Equipment My first out of air situation

[scubadada]

Hi @ispasov

Don't you think someone would have seen something if you had catastrophic gas loss for a short period?

 

[ispasov]

What's bothering me is the bubbles I was hearing while adjusting my trim. What could be affected by changes of body position while diving?

 

[JMarc]

He offered me his backup 2nd stage, but I didn't take it immediately, because I was still breathing (harder and harder, but still doable). We slowly started going up. I positioned myself very close to his octo, so that in case I run out of air completely I can grab it relatively quickly.

This aspect seems to have been neglected by others. It is in my opinion an error not to take the octopus immediately in a low air situation. Why? If you are waiting for your tank to be completely empty to switch to a buddy octopus and then you have no reserve to switch back to your tank should an emergency happens.

(Same as others, I'd probably have skipped the safety stop in this situation, but that's more for the DM than for you)

A note: depending on the regulator internals, the transition from easy to breath to hard to breath can be more or less sudden.

 

[davehicks]

Not possible either. If this was the cause once they started ascending his flow would have resumed but according to his description the DM tried the OPs first stage during the safety stop and it delivered no gas. The pressure graph would also show this (pressure would fluctuate for every breath up and down) .

Maybe, but he also kept breathing down the tank. Unless they checked, i say this is likely.

 

[stepfen]

What's bothering me is the bubbles I was hearing while adjusting my trim. What could be affected by changes of body position while diving?

That can be water in the BCD . Nothing to worry about. The gas you "lost" was about 100bars *11 lt (assuming the usual 11lt AL tank was used) = ~1100lt . You can't loose that much gas within minutes without noticing (huge amount of bubbles, noise etc)

 

[ispasov]

Since we were using DIN regulators, is it possible for the o-ring to have fallen during the setup process without me noticing? I can't remember if it was on the reg when I disassembled my gear.

 

[ispasov]

@ispasov

Did you own any of the gear you were using? If so which was yours, and which was rented?

Almost all of the gear was mine own. I was only renting the regulators and the tank. My BC was brand new and that was my 3rd dive with it.

 

[JMarc]

Since we were using DIN regulators, is it possible for the o-ring to have fallen during the setup process without me noticing? I can't remember if it was on the reg when I disassembled my gear.

A missing o-ring would have been noticed by everybody around when you opened the tank.

 

[stepfen]

Since we were using DIN regulators, is it possible for the o-ring to have fallen during the setup process without me noticing? I can't remember if it was on the reg when I disassembled my gear.

It is possible to screw the DIN regulator in without the oring, but you would have noticed it immediately upon opening the valve as huge amount of gas would leak. You can't start a dive without that oring.

 

[Still Kicking]

You said that you looked at your computer and found you were almost out of air. By this, I assume you are diving with an air integrated computer. You should set your computer to give you a warning when you reach a conservative reserve pressure (set a pressure you feel comfortable with). In this way the computer will mind your gas consumption if you get distracted in the future.

Otherwise, good job handling a stressful situation. I agree you should abbreviate or skip the safety stop if you run extremely low on air again.