Diving Dictionary
Not sure what some of those diving terms mean? Take a look inside our easy Diving Dictionary to expand your dive vocabulary:
A
Ascent Rate - The rate you go up from your dive.. max 18 m/min.
Artificial Reef - Man made constructions, for corals to attach themself too
Apnea Diving - Breathhold diving, free diving, you dive with out scuba equipment on a single breath down.
Aluminium Cylinder - The material used in thailand and other hot environments. Corrode less than steel and the tanks are lighter.
Altitude Diving - Diving taking place at 300 m or more above sealevel.
Alternate Air Source - an extra airsource, used for your buddy in emergency. Also called the octopus.
Air Composition - The composition of gasses in an airmix. Normal air-21% oxygen, 79% nitrogen.
Advanced Diver - A diver who has taken the advanced open water course.
Absolute Pressure - The pressure surounding you at depth. both from the water and the air above.
B
Bar - You measure pressure in Bar or atmospheres.
Barotrauma - Pressure injuries.
BCD - Boyancy control device. The jacket that controls your Boyancy and keeps you scubaunit together.
Buddy Check - A predive safety check done together with your buddy.
Buoyancy - Your position in the water. Neutral: when you neither sink or floats, positive: when you float, Negative: when you sink
Burst Disk - A safety device on your tank that will release pressure from the tank if it gets overpressurized.
Breath Hold Diving - See apnea diving.
Bottom Time - The time from you descent till you are back on surface again.
Balanced Regulator - When your regulator is not effected by surrounding pressure or tank pressure. Same resistance through the whole dive.
C
Capillary Depth Gauge - Used especially for altitude diving. very accurate between 0-10 m.
Carbon Monoxide Poisoning - Caused by contaminated air - very unlikely. Symptoms are cherry red lips and fingerbeds, nausea and dizziness.
Cave Diving - Overhead environment. Diving in a cave deeper than 40m linear or out of the natural light zone.Special training required.
Cavern diving - Overhead environment. Diving within 40m linear from the surface and the natural light zone. Special training required.
Certification - At the end of every course you recieve a certification for that level.
Closed Circuit Rebreather - All your exhalation is recycled in the system, none released into the water. Special training required.
Compressor - used for tankfills. filteres normal air and compress it in to you tank.
Cylinder - Tank that contains your compressed breathing gas.
Cramp - Normally in toes or legs. Possibly because of the exercise or too tight fins.
Contaminated air - Not clean pure air, usually prevented by using a reputable filling station.
Conditions - Referring to tha water: visibility, current, temperatures, thermocline e.t.c.
D
D-rings - Plastic or metal rings found on your equipment usually BCD, where you can attach extra equipment.
DAN - Divers Alert Network. A very reputable non-profit diving insurance.
DCS - Decompression sickness. when nitrogen bubles get stuck in your body.
DCI - Umbrella term that covers both decompression sickness and lungoverexpansion injuries.
Decompression stop - When you overstay your divelimits and cannot go straight to the surface.
Deep dive - Between 18m and 30m. 40m with special deep training.
Deflate - Referring to taking the air out of you BCD.
CESA - Controlled emergency swimming ascent. only used in the unlikely case you ran out of air, lost your buddy, but are still in shallow waters.
Descent rate - The time you take to go down to depth.
Diaphragm - Found in both second and first stages of the regulator.
DIN valve - Deutche industry norm. Where the regulator screws directly into the valve. Used in overhang environment and in cold water.
DPV - Diver propulsion vehicle. An underwater "scooter".
Dry suit - Isolates you from the water with a layer of air. used in cold water.
Dump valve - Safety features on your BCD to release excess air or quickly release the air.
Dust cap - Always on the regulator"entry" if not in use. protects for water or dirt coming in to the system.
E
EANx - Enriched Air Nitrox. When your breathing gas percentages differ from 21% Oxygen and 79% Nitrogen as in air allowing longer bottom times. Special training required.
