Saturday, April 24, 2010

BSAC versus PADI

Is it just a friendly rivalry?

I went to a dive shop today which offers training the PADI way. The owner, a Professional Association of Diving Instructor, asked me who I was training with and snorted distainfully when I said BSAC. He suggested that it wasn't too late to change, joining one of his courses.

When I first mentioned the possibility of diving to a friend, a few months ago, they immediately recommended that I train with BSAC. The British Sub Aqua Club training, they assured me, is for proper divers, not just the fair weather sort who'll only go into warm tropical waters.

Not surprisingly, they'd been BSAC trained themselves. I received the same advice from a member of Scot SAC, the Scottish Sub Aqua Club (who are different from the British version, apparently).

On their website PADI describe themselves as "the world's leading scuba diving training organisation", with over 135,000 professionals world-wide.

BSAC are "the UK's leading dive club and the sport's national governing body".

PADI have hundreds of training centres around the world, where you can sign up for a course. According to their website my local centre would charge me £299 for basic training, plus £100 if I wanted to do open water dives (that is, in a lake or the sea). The course fee includes supply of the necessary equipment.

BSAC, on the other hand, have lots of clubs around the UK, some of whom offer training. Their charges are much less, under £200, but they may not be able to supply all the gear you need for open water diving. My group supply everything that I need for training in the swimming pool but that's it.

PADI instructors make money from training people whereas BSAC don't - they're all volunteers and their charges simply cover costs, such as club membership and access to pools and open water for diving.

I'm sure that as I encounter more divers I'll discover more about this evident rivalry between BSAC and PADI. At the moment it feels as if PADI position themselves as the up-to-date professionals and regard BSAC as the well-meaning but slightly backward amateurs. From the other side of the pool, BSAC think of the themselves as the guardians of true diving and see PADI as focusing on deep dives into your wallet.

There is, I think, a healthy mutual respect between members of both organisations and they often dive together. At the end of the day, when you're under water you want the confidence that your dive buddy is going to look after you, regardless of whether they're BSAC or PADI trained.

The shop owner that I met today was definately pro-PADI and scorned much of the advice I'd received from my BSAC colleagues. But interestly, when he was out of earshot, his shop assistant, himself a regular under the water, confided that he envied BSAC because they did what he called "real diving".

Friday, April 23, 2010

Lesson Two

I don't really like water.

It's one thing to be downing a glass, putting it inside me, but I'm not so keen when I'm inside it. Particularly when I'm three metres down and being asked to take out my regulator (the thing I breathe through) and throw it to one side.

There are bits of this training that I'm not looking forward to. Jumping in was one, mask clearing is another. Then there's removing and clearing the regulator underwater, swimming without a mask, air-sharing, jumping into cold water, diving in zero visibility and... Actually, there's quite a lot that I'm not looking forward to!

It was a pleasant surprise to discover that removing and clearing the regulator wasn't as difficult as I'd feared. We practised on the surface, where I managed to swallow a mouthful of tasty chlorinated pool water. But three metres down, on the floor of the diving pool, it felt remarkably easy.

I took out the regulator, threw it casually to one side, then swung my arm to find it again and back in my mouth. A firm blow to push out the water and there I was, breathing again. I quite enjoyed the practice and even made a point of pausing for a few seconds between tossing it aside and trying to get hold of it again. Hey - I'm a scuba diver!

Mask clearing wasn't so pleasant and I can't claim to have mastered it. Divers wear masks that grasp their faces like limpets and which keep the water out. But we have to learn how to clear a mask in the unlikely event that water gets in.

I put my face under water, let some of the stuff trickle into my mask, then put my head back and tried to clear it. My nose stung as I inhaled chlorine filled water. I splutter and coughed and gave up. A second attempt was equally unsuccessful.

In hindsight I think I know where I went wrong. Divers learn to breath through their mouth because that's where you put the regulator. The nose is covered by the mask and becomes useless for breathing. But during mask clearing you blow out through the nose to push water out and the natural next step is to breathe in - through the nose.

I think that's where I went wrong and I'll test it out next week. Apparently I'll also be learning how to remove and replace the mask, including clearing it, when underwater. That sounds like fun.

