Operation Manual

22
4 Functions during the dive
III UWATEC Aladin PRIME
4.5 Ascent rate
Optimal ascent rate varies depending on depth between 7 and 20m/min
(23 and 67ft/min). It is displayed as a percent of the reference variable ascent
rate. If the ascent rate is greater than 100% of the set value, the black arrow
"SLOW" appears. If the ascent rate exceeds 140%, the arrow starts flashing.
Aladin provides an audible alarm if the ascent rate is 110% or greater. The
intensity of the alarm increases in direct proportion to the degree that the
prescribed ascent rate is exceeded.
The prescribed ascent rate must be observed at all times! Exceeding the pre-
scribed ascent rate can lead to microbubbles in the arterial circulation which
can lead to serious injury or death due to decompression sickness.
• In case of an improper ascent Aladin may require a decompression stop even
within the no-stop phase because of the danger of microbubble formation.
• The decompression duration necessary for the prevention of microbubbles
can increase massively if the ascent rate is exceeded.
• From great depth a slow ascent may cause heightened saturation of tissues
and an extension of both decompression duration and total ascent time.
At shallow depth, a slow ascent may shorten the decompression duration.
• Display of the ascent rate has the priority over "CNS O
2
".
Reduce ascent rate
Excessive ascent rates for longer periods are entered in the logbook.
The following ascent rates correspond to the 100% value in Aladin.
Ascent rate Visual
alarm
Audible alarm
S
L
O
W
S
L
O
W
S
L
O
W
S
L
O
W
%
%
%
%
WARNING
WARNING
S
L
O
W
DEPTH
NO STOP
DIVE TIME
Ascent rate
depth (m) <6 <12 <18 <23 <27 <31 <35 <39 <44 <50 >50
speed (m/min) 7 8 9 10 11 13 15 17 18 19 20
depth (ft) <20 <40 <60 <75 <88 <101 <115 <128 <144 <164 >164
speed (ft/min) 23 26 29 33 36 43 49 56 59 62 66