Blog posts from Gareth, Imogen and Neil
Firstly, let’s clarify a few issues. The name. GUE calls it a “valve drill”. I have heard instructors from other agencies call them the same, but divers from all other agencies refer to it as a “shutdown”. There is a reason behind the alternative wording, but for simplicity's sake I am going to ignore the semantics and use the terms interchangeably.
Although the minutiae of the procedure may differ form agency to agency, it can be taken as pretty much universal that being able to reach and manipulate your valves when diving a set of twin cylinders is a “good thing”, and that not being able to reach them is a “bad thing”. Just how “bad” is an endless debate, so let’s not go there. Additionally, my experience has been with a set of twins that have their valves pointing towards the sky when I am standing up straight, so that is where the focus of this document will be. Not everyone does this, and the pros and cons of “inverting” cylinders is another endless debate.
Before we get hung up on kit and configuration, let’s talk a little about physiology. How exactly do you reach for the valves in the first place. There are two ways of reaching back.
The first way involves keeping the forearm parallel to your body and rotating your shoulder, so that so your entire forearm moves behind your head. I have seen people manage to reach their valves like this, but you have to be very flexible, and it looks far too much like hard work.
The second way will give you another two to three inches of movement. Bend your arm at the elbow, but keep your elbow facing forwards, with the inside of your forearm tucked in close against your head. It’s a conscious effort to keep it in that position, if you relax your arm will rotate, so keep that forearm close into your head. Now rotate your shoulder and push that arm back so that you can still see your elbow, but your lower arm and hand have disappeared past your head. This is a much better position to be in, and give you more flexibility. It is also a position that can be extended by training and exercise, which I will discuss later.
Reaching back for the isolator with the right hand is almost identical, except there is a little trick to it reach back, as in option 2, above, but this time bend your hand 90 degrees up at the wrist and then put the inside of you wrist against the back of your head. Now push back with your head. You hand should just land on the isolator. Reaching for the left hand post is the same as the right hand post, but wit the left hand. However, this is the valve that causes most people problems simply because they have less flexibility in their left shoulder than they do in the right. This can be helped with specific exercises, which I will document later.
Now we know how to reach back, we need to make sure everything is set up to allow you to stand a chance of getting there. Tip number one is to put your kit how you want it and leave it alone. It doesn’t really matter if that condiguration is DIR, DIFF, DILLIGAF or whatever, but once you have your kit setup correctly, leave it alone and start diving it, because you need a few dives with each configuration before you know what’s what. Changing things every dive will just leave you in an endless circle of adjustment.
The configuration below works for me. If you want to do it another way, knock yourself out. If you do not have your harness, backplate and twins set up correctly, then it really doesn’t matter if you are Mr Stretch, Captain spaghetti, or the incredible bendy woman, you are not going to get to those valves. Now “correctly”, in this article, refers to how I’ve finally ended up with my twinset configured. This is “correct” for me. The combination of the elements I describe allows me to reach the valves. Please don’t whinge at me if you don’t happen to like having your rig the same way, I’m trying to be helpful here!
Let’s start with the twinset. I really have lost count of the number of divers I see moving twinset bands up and down their cylinders whilst at dive sites, in attempts to reach their valves, totally forgetting about what this will do to their trim etc. I was that diver for a few months so I certainly cannot claim I haven’t been there myself. Move the bands to just below, and I really do mean just below, the neck of the cylinders. Then leave then alone. Really. It’s a seemingly common belief that moving the bands down a cylinder will move the valves closer to your hands. Let’s think about that. Your twinset is a straight line, but your back is a curve. Moving the bands of the cylinders down therefore moves them up in relation to your back, but actually moves them further away. The closest they will get to your back will be if you set up your cylinders as in Image 3. I spent ages mucking about until someone physically demonstrated that one to me.
Ignore the barrel o ring versus facing o-ring nonsense. Pay scant attention to the MDE versus the world guff. Laugh in the face of the balanced versus unbalanced valves argument. There are but two types of valves in the world. There are those that you can shut down, and there are those you can’t. When your supply of life giving gas is rapidly bubbling away, that is the only distinction that matters. So how do we make sure the valves are as helpful as possible. Well, the first thing we can do is replace those silly hard plastic knobs that come with many manifold and valve sets. They are a crime against humanity. Replace them with rubber knobs, which you will find longer (hence that bit easier to get to) easier to grip, and easier to keep grip of. Next is the valves themselves. MDE valves, whatever people say about them, are fairly simple to turn, so we’ll leave them alone. If you have the other type, be it DIR Zone, Scubapro, Halcyon, whatever, then strip them down every couple of months, clean them and regrease them with O2 grease. It makes an unbelievable difference to how easy the valves are to turn.
Backplate and Harness
Right, so that’s the cylinders sorted, what about the back plate and harness. Well, lets go through a fitting.
