But what I meant was, when practising skill sets, one of which will be an isolate and shutdown routine there is a set sequence to follow... I've read it before somewhere but can't quite find it and can't remember the sequence.
When we practice the shut down for extended range or tri mix
First shut down the primary valve,suck all air out of hose, then switch to secondary reg, whilst breathing open the primary valve, shut down the secondry valve, then switch onto you primary reg and open the secondry valve again.
How come the isolation knob isn't brought into that routine as I thought one of the first things that was done during a real emergency was to shut the isolation valve to make sure that at least one tank is saved, re-opening the isolation once the offending bit of kit had been shutdown?
I believe that if you can definitely tell which post the problem is on, it is faster to shut that down directly rather than isolating and shutting down.
It's a case of "if this happens....." which in reality it may not be - ie a hose blows and you suddenly are engulfed in a bubblefest, so which side do you shut down, do you isolate or do you change you choose the correct post?
Add the isolator in before the 1st post shutdown and after opening the secondary at a guess......
Having been fortunate enough to have done some NOAA training, thought I'd give my two-cents worth:
We were taught to shut down the isolator first then shut down the problem reg. The training was done extensively on dry land (kitted up and seated) until it became instinctive. Thee was a kind-of sergeant major style to it so that the trainees were given a bit of pressure to test them. The NOAA manual is available via retail now, anyone going to the Dive Show might want to do a WHSmith and read that bit without buying it.:bandit:
Somthing goes bang or fizzz and you are surrounded by bubbles:
1: Isolate manifold NOW
At least you have half the gas left and if you have a slob knob or are double jointed that took about 2 seconds
2: Identifie source of gas loss (or if serious swap to back up reg if required or bail out to stage and ascend)
This could be any thing: High Pressure hose on deco bottle, reg free flow, O ring failure etc etc.
Identifie and shut down offending item if possable before total gas loss.
3: If apropriate re open manifold to redistribute un used gas to breathing reg and start ascent
Long and short of it is if there is a catastrophic failure in any air containier first move is isolate manifold. If the reg in your gob stops working thats a good indication that thats the problem so swap to back up reg. If that dosent work go for stage or look for buddy dammed quick.
You cant practice for the panic you will feel but at least if you shut down the mainfold in a few seconds you will more than likley have the remainder of one tank to get you to the surface so practice that.
Oh yes whilst you are doing all of the above start finning for the surface at a controled rate. Unless you have a total gass loss then the prefered DIR method is finn like bug#er
Cheers for that Mark, as usual as funny as f*ck... but!
My question was relating to practising skill sets, not a real incident, although I feel that you are right in your statement if the sh*t should actually hit the fan one day..
You see I've read articles on routines and these have dictated that the isolation is the first move, I've watched DIR videos on Fifth dimension and they run through a primary first, then isolation, then back up... others I've spoken too say go straight to primary and then backup without practising isolation..
I thought that a standard routine was practised by all and that one could time oneself from start to finish, but it appears that different organisations use different techniques, Although like you, in a real emergency I think I'd be happiest saving at least one tank of air.
Example - your spg goes fizz bang and disappears off into the blue. In this case as you know the guage is run by the primary post, all you need do is shut that, switch to backup and go....
BUT, here's the ring twitcher....
BANG! You are surrounded by a cloud of bubbles and something behind you has gone.... But what? Primary inflator hose, secondary reg hose, tank o-ring or what? If you shut A.N. Other post down how do you know (apart from the abatement in noise and bubbles) tghat you got it right? What d'you do if you got it wrong? You could now have no air supply until you switch that post back on and then isolate the other - major loss of time and gas.
Basically, if it's immediately obvious then you can save time and brownies by going for the duff post. If not, go for the failsafe and shut the mannie to at least save half your gas....
Been thinking more and more seriously about the inverted set up, AFAIUI the only thing I need to do now is get longer reg hoses - what length hoses are you using Wreckie?
And are there any other current "invert" users on the forum?
Quote Example - your spg goes fizz bang and disappears off into the blue. In this case as you know the guage is run by the primary post, all you need do is shut that, switch to backup and go....
The SPG is fed from the left side or secondary post, as is the backup reg and drybag inflation (If not using an Argon bottle that is).. You've been at Emmas cooking sherry again haven't cha Drifty me ol'cock! Also you'll notice that I already agree that in a real situation I'd would go for the isolation first, but!
I was talking of practise routines.. you know, like turn off primary valve, breath down reg, move to backup reg, open primary valve, close isolation valve, open isolation valve, close secondary valve, breath down reg, move to primary reg, open secondary valve...... check time taken etc..
There appears to be some variation in routines according to who you ask, I was just initially trying to get a handle on.. as the thread title say.. "Isolate and Shutdown routines" so that I can practise them in the wet, but things have moved on since I first asked the question months ago and I think I'll go with the GUE method described above..
(Edited by Dave Williamson at 6:32 pm on Dec. 10, 2002)
The SPG is fed from the left side or secondary post, as is the backup reg and drybag inflation
Mine wasn't :wink: We're not all of DIR config Mr. Willo
You've been at Emmas cooking sherry again haven't cha Drifty me ol'cock!
Not yet.... soon
I was talking of practise routines..
Practice for the worst case scenario me ol' duckie, that way when the widdle-inducing failure occurs you know you can cope with anything.... And if it's not all that bad you can shrug it off and be happy in ascending rather than thinking how much it costs to de-soil and undersuit.....
I think I'll go with the GUE method described above..
Davey, never figured you as George's whore..... :lol:
Just got back from La Hayhurst's gaff and, even if I say so miself, my new kit looks the Nads!! Just need to get my matching JetStream Regs (two) and DIN 1st-stages this week and collect my Turtles avec SS-fin-straps and the job, as they are indeed wont to say, c'est une good-un!! LARGE IT!!
The Halcyon 55lb Double-bladder Wing/Back-plate/back-DSMB-bag and webbing has been cut to fit and fits a treat....though I think Andy making me wear all this and just a nappy was a bit much!
Isolations and shuts-down Davey?? Get in the water and let's play!
I always used independs but maybe next year switch to manifold twins. So I am not talking trough experience, I read somewhere that you can only open the isolation manifold 1 turn as air will still migrate slowly and will be faster to close, this way it will take a couple of seconds to close iso 1 turn and at least save half gas. In a real situation I would go for isoolator first as if you close wrong side you would have lost a lot of gas...what you think?
Hey Wreckie,we're in a minoroty here y'know!I've gota twinvert set but it's stillin it's RN config so it's just got the 1 DIN on the manifold...rule of thirds again.I too can't really be arsed,just shut it down/turn it on and if you need repeat till in the dry bit.
Steve,Andy 2 tanx has been experimenting with his twinverts so he'll be handy to talk to.My old Man uses ex-police(twinverts) sets but on standard length hoses!!
Mail me if you want more on that.Right,hoses.If you go the independant route you'll probably need longer hoses for the DV's,try it first though as you may find they reach...sometimes.If not you've got a couple of options.Sherwood do long hoses as standard,as I beleive do a couple of others.See if these are suitable for using with your 1st/2nd stages,remember you can always use adapters if needed.Standard type hoses can be made up by SCUBA suppliers but they're usually priced accordingly.A betteroption is to find an industrial hose/hydraulic specialist in Yellow Pages etc and get them to make you up a set of Aeroquips or similar,just tell them the lenght you need and the working pressure.Get stainless fittings etc. too as some are alli.They usually cost about £20 tops.