Emergency Ascents
In the unlikely event that the
IQ-400
malfunctions during a dive, follow the
emergency procedures provided by your certified dive training agency or, alter-
natively, immediately ascend at a rate slower than 10 m/min [33 ft/min] to a
depth between 3 and 6 meters [10 to 20 ft] and stay there as long as your air
supply will safely allow.
Higher Risk Dive Profiles
The user must understand that all decompression devices (decompression
tables and/or dive computers) are based on mathematical models and that
many experts are currently concerned that these models may not under certain
conditions adequately describe the physiological phenomena. These conditions
are presently identified as dives which incorporate the following (Fig. 1.1):
Sawtooth Profiles
where the diver alternates between greater and shal-
lower depths repeatedly throughout the dive.
Reverse Profiles
where the diver spends most of the dive at shallow
depths and then descends to the maximum depth
shortly before surfacing.
Consecutive Dives
where the diver performs repetitive dives to approxi-
mately the same maximum depth with only short
surface intervals between dives. The risk of decom-
pression sickness increases when depth and the num-
ber of repetitive dives increase and when the surface
intervals are decreased.
Multiday Dives
repetitive dives performed for several consecutive
days.
Decompression Dives
any dive during which the no-decompression limit
has been exceeded or the diver is advised by the com-
puter that he may not return directly to the surface.
8
depth
time
Sawtooth profiles
depth
time
Reverse profiles
depth
time
Consecutive dives
Multiday dives
Figure 1.1 Higher Risk Profiles
