"10P's rule for
=
"17/45"
=
a Trimix of
"16 square" = "162" = "16/68" means a Trimix of
"AAS"
=
Alternate Air Source, see Bailout.
"ABLJ"
=
Adjustable Buoyacy Life Jacket, mostly build horse-collar style, much more than just a BC (Buoyancy Compensator).
"ADV"
=
Automatic Diluent Valve, see "Schraeder-Valve".
"AGE"
=
Arterial Gas Embolism, bubble causing obstruction to a blood vessel. The term Arterial Gas Embolism refers to small air bubbles in the bloodstream. This is almost always the result of a rapid ascent, with or without breath-holding, which causes the lung tissue to tear and allows air into the blood vessels.
"air hog"
=
Diver who sucks tank dry in record time. (Or in less time than it takes their buddy.)
"Ambient Pressure"
=
Pamb. = The pressure surrounding the diver/rebreather. Rough values are 1.0 bar at the surface, 2 bar at 10m, 3 bar at 20m, 4 bar at 30m etc.. When calibrating oxygen-sensors prior to diving, the ambient pressure is the current atmospheric pressure.
"APTDI"
=
"ATA"
=
"Axial flow scrubber"
=
A scrubber that is build like a pipe, where the gas flows from one to the other end of the pipe. The other concept is the "radial scrubber", in which the gas flows from the outer to the inner diameter.
"Best Mix"
=
The Breathing-Gas that offers the shortest Decompresson-Time. For Calculation you have to care about ED, END, ppO2-limits (ppO2-time-limits) and for extreme deep dives also about HPNS. In most cases the best mix for a OC bounce-dive is really not the best mix for a long rebreather dive to the same depth.
"Bailout"
=
An emergency breathing system: for example an extra cylinder of gas carried by a surface supplied diver or a rebreather diver to enable them to reach safety in the event of an interruption of their primary supply. For saturation divers, this would typically be to reach a habitat.
For a rebreather diver in most cases doing a bailout does not stand for a switch to an other breathing- system but just to an other mode, like moving from the CCR- to the SCR-mode on the same loop. But keep in mind: a loop could be unrecoverable, so take care of an alternative.
To bailout means ending the dive.
In doubt - bail out !
"BMAP"
=
B
uoyancy Mediated Airway Protection. This is an important matter for OC- and for Rebreather-Diver, so it has its own chapter. In my opinion a rebreather diver is only correctly equipped if he can start, with a single second of action, a process that will bring him to the surface, pull him in a face-up position and show a (not to small) signal-colour-surface. (That this can't work while being in a wreck or cave is no reason not to care about safety.) The result shall also be guaranteed if the main-bottle(s) of the rebreather are empty and the loop is partially or fully flooded."BOB"
=
Bailout Rebreather
"Braille dive"
=
Visibility so bad you have to just feel your way around 
"BT"
=
Bottom Time - definition is agency dependant.
"Calibration"
=
All the oxygen sensor-cells have to be calibrated before use.
"caustic cocktail"
=
for example what you get when you drown breathing lime by lots of water, NaOH is used as catalytic in the lime and washed out in the case of a flood. Ca(OH)2 plus Water also is a lye. Inhaling lye is dangerous, for first aid rebreather-divers carry Cortisone-Sprays like "Auxiloson".
"CCCR"
=
Chemically-Closed-Cirquit Rebreather
"CCR"
=
Closed Cirquit Rebreather
"Clusterflush"
=
purging the loop with diluent to establish a known fO2 when you have no idea what you're breathing - like when your electronics "salt fry".
"CMF"
=
Constant Mass Flow. The term "CMF-Nozzle" means the same as
"CNS Oxygen Toxicity"
=
Central Nervous System Oxygen Toxicity, also known as the Paul Bert Effect, tox, or oxtox. Oxygen toxicity is a combination of oxygen pressure and time. The exposure limits are shown on a separate page.
