Index of underwater diving: A–C

Last updated February 18, 2025

The following index is provided as an overview of and topical guide to underwater diving: Links to articles and redirects to sections of articles which provide information on each topic are listed with a short description of the topic. When there is more than one article with information on a topic, the most relevant is usually listed, and it may be cross-linked to further information from the linked page or section.

A human activity – intentional, purposive, conscious and subjectively meaningful sequence of actions. Underwater diving is practiced as part of an occupation, or for recreation, where the practitioner submerges below the surface of the water or other liquid for a period which may range between seconds to order of a day at a time, either exposed to the ambient pressure or isolated by a pressure resistant suit, to interact with the underwater environment for pleasure, competitive sport, or as a means to reach a work site for profit or in the pursuit of knowledge, and may use no equipment at all, or a wide range of equipment which may include breathing apparatus, environmental protective clothing, aids to vision, communication, propulsion, maneuverability, buoyancy control and safety equipment, and tools for the task at hand.

There are seven sub-indexes, listed here. The tables of content should link between them automatically:

0–9

Contents: Top	0–9	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z

14th CMAS Underwater Photography World Championship – 2013 photography competition held in Cuba
1973 Mount Gambier cave diving accident – Scuba cave diving incident in South Australia
1982 invasion of the Falkland Islands – Argentine invasion of the Falklands
1992 cageless shark-diving expedition – First recorded cageless dive with great white sharks
2011 Finswimming World Championships – 2011 swimming competition held in Hungary
2013 Finswimming World Championships – International competition in Kazan, Russia
2016 Finswimming World Championships – International competition in Volos, Greece
2018 Finswimming World Championships – International competition in Belgrade, Serbia
35-ton deep-submergence rescue vehicle – Chinese Navy submarine rescue submersible
8A4-class ROUV – Chinese work class remotely operated underwater vehicle

A

Contents: Top	0–9	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Aa–Ab

AAI underwater revolver – Six-round amphibious revolver for naval use
A Blueprint for Survival (cave diving) – Book on cave diving safety by Sheck Exley
ABISMO – Japanese remotely operated underwater vehicle for deep sea exploration
ABLJ – Configuration of diving buoyancy compensator

Ac

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Acceptable risk – Risk that is understood and tolerated
Accelerated decompression – Decompresssion using oxygen-rich breathing gases
Acoustic beacon – Device that emits a sound signal to aid location underwater
Acoustic positioning system – System for tracking and navigation of underwater vehicles or divers using acoustic signals
Active addition rebreather – Semi closed circuit rebreather type
Active cooling – Cooling methods that expend energy to cool a system or component
Active heating – Directed application of an external heat source to control thermal balance
Acute dysbaric disorder – Injury caused by short term exposure to pressure variation
Acute oxygen toxicity – Adverse effects of high partial pressures of oxygen on the central nervous system

Ad

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Adaptive diving – Scuba diving using techniques modified to compensate for disabilities
Adaptive Support Diver – Scuba diver trained to support divers with disabilities
Adjustable buoyancy life jacket (ABLJ) – Chest inflation type buoyancy compensator
Administrative controls – Class of occupational hazard control
ADS 2000 atmospheric diving system – US Navy armoured diving suit
ADS amphibious rifle – Russian bullpup assault rifle for combat divers
Advanced diver (disambiguation) – Ambiguous term
Advanced Diving Equipment Company – American manufacturer of surface supplied diving helmets
Advanced European Scientific Diver – A diver competent to organise a scientific diving team
Advanced Open Water Diver – Recreational scuba diving certification slightly above minimum entry level
Advanced open-water diver – Recreational scuba diving certification level slightly above minimum entry level
Advanced nitrox diver – Technical diving qualification to use multiple mixtures of oxygen enriched air
Advanced SEAL Delivery System – Former Navy SEAL mini-sub deployed from submarines
Advanced trimix diver – Recreational technical diving certification to use hypoxic trimix

Ae

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Aeris (dive gear) – American brand of scuba equipment
Aerosinusitis – Barotrauma of the sinuses
Aerospace Medical Association – Professional organization in aviation, space, hyperbaric and environmental medicine
Aer-Sub – Branding used by Cressi-Sub for scuba equipment

Af–Ag

AFLOLAUN – Apparatus for laying out line and underwater navigation
Aggressive decompression – Decompression practice accepting higher risk of DCS to reduce in-water time