Take the back plate off the twinset and put the harness and plate on. Don’t do up the crotch strap of waist strap. Reach back with your fingertips. You should be able to touch the top edge of your plate with either hand. If you can’t do this, then your harness is loose. Now this will no doubt cause an endless debate, but if the harness is loose, then sooner or later the twinset is going to shift down your back slightly moving the valves further away from your hands. So stage one of fitting the harness is to tighten up those shoulder straps until you can reach the plate with both hands. For those of you not familiar with your set rigged like this, this is going to be weird, because it feels like the shoulder straps are very tight indeed. A tip for getting the shoulder straps the same length – stand on the crotch strap, if you have one, and just lift the shoulder straps, you should then be able to tell visually if they are the same length.
Once you are happy with the shoulder straps, it’s time to adjust the crotch strap. I’m not going into the waist strap because from a shutdown perspective who cares. The crotch strap, however, is important. Too tight, and it’s going to pull the backplate down away from your shoulders. Too loose, and it’s going to allow the backplate to ride up, creating the same scenario when the bands are moved down the cylinders where the valves actually move away from your back. If your waist strap comes horizontally across your body from the slots in the backplate, then the crotch strap wants to come between your legs and about 1 inch higher than the waist strap when pulled taut. That’s the general plan, now do the whole thing up and see if you can still reach back and touch the backplate.
That’s your SCUBA sorted, but what about the clothes you are wearing.
Thermal Protection: Drysuits
Few divers are forward thinking enough so that when they purchase their first drysuit, they think to themselves of their future diving needs, and see the potential for twin cylinders in that future. As a result, drysuits are often ideal, or at least acceptable, for single cylinder diving, but are totally inappropriate for twinset diving. Although many agencies teach that being able to reach back and open a valve with a single cylinder rig is a Good Thing™, this skill seems to be lost once any formal training is over. I have to be honest and say I’ve ever seen one diver practicing this in the water with a single rig. So, it really only becomes a conscious requirement, and indeed an obsession, once a twinset is purchased.
It is in the area of the chest, shoulders and arms that drysuits tend to let people down with regards to reaching their valves. Reach back with your hand as if you are reaching for a valve. Now we’ll go through a checklist for the suit:
Well, that’s a bunch of you looking at your beloved drysuit with disdain and horror. Sorry about that.
Thermal Protection: Undersuits
Under the suit we encounter more problems. Try getting into your drysuit naked. Go on, you know you want to. You’ll find you have a great deal more flexibility than you normally do. As you add layers and bulk to the inside of the suit, the less flexibility you will have. When purchasing a drysuit, you need to think about the maximum level of thermal protection you will have with that suit, so that you are not left in the position of several divers I have encountered - being able to do shutdowns in summer, and not in the winter.
Now put on your normal undersuit and drysuit, and just stand up and reach back over your head. Just stop and think about where you can feel any restriction. If you do have an issue with the undersuit, the resolution might not be as costly as with an inappropriate drysuit. There are several manufacturers of undersuits, such as 4th element, that make very warm underclothes that are far less bulky than both the Weezle type suits and indeed the Thinsulate type suits. It’s not my place to say what you should and shouldn’t use, but I recommend using what keeps you warm and allows you mobility.
This one seems obvious, but it caught me out. I love my 5mm gloves, but I do struggle to shutdown my valves in them because I lose a great deal of tactile sensation and indeed grip in them. 3mm gloves will offer you more in the way of grip, but may be a little cold at certain times of year. I find drygloves great – when they work. As with just about everything else, try some and stick with them a while before giving up. Perhaps try with thin gloves and graduate to thicker gloves once you can turn the valves – but just remember there is a flip side to that – once your helps freeze, shutdowns become rather more challenging.
I thought I’d avoid this one, but it will no doubt appear on any subsequent thread so let’s just get it out of the way. This is one of those TRUTH moments, where you have the priveledge of sharing something which many people seems to struggle with but is an undeniable fact. Are you ready? Here we go. Inverted cylinders are easier to shutdown. Sorry!
There’s so many pros and cons of both ways that I am not going to get into it, but the fact remains that from a perspective of shut downs, inverting is the way forwards, so to speak. Many people adopt inverted rigs for this very reason. It doesn’t appeal to me, but then I can do a shutdown. The DIR mob claim that everyone can do a shutdown if their rig is properly configured and they are trained properly in how to trim and weight themselves etc. Well, for the Non-DIR crowd, there really is some truth in this I’m afraid. For the DIR crowd, it is “some” truth, and not the whole of the truth. Some people simply do not have the mobility in their joints and require another solution. This section is in here just to recognise and remind you that the contents are what worked for me, and what I learnt on the way. You may have a pre-existing condition that means inverting is the only way to do it, and if so, go for it! Actually, if you just fancy having inverted cylinders, go for it.
