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Utility Navigation

Controlled Ascent

Oct 21

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Transcript Content


00:00:05.000 --> 00:00:07.000
[underwater exhalation]

00:00:11.566 --> 00:00:15.366
Your bottom time ends when you start to make a
direct ascent to the surface.

00:00:15.366 --> 00:00:23.066
It's important that you're able to control your
ascent because dive tables are based on an
ascent rate of no faster than 30 feet per minute.

00:00:23.066 --> 00:00:26.266
There are a few things you need to adjust in
order to moderate your ascent.

00:00:26.266 --> 00:00:29.432
For example, the air inside your BC starts to

00:00:29.433 --> 00:00:33.633
Also gas trapped in your exposure protection
will expand and increase your ascent rate.

00:00:33.900 --> 00:00:39.066
You need to stay with your dive buddies and
everyone in the group should ascend at the
same rate.

00:00:40.900 --> 00:00:44.500
Before you make a controlled ascent there are a
few things you need to do.

00:00:44.500 --> 00:00:48.100
Check with your dive buddies and make sure
they are ready to leave bottom.

00:00:48.100 --> 00:00:53.166
check your cylinder pressure and then check
your dive time so you know when your dive ends.

00:00:53.166 --> 00:00:56.632
Hand positions are very important during a
controlled ascent.

00:00:56.633 --> 00:01:01.599
All divers should always have their right hand
with a closed fist above their head.

00:01:01.600 --> 00:01:03.700
The closed fist protects your fingers.

00:01:04.200 --> 00:01:07.600
The fist above your head protects your head
from overhead obstructions.

00:01:08.666 --> 00:01:12.932
All divers always look above themselves and
their dive buddies for overhead obstructions

00:01:12.933 --> 00:01:16.033
and we can only ascend as fast as the slowest
diver in the buddy team.

00:01:30.833 --> 00:01:37.666
When the divers get to the surface, the first thing
they do is inflate their BCs so that they're
positively buoyant.

Closed Caption File




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