby objects....
  • Snorkeling
    Snorkeling

    Snorkeling is the practice of swimming on or through a body of water while equipped with a diving mask, a shaped tube called a snorkel, and usually swimfins....
  • Underwater navigation
    Underwater navigation

    Underwater navigation is the common reference term for navigation techniques learned by Scuba diving in order to accurately navigate in an underwater environment....
  • Underwater photography
    Underwater photography

    Underwater photography is the process of taking photographs while under water. It is usually done while scuba diving, but can be done while snorkeling or swimming....
  • Underwater search and recovery
    Underwater search and recovery

    Underwater search and recovery is the process of locating and recovering underwater objects by Scuba diving. Although most underwater search and recovery is done by professional diving as part of professional marine salvage operations, search and recovery diving is also frequently undertaken as part of recreational diving, and most List of d...
  • Underwater videography
    Underwater videography

    Underwater Videography is the branch of underwater photography concerned with capturing underwater moving images either as a recreational diving or commercial documentary film or film making activity....
  • Wreck diving
    Wreck diving

    Wreck diving is a type of recreational diving where shipwrecks are explored. Although most wreck dive sites are at shipwrecks, there is an increasing trend to Sinking ships for wreck diving sites....
  • Nitrox diving


Many diver training
Diver training

Diver training is the process of developing skills and building experience in the use of diving equipment and techniques so that the diver is able to diving activities safely and have fun....
 agencies such as ACUC, BSAC
BSAC

BSAC can stand for:*Berkeley Sensor and Actuator Center*Bit Sliced Arithmetic Coding, audio coding from MPEG-4 Part 3*British South Africa Company...
, CMAS, IANTD, NAUI, PADI
Padi

Padi or PADI can refer to:* Professional Association of Diving Instructors, diver training organization* Paddy field * Padi, Chennai, satellite township of Chennai, India...
, PDIC
PDIC

PDIC may refer to:*Philippine Deposit Insurance Corporation*Professional Diving Instructors Corporation...
, SDI
SCUBA Diving International

Scuba Diving International is a Scuba diving List of diver training organizations. It is the recreational diving arm of Technical Diving International, the world?s largest Technical_diving training organization....
, SSI
Scuba Schools International

Scuba Schools International or SSI is an organization that teaches the skills involved in scuba diving and supports Dive Businesses and Dive Resorts....
 and YMCA offer training in these areas, as well as opportunities to move into professional instruction, technical diving
Technical diving

Technical diving is a form of scuba diving that exceeds the scope of recreational diving . Technical divers require advanced training, extensive experience, specialized equipment and often breathe breathing gases other than air or standard nitrox....
, commercial diving
Commercial Diving

Professional Diving is a type of diving activities where the divers are paid for their work. There are several branches of professional diving, the most well known of which is probably commercial diving....
 and others.

Bodies of water for diving


Most bodies of water can be used as dive sites:

  • Seas
    Seas

    SEAS may mean:*The plural of "sea"*Shipboard Environmental Acquisition System: a program developed by National Oceanic and Atmospheric Administration to provide accurate meteorological and oceanographic data in real time from ships at sea through the use of satellite data transmission techniques....
     and Oceans - these consist of salt water and a huge variety of flora and fauna.
  • Lakes - small lakes are often used for diver training
    Diver training

    Diver training is the process of developing skills and building experience in the use of diving equipment and techniques so that the diver is able to diving activities safely and have fun....
    . Large lakes have many features of seas including wrecks and a variety of marine life
    Marine biology

    Marine biology is the scientific study of living organisms in the ocean or other Marine or brackish bodies of water.Given that in biology many scientific classification, families and Genera have some species that live in the sea and others that live on land, marine biology classifies species based on the environment rather than on taxon...
    . Man-made lakes, such as clay pit
    Clay pit

    A clay pit is a quarry or Mining for the extraction of clay, which is generally used for manufacturing pottery, bricks or Portland cement.The brick factory is often located alongside the clay pit to reduce the transport costs of the raw material....
    s and gravel pit
    Gravel pit

