No Air @ 5

[Harlequin]

I was going to post this anonymously but decided not to and have taken names out as other parties were involved but I learnt some valuable lessons which I'm hoping others will take on board.

Why do we surface with 50 Bar...? Well...

Let me set the scene…

The sun’s out, the water’s gin clear and the diving’s looking good. We did the dive and although we became a little lost it wasn’t an issue as finding a familiar spot on this site wasn’t too difficult but it did take us a few minutes, so understandably air was becoming an issue... 33 minutes into the dive I had 100 bar left at 25m, not an issue and my buddy had the same. However, a gentle current started and before I knew it I was down to 50 bar and my buddy was way off ahead. Now I did try to get his attention but he, like all of us, was becoming a little more concerned with ascending so I decided to buddy up with another pair and informed them I was low on air but that I would continue (my first mistake).

Spread across about 20 metres the guide signalled to my buddy who in turn signalled to me that the anchor was in sight (that's 20 metres away and at about 20m depth), bar...? 30...! OK I thought, no problems, I can make an ascent on that and still do my stop (my 2nd mistake).

On arriving at the bar for some strange anal reason I checked my gauge (I always do this) and noticed it was reading 5 bar. I was as shocked as my buddy when I turned it to him to show him. I carried on breathing until I basically drew just half a breath.

Now, here’s when I started thinking things like… OK, I can just pop up… But hold on Mick… didn’t you just do a dive this morning that put you into deco and then back out on the way up…? Oh, and didn’t you clock up an extra minute’s stop on this dive before clearing it on the way up…? Mmmm… Nope, I’ll grab some air me thinks…! So, I signalled (yeah, incorrectly) that I wanted air, but I forgot to preceed this with “Out of Air”. My buddy very kindly gave me his primary and as I saw him put mine in his mouth I took a long breath, pulled his reg out and shook my head “No air in that mate” and handed his reg back while I grappled for his octopus. Just one minor issue though, well 2 actually…

1. His octo’s hose was trapped under a reel so although I could get air I had me head stuck under his armpit. Fun eh…?
2. He was probably quite low by now as his main reg freeflowed while we were beathing off it.

Another diver came along about a minute into this fiasco and I simply saw a nice lurvely looking yellow octopus in front of me so grabbed it and stuffed it in me gob.

3 minutes later made a concerted effort not to bolt for the surface and we all got back on the boat.

On reflection…

1. Never again will I ascend with so little in my tank as it really brought home to me how inaccurate gauges can be.
2. If I do, and hopefully will not, but if I do run out of air then I’ll give the proper signal.
3. I could very easily have caused some serious damage to myself or my buddy.

By The Way…

Tanks do give a breath when they’re dry… Only half a breath mind, but a breath all the same

[MRBLUESKY]

Thanks for posting this Harlequin.

I often dive below the recommended "50 bar on the boat" limit, and sometimes wonder if I am taking a bigger risk than I should. Maybe this story will come to mind next time I am considering doing it.

I should point out that I only drop below 50bar when I am within the last 5 to 10 metres and well on my way up, and only to allow a little extra time off-gassing in the shallows. Also I never go into deco and try to maintain non-agressive profiles.

All of that said I will take this post as a reminder of what can happen.

Cheers

Andy

[TerryH]

Which sorta comes onto another no-no.

Gauges can be 10% out.
You need at least 10 bar to be able to inflate a BC/drysuit on the surface.
So the very least you need in a cylinder is 20 bar.

So why do some twinsetted divers think its ok to have that 50 bar as 25 bar
across 2 cylinders on the second so-called shallow dive?

Even if you did manage a shutdown, that's only 25 bar left and chances
are that you would have less than that.

50 bar is not THE reserve it's A reserve.

Whatever the dive, you should calculate worse case at the FUBAR moment
which is just before the ascent. Very lazy to depend on the red line without
actually doing the calcs.

.

[Hazel W]

basically as I understand it ....and the way I have dived (with a few notable exceptions ) is that the 50 bar is not there to inflate anything at the surface ..... there is a whole world of air up there ....its to allow for "deep doo doo" moments on the ascent when the entire world goes to s*** and you need to bring you and your buddy up on a single rig.

well posted Harlequin



Another vote for get you out the poo backup gas supply .....dont leave home without one !

Hazel

[David]

Originally Posted by MRBLUESKY

Thanks for posting this Harlequin.

I often dive below the recommended "50 bar on the boat" limit
Andy

in nice warm waters sucking till my reg free flows at about 10 bar is not un heard of, but only when on a reef and in inches of water well maybe a few meters :-)

but not in the uk its a kind of madness but Harlequin report is good and just shows it was not the first problem that caused him any worry would I of done the same, dont know but I can see how it happend and think its cool these reports are written without them how could we improve our diveing.

David

[Reikimaster]

fair play to you for posting, the fact that you have tells me that you have learned the lesson (the hard way)

Personally i would never breath a cylinder until it stops giving air (unless i had been seperated and it was the only air i had) and have always concidered 50bar to be an out of air call then end the dive if at depth.

Call the out of air early, while you still have some, then if there is an issue you have time to resolve it. Also an accent to 6m on an oct then switch back to your own for the stop makes it easier to hold your stop and then get back on the boat with your reg still in if there are engine fumes kicking around (more a uk thing than blue water, and i think you mentioned an ancor line so not relevant.)