Ai

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

AIDA Hellas – National representative of AIDA International in Greece
AIDA International (AIDA) – Worldwide rule- and record-keeping body for competitive breath-hold events
Air diving – Underwater diving using air as the breathing gas
Air embolism – Vascular blockage by air bubbles
Air-integrated dive computer – Dive computer which displays cylinder breathing gas pressure
Air integration – Use of the dive computer to display cylinder gas pressure
Airlift (dredging device) , also known as air-lift (dredging device) – Dredging device using injected air to move water and entrained load up a pipe
Airlift dredge – Dredging device using injected air to move water and entrained load up a pipe
Airlift dredging – Removing underwater sediment using an airlift pump
Air line – Tube or hose carrying a compressed air supply
Air-line diving , also known as airline diving – Basic mode of surface-supplied underwater diving
Airlock , also known as air-lock – Compartment for transfer between environments with different atmospheres
Air lock diving bell – Type of mobile pressure caisson
Air lock diving-bell plant – Underwater work support barge used at Gibraltar
Air spread – The topside base for surface-supplied air diving operations
Air top , also known as air top-up – Modifying or completing a gas blend by adding compressed air

Al

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Alert Diver – Quarterly magazine published by DAN
Algal bloom – Spread of planktonic algae in water
Alpazat cave rescue – Six British soldiers trapped in a flooded Mexican cave
Al-Sabehat – Iranian swimmer delivery vehicle
Alternative air source – Emergency supply of breathing gas for an underwater diver
Alternative air supply – Emergency supply of breathing air for an underwater diver
Alternative gas supply – Emergency breathing gas supply
Alternobaric vertigo – Dizziness resulting from unequal pressures in the middle ears
Altitude decompression – Reduction in ambient pressure due to ascent above sea level
Altitude diver – Diver competent to plan decompression at altitude
Altitude Diver – Diver qualification for the skills to decompress at altitude
Altitude diving – Underwater diving at altitudes above 300 m
Aluminaut – First aluminum hulled submarine

Am

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Ama (diving) – Japanese pearl divers
Ambient pressure – Pressure of the surrounding medium
Ambient pressure at depth – Pressure in an underwater environment
American Academy of Underwater Sciences (AAUS) – American diving standards organisation
American Canadian Underwater Certifications (ACUC) – Recreational diver training and certification agency
American Nitrox Divers International (ANDI) – Recreational diver training and certification agency
Amontons' law – Relationship between pressure and temperature of a gas at constant volume

An

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Anchor pattern – Arrangement of anchors allowing precise positioning of a vessel
Andersson, Erik – Swedish manufacturer of standard diving equipment
Ankle strap (diving) – Staps worn over the ankles of dry suits to prevent the boots from pulling off when in use
Ankle weights (diving) – Diver trim weights worn at the ankles
ANMP – Association nationale des moniteurs de plongée
ANSTI breathing simulator , also known as ANSTI machine , ANSTI breathing machine – Machine to measure work of breathing of diving apparatus
Anti-fog – Chemicals that prevent the condensation of water as small droplets on a surface
Anti-frogman techniques – Methods of protection from incursions by divers and swimmers
Antipodes (submersible) – Commercial submarine built in 1973
AN/WQX-2 – Diver detection sonar used in defense against underwater incursions
Anxiety – Unpleasant emotion

Ap

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

AP Diving – British manufacturer of underwater diving equipment
Apeks – British manufacturer of scuba diving equipment
Apnea blackout – Loss of consciousness caused by cerebral hypoxia towards the end of a breath-hold dive
Apnea finswimming , also known as Apnoea finswimming – Underwater swimming in a swimming pool using mask, monofin and holding one's breath.
Apparatus for laying out line and underwater navigation (AFLOLAUN) – Equipment used by early cave divers
Apparent weight – Weight of an object when a force additional to gravity is present
APS underwater rifle – Soviet underwater assault firearm firing unrifled steel flechettes

Aq

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Aqua Lung America – American company manufacturing recreational diving equipment
Aqua Lung/La Spirotechnique – French company manufacturing breathing apparatus and diving equipment
Aqua-Lung – Original name for open-circuit scuba equipment
Aquanaut – Diver who remains at depth underwater for longer than 24 hours
Aquarium diving – Occupational diving in large aquariums
Aquascope – Underwater viewing device
Aquathlon (underwater wrestling) – Competitive underwater wrestling
Aqueon – Diver powered propulsion device

Ar

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Archaeological diving – Method in underwater archaeology
Archaeology of shipwrecks – Study of human activity through the analysis of shipwreck artifacts
Archimède – French Navy bathyscaphe
Archimedes' principle – Buoyancy principle in fluid dynamics
Argox – Gas mixture occasionally used by scuba divers for dry-suit inflation
Army engineer diver – Armed forces occupation
Army Ranger Wing – Special operations force of the Irish Defence Forces
Artificial gills (human) – Hypothetical devices to extract oxygen from water
Artificial reef – Human-made underwater structure that functions as a reef
Artificial Reef Society of British Columbia (ARSBC) – Canadian non-profit to create artificial reefs for habitat enhancement and recreation
AR vest – Type of jacket harness for surface-supplied diving

