FAQ ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers​

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An ongoing project of ScubaBoard
Brief explanations of terms and jargon used by divers and mariners.
Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member.

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scu·ba·board wi·ki​

/ˈsko͞obəbôrd wikē/​

noun​

1. a work in progress to use the collective knowledge of ScubaBoard's members to help members.
2. a website that allows collaborative editing of its content and structure by its users.

Remember

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Keyboard Shortcut Keys for your Internet browser’s "Find" function​

Microsoft Windows: Ctrl-F​

Apple Macs: Command-F​

Links to Posts​

Numerals, A, B, C, D, & E This post

F & G​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

H & I​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

J, K, L, & M​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

N, O, & P​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

Q & R​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

S & T​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

U, V, W, X, Y, & Z​

FAQ - ScubaBoard's Dictionary for Divers

ScubaBoard's Dictionary for Divers An ongoing project of ScubaBoard Brief explanations of terms and jargon used by divers and mariners. Please use "Report" to correct broken links, typos, or suggestions more definitions. ScubaBoard Staff will add new definitions and credit the member...

scubaboard.com

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0-9​

Reserved for new definitions

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A​

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AEDU

Admiralty Experimental Diving Unit in the UK​

— @Akimbo​

Alfa or Alpha flag

ICS standard flag meaning "I have a diver down; keep well clear at slow speed". Technically it is "Alfa", adopted by NATO phonetic alphabet​

— @Akimbo​

ADCI

Association of Diving Contractors International, merged with IMCA (International Marine Contractors Association)​

— @Akimbo​

ADS or Newtsuit

Atmospheric Diving Suit, a one-atmosphere deep submersible with mechanically articulated arms​

— @Akimbo​

AGE

Arterial Gas Embolism​

— @Akimbo​

Ambient Pressure (diving)

The pressure at the diver's current or anticipated depth​

— @Akimbo​

Anoxia (diving)

A condition of the body where no oxygen is present. Anoxia can occur if an individual stops breathing or breathes a gas mixture with no oxygen in it.​

— @Duke Dive Medicine​

AODC

Association of Offshore Diving Contractors​

— @Akimbo​

ATA

ATmospheres Absolute, a pressure measurement relative to a perfect vacuum​

— @Akimbo & @Duke Dive Medicine​

ATIS (Nautical)

Automatic Transmitter Identification System is a marine VHF radio system that sends and receives vessel identity, speed & heading, position, and other relevant data. Received data is displayed with GPS location and digital charts that include yours and surrounding vessels. Satellite-AIS (S-AIS) is used on oceangoing ships.​

— @Akimbo​

ATM

ATMosphere, a standard unit of pressure equal to:​

• 101.325 MPa
• 1.01325 Bar
• 14.6959 PSI
• 760 mmHg
• 10.06275861MSW
• 33.0142999 FSW

— @Akimbo​

AUV

Autonomous Underwater Vehicle. AUVs are most often used for acoustic and magnetic surveying of the ocean floor. They differ from ROVs because they do not have umbilicals to the support vessel or human operators.​

— @Akimbo​

B​

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Bailout Bottle

A HP cylinder used for backup breathing gas. The term is most commonly referring to umbilical supplied divers but can refer to Scuba divers.​

— @Akimbo​

Bar

The most common unit of Metric pressure used in diving. One Bar equals:​

• 14.5038 PSI
• 100 K Pascals
• 0.986923 Standard Atmospheres

— @Akimbo​

Barotrauma

An injury that results when a change in ambient pressure affects an enclosed, gas-filled space, either in the body (example: the middle ear) or adjacent to it (example: the air space in a face mask or in a drysuit).​

— @Duke Dive Medicine​

BC

Buoyancy Compensator​

— @Akimbo​

BCD

Buoyancy Compensator Device​

— @Akimbo​

Beam (Nautical)

Widest dimension of a vessel​

— @Akimbo​

Bends or Bent

A colloquial term that is in popular use for Decompression Sickness. The name originated with a popular dance when the Brooklyn Bridge was under construction, the Grecian Bend.​

— @Akimbo​

Berth (Maritime)

Bunk or bed, but can also be where a large ship docks​

— @Akimbo​

BIBS

Built-in Breathing System in decompression chambers and diving bells for emergency and treatment gasses.​

— @Akimbo​

Bilge (Nautical)

