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Reserve Air Supply System (RASS) to the Surface

Oct 21

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

00:00:11.466 --> 00:00:17.599
At NOAA, when doing working dives or in
situations with limited visibility, overhead
environments, or where you can be separated

00:00:17.600 --> 00:00:23.033
from you dive buddy, divers are required to
carry a redundant air supply system.

00:00:23.033 --> 00:00:25.799
At NOAA, we call this a RASS.

00:00:25.800 --> 00:00:32.566
Ideally, all divers on all dives should be self-
sufficient and carry a RASS. You'll be happy you
had one if you ever run out of air.

00:00:34.033 --> 00:00:36.466
The video we are about to see is RASS to the

00:00:36.466 --> 00:00:40.432
So here a diver has run out of air and there's
been a buddy separation,

00:00:40.433 --> 00:00:42.766
so the diver must make it to the surface.

00:00:42.766 --> 00:00:44.932
Here the diver has run out of air...

00:00:44.966 --> 00:00:48.866
Now, here we find a "known". We know the
bottom of the cylinder.

00:00:48.866 --> 00:00:57.332
Once you find the bottom of the cylinder you
can find the rest of the components. So this is a
habit we're starting early on in all divers.

00:00:57.333 --> 00:01:00.966
Later on if you go to do decompression diving
you might be wearing a sling bottle on the side.

00:01:00.966 --> 00:01:04.166
This might be required decompression gas.

00:01:04.166 --> 00:01:07.499
Or you might have a ceiling or overhead stops

00:01:08.100 --> 00:01:09.566
So we start habits here.

00:01:09.566 --> 00:01:15.466
Find the bottom of the cylinder. From the bottom
of the cylinder you can find the second stage.

00:01:15.466 --> 00:01:18.466
From the second stage you can find the on/off

00:01:18.466 --> 00:01:22.732
From the on/off valve you know we are at the
first stage, from the first stage you can find the
pressure gauge.

00:01:22.733 --> 00:01:29.266
so from one known location you can find all the
components on the pony bottle. So let's watch
all those steps.

00:01:29.266 --> 00:01:34.032
From a known, to the on/off valve, from the
on/off valve, to the second stage,

00:01:34.033 --> 00:01:35.466
purge it,

00:01:35.466 --> 00:01:37.632
put it in your mouth and breathe from it.

00:01:37.633 --> 00:01:39.599
any time a diver

00:01:39.600 --> 00:01:45.100
doesn't have a second stage in their mouth they
need to be blowing a steady stream of bubbles.

00:01:45.100 --> 00:01:54.500
So even in between the second stage and orally
inflating the BC there's still a steady stream of
bubbles coming out of the diver's mouth.

00:01:54.500 --> 00:01:58.500
Here we are adding 2 to 3 breaths to the BC

00:01:58.500 --> 00:02:03.066
and you're catching that air inside your BC. This
is going to make your ascent much easier.

00:02:03.066 --> 00:02:07.666
That air that you've captured inside your BC is
going to expand on your way to the surface.

00:02:07.666 --> 00:02:15.666
Hand positions. Here we have the right hand
with a closed fist above our head. A closed fist
protects your fingers.

00:02:15.666 --> 00:02:19.866
A closed fist also protects your head from
overhead obstructions.

00:02:19.866 --> 00:02:26.399
your left hand holds the BCD inflator/deflator at
the highest point above your left shoulder.

00:02:26.400 --> 00:02:31.600
A couple reasons for doing this: as you're
ascending to the surface the air trapped inside
your BC

00:02:31.600 --> 00:02:36.833
is going to expand. You may need to vent some
air from your BC to slow down your ascent.

00:02:36.833 --> 00:02:38.833
also when you get to the surface

00:02:38.833 --> 00:02:45.499
you have to orally inflate your BC, so when you
get to the surface you've already located the
thing you have to blow air into.

00:02:45.500 --> 00:02:52.166
That's the alternate air source inflator or the
second stage located in your left hand.

00:02:52.166 --> 00:03:00.699
Here you see as the diver ascends to the
surface, less and less effort is required. The air
trapped in the BC is starting to take over.

00:03:00.700 --> 00:03:07.233
Still, when the diver gets to the surface go
ahead and take the second stage out and you
take breaths from ambient air

00:03:07.233 --> 00:03:11.499
and you blow that air into your BC.

00:03:14.433 --> 00:03:18.199
Once you are at the surface, go ahead and
ditch the second stage

00:03:18.200 --> 00:03:24.666
taking big breaths from ambient air and pushing
the yellow button directly in front of the
mouthpiece with your two fingers.

00:03:24.666 --> 00:03:30.432
Only blow when you're pushing the button, that
will capture air inside your BC.

00:03:30.433 --> 00:03:32.633
The skill is over when the diver is positively

Closed Caption File




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