As for you comment about 25bar in set of twins,
hmm
100 bar in twin 12's (which is what a twinset should be at after a first dive) is the same volume of gas a 200bar in a single 12. so is plenty for a 15-20m a dive. but when it hits 50bar (ie 100 in a single 12) i would expect them to be well on their way to the surface with only a 3min safety stop to do. getting to the surface a good 30-40 bar.


Edit: the one big point to mention is that if you are low on gas then the oct you go for is likely to be as low as you.

[yellowduke]

Good of you to cough up to the experience. Just remember there is always someone who has done something even more stupid. Yes that would be me but as the saying goes, we live and learn.

Jim

[Reikimaster]

Originally Posted by yellowduke

Yes that would be me but as the saying goes, we live and learn.

Jim

if you are one of the lucky ones. which is why when you do you should tell people so they can learn from your mistakes.

[divertim]

[quote=Harlequin].

So, I signalled (yeah, incorrectly) that I wanted air, but I forgot to preceed this with “Out of Air”. My buddy very kindly gave me his primary and as I saw him put mine in his mouth I took a long breath, pulled his reg out and shook my head “No air in that mate” and handed his reg back while I grappled for his octopus. Just one minor issue though, well 2 actually…

1. His octo’s hose was trapped under a reel so although I could get air I had me head stuck under his armpit. Fun eh…?
2. He was probably quite low by now as his main reg freeflowed while we were beathing off it.

Another diver came along about a minute into this fiasco and I simply saw a nice lurvely looking yellow octopus in front of me so grabbed it and stuffed it in me gob.


So that'll be me then.

Ok Harlequin, that's not a bad recollection of the events, almost accurate, and I think that we both learned a lesson. You never stop learning in this game do you?

Just to fill in a few points. We both had 100 bar left at the exact same time, but the dive guide was lost and we didn't know what he was trying to do. I shot off after him to get his attention. When I caught up to him I was down to 50 bar so I unclipped my reel. I realised then that we were back at the shot so I clipped it back on. Unfortunately I clipped it back on over the top of my AAS hose. It's probably the first time I've ever taken it off and put it back on again, so it's obviously Sod's Law that we were to have an Out Of Air Situation on the trapeze.

You correctly admit that didn't give a clear signal that you were out of air, and it takes a brave man to say that in a YD Forum. The signal you made gave me the impression at the time that you wanted to try out my Apex Black Pearl Reg, that's why I took yours. Only when I sucked on it did I realise that you were empty.
Luckily Liz was on the trapeze with more air than the rest of us put together.

Remember
Don't wait to see if you can find the shot, get reeling up on (at least) 50 bar
Give a CLEAR signal that you are out of air
Turn the reg facing down so it won't free flow
Carry more than one pressure gauge (I carry a transmitter with two computers and one SPG)

We learn by our mistakes (except sky diving), and it can only make us better divers.

Tim

[MattS]

Originally Posted by Harlequin

Why do we surface with 50 Bar...?

50 bar is a reserve. It has no specific use other than having a breathing and buoyancy source when otherwise you would have nothing. For instance, the main reason to keep your reg (and mask fitted) while boarding a boat is so that you are not left breathing water should you slip off the ladder/lift etc. It is also not unknown for the boat to have to manouver quickly (drifting onto rocks, rough weather etc). In which case hurling yourself off the ladder backwards might be the safest (only) thing to do. Engine fumes will not kill you, breathing water will.

Your 50 bar reserve could be worth less than you think. Regulators need a pressure behind them to work, which depending on the type/make/model can be between 10 and 25 bar over ambient.

Greatest respect for posting the report. I hope you do not mind if I add to your evaluation list

Never again will I ascend with so little in my tank as it really brought home to me how inaccurate gauges can be.

Irrespective of the accuracy of the guages. As you found out real life air shares do not always (rarely) go as smoothly as the training drills. It's nice to have something to breathe while you sort it out. For instance, had you had a couple bar in your cylinder your rescuer would not have been placed OOA when he took your main reg. You could have then shown him your guage to re-inforce why you asked for his air supply. Similary, it is possible to lose contact with your buddy during an assisted ascent (on your buddys octo). Having a few bar of your own left to fall back onto will keep you alive while you work out what to do next. Keep in mind that the shallower your buddy manages to get you the longer that few bar is going to last.

So yeah, always act sooner rather than later - never, ever, run out of gas.

If I do, and hopefully will not, but if I do run out of air then I’ll give the proper signal.

Signals need to be clear and unambiguous. Don't get embarrassed about them. The idea is to leave absolutely no doubt as to what is about to happen, whether changing direction, signaling OK or enquiring to your buddies remaining gas. Confusion is the very last thing you want during a sticky moment, keep the signals simple (to bend a phrase).

I could very easily have caused some serious damage to myself or my buddy.

Yep. Without wishing to criticise, your inaction increased the stress of the situation. My personal oppinion is that stress is THE most dangerous thing underwater. Avoid at all costs.

Additionally:
Have you thought about your priorities? Given the profiles and the lack of mandatory stops on reaching the trap, the chances of getting a bend were very small indeed. Better bent on the surface than trying to breathe water at 5m as they say.

Hopefully my points will help you learn as much as possible from what was probably a fairly traumatic event. Believe me I have had my share of learning experiences.

Again, good to hear you got out of it relatively unscathed.