The lowest inside part of a vessel's hull where water collects​

— @Akimbo​

Binnacle (Nautical)

Waist-high stand or housing for a compass on a vessel​

— @Akimbo​

Blowdown or Blowing Down

Pressurizing a diving chamber or bell, slang in commercial diving​

— @Akimbo​

Boat hook (Nautical)

A pole with a small hook on the end to help snag things in the water (gaff hooks are sharp and for snagging fish)​

— @Akimbo​

Bow (Nautical)

Forward end of a vessel​

— @Akimbo​

Bow, stern, and spring lines (Nautical)

Ropes that tie the vessel to the dock​

— @Akimbo​

BPR

Back Pressure Regulators maintain a set pressure in the sensed line and a lower pressure on the outlet​

— @Akimbo​

BP/W

BackPlate & Wing style BCD​

— @Akimbo​

BSAC

British Sub-Aqua Club, a dive club that is heavily involved with diver training and certification.​

— @Akimbo​

BUD/S

Basic Underwater Demolition/SEAL, school for US Navy SEALs​

— @Akimbo​

Bulkhead (Nautical)

Partition wall on a vessel, may or may not be watertight​

— @Akimbo​

Bunk (Nautical)

Single bed, often stacked on a vessel. Navy sailors often call them racks​

— @Akimbo​

C​

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CAGE

Cerebral Arterial Gas Embolism​

— @Duke Dive Medicine​

Caisson Gauge

Pressure gauge that measures ambient pressure relative to to one ATA (sea level), the exact opposite of normal pressure gauges. The pressure sensing mechanism is sealed at one ATA, typically the Bourdon tube or helicoid. Commonly used inside decompression chambers and calibrated in Feet or Meters of Sea Water.​

— @Akimbo​

Cal Gas

Gas of known percentages used to calibrate gas analyzers. Recreational divers will typically calibrate analyzers against air and sometimes pure Oxygen. Deep diving operations use laboratory certified gas mixtures with Oxygen and Helium in a range appropriate for their operating depth.​

— @Akimbo​

Cam Band

A webbing band used to attach the BCD and harness to a diving cylinder and tightened by a cam mechanism​

— @Akimbo​

Catenary (Nautical)

The curve or sag in a line under tension, such as an anchor line.​

— @Akimbo​

CGA

Compressed Gas Association, a US trade association for industrial and medical gas supply industries​

— @Akimbo​

Chine (Nautical)

The line along the sides of a vessel formed by the intersection of the sides and bottom. Divers often swim along the chine to and from the anchor line​

— @Akimbo​

Christo-lube

Brand name of a widely used lubricant for for oxygen service, often Christo-lube MCG111​

— @Akimbo​

CMAS

Confederation of Underwater Activities, a Scuba confederation of training agency​

— @Akimbo​

CNS

Central Nervous System, generally refers to negative effects of DCS or Oxygen Toxicity in diving. More correctly, CNS is part of the nervous system consisting of the brain and the spinal cord.​

— @Akimbo & @Duke Dive Medicine​

CO

Chemical symbol for the Carbon Monoxide molecule, not to be confused with Carbon Dioxide.​

— @Akimbo & @Duke Dive Medicine​

CO2

Chemical symbol for the Carbon Dioxide molecule​

— @Akimbo & @Duke Dive Medicine​

Color temperature

The measurement of color expressed in degrees Kelvin. Bright sunlight is in the 6,000° K range.​

— @Akimbo​

Combat Swimmer

Military combatant using diving techniques​

— @Akimbo​

Compression Arthralgia or Compression Pains

Joint pain caused by compression of cartilage in very deep diving​

— @Akimbo​

CPR

Cardio-Pulmonary Resuscitation​

— @Akimbo​

D​

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DAN

Diver's Alert Network is the largest diving safety organization and offers dive accident insurance through insurance companies​

— @Akimbo​

Davit (Nautical)

Rotating fixed boom with a lifting system​

— @Akimbo​

DC

Decompression Computer​

— @Akimbo​

DCI

Decompression Illness is a broad term used to capture diving disorders caused by the effects of gas bubbles in the body. DCI includes decompression sickness (DCS), arterial gas embolism (AGE), and DCS symptoms brought about by venous gas emboli (bubbles) that cross into the arterial system through a shunt in the body, e.g. a patent foramen ovale or intrapulmonary shunt.​