    File:Aerial fg103 DSC 1469 Kiesgrube bei Geinsheim.JPGGravel pit is the term for an open-pit mining working for extraction of gravel . Gravel pits normally lie in river valleys where the water table is high, so they fill naturally with water to form ponds or lakes....
    s, often have lower visibility. Some lakes are high in altitude, and the requre special considerations for diving. See Altitude diving
    Altitude diving

    Altitude diving is scuba diving where the surface is 300 meters or more above sea level . The U.S. Navy tables recommend that no alteration be made for dives at altitudes lower than 91 meters and dives between 91 meters and 300 meters correction is required for dives over 44 meters sea water ....
  • Caves - these are more adventurous and dangerous than normal diving. See cave diving
    Cave diving

    Cave diving is a type of technical diving in which specialized Scuba set is used to enable the exploration of natural or artificial caves which are at least partially filled with water....
    .
  • Rivers - are often shallow, murky and have strong currents.
  • Quarries
    Scuba diving quarry

    File:Wazee 007.jpgScuba diving quarries are depleted or abandoned Quarry that have been allowed to fill with ground water, and rededicated to the purpose of scuba diving....
     - abandoned rock quarries are popular in inland areas for diver training as well as recreational diving. Rock quarries also have reasonable underwater visibility - there is often little mud or sand to create mid-water particles that cause low visibility. As they are not "wild" and usually privately owned, quarries often contain objects intentionally placed for divers to explore, such as sunken boats, automobiles, aircraft, and even structures like grain silos and gravel chutes.


Dive site features


Many types of underwater
Underwater

Underwater is a term describing the realm below the surface of water where the water exists in a natural feature such as an ocean, sea, lake, pond, or river....
 feature make an interesting dive site, for example:

Coral Reef Locations
  • Wildlife at the site. Popular examples are coral
    Coral

    Corals are marine organisms from the class Anthozoa and exist as small sea anemone?like polyps, typically in colonies of many identical individuals....
    , sponge
    Sea sponge

    The sponges or poriferans are animals of the phylum Porifera . Their bodies consist of an outer thin layer of cells, the pinacoderm and an inner mass of cells and skeletal elements, the choanoderm....
    s, fish
    Fish

    A fish is any marine biology vertebrate animal that is typically ectothermic , covered with scale , and equipped with two sets of paired fins and several unpaired fins....
    , sting rays, molluscs, cetacea
    Cetacea

    The order Cetacea includes whales, dolphins, and porpoises. Cetus is Latin and is used in biological names to mean "whale"; its original meaning, "large sea animal", was more general....
    ns, seal
    Pinniped

    Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semi-aquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae ....
    s, shark
    Shark

    Sharks are a type of fish with a full Cartilage skeleton and a highly Streamlines, streaklines and pathlinesd body. They respire with the use of five to seven gill slits....
    s and crustacean
    Crustacean

    Crustaceans are a large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles....
    s.


  • The Topography of the site. Coral reef
    Coral reef

    Coral reefs are aragonite structures produced by living organisms. In most reefs the predominant organisms are colonial cnidarian that secrete an exoskeleton of calcium carbonate....
    s, drop offs (underwater cliff
    Cliff

    In geography and geology, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are formed as erosion landforms due to the processes of erosion and weathering that produce them....
    s), rock reef
    Reef

    In nautical terminology, a reef is a Rock , bar , or other feature lying beneath the surface of the water .Many reefs result from abiotic processes?deposition of sand, wave erosion planning down rock outcrops, and other natural processes?but the best-known reefs are the coral reefs of tropical waters developed through biotic processes do...
    s, gullies and cave
    Cave

    A cave is a natural underground void large enough for a human to enter. Some people suggest that the term cave should only apply to cavities that have some part that does not receive daylight; however, in popular usage, the term includes smaller spaces like sea caves, rock shelters, and grottos....
    s can be spectacular. Deep dive sites mean divers must reduce the time they spend because more gas is breathed at depth and decompression sickness
    Decompression sickness

    'Decompression sickness' , 'the diver?s disease', 'the bends', 'caisson disease' is the name given to a variety of symptoms suffered by a person exposed to a decrease in the pressure around the body....
     risks increase. Shallow regions can be investigated by snorkeling
    Snorkeling

    Snorkeling is the practice of swimming on or through a body of water while equipped with a diving mask, a shaped tube called a snorkel, and usually swimfins....
    .


