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Technical Diver
Technical diving (also referred to as tec diving or tech 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 often involves breathing gases other than air or standard nitrox mixtures, and multiple gas sources. The popularisation of the term ''technical diving'' has been credited to Michael Menduno, who was editor of the (now defunct) diving magazine ''aquaCorps Journal'', but the concept and term, ''technical diving'', go back at least as far as 1977,In his 1989 book, ''Advanced Wreck Diving'', author and leading technical diver, Gary Gentile, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technical Diving International
Technical Diving International (TDI) claims to be the largest technical diving certification agency in the world, and one of the first agencies to offer mixed gas and rebreather training. TDI specializes in more advanced Scuba diving techniques, particularly diving with rebreathers and use of breathing gases such as trimix and heliox. TDI provides courses and certification for divers and for instructors. TDI history TDI was founded in 1994 by Bret Gilliam, David Sipperly and Mitch Skaggs after a split away from International Association of Nitrox and Technical Divers (IANTD) in 1993. The agency aimed to provide training materials and education for specialized diving situations. Some courses offered by TDI include open circuit courses such as diving with Nitrox as well as Rebreather courses. They also provide training for overhead environments like caves and wrecks, mixed gas training and were one of the first diving agencies to create a comprehensive insurance plan for t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimix (breathing Gas)
Trimix is a breathing gas consisting of oxygen, helium and nitrogen and is used in deep commercial diving, during the deep phase of dives carried out using technical diving techniques, and in advanced recreational diving. The helium is included as a substitute for some of the nitrogen, to reduce the narcotic effect of the breathing gas at depth. With a mixture of three gases it is possible to create mixes suitable for different depths or purposes by adjusting the proportions of each gas. Oxygen content can be optimised for the depth to limit the risk of toxicity, and the inert component balanced between nitrogen (which is cheap but narcotic) and helium (which is not narcotic and reduces work of breathing, but is more expensive and increases heat loss). The mixture of helium and oxygen with a 0% nitrogen content is generally known as heliox. This is frequently used as a breathing gas in deep commercial diving operations, where it is often recycled to save the expensive helium c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trevor Jackson Returns From SS Kyogle
Trevor ( Trefor in the Welsh language) is a common given name or surname of Welsh origin. It is an habitational name, deriving from the Welsh ''tre(f)'', meaning "homestead", or "settlement" and ''fawr'', meaning "large, big". The Cornish language equivalent is Trevorrow and is most associated with Ludgvan. Trevor is also a reduced Anglicized form of the Gaelic ''Ó Treabhair'' (descendant of Treabhar), which may derive from the original Welsh name. As a surname People *Claire Trevor (1910–2000), American actress *Hugh Trevor (1903–1933), American actor *John Trevor (other), various people *William Trevor (1928–2016), Irish writer * William Spottiswoode Trevor (1831–1907), recipient of the Victoria Cross Fictional characters *Steve Trevor, in the DC Comics, 1970s television series and 2017 film ''Wonder Woman'' As a given name People *Trevor Ariza (born 1985), American basketball player *Trevor Bailey, English cricketer *Trevor Bauer, American baseball player ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxia (medical)
Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Hypoxia may be classified as either '' generalized'', affecting the whole body, or ''local'', affecting a region of the body. Although hypoxia is often a pathological condition, variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise.. Hypoxia differs from hypoxemia and anoxemia, in that hypoxia refers to a state in which oxygen present in a tissue or the whole body is insufficient, whereas hypoxemia and anoxemia refer specifically to states that have low or no oxygen in the blood. Hypoxia in which there is complete absence of oxygen supply is referred to as anoxia. Hypoxia can be due to external causes, when the breathing gas is hypoxic, or internal causes, such as reduced effectiveness of gas transfer in the lungs, reduced capacity of the blood to carry oxygen, compromised general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliox
Heliox is a breathing gas mixture of helium (He) and oxygen (O2). It is used as a medical treatment for patients with difficulty breathing because mixture generates less resistance than atmospheric air when passing through the airways of the lungs, and thus requires less effort by a patient to breathe in and out of the lungs. It is also used as a breathing gas diluent for deep ambient pressure diving as it is not narcotic at high pressure, and for its low work of breathing. Heliox has been used medically since the 1930s, and although the medical community adopted it initially to alleviate symptoms of upper airway obstruction, its range of medical uses has since expanded greatly, mostly because of the low density of the gas. Heliox is also used in saturation diving and sometimes during the deep phase of technical dives. Medical uses In medicine heliox may refer to a mixture of 21% O2 (the same as air) and 79% He, although other combinations are available (70/30 and 60/40). Hel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrox
