Bending the rules
Divernet
Doctrine and dogma dont sit happily with thinking divers. Strict rules are all very well when were learning to dive or mastering new techniques, says John Bantin, but we also need to know when to throw away the book

THE ESSENTIAL DIFFERENCE BETWEEN TRAINING TO BE A DIVER and training to be an astronaut is that the latter, once qualified, rarely spends much time in space.
     For astronauts, clearly defined working procedures are an essential way of preserving lives in a hostile environment.
     On the other hand divers, once trained and diving regularly, or in concentrated bursts, should become so well practised that they dont have to think about routine matters. They can develop beyond the rulebook and start thinking for themselves.
     When we first learn to dive, there is a lot of information to take on board, so dive training organisations have put together vital systems of rules and routines to keep us out of trouble.
     Each agency has its own way of doing things. This invites tribalism, though those divers who indulge in badge-bashing do so only because they have little imagination. They can follow only one set of simple rules.
     But people differ. While there are those whose mentality dictates that anything but slavish following of a predetermined plan would spell disaster, there are others who never waste time practising for anything. Their activities are joyfully chaotic and may sometimes be thought dangerous.
     The preset routines we acquire when we learn to dive can give us confidence, but that confidence is misplaced if we expect any unforeseen circumstance to follow a predetermined plan.
     If you are an instructor delivering the prescribed product of a training agency, you have to follow its standards and procedures. Its like any franchise operation. No-one wants to go to MacDonalds to find some maverick chef doing his own interpretation of a Big Mac rather than the approved version.
     If you are cooking at home, however, you can improvise and experiment to your hearts content, as long as theres no danger of you burning down the house or poisoning yourself or others
     If, while diving a shallow coral reef in the Red Sea, it pleases you to follow a set of carefully thought-out rules developed for a particular group of cave-divers during one project in Florida, so be it. Simply be aware that there may be other equally appropriate ways to approach the exercise, and they may not be covered in the rule-book.
     If you think rules are sacrosanct, stand by for some heresy:

going into the red
Do you never take your pressure gauge reading into the red section Do you always get back in the boat with at least 50 bar left in your cylinder
     Why You get no credit at the compressor station for unused air, and the last 50 bar is as good as the first 150.
     Clearly, any instructor wants to know that his trainees are leaving themselves a good reserve, and in a rough sea you should have gas put by in case you need to breathe off your regulator at the surface while waiting for a pick-up.
     In calm conditions, however, is it not better to use this spare air to allow you extra time in the shallows to off-gas slowly Of course, air-management skills are vital, but I have seen divers at 6m under their boat on a mirror-calm sea getting anxious because their pressure gauges have reached the red line.
     They need to realise that even a tank as small as 10 litres and containing only 50 bar of air will last the most unfit or frightened diver around 13 minutes at 6m.
     No-one should care how much or how little gas you used during a dive, nor how much is left in your tank once you are safely back on board, provided you had enough to complete the dive safely.

the snorkel habit
Do you insist on having a snorkel permanently attached to your mask Why Because that is how you were taught
     An attached snorkel tends to shift the mask as it moves and makes it prone to leak water round its skirt. Why is the snorkel so important to you For use at the surface after the 50 bar reserve has run out
     I prefer to inflate my BC (orally if necessary) and swim backwards so that any waves break over my head. This approach causes me few problems, but thats my choice.

mask-off position
I have occasionally been shouted at for pushing my mask up onto my forehead. Some say it is the sign of a diver in distress, or that you can easily forget it and lose it up there.
     Its funny that the likes of Hass and Cousteau were photographed so often with their masks on their foreheads. I wonder who shouted at them
     If you wear a hood, its true that you may forget your mask is on top of your head and lose it when you take the hood off. If you are not wearing a hood, however, you would have to be pretty unaware to forget that it was there.

how does your octopus hang
Do you have your alternative air source or octopus rigged on the same side as your main regulator Why Is it for you to use
     If you rig it from a medium-pressure port on the left side of your regulator first stage it will be very awkward for you to use but ideal for a second diver who might be out of air. Is that not what its for
     It is very unlikely that you will ever need it for yourself. Your primary second stage will fail only if there is a problem with your first stage, and it should go into free-flow if that happens.
     You will not need your octopus unless you went in with a regulator mouthpiece that was holed, giving you a wet breathe, and had not checked it first. So rig your alternative air source for someone who might need it.

blowing off
What about that peculiar business of blowing air from your cylinder into the first stage of your regulator after the dive - a ritual that leaves the aft deck of a dive boat sounding like Kings Cross when the Flying Scotsman arrived.
     The inside of the first stage is already dry, because it was on the pillar valve of your tank all the time it was under water. To blow air at it is probably to blow peripheral water inside it, causing maintenance problems to come.
     The rubber blanking cap does need to be cleaned and dried, but you can do this quietly with a towel.