Environmental protection - Found in the first stage if diving in cold environments, prevents the first stage to freeze up.
Equalization - Used to prevent pain and discomfort when air pockets are feeling pressure. Ears/sinusses/mask.
Equipment - Referring to all SCUBA equipment needed on the dive.
F
First stage - The first contact between the tank and your scubasystem.
G
Giant stride - A method used for entering the water of a boat.
H
Hydrostatic test - Performed by local law between every 3-7 years. the tank is filled with water and they check how much the metals expands.
Hyperbaric chamber - See recompression chamber.
I
Inflator button - The button that inflates you BCD.
J
J-valve - An old style of tank valve using a reserve tank system, rare to come by now though.
K
K-valve - The most common valve used, where the valve and the regulator fits on top of each other.
L
Lift bag - Used for lifting heavy objects out of the water.
Logbook - Where you write down your diveprofile and what you saw. A personal record of your diving
LPI - Low Pressure inflator. Used to control the air that goes in your BCD.
Lungoverexpansion Injuries - when the air expans your lungs so it ruptures. easily prevented by always breathing.
M
Mooring buoy/line - A line used for the boat to moor up on, so that they don't damage the reef by throwing anker.
Mouthpiece - The piece of the regulator that goes in your mouth.
N
Narced - Referring to nitrogen narcoses.
Negative buoyancy - When you sink.
Neoprene - The material used for wet suits.
Nitrogen narcosis - The intoxicating effect of nitrogen at depth. Usually around 30 m. or deeper.
Nitrox - EANX, Enriched air. With a different gas mixture than normal air. with 22-40% oxygen in the mix
NDL - No-decompression limit. The maximum dive limit for recreational divers. Where you don't do decompression stops.
O
O-ring - A rubber ring that secures a perfect seel between the air in your scubasystem and the surrounding water.
Open circuit - Normal scuba. Where you exhalation is directly released out in the water.
P
PADI - Professional Association of Divers International. The biggest dive organization in the world.
Partial Pressure - The effect of any part of components in the air.
Phosphorescence - The emission of light by bioluminescent plankton. seen on night dives.
Plancton - Small single celled organisms. Lives freely in the water.
Pony bottle - A small spare air bottle with own regulator.
Positive buoyancy - When you float upwards. Needed on the surface to reserve energy.
Purge button - In the center of your regulator. Gives you extra air to reject any water there might be in the regulator.
Q
Quick release - Usually referred to weightsystems. A quick single handed release.
R
Recompression chamber - Recompresses you after decompression sickness.
Recreational diving - Sports diving. No stop diving, Maximum depth after appropriate training is 40m.
Regulator - Commonly used to desccribe the entire regulator system which includes, at least, a first stage, primary second stage, alternate second stage, low-pressure inflator and air gauge.
S
SCUBA - Self-contained underwater breathing apparatus.
SMB - Surface marker buoy AKA safety sausage. Used for signalling the surface that there are divers below
SPG - Submersible pressure gauge. Measure your exact tank pressure.
Squeeze - When airpockets feel the water pressure and needs to be equalized. Usually ears, sinusses and mask is the ones affected.
Steel cylinder - Usually found in colder water. Steel corrodes faster in warm tropical water.
Surface interval - Time between repetitive dives.
T
Technical diving - Special training required. Exceeding recreational limits, decompression diving certain overhead environments.
Thermocline - When warm and cold water meet. Experienced as a sudden drop in temperature and/or visibility.
U
Unbalanced regulator - Increased breathing resistance with depth and emptying tank. Usually cheaper to buy and service because of less parts.
V
Valsalva manoeuvre - Equalizing method where you blow against a pinched nose.
Visibility - How far you can see horizontally under water.
Visual inspection - Done every year. the tank is checked on the inside and outside for corrosion or damage.
W
X
Y
Yoke - A common type of valve-regulator connection.