"Compression Arthralgia"
=
a symptom (some divers get it as 'shallow' as 70m) that shows by sounds in the joints, that your body in not really uncompressable. For more informations see books like "Bove, Diving Medicine".
"couch diving"
=
Wearing your rebreather while watching CNN in order to test out a new feature or method of operation.
"CPR"
=
Cardio-Pulmonary Rescusitation
"CSU"
=
ANDI Complete SafeAir® User = an initial OC-Nitrox Brevet
"cu. ft."
=
Cubic Feet. 1 cubic foot = 28.31685 liters. "80cu. ft." means 2265.348 bar*liter, so this tank for example has a volume of 10.74liters and is rated for a pressure of 211bar 
"cu. yd."
=
Cubic Yard. 1 yd = 3 ft = 0.9144 m -> 2.96 yd3 ~ 80 Cubic Feet ...
"DAU"
=
Dumbest Assumeable User or in German language
"DCI"
=
Decompression Illness, including DCS and AGE.
"DCS"
=
Decompression Sickness
Type I DCS: This is DCS that results in joint or muscle pain, extreme
fatigue or skin manifestations.
Type II DCS: Includes any DCS hit that has neurological or
cardio-respiratory symptoms.
"DDRC"
=
Diving Diseases Research Centre, in Plymouth, England. The leading hyperbaric treatment and research centre in Britain.
"DNAx"
=
Denitrogenated Air, means for the diver the same as EANx, but signalices that this Nitox was produced by using a nitrox-membrane (a system similar to osmotic sea-water desalting).
"DOA"
=
Dictionatry of Abbreviations. What you are reading at the moment is the
"DPV"
=
Dive Propulsion Vehicle = Scooter .
"drowned lime"
=
lime with water covering the active surface.
This can happen by flooding the canister or, as result of a poor rebreather-design, by condensation water .
"EAD"
=
Equivalent Air Depth (used on Nitrox-Dives to look into a Decompression-Table that was printed for Air-Dives.)
"EANx"
=
Enriched Air Nitrox, EAN40 contains 40% Oxygen and 60% Nitrogen.
"ECCR"
=
Electronically-Closed-Cirquit Rebreather
"ED"
=
Equivalent Density air (the depth in which Air brings the same breathing-resistance)
If someone does not care about the ED and dives a gas with too high density he risks an Esoufflement, what under diving-conditions normally also means Hypercapnia.
"END"
=
Equivalent Narcosis Depth (compares the narcotic potential of a gas with that of air)
This value may differ for the same gas if you read different authors, because some count Oxygen as not narcotic, some count it like Nitrogen and some double than nitrogen.
"end of the line"
=
Yet another caver term, used and abused by rebrether guys when talking about extreme rebreather diving.
"fiO2"
=
Fraction in the Inhaled gas that is Oxygen
"fsO2"
=
Fraction in the Supply gas that is Oxygen
"FSW"
=
Feet of Salt Water an antiquated, imperial unit of measurement for the depth or for relative pressure.
"Glue-Y's"
=
a resistor-devices that splits the wires form the O2-Sensors to the Displays. On the picture the green components symbolise the fuel-cell and the build-in temperature-compensation, the "Glue-Y's" are the pairs of red resistors. 
"goober-juice" or "lung-juice"
=
The disgusting slime that comes out of the hoses after a long dive.
"Halocline"
=
Boundary between layers of water of different salinities, looks like a barrier of mist.
"Hawaiian Method"
=
a method of in-water recompression (IWR).
"Heliox"
=
Breathing mix of Helium and Oxygen.
"Hogarth principle"
=
A name for the old principle that divers use since many decades: 'less is more'. It is named after
Your buddy is part of the Hogarth system, this means: strict team diving & uniform equipment constellation.
"Holistic system"
=
Teaching all subjects to all levels but more detailed to the more experanced. This means for example that also the Novice-Exam includes Medic-First-Aid.