— @Duke Dive Medicine​

Deco

Slang for Decompression​

— @Duke Dive Medicine​

Delta-P or ΔP

Differential or change in pressure. The Greek character Δ, or "Delta", denotes “change” in science.​

— @Akimbo​

DCS

1. Decompression Sickness​

2. Other common names include:​

• DCI (Decompression Illness) which includes AGE (Arterial Gas Embolism)
• Bends or Bent, slang from the name of a popular dance when the Brooklyn Bridge was under construction, the Grecian Bend.
• Caissons Disease, because Caisson workers or Sandhogs are also subject to DCS
• Chokes (archaic)
• Divers' Disease
• Divers' Condition
• Diver's Palsy
• Decompression Disease
• Compressed Air Illness
• Dysbaric Illness
• Tunnel Disease

— @Akimbo​

Deck (Nautical)

Floor on a vessel​

— @Akimbo​

Deep Mix

Typically, HeO2 mixture used by saturation divers at their working depth.​

— @Akimbo​

DDC

Deck Decompression Chambers are primarily used for treating DCS in recreational divers and living chambers for Saturation Divers​

— @Akimbo​

Dil

Diluent - A volume makeup gas used in rebreather diving to keep the loop filled with breathable volume along with added oxygen. Up to 40m, dil can be air. Below that depth, Helium is added to decrease nitrogen content and gas density. ​

— @rsingler ​

DIN

Deutsches Institut für Normung, defines standard DIN 477 that is widely used for Scuba valves and regulators​

— @Akimbo​

DIR

Doing It Right, system of Scuba diving​

— @Akimbo​

DM

Divemaster​

— @Akimbo​

Diving Bell (closed)

A submersible pressure chamber with a bottom hatch primarily used in saturation diving​

— @Akimbo​

Diving Bell (open)

An open-bottom bell with a breathable gas bubble that is a least large enough for one or more divers to get their heads out of the water. Typically used for in-water decompression and/or an emergency sanctuary.​

— @Akimbo​

Diving Locker

Storage area for diving equipment, originating on Navy ships referring to small compartments (shipboard rooms)​

— @Akimbo​

Dive Super

Diving Supervisor or Superintendent, typically in military of commercial diving operations​

— @Akimbo​

DP (Nautical)
Dynamic Positioning

— @Akimbo​

DPV

Diver Propulsion Vehicle, typically a tubular housing containing batteries, controllers, and a motor driving a single propeller​

— @Akimbo​

Draft (Nautical)

Waterline to the bottom of the keel distance on a the vessel​

— @Akimbo​

DSLR (photography)

Digital Singe Lens Reflex camera​

— @Akimbo​

DSO

Diving Safety Officer, typically required by government and scientific diving operations​

— @Akimbo​

DSV

Diving Support Vessel, most commonly designating vessels used in commercial diving. DSV can refer to the class of vessel or precede the vessel name.​

— @Akimbo​

Dump Valve (Diving)

A large LP valve that rapidly opens to release gas, usually by pulling a lanyard. Most often found on BCs, DSMBs, and lift bags.​

— @Akimbo​

E​

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EAD

Equivalent Air Depth used in Nitrox calculations​

— @Akimbo​

EADD

Equivalent Air Density Depth​

— @Miyaru​

EAN

Enriched Air Nitrox​

— @Akimbo​

ECU

Environmental Control Unit used in decompression chambers to manage CO2, humidity, and temperature.​

— @Akimbo​

Embolism (Diving)

Popular verbal shorthand for Arterial Gas Embolism or AGE​

— @Akimbo​

EPIRB

Emergency Position Indicating Radio Beacon, GPS emergency beacon required on most licensed vessels​

— @Akimbo​

ETD

Eustachian Tube Dysfunction, a disorder in which the Eustachian tube (the small tube that connects the middle ear to the area behind the nasal passages) does not work properly.​

— @Duke Dive Medicine​

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Use Report to correct broken links, typos, or make suggestions.