As

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Ascending and descending (diving) – Procedures for safe ascent and descent in underwater diving
Ascent and descent (diving) – Procedures for safe ascent and descent in underwater diving
Ascent blackout – Loss of consciousness caused by cerebral hypoxia on ascending from a deep freedive
Ascent rate (diving) – Speed at which the diver ascends from a dive
Ascents and descents (diving) – Procedures for safe ascent and descent in underwater diving
Ascent to altitude after diving – A type of extended decompression
ASM-DT amphibious rifle – Russian folding stock underwater firearm
Asphyxia – Severely deficient supply of oxygen
Assisted ascent – An emergency ascent during which the diver is provided with breathing gas by another diver
Association nationale des moniteurs de plongée – French recreational diver training and certification agency
Association of Offshore Diving Contractors (AODC) – Precursor to International Marine Contractors Association
Association of Diving Contractors International (ADCI) – Non-profit organization for promoting standards and knowledge for commercial diving

At

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Atlantis ROV Team – High-school underwater robotics team from Whidbey Island, Washington, United States
Atmospheric diving suit – Articulated pressure resistant anthropomorphic housing for an underwater diver
Atmospheric diving system – Diving equiment that isolates the diver from ambient pressure
Atmospheric pressure diving , also known as atmospheric suit diving – Diving in an articulated pressure resistant anthropomorphic housing
Atmospheric pressure – Static pressure exerted by the weight of the atmosphere
Atrial septal defect – Human heart defect present at birth
Attitude (diver) – Alignment of the principle axes of a diver in the water

Au

Section contents: Top of section, Aa–Ab, Ac, Ad, Ae, Af–Ag, Ai, Al, Am, An, Ap, Aq, Ar, As, At, Au, Av

Australian Diver Accreditation Scheme (ADAS) – Australian based international occupational diver accreditation organisation
Australian Submarine Rescue Vehicle Remora – Diving bell operated by the Australian Navy
Australian Underwater Federation (AUF) – Governing body for underwater sports in Australia
Auto-dump valve (ADV) – Valve to release excess gas from a dry suit
Automatic diluent valve (ADV) – Demand valve to maintain volume of a rebreather loop
Autonomous diver , also known as Autonomous Diver or Autonomous scuba diver – International minimum standard for entry level recreational scuba diver certification
Autonomous Robotics Ltd – UK company developing an autonomous underwater vehicle
Autonomous underwater vehicle – Uncrewed underwater vehicle with autonomous guidance system
AUV-150 – Unmanned underwater vehicle in development in by Central Mechanical Engineering Research Institute
AUV Abyss – Autonomous underwater vehicle for mapping of the seabed and water column data collection

Av

Avascular necrosis (AVN) – Death of bone tissue due to interruption of the blood supply
Avelo (diving system) – Variable density scuba buoyancy control system
Avesta Jernverks AB – Swedish manufacturer of seamless steel gas cylinders

B

Contents: Top	0–9	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Ba

Bachrach, Arthur J. – American psychologist and administrator (1923–2011)
Back flow (plumbing) – Undesirable reversal of flow
Back gas – Scuba breathing gas carried on the back of the diver
Back kick (finning) – Finning technique to move backwards
Back-mounted scuba – Scuba set carried on the diver's back
Backplate and wing – Type of back-mount scuba harness
Backscatter – Reflection which reverses the direction of a wave, particle, or signal
Backup diving equipment – Equipment carried in case of failure of the primary equipment
Backward kick (finning) – Finning technique to move backwards
Bagwork (concrete placement) – Method of concrete placement
Bail-out cylinder , also known as bailout cylinder – Emergency gas supply cylinder carried by a diver
Bailout (diving) – To switch over to an emergency system during a dive
Bailout block – Valve block on diver's equipment for switching between main and emergency gas supply
Bailout bottle – Emergency gas supply cylinder carried by a diver
Bailout gas – Emergency breathing gas supply carried by the diver
Bailout rebreather – Diving rebreather carried as an emergency gas supply
Bailout set – Emergency gas supply scuba carried by a diver
Bailout system – System to provide emergency breathing gas to a diver
Bailout to emergency gas supply – Diver switching to backup breathing gas
Bailout to open circuit , also known as bail out to open circuit – Abort a rebreather dive and surface using open circuit scuba
Bailout to rebreather – Use of a closed circuit breathing apparatus as an emergency gas supply
Bailout valve – Valve opening the supply of emergency breathing gas
Bailout valve (rebreather) – Valve on rebreather mouthpiece to switch to emergency gas supply
Baited remote underwater video – Equipment for estimating fish populations
Band mask – Heavy duty full-face diving mask for surface-supplied diving
Barodontalgia – Tooth pain caused by ambient pressure change
Barostriction – Obstruction of pressure equalization passages
Barotrauma – Injury caused by external fluid pressure
Barotrauma of ascent – Injuries caused by a reduction in ambient pressure
Barotrauma of the ear – Pressure injury to the ears
Barotraumas of decompression – Injuries caused by a reduction in ambient pressure
Barton, Otis – American diver and actor (1899–1992)
Basic Cave Diving: A Blueprint for Survival – Book on cave diving safety by Sheck Exley
Basic dive boat – Dive boat with minimal facilities
Basic life support – Emergency medical care by first responder
Bathyscaphe – Free-diving self-propelled deep-sea submersible