It’s nearly time to hit the water, so let’s kit up. Firstly, when you are putting your drysuit on, pull up the body of your undersuit so that you have some spare material in the top half of your drysuit where you need it, rather than being trapped in the bottom half near your legs. Make sure any spare material is around your chest and shoulders. Do up the drysuit. Now “do a superman”, by putting your hands together and stetching them up towards the sky, stretching your legs as well. This will ensure that your undersuit and drysuit are best placed for flexibility in the shoulders and arms, and that you are making use of that spare material you pulled up in your undersuit. Now put on your Harness. Rotate your shoulders a little in the shoulder straps to give them room. If you have any spare material in your drysuit, make sure it is above your waist strap where it will be useful for the shutdown, and not trapped below the waist strap where it is useless. Get in the water.
Trim and In-Water Attitude
I watched a friend and fellow diver attempt two shutdowns this past weekend, and they were completely different. The first was a disaster, with him not being able to do anything more than just touch the valves, kicking up silt and finning around, swearing through his regulator. The second time, he reached back and went through the valve drill in perfect order, experiencing no problems. Bizarre huh. Not really if you were there. You see, on the first dive, he was stressed and his trim was such that he was at about a thirty degree angle with his feet pointing downwards.
Let’s deal with those two facts separately. He was stressed. I could hear it in the language he used. Hell, I’m not even sure what some of the words meant, and certainly couldn’t spell them, but he definitely sounded annoyed. Try tensing up your arm, you will lose mobility as the muscles tense up. Now chill out and let your arm rest, the mobility will return. The lesson is if you are tense and having problems doing a shutdown, leave it and come back to it when you are feeling more relaxed rather than continue to struggle and get more frustrated. I try to control my breathing before a valve drill for two reasons. Firstly, it means I am not going to change depth (much) during the drill. But perhaps more importantly, it means I am going to be relaxed. Now this works for me, just do whatever works for you, but chill out for the love of God, because swearing and kicking about is not going to achieve anything and only make you more annoyed.
The second item in this section is trim. Now some types go on and on and on about trim. Believe me, I’m one of them and just as guilty as any other. There are many reasons for this, which I’m not going to get into here, but ONE of them is that it makes the valve drills easier. Think about it. If you are horizontal in the water, the valves are going to be where they are supposed to be. The further off horizontal you are, the more likely the rig is to slip down your back a little, and maybe just take those valves out of reach. So how does one achieve perfect trim. Yeah right. That’s for another document, and I’ll write it once I know the answer myself. However, even if we cannot achieve perfectly flat trim, we can use this knowledge to help us do a shutdown, or at least train how to do them. Instead of finning about in Stoney, or in a pool, practicing your shutdowns. Just dump all your air and lie on the bottom. That way you are going to be flat and stay in one place. You will also be pleasantly surprised to find that once you get over the sensation of laying on the bottom, you will relax, because you are not having to think about buoyancy, or trim, or position, or anything, just the shutdown. Marvellous!
Yet another important element here. Us GUE types run our suits very tight, managing all buoyancy through our wing. This makes trim and buoyancy more precise as you haven’t got air migrating around your suit but comes at a price. Next time you are in the water, drop a few metres without inflating your suit. Pretty soon you wont be able to reach over your shoulder at all. The squeeze causes the suit to lose all flexibility. So you need to have enough air in the suit to allow the suit to move. On the flip side, if you have ever been daft enough to inflate your suit to the maximum you will find a similar scenario, in that the air bulking out the suit means you cannot bend your arms or legs properly. So there is a happy medium. For me, this means putting just enough gas in the suit so that when I stretch my legs back, and my arms forward “doing a superman”, I can feel the suit moving over my body as it adjusts. This is another of those “get it wrong and you’ve got no chance” elements.
Flexibility and Training
The movement to reach back and get a valve is not particularly natural, but there are some good excercises that will help. I’d advise speaking to your local gym, who will in most cases give you sound advice on how to exercise the relevant muscles without damaging them. There are a few I use. For example, when you reach back, you can give your arm a gentle boost by pressing gently on your upper arm with your opposite hand. The key word here is gently. There are some excellent stetching exercises to be found here. Other useful in water exercises are having a buddy gently guide your hand to the valves, and just reaching back and holding them at regular points in the dive, just to get the muscle memory in. Also, have some honest debriefs when you get out of the water, where your buddy can tell you what your trim was like, how far your fingers were, anything else he or she noticed etc. Feedback is essential, becuase you cannot see what is happening.
What I’ve tried to do here is to brain dump everything I have learned about valve drills since I started twinset diving. I’m still putting the gloss on them myself, but if in this post I have given someone a moment to think “ooh, I wonder if it’s that that’s stopping me” then it has been worth the effort. Once again, I would re-iterate that this is simply the path I have taken to successfully doing the drills. It’s not necessarily the path for you. What I am not trying to achieve here is anyway intended to replace professional training. Finally, no matter what I have told you, there is no shortcut to this. Like all potentially life-saving drills, a valve drill is something, in my humble opinion, that should be practiced at every possible opportunity, and it is only that practice at the end of the day, that will get you there.