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Continued in the next post

 

[The Mod Squad]

Continued from previous post

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F​

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FFM

Full Face Mask that covers a diver's eyes, nose, and mouth. They are generally used to protect divers from very cold water, contaminated water, and/or for voice communications. Recreational divers may use them to allow oral-nasal breathing. FFMs can be used for Scuba, surface-supplied, and saturation diving.​

— @Akimbo​

FFW

Feet of Fresh Water​

— @Akimbo​

Floodable Volume

The volume measured by a liquid in a container, most often used for the internal volume of a high pressure cylinder​

— @Akimbo​

Frenzel Maneuver

A hands-free alternative for equalizing to the Valsalva maneuver​

— @Akimbo​

FSW

Feet of Salt Water, generally referring to a depth equivalent that ultimately translates back to pressure for calculating decompression obligations​

— @Akimbo​

G​

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Galley (Nautical)

Kitchen and food prep area on a vessel​

— @Akimbo​

Galvanic Oxygen sensor

Electro-galvanic micro fuel cell that generates electrical current in direct proportion to the partial pressure of oxygen. Most commonly used in the medical and diving instrumentation and control systems.​

— @Akimbo​

Gas King or Gas Man

Technician who manages gas systems on saturation diving systems​

— @Akimbo​

Gauge Pressure

The difference in pressure indicated by a pressure gauge between ambient and the sensed pressure​

— @Akimbo​

GPS

Global Positioning System is a ubiquitous geolocation technology based on a series of satellites operated by the US Space Force. Integrated marine navigation systems combine GPS with digital marine charts and sometimes Radar, marine and satellite weather data, sonar, and/or marine topographic charts. Unfortunately, GPS satellite radio waves only penetrate water to a very shallow depth.​

— @Akimbo​

GPS Coordinates

GPS coordinates are expressed in degrees of Latitude and Longitude, which is the convention for marine navigation.​

— @Akimbo​

Gradient Factors

Most often referring to decompression conservatism variable settings in decompression computers.​

— @Akimbo​

GUE

Global Underwater Explorers​

— @Akimbo​

Gunnel or gunwale (Nautical)

Top rail around the outboard edge of the deck​

— @Akimbo​

GWS

Great White Shark​

— @tridacna​

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[The Mod Squad]

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H​

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Head (Nautical)

Bathroom or a toilet on a vessel​

— @Akimbo​

Haldane

John Scott Haldane’s name is widely associated with a number of decompression-related phrases because of his early work developing decompression theory and tables​

— @Akimbo​

Hard Ceiling

Shallow limit a diver can ascend due to physical barriers, typically in cave and wreck diving​

— @Akimbo​

HCVR

Hypercapnic ventilatory response, the body's increase in respiratory minute volume (RMV) in response to increased blood CO2 levels. Individual HCVR varies, which predisposes some individuals to hypercapnia during diving.​

— @Duke Dive Medicine​

HBOT

HyperBaric Oxygen Treatment, most often referring to non-diving medical treatment but may also be to treat DCS and barotrauma.​

— @Akimbo​

Heavy Gear

Augustus Siebe's original closed diving dress also known as:​

• Deep Sea (Diving) Gear
• Hard Hat Gear
• Submarine Armor
• Spun Copper
• Standard Diving Dress

— @Akimbo​

He

Chemical symbol for a Helium molecule​

— @Akimbo​

HeO2

Helium and Oxygen gas mixture derived from the symbols for the molecules. Note that HeO2 is a mixture and not a compound.​

— @Akimbo​

Hook (Nautical)

Slang for anchor​

— @Akimbo​

Hot Water Suit

Loose-fitting one-piece wetsuit with perforated tubes that distributes hot water pumped from the surface throughout the suit. Invented by George C Wiswell Jr in 1966 to support saturation diving.​

— @Akimbo​

HP

High Pressure, in recreational diving, most often referring to the pressure inside a Scuba cylinder and in dive shop compressor systems​

— @Akimbo​

HPNS

High Pressure Nervous Syndrome is a medical condition that effects very deep divers who are rapidly compressed​

— @Akimbo​

HSA

Handicapped Scuba Association, a Scuba training agency for physically and mentally challenged and their support divers​

— @Akimbo​

Hyperbaric

Pressure greater than at sea level, often referring to diving or medical treatment in a chamber.​

— @Akimbo​

Hypercapnia

A condition in which excess carbon dioxide (CO2) exists in the body; when measured, a generally accepted numerical value for hypercapnia is a partial pressure of dissolved CO2 in venous blood greater than 45 millimeters of mercury (mmHg).​

— @Duke Dive Medicine​

Hypothermia

A drop in the body's core temperature to less than 35°C (95° F) (Peiris AN, Jaroudi S, Gavin M. Hypothermia. JAMA. 2018;319(12):1290. doi:10.1001/jama.2018.0749)​