Be

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Beebe, William – American ornithologist, marine biologist, entomologist, and explorer (1877–1962)
Behnke, Albert R. – US Navy physician and diving medicine researcher
Belize Barrier Reef – Series of coral reefs straddling the coast of Belize
Bell-bounce dive – Surface-oriented diving in a closed bell
Bell bounce diving – Surface oriented diving using a closed bell
Bell cursor – Device to guide and control a diving bell near and above the surface
Bell gas panel – Manifold of hoses and cables provifing services to a diving bell and divers
Bell handling system – Launch and recovery equipment for a diving bell
Bell harness – Underwater diving safety haeness
Bell stage – Platform below the chamber of a closed diving bell
Bell umbilical – Bundle of hoses and cables providing services to a diving bell
Bellman (diver) – Diver working as standby diver and umbilical attendant from a diving bell
Bellman (diving) – The member of a dive team who acts as stand-by diver and tender from the diving bell
Bellows counterlung – Type of rebreather volume compensation component
Benemec Oy – Manufacturer of dive computers
Benign water – Diving environment with very low risk
Benign water diving – Diving in environments of low risk
Bering Sea Gold – Television series
Bering Sea Gold: Under The Ice – Discovery Channel reality television series
Bert, Paul – French zoologist, physiologist and politician (1833–1886)
Beuchat – French manufacturer of underwater diving equipment

Bi

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Bifin – Swimfin type with single foot pocket
Bikkers – Dutch manufacturer of standard diving equipment
Biological hazard – Biological material that poses serious risks to the health of living organisms
BioMarine – American manufacturer of diving rebreathers

Bl

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Blackpool decompression tables – Decompression tables for compressed air work
Black-water (diving) – Oceanic mid-water at night
Black-water diving – Open ocean mid-water diving at night
Blackout of ascent – Loss of consciousness caused by cerebral hypoxia on ascending from a deep freedive
Blauhöhle – Flooded cave system in Southern Germany
Blood–air barrier – Membrane separating alveolar air from blood in lung capillaries
A Blueprint for Survival – Book on cave diving safety by Sheck Exley
Blood shift – Set index article
Blood shift (diving) – Blood flow to the extremities redistributed to the head and torso during a breathhold dive
Blood–air barrier – Membrane separating alveolar air from blood in lung capillaries
Błotniak – One-man wet cabin underwater craft designed in Poland in 1978
Blue Grotto (Malta) – Sea caverns in Malta
Blue hole – Marine cavern or sinkhole, open to the surface, in carbonate bedrock
Blue Hole (New Mexico) – Sinkhole used for scubadiving in New Mexico, United States
Blue Hole (Red Sea) – Submarine sinkhole north of Dahab, Egypt
Blue Lake (Utah) – Large geothermal pond in Utah, U.S.
Blue-water diving , also known as blue water diving – Diving in mid-water where the bottom is out of sight
Blue-water (diving) – Oceanic mid-water
Blue-water downline – A weighted line suspended from a floating support in deep water

Bo

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Boarding stirrup – A suspended step to help divers lift themselves from the water into a boat
Boat diving – Procedures specific to diving from boats
Boaty McBoatface – British autonomous underwater vehicle
Bolt snap – Sprung slide gated snap hook
Bond, George F. – US Navy physician and diving medicine and saturation diving researcher
Booster pump – Machine to increase pressure of a fluid
Bottom gas – Gas breathed during the deep part of a dive
Bottom time – Elapsed time underwater until th start of ascent to the surface
Bottom timer – An electronic instrument that records depth and elapsed time data on an underwater dive
Bounce dive – Non-saturation dive profile with meaning depending on context
Boyle, Robert – Anglo-Irish scientist (1627–1691)
Boyle's law – Relation between gas pressure and volume