Nitrox refers to any gas mixture composed (excepting trace gases) of nitrogen and oxygen. This includes atmospheric air, which is approximately 78% nitrogen, 21% oxygen, and 1% other gases, primarily argon. In the usual application, underwater diving, nitrox is normally distinguished from air and handled differently. The most common use of nitrox mixtures containing oxygen in higher proportions than atmospheric air is in scuba diving, where the reduced partial pressure of nitrogen is advantageous in reducing nitrogen uptake in the body's tissues, thereby extending the practicable underwater dive time by reducing the decompression requirement, or reducing the risk of decompression sickness (also known as ''the bends''). Nitrox is used to a lesser extent in surface-supplied diving, as these advantages are reduced by the more complex logistical requirements for nitrox compared to the use of simple low-pressure compressors for breathing gas supply. Nitrox can also be used in hyper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Blending
Gas blending is the process of mixing gases for a specific purpose where the composition of the resulting mixture is specified and controlled. A wide range of applications include scientific and industrial processes, food production and storage and breathing gases. Gas mixtures are usually specified in terms of molar gas fraction (which is closely approximated by volumetric gas fraction for many permanent gases): by percentage, parts per thousand or parts per million. Volumetric gas fraction converts trivially to partial pressure ratio, following Dalton's law of partial pressures. Partial pressure blending at constant temperature is computationally simple, and pressure measurement is relatively inexpensive, but maintaining constant temperature during pressure changes requires significant delays for temperature equalization. Blending by mass fraction is unaffected by temperature variation during the process, but requires accurate measurement of mass or weight, and calculation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decompression Stop
The practice of decompression by divers comprises the planning and monitoring of the profile indicated by the algorithms or tables of the chosen decompression model, to allow asymptomatic and harmless release of excess inert gases dissolved in the tissues as a result of breathing at ambient pressures greater than surface atmospheric pressure, the equipment available and appropriate to the circumstances of the dive, and the procedures authorized for the equipment and profile to be used. There is a large range of options in all of these aspects. Decompression may be continuous or staged, where the ascent is interrupted by stops at regular depth intervals, but the entire ascent is part of the decompression, and ascent rate can be critical to harmless elimination of inert gas. What is commonly known as no-decompression diving, or more accurately no-stop decompression, relies on limiting ascent rate for avoidance of excessive bubble formation. Staged decompression may include deep st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Diving
Deep diving is underwater diving to a depth beyond the norm accepted by the associated community. In some cases this is a prescribed limit established by an authority, while in others it is associated with a level of certification or training, and it may vary depending on whether the diving is recreational, technical or commercial. Nitrogen narcosis becomes a hazard below and hypoxic breathing gas is required below to lessen the risk of oxygen toxicity. For some recreational diving agencies, "Deep diving", or "Deep diver" may be a certification awarded to divers that have been trained to dive to a specified depth range, generally deeper than . However, the Professional Association of Diving Instructors (PADI) defines anything from as a "deep dive" in the context of recreational diving (other diving organisations vary), and considers ''deep diving'' a form of technical diving. In technical diving, a depth below about where hypoxic breathing gas becomes necessary to avoid oxyge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sub-Aqua Association
The Sub-Aqua Association or SAA is a diver training organization for scubadivers in the United Kingdom. The SAA and other UK-based diving groups have traditionally used a club-based system with unpaid instructors, while other training agencies organise most of their training programs through professional instructors and dive shops. The other major club-based diving organizations in the UK are the British Sub-Aqua Club (BSAC) and the Scottish Sub Aqua Club, and the principal non-club-based organisation is PADI. History The Sub-Aqua Association was created in 1976 to represent diving clubs outside of the BSAC branch structure. Its training structure is based on the BSAC levels and offers a full range of diving qualifications. The association is made up of independent clubs, while the BSAC is a single club with many branches. Training Sub-Aqua Association member clubs maintain their independence and individual clubs organize diving programs and instruction according to the nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bühlmann Tables , random effects model used in credibility theory in actuarial science to determine the ins ...
Bühlmann is a surname. Notable people with the surname include: * Albert A. Bühlmann (1923–1994), Swiss physician at the Laboratory of Hyperbaric Physiology at the University Hospital, Zürich, Switzerland *Claudia Bühlmann, Swiss bobsledder who competed in the mid-1990s *Gabriele Bühlmann (born 1964), Swiss rifle shooter who competed at five Olympic Games from 1988 to 2004 *Paul Bühlmann (1927–2000), Swiss actor *Peter Bühlmann (born 1965), Swiss mathematician and statistician See also *Bühlmann decompression algorithm, mathematical model of the way that inert gases enter and leave the body as pressure changes *Bühlmann model In credibility theory, a branch of study in actuarial science, the Bühlmann model is a random effects model (or "variance components model" or hierarchical linear model) used to determine the appropriate premium for a group of insurance contract ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