— @Duke Dive Medicine​

Hypoxia (medical/diving)

Inadequate oxygen reaching the tissues, typically from breathing gasses with a PPO2 that is too low.​

— @Akimbo​

I​

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IBCD

IsoBaric Counter Diffusion​

— @rsingler​

IEBT

Inner Ear BaroTrauma​

— @Duke Dive Medicine​

IPE

Immersion Pulmonary Edema, also known as swimming-induced pulmonary edema (SIPE) is a condition in which pulmonary edema (swelling in the lungs) develops rapidly during a dive or vigorous swim. (Moon RE. Immersion pulmonary edema: drowning from the inside. Undersea Hyperb Med. 2019;46(5):577-579.)​

— @Duke Dive Medicine​

IWR

In Water Recompression, treating DCS in the water instead of in a chamber.​

— @Akimbo​

IP

Intermediate Pressure, most often referring to the pressure between the first and second stage of a Scuba regulator​

— @Akimbo​

ISO

International Standards Organization​

— @Akimbo​

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Use Report to correct broken links, typos, or make suggestions.

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Continued in the next post

 

[The Mod Squad]

Continued from previous post

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J​

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J-valve

Scuba cylinder valve with a lever-activated reserve, largely obsolete​

— @Akimbo​

Jonline or Jon line

A short line or webbing with hooks, named after Jon Hulburt, used to decouple the jerking motion of an anchor line in rough seas from divers "hanging off" for decompressing.​

— @Akimbo​

JYC

Jacques-Yves Cousteau, the co-inventor of the Aqua Lung and world recognized undersea explorer, conservationist, and filmmaker.​

— @Akimbo​

K​

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K Bottle

Most common HP steel industrial gas cylinder in the US, 9.25" in diameter × 60" tall, approximately 50 Liter floodable volume.​

— @Akimbo​

K-valve

Standard Scuba cylinder valve for a single tank.​

— @Akimbo​

Keel (Nautical)

Fore-aft centerline structural member, round and flat bottom boats don't have true keels.​

— @Akimbo​

Kirby-Morgan

Dominant manufacturer of commercial diving helmets and FFMs. See Bev Morgan biography​

— @Akimbo​

Knot (Navigation & Maritime)

A unit of speed, equaling one nautical mile (6,080.20 feet or 1,853.245 Meters) per hour​

— @Akimbo​

L​

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Ladder (Nautical)

An actual ladder or stairs on a vessel​

— @Akimbo​

Lanyard (Diving)

A common nautical term that is most often used in recreational diving to describe a piece of small line that functions as a handle to open an dump valve or open a quick release device.​

— @Akimbo​

Lift Bag

A teardrop-shape open-bottom flexible bag used to float submerged objects by attaching and filling with air.​

— @Akimbo​

Line (Nautical)

Cordage of any size from twine to hawsers​

— @Akimbo​

Liveaboard

Dive charter boat with berthing and galley capacity of multi-day trips​

— @Akimbo​

Lockout

A diver exiting a diving bell or submarine.​

— @Akimbo​

LDS

Local Dive Shop​

— @Akimbo​

LP

Low Pressure, a relative term that varies widely by industry.​

— @Akimbo​

lm or Lumen

A standard unit of light measurement, typically used in diving to describe a flashlight/torch's output.​

— @Akimbo​

M​

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Main Deck (Nautical)

Typically the highest deck reaching bow to stern​

— @Akimbo​

Mains (Nautical)

Slang for main engines of a vessel​

— @Akimbo​

Marlinespike seamanship or Ropework (Nautical)

A traditional nautical term for skills relating to the all aspects of the use of rope or line.​

— @Akimbo​

MEBT

Middle Ear BaroTrauma​

— @Duke Dive Medicine​

MFW

Meters of Fresh Water​

— @Akimbo​

MOD

Maximum Operating Depth, which is calculated based on the Oxygen content of the breathing mixture.​

— @Akimbo​

Moonpool

A large opening or well in a vessel for diving bells and work systems, typically located close to the center of gyration for maximum stability.​

— @Akimbo​

MSW

Meters of Salt Water​

— @Akimbo​

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Use Report to correct broken links, typos, or make suggestions.

