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Scuba Diving International
Scuba Diving International (SDI) is a Scuba diving, Scuba List of diver certification organizations, training and certification agency. It is the recreational diving, recreational arm of Technical Diving International, a Technical diving, technical diver training organization. SDI is a member of World Recreational Scuba Training Council#Member Councils#United States RSTC, the United States RSTC, World Recreational Scuba Training Council#Member Councils#RSTC Canada, the RSTC Canada and World Recreational Scuba Training Council#Member Councils#RSTC Europe, the RSTC Europe. History SCUBA Diving International, launched in 1998 or 1999, is the sister organization of Technical Diving International. SDI was created by dive professionals from the technical diving field. This gives the organization the perspective of teaching recreational diving through the lens of experienced technical diving. SDI's philosophy is to improve recreational scuba diving training, enhancing older diving prac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-governmental Organization
A non-governmental organization (NGO) or non-governmental organisation (see spelling differences) is an organization that generally is formed independent from government. They are typically nonprofit entities, and many of them are active in humanitarianism or the social sciences; they can also include clubs and associations that provide services to their members and others. Surveys indicate that NGOs have a high degree of public trust, which can make them a useful proxy for the concerns of society and stakeholders. However, NGOs can also be lobby groups for corporations, such as the World Economic Forum. NGOs are distinguished from international and intergovernmental organizations (''IOs'') in that the latter are more directly involved with sovereign states and their governments. The term as it is used today was first introduced in Article 71 of the newly-formed United Nations' Charter in 1945. While there is no fixed or formal definition for what NGOs are, they ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altitude Diving
Altitude diving is underwater diving using scuba or surface supplied diving equipment where the surface is or more above sea level (for example, a mountain lake). Altitude is significant in diving because it affects the decompression requirement for a dive, so that the stop depths and decompression times used for dives at altitude are different from those used for the same dive profile at sea level. The U.S. Navy tables recommend that no alteration be made for dives at altitudes lower than and for dives between 91 and 300 meters correction is required for dives deeper than of sea water. Most recently manufactured decompression computers can automatically compensate for altitude. Measurement of depth at altitude Special consideration must be given to measurement of depth given the effect of pressure on gauges. The use of bourdon tube, diaphragm, and digital depth gauges may require adjustment for use at altitude. Capillary gauges have been shown to be a conservative method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Videography
Underwater videography is the branch of electronic underwater photography concerned with capturing underwater moving images as a recreational diving, scientific, commercial, documentary, or filmmaking activity. History In 1909, Albert Samama Chikly took the first underwater shot. In 1910, he filmed Tuna fishing in Tunisia under the patronage of Albert I, Prince of Monaco. In 1940 Hans Hass completed ''Pirsch unter Wasser'' (i.e. ''Stalking under Water'') which was published by the Universum Film AG, lasted originally only 16 minutes and was shown in theatres before the main movie, but would eventually be extended by additional filming done in the Adriatic Sea close to Dubrovnik. It premiered in Berlin in 1942. ''Sesto Continente'' directed by Folco Quilici and released in 1954, was the first full-length, full-color underwater documentary. ''The Silent World'' is noted as one of the first films to use underwater cinematography to show the ocean depths in color. Its title deri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 diving on surface supply, snorkeling, swimming, from a submersible or remotely operated underwater vehicle, or from automated cameras lowered from the surface. Underwater photography can also be categorised as an art form and a method for recording data. Successful underwater imaging is usually done with specialized equipment and techniques. However, it offers exciting and rare photographic opportunities. Animals such as fish and marine mammals are common subjects, but photographers also pursue shipwrecks, submerged cave systems, underwater "landscapes", invertebrates, seaweeds, geological features, and portraits of fellow divers. Equipment Some cameras are made for use underwater, including modern waterproof digital cameras. The first amphibious camera was the Calypso, reintroduced as the Nikonos in 1963. The Nikonos range was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Navigation
Diver navigation, termed "underwater navigation" by scuba divers, is a set of techniques—including observing natural features, the use of a compass, and surface observations—that divers use to navigate underwater. Free-divers do not spend enough time underwater for navigation to be important, and surface supplied divers are limited in the distance they can travel by the length of their umbilicals and are usually directed from the surface control point. On those occasions when they need to navigate they can use the same methods used by scuba divers. Although it is considered a basic skill, it is normally only taught to a limited degree as part of basic Open Water certification. Most North American diver training agencies only teach significant elements of underwater navigation as part of the Advanced Open Water Diver certification program. Underwater navigation is usually a core component of most, if not all, advanced recreational diver training. In the PADI Advance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Side Mount Diving