Br–Bs

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Bradner, Hugh – American physicist, neoprene wetsuit inventor (1915–2008)
Braile , also known as brail (diving) – Metal strap for clamping the collar of a standard diving suit to the corselet
Brazilian commando frogmen – GRUMEC is the special forces unit of the Brazilian Navy
Breaking wave , also known as surf – Wave that becomes unstable as a consequence of excessive steepness
Breastplate (diving) , also known as corselet (diving) – Lower part of a heavy diving helmet
Breath-hold blackout – Loss of consciousness caused by cerebral hypoxia towards the end of a breath-hold dive
Breathing – Process of moving air in and out of the lungs
Breathing air – Air quality suitable for safe breathing
Breathing air compressor – Machine that compresses atmospheric air at breathing gas quality
Breathing apparatus – Equipment allowing or assisting the user to breath in a hostile environment
Breathing gas – Gas used for human respiration
Breathing gas analysis – Detection and measurement of components of a breathing gas
Breathing gas quality – Purity requirements for gases for human breathing
Breathing gas reclaim system – Equipment to recover helium based breathing gas after use by divers
Breathing gas regulator – Mechanism to control the pressure of a breathing gas
Breathing gas switch – Changing between breathing gasses of different composition while diving
Breathing loop – Breathing gas circuit in a rebreather
Breathing performance of regulators , also known as breathing regulator performance – Capacity of breathing regulators to function as specified
Breathing regulator – Mechanism to control the pressure of a breathing gas
Breathing set – Equipment allowing or assisting the user to breath in a hostile environment
Breathing tube (breathing apparatus) – Tube through which to breath ambient pressure air
Briggs Marine – A marine services company based in the United Kingdom
British commando frogmen – Special Boat Service, whose members are drawn largely from the Royal Marines
British Divers Marine Life Rescue – United Kingdom charity organisation
British Freediving Association (BFA) – British affiliate to AIDA International
British Octopush Association (BOA) – National body for underwater hockey in the United Kingdom
British Sub-Aqua Club (BSAC) – Recreational diving club, training and certification agency based in the UK
British Underwater Sports Association (BUSA) – British affiliate to the world underwater federation sports committee.
Brubakk, Alf O. – Norwegian decompression researcher (1941–2022)
BRUV – Video system for estimating fish populations
BSAC First Class Diver – Recreational diver competent to lead a group of divers carrying out a project
BSAC London Branch – Original British Sub-Aqua Club branch

Bu–By

Section contents: Top of section, Ba, Be, Bi, Bl, Bo, Br–Bs, Bu–By

Bubble decompression model – Decompression models based on limiting growth of bubble nuclei
Buddy bottle – Alternative name for scuba bailout set
Buddy breathing – Technique for sharing breathing gas from a single mouthpiece
Buddy check – Pre-dive safety checks carried out by two-diver dive teams
Buddy diver – Person diving by the buddy system
Buddy diving – Practice of mutual monitoring and assistance between two divers
Buddy line – A tether between two scuba divers to prevent separation in low visibility
Buddy separation – Situation where dive buddies are not close enough to communicate
Buddy separation procedure – Standard procedure for dive buddy separation
Bühlmann, Albert A. – Swiss physician and decompression researcher (1923–1994)
Bühlmann decompression algorithm , also known as Buhlmann algorithm – Mathematical model of tissue inert gas uptake and release with pressure change
Bühlmann decompression model – Mathematical model of tissue inert gas uptake and release with pressure change
Built-in breathing set – System for supply of breathing gas on demand within a confined space
Built-in breathing system (BIBS) – System for supply of breathing gas on demand within a confined space
Built-in breathing system regulator – Hyperbaric chamber breathing regulators that exhaust externally
Buoyancy – Upward force that opposes the weight of an object immersed in fluid
Buoyancy compensator (BCD), also known as buoyancy control device – Equipment for controlling the buoyancy of a diver
Buoyancy compensator inflation hose – Inflation gas supply hose on scuba regulator
Buoyancy control (disambiguation)
Buoyancy control in scuba diving , also known as buoyancy control (scuba) , or buoyancy control (scuba diving) – Essential safety skill
Buoyancy control equipment – Diving equipment primarily intended to modify buoyancy of the diver
Buoyancy control skills – Skills of maintaining neutral buoyancy on scuba
Buoyancy control with a rebreather – Closed circuit scuba diving skill
Buoyancy engine – Device that alters a body's buoyancy to provide propulsion
Buoyant ascent – Type of emergency ascent in diving
Buoyant tethered ascent , also known as Emergency tethered ascent – Positive buoyancy emergency ascent using a reel upline
Burst disc , also known as rupture disc – Non-closing over-pressure relief device
Byford Dolphin – Semi-submersible offshore drilling rig
Byford Dolphin diving bell accident – Explosive decompression of an occupied saturation chamber

