GLOSSARY
Altitude dive
A dive made at an elevation greater than 300 m/1000 ft above sea level.
Ascent rate
The speed at which the diver ascends toward the surface.
ASC RATE
Abbreviation for ascent rate.
Ascent time
The minimum amount of time needed to reach the surface on a decom-
pression stop dive.
ASC TIME
Abbreviation for ascent time.
CCR
Closed-Circuit Rebreather; scuba that recycles all exhaled gas.
Ceiling
On a decompression stop dive, the shallowest depth to which a diver may
ascend based on computed nitrogen load.
Ceiling zone
On a decompression stop dive, the zone between the ceiling and the
ceiling plus 1.2 m/4 ft. This depth range is displayed with two arrows
pointing toward each other (the ”hour glass” icon).
Central nervous system toxicity
Toxicity caused by oxygen. Can cause a variety of neurological symptoms.
The most important of which is an epileptic-like convulsion which can
cause a diver to drown.
CNS
Abbreviation for central nervous system toxicity.
CNS%
Central nervous system toxicity limit fraction. Also note Oxygen Limit
Fraction
Compartment
See "Tissue group".
DAN
Abbreviation for Divers Alert Network.
DCS
Abbreviation for decompression sickness.
DM4
Suunto DM4 with Movescount, a software for managing your dives
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