  • Historical or cultural items at the site. Ship wrecks and sunken aircraft
    Aircraft

    An aircraft is a vehicle which is able to flight by being supported by the air, or in general, the atmosphere, of a planet. Examples include balloons, airplanes and helicopters....
    , apart from their historical value, form artificial habitats
    Habitat (ecology)

    A habitat is an ecological or Natural_environment area that is inhabited by a particular animal or plant species. It is the natural environment in which an organism lives, or the physical environment that surrounds a species population....
     for marine fauna making them attractive dive sites.


  • Underwater visibility
    Visibility

    In meteorology, visibility is a measure of the distance at which an object or light can be clearly discerned. It is reported within surface weather observations and METAR code either in meters or statute miles, depending upon the country....
     varies widely. Poor visibility is caused by particles in the water, such as mud
    MUD

    In Online game, a MUD , pronounced /m?d/, is a multi-user real-time virtual world described entirely in text. It combines elements of role-playing games, hack and slash, interactive fiction, and online chat....
    , sand
    Sand

    Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.As the term is used by geologists, sand particles range in diameter from 0.0625 to 2 millimeters....
     and sewage
    Sewage

    Sewage is the mainly liquid waste containing some solids produced by humans which typically consists of washing water, feces, urine, laundry waste and other material which goes down Plumbing fixture from households and industry....
    . Dive sites that are close to sources of these particles, such as human settlements and river estuaries, are more prone to poor visibility. Currents can stir up the particles. Diving close to the sediments on the seabed can result in the particles being kicked up by the divers fins.


  • Temperature. Warm water diving is comfortable and convenient. Although cold water is uncomfortable and can cause hypothermia
    Hypothermia

    Hypothermia is a condition in which an organism's temperature drops below that required for normal metabolism and bodily functions. In warm-blooded animals, core body temperature is maintained near a constant level through biologic homeostasis....
     it can be interesting because different species of underwater life thrive in cold conditions. Cold water means divers tend to prefer Dry suits with inner thermal clothing which offer greater thermal protection although require training and experience to use properly.


  • Currents. Tidal current
    Tide

    Tides are the rising of Earth's ocean surface caused by the tidal forces of the Moon and the Sun acting on the oceans. Tides cause changes in the depth of the marine and estuary water bodies and produce oscillating currents known as tidal streams, making prediction of tides important for coastal navigation ....
    s can transport nutrient
    Nutrient

    A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment....
    s to underwater wildlife increasing the variety and density of that life at the site. Currents can also be dangerous to divers as they can result in the diver being swept away from his or her surface support. Tidal currents that meet solid underwater vertical surfaces can cause strong up or down currents that are dangerous because they may cause the diver to lose buoyancy
    Buoyancy

    In physics, buoyancy is the upward force that keeps things afloat. The net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body....
     control risking barotrauma
    Barotrauma

    Barotrauma is physical damage to body tissues caused by a difference in pressure between an air space inside or beside the body and the surrounding gas or liquid....
    .


Footnotes



External links

  • - The official magazine of the PADI Diving Society
  • The New York Times (April 8, 2007)
  • - Dive site atlas from the British Sub Aqua Club
    British Sub Aqua Club

    The British Sub-Aqua Club or BSAC has been recognised since 1954 by the Sports Council as the governing body of recreational diving in the United Kingdom....
  • - Dive locations in Asia and dive supply.
  • - Global dive site location atlas created with contributions from the diving community
  • - Global GPS based dive site and services location that can be viewed in Google Earth
    Google Earth

    Google Earth is a virtual globe, map and geographic information program that was originally called Earth Viewer, and was created by Keyhole, Inc, a company acquired by Google in 2004....