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Continued in the next post

 

[The Mod Squad]

Continued from previous post

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N​

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N2

Chemical symbol for a Nitrogen molecule​

— @Akimbo​

NAUI

National Association of Underwater Instructors, a Scuba training agency​

— @Akimbo​

Nautical Mile (Nautical /Navigation)

Originally defined as the meridian arc length corresponding to one minute or 1/60th of a degree of latitude. It is currently defined exactly as 1,852M or approximately 6,076' and 1.151 statute miles.​

— @Akimbo​

NDL

No Decompression Limit​

— @Akimbo​

Neck Dam

A resilient cone-shape seal used on drysuits and lightweight diving helmets​

— @Akimbo​

NEDU

US Navy Experimental Diving Unit​

— @Akimbo​

NOAA (Nautical & Diving)

National Oceanic and Atmospheric Administration in the US.​

— @Akimbo​

O​

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O2

Chemical symbol for Oxygen molecules, which consists of two Oxygen atoms​

— @Akimbo​

OC

Open Circuit, meaning that exhaled gas is expelled into the water as opposed to recycled.​

— @Akimbo​

OOA

Out of Air, commonly used to describe any event where a diver runs out of breathing gas on open circuit Scuba.​

— @Akimbo​

O-ring

A resilient toroidal seal that is widely used in hydraulic and pneumatic systems​

— @Akimbo​

OC

Open Circuit Scuba, as opposed to Closed Circuit Rebreather Scuba​

— @Akimbo​

Oxtox or Oxygen Toxicity

A medical condition where excessive oxygen becomes toxic to humans under hyperbaric conditions.​

— @Akimbo​

Overhead (Nautical)

Ceiling on a vessel​

— @Akimbo​

P​

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PADI

Professional Association of Diving Instructors, a Scuba training agency​

— @Akimbo​

Pascal

Pascal, or Pa, is the standard metric unit of pressure, though not necessarily the most widely used. It is a derived unit defined in International System of Units or Système International (SI).​

• 1 PSI = 6.89476 KPa
• 1 Bar = 100.0000393 KPa
• 1 standard atmosphere (atm) = 101.325 KPa

— @Akimbo​

Passageway (Nautical)

Corridor or hallway on a vessel​

— @Akimbo​

Pilot house (Nautical)

Where primary steering, navigation, and engine controls are located​

— @Akimbo​

PDC

Personal Decompression Computer​

— @Akimbo​

PFO

Patent Foramen Ovale. The foramen ovale is an opening between the left and right atria, or upper chambers, of the fetal heart. In utero, it allows a portion of the fetal blood supply to bypass the lungs. It typically closes at birth, but remains open, or patent, in roughly 25-30% of the adult population.​

— @Duke Dive Medicine​

Pitch (Nautical)

Rotational around an axis that is perpendicular to the longitudinal axis of a vessel in swells. Pitch can also be a measurement of propeller blades.​

— @Akimbo​

PLB

Personal Locator Beacon, electronic position indicating device, similar to an EPIRB, that is small enough for divers to carry in a housing.​

— @Akimbo​

Pneumofathometer

A system to monitor a surface-supplied diver's depth by blowing the water out of a small hose bundled in their umbilical that is connected to a large precision pressure gauge on the surface.​

— @Akimbo​

Port (Nautical)

Left side of vessel when facing the bow​

— @Akimbo​

Prop (Nautical)

Slang for propeller​

— @Akimbo​

PSD

Public Safety Diver​

— @Akimbo​

PSI

Pounds per Square Inch, the standard unit of pressure in the Imperial system.​

• 1 Bar = 14.5038 PSI
• 1 ATM = 14.7 PSI

— @Akimbo​

PTC

Personal Transfer Capsule is a term that originated in the US Navy for diving bells used for saturation diving​

— @Akimbo​

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Use Report to correct broken links, typos, or make suggestions.