C

Contents: Top	0–9	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

Ca–Cc

Caisson (engineering) – Rigid structure to provide workers with a dry working environment below water level
Caisson gauge – High precision pressure gauge for pressure vessels for human occupancy
California Advisory Committee on Scientific and Technical Diving – Precursor to the American Academy of Underwater Sciences
Cam band , also known as camband , cam strap , or camstrap – Strap with locking buckle to hold scuba cylinder on BCD harness
Canadian Armed Forces Divers – Underwater divers employed by any of the Canadian armed forces
Canister light – Dive light with battery pack and light head connected by cable
Canoe and kayak diving – Recreational diving from a canoe or kayak
Canoe diving – Recreational diving from a canoe
Capernwray Dive Centre – Flooded quarry in Lancashire, England, used as a recreational dive site
Carbon dioxide retention – A tendency to retain abnormally high tissue carbon dioxide levels
Carbon dioxide scrubber – Device which absorbs carbon dioxide from circulated gas
Carbon dioxide scrubbing reaction – Chemical reactions that remove carbon dioxide from air
Carbon monoxide poisoning – Toxic effects of carbon monoxide
Carleton CDBA – Military rebreather by Cobham plc
Carmellan Research – British manufacturer of diving rebreathers
Cascade filling – Efficient system of filling from multiple gas storage cylinders
Cascade filling system – Filling pressurized gas from a series of storage cylinders
Cascade storage system – High pressure gas storage system set up for cascade filling
Catalina Cylinders – American manufacturer of aluminum gas cylinders
Catastrophic dry suit flooding – Major leak of water into a dry suit
Caustic cocktail – Mixture of water and strong alkali components from a flooded rebreather scrubber
Cavalero-Champion – French manufacturer of underwater diving equipment
Cave Divers Association of Australia (CDAA) – Association to represent cave divers and administrate and support cave diving in Australia
Cave diving – Diving in water-filled caves
Cave Diving Group (CDG) – UK based cave diver training and certification agency
Cave diving helmet – Impact protection equipment worn on the head
Cave diving regions – Geographical distribution of cave diving venues
Cave diving regions of the world – Regions of the world where known cave diving venues exist
Cave line – Line used for navigation in flooded caves
Cave reel – Line holder used to lay and recover guideline in caves
Cavern diver – Certification for diving under a natural overhead within the zone of natural light
Cavern diving – Diving in the part of a cave where the exit is visible by natural light
C-card – Certification as competent to dive to a specified standard

Ce–Cg

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

C.E. Heinke & Co. Ltd. – British manufacturer of diving equipment
CEJN connector – Type of quick connector for dry suit inflation gas
Cenote – Natural pit or sinkhole that exposes groundwater underneath
Center for Maritime Archaeology and Conservation – Academic centre at Texas A&M University
Central nervous system oxygen toxicity – Adverse effects of exposure to a high partial pressure of oxygen
Cerberus (sonar) – Diver detection device
CGA 850 connector system – US standard connector between scuba regulator and cylinder valve

Ch

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

HMS Challenger K07 – Royal Navy saturation diving support vessel
Chamber operation – Operation of a hyperbaric chamber in support of underwater diving
Chamber operator – A person who operates a diving chamber
Charging pressure – Rated pressure for filling a pressurised gas container
Charles's law – Relationship between volume and temperature of a gas at constant pressure
Chase boat – A tender generally not carried by the main vessel
Checklist – Aide-memoire to ensure consistency and completeness in carrying out a task
Checkout dive – Short dive to test a skill or equipment
Chemical hazard – Non-biological hazards of hazardous materials
Chief of safety – Supervisor of the safety team at a freediving competition
Christmas tree ladder – Ladder with rungs cantilevered from a central rail
Chronic dysbaric disorder – Injury caused by long term or multiple exposure to pressure variation
Chronic oxygen toxicity – Effects of long term exposure to high oxygen concentration

Ci

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

Circular search – Procedure for finding underwater targets
Circulatory system – Organ system for circulating blood in animals
Cis-Lunar – Manufacturer of electronically controlled closed-circuit rebreathers for scuba diving
Civil liability in recreational diving – Legal duty of care, negligence and liability in recreational diving