"Hookah"
=
Regulator for breathing surface supplied air, either from a tank or a compressor, typically down to about 10m. Outside the Diving Community Hookah stands for Waterpipe.
"Hopcalite"
=
A Chemical used in Compressors for converting
"HPNS"
=
High Pressure Nerous Syndrom, a pressure, not Gas related effect that can happen on dives to more than 100m. Can be minimiced by slow descends plus using a little bit Nitrogen (N2) in the breathing mix.
"HUD"
=
Heads Up Display: at mimium 3multicolor-LED's you can see by looking up (HUD lights), at maximum a computer-screen mirrored into your mask as message center.
"Hypercapnia"
=
An excess of carbon dioxide.
"Hyperoxic"
=
Used by some folks when they just mean Situations with a ppO2 above 1.6 bar.
"Hypoxic"
=
When the ppO2 is less than 0.16 bar.
"in the loop"
=
Knowing or learning something related to the discussion at hand.
"IP"
=
Intermediate Pressure, also named LP, i.e. the pressure between the first and second stages.
"Jackadd"
=
JACK-ADD = Added Jack = BC-Device that is an add-on of Tank or Rebreather and does not offer all ABLJ safety-functions.
"keyboard diver"
=
Term for those who spend much more time typing about diving than actually doing it.
"Kramer-Valve"
=
A rebreather-valve that allows hands-free buoyancy control and several safety functions. Could be called a
"lbs"
=
1 pound (lb) = 16 ounces (oz) = 453,59g
- Ounce avoirdupois (oz or oz avdp): 8 drams, 437,5 grains: 28,350g
(the normal Weight Ounce) - Ounce troy (oz t) (the Gold Ounce): 20 pennyweight, 480 grains: 31,103g
- US Fluid ounce (fl): 8 fluidrams: 29,573 ml
(a Standard for Beverages) - UK Fluid ounce (fl): 8 fluidrams: 28,412 ml
"Lime"
=
mostly CO2 absorbtion is done by "breathing lime". Chemically this is
H2CO3
Na2CO3 + 2H2O
CaCO3 + 2NaOH
when written down without the catalytic part the formular becomes
CaCO3 + H2O
"Limeburger"
=
Diver between Rebreather and Bailout-Rebreather
"Limey"
=
A Buddy Inspiration Owner
"Liorraine Smith Effect"
=
"LP"
=
Low Pressure, also named IP, i.e. the pressure between the first and
"Lubrication"
=
(if used by rebreather divers it means) any approved oxygen compatible grease.
"MOD"
=
Maximum Operating Depth for a breathing gas in the given situation.
"Nagileh System"
=
"Hookah"
"Naszogen"
=
chemical gas generator
"NDL"
=
Non Decompression Limit = the time you can dive on a given depth, breathing a given gas without the need of a decompression-stop = "Nullzeit"
"NITROX"
=
Breathing mix of Nitrogen and Oxygen.
"NITROX-pure"
=
the Trademark under which the Messer Griesheim GmbH sells their diving-grade EANx.
"no bubbles, no troubles"
=
after the dip check, everything's ready to go diving.
"O2 clean"
=
Clean enough of combustibles such as oil to allow use with high pressure O2.
"O-3"
=
A trademark for a chemical used in chemical-nitrox-rebreathers like the IDA-71. Unlike breathing-lime, it produces O2 when it eats CO2.
"OC"
=
Open-Circuit mode, that meas that the gas is exhaled to the environment, not into a rebreather.
"on bag, off bag"
=
the points in time where one begins or stops breathing from the loop.
"OTU"
=
pulmonary Oxygen Toxicity Unit. Oxygen toxicity is a combination of oxygen pressure and time. The exposure limits are shown on a separate page.
"Oxy Gauge"
=
a meter that displays your loop-ppO2. You can use it to test your mix and to know your ppO2 under water. My recommondation is to dive every SCR and CCCR with something like a Oxy Gauge or a Divecomputer with ppO2-Sensor.