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Continued in the next post

 

[The Mod Squad]

Continued from previous post

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Q​

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QD or Quick Disconnect

Pneumatic or hydraulic quick coupler fittings, most commonly used on IP hoses to BC power inflators and drysuits in recreational diving.​

— @Akimbo​

R​

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Recompression

Re-compressing a diver, usually in a chamber, for DCS treatment or Sur-D-O2 ​

— @Duke Dive Medicine​

Regulator (Diving)

A preset pressure-reducing valve (first stage) and demand regulating valve (second stage) that delivers breathing gas to Scuba divers. The most popular models connect the two separate stages with a medium pressure hose.​

— @Akimbo​

Regulator (Industrial)

A pressure-reducing valve for hydraulic and pneumatic systems that can be preset, pressure adjusted (dome-loaded), or manually adjusted (hand-loaded).​

— @Akimbo​

Reped or Repet

Verbal shorthand for REPEtitive Dive, or more than one dive in a 24 hour period.​

— @Akimbo & @Duke Dive Medicine​

RIB (Nautical)

Rigid Inflatable Boat​

— @Akimbo​

RMV

Respiratory Minute Volume, volume of gas inhaled or exhaled from a person's lungs per minute, usually expressed in ambient Liters.​

— @Akimbo​

Roll (Nautical)

Side to side motion of a vessel in swells​

— @Akimbo​

RNT

Residual Nitrogen Time used to calculate decompression obligations for repetitive dives​

— @Akimbo​

ROV

Remotely Operated Vehicle used primarily in the offshore oil industry and marine science​

— @Akimbo​

Rudder (Nautical)

Flat plates for steering or maneuvering, usually aft of propellers​

— @Akimbo​

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[The Mod Squad]

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S​

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SAC rate

Surface Air Consumption rate​

— @Akimbo​

Sample Bomb

A small HP gas cylinder use to collect gas for laboratory analysis, typically stainless steel with valves at both ends to allow thorough flushing.​

— @Akimbo​

Salon (Nautical)

Meeting room or lounge on a vessel, often includes dinning​

— @Akimbo​

SAR

Search And Rescue or Sea Air Rescue​

— @Akimbo​

Sat or Saturation Diving

A diving technique based on total tissue saturation, beyond which decompression obligations do not increase. Used primarily in military and commercial diving operations due to very high cost and support requirements.​

— @Akimbo​

Screw (Nautical)

Slang for propeller... but it may also be used for a fastener​

— @Akimbo​

Scope (Nautical)

Horizontal to vertical ratio of anchor line, but can also be slang for the radar display​

— @Akimbo​

Scupper (Nautical)

Drain holes for water to exit from weather decks​

— @Akimbo​

SDI

Scuba Diving International, a Scuba training agency​

— @Akimbo​

SCFM

Standard Cubic Feet per Minute, commonly used to describe compressor capacity​

— @Akimbo​

Seachest (Nautical)

A hull-mounted recess for seawater valves, usually protected by a grating​

— @Akimbo​

Seacock (Nautical)

A hull valve on a vessel​

— @Akimbo​

SEAL

An acronym for SEa Air Land, a covert special forces group in the US Navy.​

— @Akimbo​

Scrubber

A device that removes Carbon Dioxide from chamber or bell atmospheres, most often electrically driven fans and chemical absorbent canisters.​

— @Akimbo​

SCUBA or Scuba

Acronym for Self-Contained Underwater Breathing Apparatus. Commonly used as a noun and a verb.​

— @Akimbo​

SDC

Submersible Decompression Chamber is an old term for a diving bell​

— @Akimbo​

SLPM

Standard Liters Per Minute, commonly used to describe compressor capacity​

— @Akimbo​

Soft Ceiling

The shallow limit a diver can ascend due to decompression constraints​

— @Akimbo​

SPG

Submersible Pressure Gauge is a pressure gauge in a housing that maintains one ATA so it will not be changed with ambient pressure at depth​

— @Akimbo​

SPUMS

South Pacific Underwater Medicine Society​

— @Akimbo​

Squeeze

A colloquial term for barotrauma​

— @Duke Dive Medicine​

SSI

Scuba Schools International, a Scuba training agency​

— @Akimbo​

Starboard (Nautical)

Right side of vessel when facing the bow​

— @Akimbo​

Stateroom (Nautical)

Bedroom on a vessel, sometimes called a cabin.​

— @Akimbo​

Stern (Nautical)

Aft end of a vessel​

— @Akimbo​

SUBA

Self Contained Breathing Apparatus, most often referring to firefighting and mine safety equipment.​

— @Akimbo​

Submersible or Deep Submersible

A manned submarine with most of the propulsion and control systems outside of the pressure hull​

— @Akimbo​

Sur-D-O2

Surface Decompression using Oxygen is a common technique used by military ad commercial divers to minimize in-water decompression and complete it in a deck chamber.​

