[underwater exhalation]
At NOAA, when doing working dives or in situations with limited visibility, overhead environments, or where you can be separated
from you dive buddy, divers are required to carry a redundant air supply system.
At NOAA, we call this a RASS.
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.
The video we are about to see is RASS to the surface.
So here a diver has run out of air and there's been a buddy separation,
so the diver must make it to the surface.
Here the diver has run out of air...
Now, here we find a "known". We know the bottom of the cylinder.
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.
Later on if you go to do decompression diving you might be wearing a sling bottle on the side.
This might be required decompression gas.
Or you might have a ceiling or overhead stops required.
So we start habits here.
Find the bottom of the cylinder. From the bottom of the cylinder you can find the second stage.
From the second stage you can find the on/off valve.
From the on/off valve you know we are at the first stage, from the first stage you can find the pressure gauge.
so from one known location you can find all the components on the pony bottle. So let's watch all those steps.
From a known, to the on/off valve, from the on/off valve, to the second stage,
purge it,
put it in your mouth and breathe from it.
any time a diver
doesn't have a second stage in their mouth they need to be blowing a steady stream of bubbles.
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.
Here we are adding 2 to 3 breaths to the BC
and you're catching that air inside your BC. This is going to make your ascent much easier.
That air that you've captured inside your BC is going to expand on your way to the surface.
Hand positions. Here we have the right hand with a closed fist above our head. A closed fist protects your fingers.
A closed fist also protects your head from overhead obstructions.
your left hand holds the BCD inflator/deflator at the highest point above your left shoulder.
A couple reasons for doing this: as you're ascending to the surface the air trapped inside your BC
is going to expand. You may need to vent some air from your BC to slow down your ascent.
also when you get to the surface
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.
That's the alternate air source inflator or the second stage located in your left hand.
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.
Still, when the diver gets to the surface go ahead and take the second stage out and you take breaths from ambient air
and you blow that air into your BC.
Once you are at the surface, go ahead and ditch the second stage
taking big breaths from ambient air and pushing the yellow button directly in front of the mouthpiece with your two fingers.
Only blow when you're pushing the button, that will capture air inside your BC.
The skill is over when the diver is positively buoyant.