"Oxygen Cells"
=
Cells or Sensors used to monitor the ppO2.
"P-vent"
=
Directing the vented bubbles on ascent up the neck of your wetsuit while in a heads-down position for the purpose of removing urine.
"Pamb."
=
Ambient Pressure = The pressure surrounding the diver/rebreather. Rough value are 1.0 bar at the surface, 2 bar at 10m, 3 bar at 20m, 4 bar at 30m etc.. When calibrating oxygen-sensors prior to diving, the ambient pressure is the current atmospheric pressure.
"Paul Bert Effect"
=
"Phallocline"
=
the boundary layer between "really cold!!" deep water and relatively warm surface water, the zone where your dick disappears somewhere behind your bellybutton
"Pony Bottle"
=
a small (i.e. 4Liter*200bar) tank, typically worn beside main tank/rebreather, as a fully redundant emergency air supply.
"PP diver"
=
Personal Preference diver. A Cavediver Term for someone who does not dive in the usual (the best) Configuration.
"ppO2"
=
Partial Pressure of Oxygen. Some write PO2 or PPO2 instead, but what looks like chemistry formulas.
"psi"
=
Pounds per Square Inch, 14.50377psi = 1bar.
"RMV"
=
Respiratory Minute Volume
= (in Germany) "AMV"
The RMV is measured in Liter per Minute, so a OC-SCUBA-Diver who is diving in depth of 30m would empty his bottles with 100 bar*l/min while breathing with an RMV of 25 l/min.
You should use RMV, not SAC, in diving matters, in order to preserve
Misunderstandings when Air is not the Gas which is breathed.
"ROV"
=
Remote operated Vehicle.
"Rule #1"
=
NEVER dive alone !
"Don't dive with strokes" means pretty the same, as a bad companion is even worse than being alone.
"Rule of Thirds"
=
effective breathing-gas: a third to get there, a third to get back and a third is for safety.
"SAC"
=
Surface 'Air' Consumption, see "RMV".
"SafeAir"
=
a markterm invented by Ed Betts, president of the ANDI training agency. SafeAir® is an EAN mixture between 22 and 50% Oxygen that meets ANDI gas quality specifications.
"Schraeder-Valve"
=
a mechanically-actuated (spring-loaded) valve on the inhale-counterlung. When the counterlung bottoms-out, the valve is actuated, and diluent is added to the loop until the counterlung is no-longer bottomed-out. Most people "ride" the loop volume such that, during full inhalation, it does not have much gas in the counterlungs. In that circumstance, without that valve you get less-than-full inhalation with only a feet of descent (without automatic addition), and you get "coke bottle" with only about 3m or so (in the 10m depth range - obviously, the deeper you go, the more range you have). For engineering models some constructors used Sherwood Brute or -Octopus regulators for those demand adds because they are cheap, easy to install in different housings due to the simple valve design, and it's easy to adjust them so that you really have to suck to get any air.
"SCR"
=
Semi-Closed Rebreather
"scrubber"
=
where the CO2 is removed = the lime canister. Means the complete canister used for CO2 removal and may also be the housing for, and so include, oxygen analysis and oxygen addition components. If the scrubber contains more than the breathing-lime, the word cartridge is in use for the lime container that is inserted into the scrubber.
"Scamahorn-Slide"
=
When you descend, diving an ECCR you have the problem that adding Diluent increases your ppO2 (because the Dil. should always be breathable). Taking care of this by running a lower Setpoint is named Scamahorn-Slide, but it seems it was invented by
It should be rightfully called "Juergensen-Slide" or the "Dude-Slide-Into-The-Great-Abyss".
"SCUBA"
=
any type of Self Contained Underwater Breathing Apparatus, this includes Rebreathers as well as OC-Air-SCUBA.
