Instruction Manual

5
• PART I
• 1. INTRODUCTION
1.1. GLOSSARY
AIR: Air dive
AVG: Average depth, calculated from the beginning of the dive.
CNS: Central Nervous System. CNS% is used to quantify toxic effects of oxygen.
D-TIME: Dive time, the whole time spent below a depth of 1.2m/4ft.
DESAT: Desaturation time. The time needed for the body to eliminate the nitrogen taken up during diving.
Gas integration: The feature in Sirius to include tank pressure information in its calculations and to display it on the computer screen.
Gas switching: The act of changing from one breathing gas to another.
GF: Gradient factor
Gradient Factor: Reduction of Bühlmann’s original value of maximum tolerated inert gas pressure.
Heliox: A breathing gas containing Oxygen and Helium.
Max depth: Maximum depth attained during the dive.
MOD:
Maximum Operating Depth. This is the depth at which the partial pressure of oxygen (ppO
2
) reaches the maximum allowed
level (ppO
2
max). Diving deeper than the MOD will expose the diver to unsafe ppO
2
levels.
Multigas: Refers to a dive in which more than one breathing gas is used.
Nitrox: A breathing mix made of oxygen and nitrogen, with the oxygen concentration being 22% or higher.
No deco time:
This is the time that you can stay at the current depth and still make a direct ascent to the surface without having to perform
mandatory decompression stops.
NO-FLY: Minimum amount of time the diver should wait before taking a plane.
O
2
: Oxygen.
O
2
%: Oxygen concentration used by the computer in all calculations.
Pairing: The act of establishing a coded RF communication between Sirius and a dedicated device, such as a tank module.
ppO
2
:
Partial pressure of oxygen. This is the pressure of the oxygen in the breathing mix. It is a function of depth and oxygen
concentration. A ppO
2
higher than 1.6bar is considered dangerous.
ppO
2
max: The maximum allowed value for ppO
2
. Together with the oxygen concentration it defines the MOD.
S. I.: Surface interval, the time that has elapsed since the end of the dive.
Switch depth: The depth at which the diver plans to switch to a higher oxygen concentration mix while using the multigas option.
TOD: Time Of Day
TTR: Time To Reserve, it is the time that a diver can spend at the current depth before reaching the tank reserve.
TTS:
Time To Surface, the time it takes to perform the ascent from your current depth to the surface in a decompression dive,
including all decompression stops and assuming an ascent rate of 10m/min or 33ft/min.
TTS @+X: The overall ascent time inclusive of all decompression stops if the dive is extended by X minutes at the current depth.