User's Manual

Suunto EON Steel
User guide
39(40)
and returning to the surface at the end of a dive.
Floor
The deepest depth during a decompression stop dive
at which decompression takes place.
He%
Helium percentage or helium fraction in the breathing
gas.
MOD
Maximum operating depth of a breathing gas is the
depth at which the partial pressure of oxygen (pO2) of
the gas mix exceeds a safe limit.
Multi level dive
A single or repetitive dive that includes time spent at
various depths and whose no decompression limits are
therefore not determined solely by the maximum depth
attained.
Nitrox (Nx)
In sports diving, refers to any mix with a higher fraction
of oxygen than standard air.
No deco
(No decompression
stop time)
The maximum amount of time a diver may remain at a
particular depth without having to make decompression
stops during the subsequent ascent.
No decompression
dive
Any dive which permits a direct, uninterrupted ascent
to the surface at any time.
No dec time
Abbreviation for no decompression time limit.
OC
Open-circuit. Scuba that exhausts all exhaled gas.
OTU
Oxygen tolerance unit. Used to measure the whole-
body-toxicity, caused by prolonged exposure to high
oxygen partial pressures. The most common symptoms
are irritation in the lungs, a burning sensation in the
chest, coughing and reduction of the vital capacity.
O2%
Oxygen percentage or oxygen fraction in the breathing
gas. Standard air has 21% oxygen.
Partial pressure of
oxygen (pO2)
Limits the maximum depth to which the nitrox mixture
can be safely used. The maximum partial pressure limit
for enriched air diving is 1.4 bar. The contingency
partial pressure limit is 1.6 bar. Dives beyond this limit
risk immediate oxygen toxicity.
Reduced gradient
bubble model
(RGBM)
Modern algorithm for tracking both dissolved and free
gas in divers.
Repetitive dive
Any dive whose decompression time limits are affected