Cl

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

Clarke, John R. – American scientist and underwater breathing apparatus authority
Classification of underwater activities – Classification of underwater diving activities by occupational field
Cleaning and disinfection of personal diving equipment – Prevention of infection by shared or contaminated equipment
Clearance diver – Navy diver specialist with explosives
Clearance Divers Life Support Equipment (CDLSE) – British military electronically controlled closed circuit rebreather
Clearance diving – Military diving work involving underwater demolition and work with explosives
Clearance Diving Branch (RAN) – Diving unit of the Royal Australian Navy
Clearing a diving mask – Removing water from a flooded mask underwater
Clip-on weight – Small weights used to make fine adjustments to a diver's ballast
Close call – Incident that could have caused harm
Closed bell – Hyperbaric chamber for transporting divers vertically through the water
Closed bell emergency procedures – Standard procedures for use in common surface-supplied closed bell diving emergencies
Closed circuit breathing apparatus , also known as closed-circuit breathing apparatus – Apparatus to recycle breathing gas
Closed-circuit rebreather , also known as Closed circuit rebreather – Breathing apparatus
Closed circuit rebreather set point – Settings for maximum and minimum allowable oxygen partial pressure
Closed circuit scuba – Self contained underwater breathing apparatus which recycles exhaled breathing gas
Closed circuit bailout – Emergency gas supply from an independent closed circuit rebreather
Closed-circuit oxygen rebreather – Apparatus to recycle breathing gas
Closed diving bell – Hyperbaric chamber for transporting divers vertically through the water
Clump weight – A heavy weight suspended on cable used to guide a diving bell

Cm

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

CMAS* scuba diver , also known as CMAS one-star scuba diver – Entry level recreational diving certification from CMAS
CMAS** scuba diver , also known as CMAS two-star scuba diver or CMAS** Diver – Autonomous recreational scuba diving certification
CMAS*** scuba diver , also known as CMAS three-star diver – Fully trained and experienced recreational diver
CMAS**** scuba diver , also known as CMAS four-star diver – A three-star diver with a high level of competence and broad experience
CMAS Europe – Non-profit branch of the world underwater federation representing European affiliates
CMAS Scientific Committee – Committee of the World Underwater Federation
CMAS Two Star Instructor – CMAS instructor certified to train all core levels of diver
CMAS Three Star Instructor – CMAS diving instructor trainer
CMAS Instructors of South Africa (CMAS-ISA) – Member federation of CMAS for South Africa

