Whether you are a new diver or a seasoned diver, it is always good to know the correct terms. Here is a list of the most common terms we use with their correct definition.
Terminology
1st Stage – The portion of your regulator which attaches to the tank. This first stage reduces the pressure from the tank to an interstage pressure. It is used to supply air to the second stage or to inflate your BCD.
2nd Stage – The portion of the regulator that takes your air pressure from intermediate pressure to breathable pressure. And is in your mouth to breathe your air as you need it.
A
Air – The normal air you breathe on the surface is the air you breathe underwater. It is 78% Nitrogen, 21% Oxygen, and 1% other gases.
Air 2 – A SCUBAPRO device that is basically a combination of an Octo and an Inflator.
B
Balanced Inflator – Device attached to BC used to inflate/default to adjust your buoyancy.
BC/BCD – Buoyancy Compensator Device. This device is what you use to adjust your buoyancy.
Boots – Dive shoes that you wear to protect your feet.
D
Dive Flag – A Flag designed to designate when divers are below the surface of the water.
Dive Master – The 1st step in becoming a dive professional leader. You can lead certified divers on dives.
Dive socks – Extra layer of insulation to be worn with dive boots. They also help in aiding in the donning of a wetsuit and dive boots.
Dry Suit – A dry suit is worn to keep the diver dry during a dive. Thermal underwear may be worn under the suit for added protection against the colder water elements.
F
Fins – A thin component or appendage that is worn on the foot. It is made of rubber or plastic or a combination of this material. It is to aid in the movement in water sports activities such as diving.
L
Lift Bag – An airtight bag with straps used to help move heavy items through the water.
M
Mask – Cover eye and nose to provide airspace so you can see underwater.
Master Diver – Accomplishment reached for a certified SCUBA diver. You have completed all the requirements specified by dive agency needed for this certification.
N
Nitrox – Mixture of Nitrogen and Oxygen used for breathing. Oxygen percentage is typically higher than regular air.
O
Octo – A secondary demand valve fitted with a first stage diving regulator. It is used as a backup source of air in for another diver in case of emergency.
Octo keeper – Keeps your Octo conveniently attached to your BC. Will be easily released if necessary.
P
Pony Bottle – A small container of air used as a backup air supply source.
Purge – Used to induce air flow to clear a valve of water or other substance.
Purge Valve – In a Mask as a way to clear water through gravity or exhalation.
R
Rash guard – A shirt made of Spandex, Nylon, or Polyester (or a mixture of) to protect the skin against rashes. These shirts can be worn by themselves or under a wetsuit.
Regulator – A mechanism used to move air from high pressure in the tank to the diver’s mouth so they can breathe underwater at ambient pressure.
S
Safety Sausage – Inflatable lift bag that floats upright in the water. They are brightly colored so it can easily be seen from the surface.
Save-a-Dive Kit – Kit containing items that could make easy repairs to your SCUBA equipment. Examples: Zip ties, O-rings, mouthpieces, extra straps, etc.
SCUBA – Self-Contained Underwater Breathing Apparatus.
Sea Snips – Scissors that will be used to cut entanglement. Should be easily accessible.
Skin – A Spandex suit worn in tropical water or under a wetsuit. If worn under a wetsuit, it helps diver put on their wetsuit.
Snorkel – A tube with a bend and a mouthpiece used for breathing air above the surface of the water.
Snorkel Keeper – A device used to hold the snorkel in place against the side of the mask strap.
T
Tank/Cylinder – Refillable compressed gas container that a diver straps to their back so they have air to breathe.
W
Wet Suit – Thermal insulated, foam neoprene suit that is close fitting, but allows a limited volume of water inside the suit for extra thermal insulation.