Sidemount is a scuba diving equipment configuration which has scuba sets mounted alongside the diver, below the shoulders and along the hips, instead of on the back of the diver. It originated as a configuration for advanced cave diving, as it facilitates penetration of tight sections of cave, allows easy access to cylinder valves, provides easy and reliable gas redundancy, and tanks can be easily removed when necessary. These benefits for operating in confined spaces were also recognized by divers who conducted technical wreck diving penetrations. Sidemount diving is now growing in popularity within the technical diving community for general decompression diving, and is becoming an increasingly popular specialty training for recreational diving, with several diver certification agencies offering recreational and technical level sidemount training programs. Terminology ;Sidemount diving: Sidemount diving is the practice of diving with two or more cylinders secured at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Search And Recovery
Underwater search and recovery is the process of locating and recovering underwater objects, often by divers, but also by the use of submersibles, remotely operated vehicles and electronic equipment on surface vessels. Most underwater search and recovery is done by professional divers as part of commercial marine salvage operations, military operations, emergency services, or law enforcement activities. Minor aspects of search and recovery are also considered within the scope of recreational diving. Professional search and recovery The scope of professional search and recovery includes the following applications: *Marine archeology - search for artifacts of historical interest and importance, and where applicable the recovery of such artifacts for study. *Marine salvage - search for lost material of value and recovery thereof *Environmental protection - search for environmentally undesirable material and disposal thereof *Forensic S&R - search for and recovery of material r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Night Diving
Night diving is underwater diving done during the hours of darkness. It frequently refers specifically to recreational diving which takes place in darkness. The diver can experience a different underwater environment at night, because many marine animals are nocturnal. There are additional hazards when diving in darkness, such as dive light failure. This can result in losing vertical visual references and being unable to control depth or buoyancy, being unable to read instruments such as dive computers and diving cylinder contents gauges, and potential separation from the rest of the diving group, boat, or shore cover. Even with a functioning light, these hazards are still present in night diving. Backup lights are recommended.''NOAA Diving Manual, 4th Edition'' CD-ROM prepared and distributed by the National Technical Information Service (NTIS)in partnership with NOAA and Best Publishing Company Normal requirements for night diving are a dive light, and adequate protection from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Diving
Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color. In the Solar System, ice is abundant and occurs naturally from as close to the Sun as Mercury to as far away as the Oort cloud objects. Beyond the Solar System, it occurs as interstellar ice. It is abundant on Earth's surfaceparticularly in the polar regions and above the snow lineand, as a common form of precipitation and deposition, plays a key role in Earth's water cycle and climate. It falls as snowflakes and hail or occurs as frost, icicles or ice spikes and aggregates from snow as glaciers and ice sheets. Ice exhibits at least eighteen phases ( packing geometries), depending on temperature and pressure. When water is cooled rapidly (quenching), up to three types of amorphous ice can form depending on its h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diving Equipment
Diving equipment is equipment used by underwater divers to make diving activities possible, easier, safer and/or more comfortable. This may be equipment primarily intended for this purpose, or equipment intended for other purposes which is found to be suitable for diving use. The fundamental item of diving equipment used by divers other than freedivers, is underwater breathing apparatus, such as scuba equipment, and surface-supplied diving equipment, but there are other important items of equipment that make diving safer, more convenient or more efficient. Diving equipment used by recreational scuba divers, also known as scuba gear, is mostly personal equipment carried by the diver, but professional divers, particularly when operating in the surface supplied or saturation mode, use a large amount of support equipment not carried by the diver. Equipment which is used for underwater work or other activities which is not directly related to the activity of diving, or which ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dry Suit
A dry suit or drysuit provides the wearer with environmental protection by way of thermal insulation and exclusion of water, and is worn by divers, boaters, water sports enthusiasts, and others who work or play in or near cold or contaminated water. A dry suit normally protects the whole body except the head, hands, and possibly the feet. In hazmat configurations, however, all of these are covered as well. The main difference between dry suits and wetsuits is that dry suits are designed to prevent water from entering. This generally allows better insulation, making them more suitable for use in cold water. Dry suits can be uncomfortably hot in warm or hot air, and are typically more expensive and more complex to don. For divers, they add some degree of operational complexity and hazard as the suit must be inflated and deflated with changes in depth in order to minimize "squeeze" on descent or uncontrolled rapid ascent due to excessive buoyancy, which requires additional skills ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drift Diving
Drift diving is a type of scuba diving where the diver is transported by the water movement caused by the tide, an ocean current or in a river. The choice whether to drift dive depends on the purpose of the dive, and whether there is an option. At some sites there is almost always a current running, and at others the strength and direction of water movement may vary with the tide, or other driving forces, like wind or recent rainfall. At some sites there may be considerable variation in visibility and underwater life activity based on the speed and direction of flow. 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. Often drift diving is performed more for the experience of underwater "flight" and less for interactions with underwater life, which, given the speed at which most divers move, are reduced. Procedures Drift dives can be done from the shore, but this r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