Co

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

Coastal dive site – Sites in the sea near the coastline
Cochran Undersea Technology – American manufacturer of dive computers
Code of practice – Set of written rules which specifies how people working in a particular occupation should behave
Code of Practice for Scientific Diving (UNESCO) – Principles for the safe practice of diving for science
Code of Practice for Scientific Diving: Principles for the Safe Practice of Scientific Diving in Different Environments – Document published by UNESCO
Cold shock response – Physiological response to sudden exposure to cold
Cold-water diving – Underwater diving in water that is cold enough to require special equipment
Comando Raggruppamento Subacquei e Incursori Teseo Tesei – Italian special forces diving unit
Combat rubber raiding craft – Rubberised fabric tactical inflatable boat used by the US Navy
Combat sidestroke – Variation of side-stroke swimming used by United States Navy SEALs
Combined gas law – Combination of Charles', Boyle's and Gay-Lussac's gas laws
Comex therapeutic table CX 30 , also known as Comex 30 table – A hyperbaric treatment schedule developed by Comex
Comhairle Fo-Thuinn (CFT) – Governing body for recreational diving and underwater hockey in Ireland
Commando Hubert – Combat swimmer unit of the French Navy
Commandos Marine – Special operations forces of the French Navy
Commandos Military Unit , also known as Jednostka Wojskowa Komandosów (JWK) – Polish special operations unit
Commercial diver – Trained and registered professional diver
Commercial diver registration in South Africa – Registration of commercial divers by the South African Department of Employment and Labour
Commercial diver training – Processes by which people learn to dive safely for industrial applications
Commercial diving – Professional diving on industrial projects
Commercial diving school – Place where commercial diving skills are trained and assessed
Commercial offshore diver – Professional diver working offshore
Commercial offshore diving – Professional diving in support of the oil and gas industry
Communications panel – Surface control panel for underwater diving voice communications system
Compagnie maritime d'expertises – French offshore diving contractor
Compass grid search – Technique for finding underwater targets
Compass search – Search patterns controlled by compass directions
Competence (human resources) – Ability of a person to do a job properly
Competitive apnea – Competitive breathhold diving
Competitive freediving – Breathold diving competition disciplines
Competitive spearfishing – Hunting of fish underwater on breath-hold using a hand-loaded spear
Composite-Beat Engel – Swiss manufacturer of composite helmets
Compressed air – Air under a pressure greater than atmospheric
Compressed Gas Association (CGA) – American trade association for industrial and medical gas industries
Compression arthralgia – Joint pain caused by fast compression to high ambient pressure
Compressor diving – Crude mode of surface-suplied air diving
Compressor operator – Person competent to operate a diving air compressor
Concentration – Ratio of part of a mixture to the whole
Concentration gradient – Variation of concentration of a component of a mixture over distance
Confédération Mondiale des Activités Subaquatiques (CMAS) – International organisation for underwater activities
Confined water (diving) – A diving environment that is enclosed and bounded sufficiently for safe training
Confined water diving – Diving in water which is enclosed and limited in extent
Conrad Limbaugh Award for Scientific Diving Leadership – Annual award of the AAUS for contribution in scientific diving safety and leadership
Conservatism (diving) – Approach to risk reduction for decompression
Conservative decompression – Decompression practices of reduced risk
Constant flow breathing apparatus – Equipment providing a constant flow of breathing gas
Constant flow regulator – Gas pressure control regulator which provides a calibrated output
Constant mass flow regulator – Gas pressure regulator with a constant mass flow delivery
Constant weight apnea – Freediving discipline
Constant weight bi-fins – Competitive freediving discipline
Constant weight without fins – Freediving discipline
Contaminated water – Water containing high levels of hazardous materials
Contaminated water diving – Occupational diving in contaminated water
Continental Shelf Station Two – Undersea research habitat in the Red Sea
Contingency plan – A plan in case something unexpected occurs
Continuous blending and compression – Gas blending by constant flow mixing and analysis
Continuous decompression – Decompression without specific stops at given depths
Continuous flow breathing apparatus – Equipment providing a constant flow of breathing gas
Continuous guide line , also known as continuous guideline – Cord that can lead a scuba diver to open water
Contraindications for hyperbaric medicine – Reasons to avoid therapeutic compression
Controlled buoyant lift – A technique used by scuba divers to raise an incapacitated diver to the surface
Controlled emergency swimming ascent (CESA) – Emergency procedure for scuba divers when out of air
Coral reef – Outcrop of rock in the sea formed by the growth and deposit of stony coral skeletons
Coral Reef Alliance – Non-profit, environmental NGO focused on protecting coral reefs
Coral reef protection – Modifying human activities to reduce impact on coral reefs.
Correct scuba weighting – Weighting for scuba diving which works best most of the time
Corselet (diving helmet) – Part of a diving helmet supported by the shoulders
Cosmos CE2F series – Italian swimmer delivery vehicles
Counterlung – Volume compensating device in a rebreather

Cr

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

Cracking pressure – Pressure difference over the diaphragm needed to open a demand valve
Cramp – Pathological, often painful, involuntary muscle contraction
Cressi-Sub – Italian manufacturer of recreational diving and swimming equipment.
Crewed submersible – Small watercraft able to navigate under water
Crew resource management – Air crew communication and decision-making training
Critical flicker fusion frequency – Concept in the psychophysics of vision
Critical pressure for the dive profile – Minimum safe pressure to start a planned dive profile
Critical pressure of ascent – Minimum safe gas pressure to start ascent from a given depth and time to surface
Critical pressure of descent – Minimum safe pressure to start a planned dive profile
Critical pressure of exit – Minimum safe pressure to turn a penetration dive
Critical pressure of turnaround – Minimum safe pressure to turn a penetration dive
Critical pressure (scuba) – Breathing gas minimum safe pressure for starting specified activity
Cross altitude corrections – Adjustments to the US Navy decompression tables to allow for altitude
Cryogenic rebreather – Rebreather that removes CO2 by freezing it out using heat exchange with liquid oxygen

Cu

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

CUMA – Canadian military diving rebreather
Current (hydrology) – Flow of water in a stream caused by gravity
Current shear – Variation of flow rate transverse to flow direction
Current (stream) – Flow of water in a natural watercourse due to gravity
CURV – Early remotely operated underwater vehicle

Cy

Section contents: Top of section, Ca–Cc, Ce–Cg, Ch, Ci, Cl, Cm, Co, Cr, Cu, Cy

Cylinder band – Straps to clamp two scuba cylinders together
Cylinder pressure gauge – Instrument for measuring gas pressure in a storage cylinder
Cylinder valve (disambiguation)

Contents: Top	0–9	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z

Index of underwater diving: A–C

Contents

0–9

A

Aa–Ab

Ac

Ad

Ae

Af–Ag

Ai

Al

Am

An

Ap

Aq

Ar

As

At

Au

Av

B

Ba

Be

Bi

Bl

Bo

Br–Bs

Bu–By

C

Ca–Cc

Ce–Cg

Ch

Ci

Cl

Cm

Co

Cr

Cu

Cy

See also