— @Akimbo​

Swim step (Nautical)

Platform aft on the transom near the waterline​

— @Akimbo​

T​

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TDI

Technical Diving International, a Scuba training agency​

— @Akimbo​

Transom (Nautical)

Relatively flat part of the hull at the stern of the vessel​

— @Akimbo​

Trimix

A breathing mixture of Nitrogen, Helium, and Oxygen commonly used for deep diving to reduce the effects of Nitrogen Narcosis and HPNS​

— @Akimbo​

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[The Mod Squad]

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U​

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UDT

Underwater Demolition Teams, the predecessors to the US Navy SEALs.​

— @Akimbo​

Umbilical

A collection of hoses and cables bundled or twisted together used by tethered divers; surface-supplied and operating from diving bells. It can also refer to bundles to underwater habitats and work support systems including hydraulic tools and cutting/welding rigs.​

— @Akimbo​

USN

United States Navy​

— @Akimbo​

V​

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Valsalva Maneuver

The most common method used by Scuba divers for equalizing ears​

— @Akimbo​

VENTID

Mnemonic for Vision Ears Nausea Twitching Irritation Dizziness, the most common but less severe symptoms of Oxygen Toxicity​

— @Akimbo​

Vessel (Nautical)

For the purposes of this thread, a general term that includes:​

• Boats of any size and purpose
• Inflatables
• Dinghys
• Yachts
• Barges
• Ships
• Submarines
• Manned deep submersibles
• Semi-submersibles and Swath vessels

— @Akimbo​

VHF (Nautical)

Technically, Very High Frequency but it is common slang for VHF Marine Radio​

— @Akimbo​

W​

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Weather Deck (Maritime)

Uppermost deck exposed to the weather​

— @Akimbo​

Wheel (Nautical)

Slang for steering wheel​

— @Akimbo​

Windlass (Nautical)

anchor winch (can apply to similar lifting aids)​

— @Akimbo​

WKPP

Woodville Karst Plain Project​

— @Akimbo​

WOB

Work Of Breathing, energy expended to inhale and exhale a breathing gas, usually expressed as work per unit volume per minute​

— @Akimbo​

X​

---

reserved for expansion

---

Y​

---

reserved for expansion

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Z​

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ZHL-16

Bühlmann decompression algorithm​

— @Akimbo​

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[The Mod Squad]

Continued from previous post

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U​

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UDT

Underwater Demolition Teams, the predecessors to the US Navy SEALs.​

— @Akimbo​

Umbilical

A collection of hoses and cables bundled or twisted together used by tethered divers; surface-supplied and operating from diving bells. It can also refer to bundles to underwater habitats and work support systems including hydraulic tools and cutting/welding rigs.​

— @Akimbo​

USN

United States Navy​

— @Akimbo​

V​

---

Valsalva Maneuver

The most common method used by Scuba divers for equalizing ears​

— @Akimbo​

VENTID

Mnemonic for Vision Ears Nausea Twitching Irritation Dizziness, the most common but less severe symptoms of Oxygen Toxicity​

— @Akimbo​

Vessel (Nautical)

For the purposes of this thread, a general term that includes:​

• Boats of any size and purpose
• Inflatables
• Dinghys
• Yachts
• Barges
• Ships
• Submarines
• Manned deep submersibles
• Semi-submersibles and Swath vessels

— @Akimbo​

VHF (Nautical)

Technically, Very High Frequency but it is common slang for VHF Marine Radio​

— @Akimbo​

W​

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Weather Deck Maritime

Uppermost deck exposed to the weather​

— @Akimbo​

Wheel (Nautical)

Slang for steering wheel​

— @Akimbo​

Windlass (Nautical)

anchor winch (can apply to similar lifting aids)​

— @Akimbo​

WKPP

Woodville Karst Plain Project​

— @Akimbo​

WOB

Work Of Breathing, energy expended to inhale and exhale a breathing gas, usually expressed as work per unit volume per minute​

— @Akimbo​

X​

reserved or expansion

---

Y​

reserved or expansion

---

Z​

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ZHL-16

Bühlmann decompression algorithm​

— @Akimbo​

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Use Report to correct broken links, typos, or make suggestions.

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End of Multipart post

 

[The Mod Squad]

reserved for expansion, ScubaBoard's Dictionary for Divers

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Use Report to correct broken links, typos, or make suggestions.