"SEEDS"
=
The Responsibilities of the Diveleader:
- Safety
- Equipment
- Exercise
- Discipline
- Signals
"Setpoint"
=
The pre-selected setting about which the oxygen controller attempts to maintain the actual ppO2 in the breathing loop of a CCR.
"Shot line"
=
a weight with line and buoy attached to mark the location of a wreck.
"SI"
=
Surface Interval (between dives)
"Sling [Bottle]"
=
Stage Bottle
"Slobwinder"
=
a flexible shaft, used to open/close valves that can't be reached directly. It might be a better idea to confiure und train so that everything can be reached.
"Stroke"
=
Favorite term of Florida cavers which is applied to anybody who dives without proper knowledge or intelligence.
"SMB"
=
Surface Marker Buoy. Buoy with flag (on a line to diver).
"Sofonolime"
=
A trademark for absorbent used in the scrubber to remove CO2 from the exhaled gases.
"Spherasorb"
=
A trademark, used by Intersurgical for their absorbent in the scrubber that removes CO2 from the exhaled gases.
"Stage Bottle"
=
a separate gas supply which is detachable from the diver.
"sucking and blowing"
=
the start of a CO2 buildup, and the beginning of a really bad dive.
"suction device"
=
the diver
"Regardless of the type of controls, the biggest factor in rebreather safety
is still the suction device attached to the mouthpiece."
"Suckstarting"
=
pre-breathing the absorbent to get the reaction going. Roughly 10°C more lime temperature double the reaction speed. Performing a "5-minute" pre-breathing is a matter of safety. When perfoming a Suckstart, you have to think about getting into a sweat.
"tamping one's canister"
=
well, I'm sorry, maybe that one was a little mean.
"Thermocline"
=
the boundary between layers of water of different temperatures.
"TIC"
=
Tank Integated Counterweighting or in our context
"TLF"
=
Total Loop Failure
"TMC"
=
Tank Mounted Counterweighting or in our context
"top-to-bottom vis"
=
Underwater visibility so good you can see the wreck from the surface.
"Trimix"
=
Trimix mostly is (in the Matter of Diving) understood as Breathing-Mix of Oxygen + Nitrogen + Helium, which is dedicated be breathed at depths that are too deep to be reached with Air or Nitrox. Mostly Trimix is produced by enriching Air or Nitrox with Helium.
- "HeliAir" is such a "Deeper-Dive Trimix". 10/50 means 50%Helium, Rest Air (and so abt. 10% Oxygen).
- "Normoxic Trimix" is NOT what normally is meant when Divers (hopefully not when Governments) are speaking about Trimix, as it contains about the same Oxygen Fraction as Air and so does not apply as Breatinggas at depths that are out of Range for Air.
- "TriOx" is really NOT what normally is meant when Divers (hopefully also not when Governments) are speaking about Trimix, as it contains an Oxygen Fraction of 21% or more. A typical TriOx for Example is 40%Oxygen + 34%Helium + 26%Nitrogen. Triox40 has the same MOD as Nitrox40, but all the advantages of a lower Nitrogen Fraction.
"Turtle"
=
often a Nickname that means Rebreather.
"VENT ID"
=
Vent It ( = do a clusterflush): what you have to do with a Rebreather- Loop in the case of the Central Nervous System (CNS)
CNS-Tox Symptoms are:
- Visual (focus, tunnel, spotty etc.)
- Ears (ringing, abnormal)
- Nausea (spastic vomiting)
- Twiching (facial)
- Irritability
- Dizziness
"WOB"
=
Work Of Breath, the engery you need to breath a given volume of gas.
"warm fuzzies"
=
that feeling when you know that you have many hours of breathing gas on your back.
"XBS"
=
External Breathing System = BOB (but someone also might mean a Stage)
"YANQ"
=
Yet another Newbee Question. Ok, this is not rebreather-specific and never forget:
Rebreather-Index