hanging about
Often club divers are reluctant to abandon techniques they use at home, even though the local operator has a good reason for wanting things done differently.
     In the English Channel, for example, it is best to jump from the boat with some air in your drysuit or BC, so that you bob to the surface and can confirm to the cox that you are OK, before descending.
     Do this in fast-flowing ocean currents somewhere like the Maldives, and you will end up drift-diving alone.
     There are times when you need to hit the water and get down fast. You have to rendezvous with your buddy close to the reef, even if this is not your training agency-approved method.
     Similarly, new divers who have been taught to roll over from the inflatable but keep hold of a grab rope should be aware that most coxes would prefer them to get clear of the boats propeller as soon as possible.

the big O
We all know that the agreed CMAS signal to indicate that a diver on the surface is all right is the standard OK hand-signal with raised arm. However, in most parts of the world, where the local man has never heard of CMAS, the boat driver expects you to make a big O shape with two hands over your head.
     Photographers with cumbersome cameras may have to improvise with one arm, but there is no point arguing about it - when in Rome, speak Italian.

computer code
Some strange rules have evolved regarding computers. For instance, if yours shows a 3m stop, this does not mean that you should go as quickly as possible to 3m and wait for it to clear!
     Good computers calculate as you off-gas on the way up. Its called continuous decompression. A slow, thoughtful ascent is generally believed to be an important aid to trauma-free off-gassing. Some divers even recommend deep stops.

mixing your gases
I sometimes do a leisure dive with two independent cylinders on my back. One is filled with a nitrox mix that I can use to the maximum operating depth planned for the dive, while the other is filled with a richer mix for accelerated off-gassing in shallower water.
     This technique has been highly criticised by some. They say that because I go beyond the maximum operating depth of the gas mix in one of my tanks, this is dangerous. Why Because, they say, if I put the wrong regulator in my mouth I could sustain an oxygen hit.
     That may be true, but why would I put the wrong regulator in my mouth First, each is clearly marked as different and, second, I would have started the dive using the regulator for the deep part and only look to swap to another regulator during the ascent.
     Why is it any more dangerous than having my deco-mix in a tank slung from my BC Why would I not be in danger of putting that regulator in my mouth beyond the maximum operating depth for the mix

why twins
You are probably aware of all the controversy regarding independent twin tanks, manifolded twins and manifolded twins with an isolator valve between.
     Each has its merits, but if maximum volume of gas is not the issue, what about a single large tank with an H-valve and two separate regulators It works exactly like a manifolded twin with an isolator but it is much quicker to shut down an offending side if needed, because there is one fewer knob.
     I know a lot of British divers will hate that idea because it is not what they were taught to use, even though it is almost standard practice throughout Europe.
     A-clamp v DIN
     What about the business of international A-clamps versus the DIN connection for attaching your regulator first stage to your cylinder
     The latter is certainly better in many ways, not least because it is more difficult to dislodge if knocked, perhaps in a confined space, but the A-clamp is almost universally used within the American sphere of influence. Thats most of the world now.
     So if you are not matching your own regulator and tank, you might have to use a connection that is not your first choice.

hero or villain
What about touching the reef What about that most vilified, yet least understood by those-that-vilify, item of diving equipment, the reef-hook
     The reef-hook is used to prevent damage to a reef, not to cause it. In a current, it is used to anchor the slightly buoyant diver clear of the reef and thereby avoid doing any damage to it. Naturally, you have to be circumspect about where you hook it, but it does a lot less damage than gloves, or ill-placed knees and fins.
     A gentleman who wrote a letter to both this and another magazine protesting about the use of reef-hooks confessed to me that he had neither had any experience of these tools, nor had he actually seen one. That didnt stop his letter-writing!
     The term reef-hook is too emotive - perhaps we should start referring to them as current claws.

diving the plan
Take a group briefing by a dive marshal before a days charter-boat diving. Once a plan is decided, disappointment is understandable if the skipper suddenly changes everything moments before the group is about to enter the water. But the sea is changing all the time, and a good dive marshal must have plenty of options up his sleeve.
     Doggedly following a predetermined plan in the face of changed circumstances is a recipe for disaster, yet it happens all the time.

personal hygiene
Heres a rule I would not mind seeing observed. Never pee in your wetsuit. If you can last the night without wetting the bed, I am sure you can last for an hour-long dive, however cold it might be.
     The smell from fouled wetsuits is both appalling and also very unfair on boat crews, who may need to take their meals close to where the offending garments are hanging to drain.

all by yourself
This used to the best-kept secret of the diving world. Diving instructors do it when diving alongside novices. Dive guides do it when tying off boats to submerged mooring points. Underwater photographers and those with whom they are nominally paired do it to satisfy the notion that every diver should have a buddy.
     People have been solo-diving since diving was invented, but only recently has anyone openly admitted it.
     Buddy diving pre-supposes that both parties of a buddy pair are competent to rescue the other should the need arise. Some are quick to say that if you dive alone, you will die alone.
     Alas, the corollary of that is that those who dive in pairs are likely to die in pairs. So solo-diving could actively reduce the number of casualties - if each diver was competent to rescue him or herself.

     Training gives a good basis for handling what confronts you in real life. It cannot be underestimated. However, good divers try to accommodate whatever the prevailing circumstances present. A good diver does not dogmatically follow procedure just by habit and he does not break rules because of an inability to follow them. He makes the best use of information to hand and thinks for himself.
     If you can think of other examples to add to the 15 here - or if you just want an argument - write to Off-Gassing now!

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