22
4 Functions during the dive
III UWATEC
®
Aladin
®
dive computers
4.6 Ascent rate
Optimal ascent rate varies depending on depth between 7 and 20 m/min (23
and 67 ft/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 pre-
scribed 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
>.
Excessive ascent rates for longer periods are entered in the logbook.
Ascent rate Visual
alarm
Audible alarm