So next on the tick list of challenges to overcome is mask clearing and handling the pressure in my ears. But I'm sure my instructors have plenty more in store for me!

Thursday, April 22, 2010

Under Pressure

Have you ever lifted a bucket full of water?

Heavy, isn't it? Imagine what's required to lift a diving pool full of the stuff, or what it would feel like to lie underneath it.

Because that's exactly what happens when you dive. Gravity pushes the weight of the water downwards onto you. What's odd is that you're not aware of it. This is where it gets all scientific and beyond my limited comprehension - somehow the interplay of forces on your body prevents you from feeling the weight, or from being crushed by it.

At least, it seems that way. In fact the air inside your body does get squashed as you dive, and you don't need to go very deep before you feel the effects. If you've ever dived into a pool and swum down to about three metres (or ten feet) you'll probably have experienced pain in your ears. That's caused by the air inside you being squashed - or by the change in pressure, to be more technical.

Even when you're not beneath the water your body is under pressure from the air. The invisible stuff around you, that you breathe in and out, has a weight. It's not very much, but when you're standing on the beach you're underneath about 35 kilometre of air (that's around 21 miles). That's a lot of air and it weighs about 2kg per square centimetre. All that weight is pushing down on your body all of the time - but you don't notice because you're designed to live in it.

Because water is a lot heavier than air, you don't have to go very deep before it begins to affect you - remember that pain in your ears when you dived to three metres? In fact, the pressure on your body doubles when you reach about 10 metres. Which means all the air in your body is squashed into half the space it usually takes up when you're on the surface.

Those first 10 metres are where you get the most dramatic change, as pressure doubles (or increases by 100%) from sea-level. At 20 metres the pressure is triple the pressure at sea-level, but it's only 50% more than the pressure at 10 metres. And so on downwards. Eventually, of course, it becomes unsustainable our bodies to cope, but by then we'd also be dealing with lots of other problems.

These changes have all sorts of implications for divers which is why training and practise is so important. At about three metres you might have a pain in your ears because of the change in pressure, but at 10 metres it could get much more serious.

For me, dealing with the pressure changes in my ears is the next serious hurdle to overcome. My first was being able to jump into the water and now I need to find a way to equalise the air pressure in my head as I dive. During both of my lesson my ears have hurt at the bottom of the diving pool (3 metres) and this week I still had minor ear problems over 24 hours after coming out. They've cleared now.

You're probably used to handling changes in air pressure - it happens when you come down from a hill or if you're in a descending aeroplane. I usually find that yawning or swallowing hard helps my ears to 'pop' or equalise. But you can't yawn under water and even swallowing is tricky. So I need to find another way.

I'm sure I'll find a way of dealing with it, and I'll have to if I want to dive deeper. But for the moment I do feel under a little more pressure than usual!

Monday, April 19, 2010

Following the Frogman

I blame Jacques Cousteau.

My memories of television in the 70’s are a mixed bag. Eurovision, Morecombe and Wise, Doctor Who and Star Trek all spring immediately to mind, along with those curious programme intermissions about a piston engine and a strange exhibition featuring odd noises and lots of lights.

The latter, I later discovered, was filmed at the Philips hands-on science exhibition at Evoluon, in Eindhoven, the Netherlands. I’ve been there and literally got the tee-shirt (although it’s a bit small now; I was about 8 at the time).

Another memorable highlight of early 70’s viewing were the underwater adventures of Jacques Cousteau. I watched enthralled as our small screen TV took me, in glorious black and white, into a mysterious world beneath the waves.

I was a little too young to appreciate the Apollo missions to the moon. I have dim recollections of joining my father for the occasional early morning viewing of something to do with rockets and space travel. But these giant leaps for mankind did not leave me with any enduring memories.

No, it was Monsieur Cousteau who grabbed my attention back then. He was also exploring the unknown but with the advantage that it was much more exciting visually. I remember watching as wetsuited figures with a tank of air strapped to their backs poked around in reefs and on the seabed. They encountered exotic creatures, natural wonders and, another fascination of mine, historic wrecks.

Of course they made it look easy. There was no talk of dive tables, pressure changes, safety checks or dive planning. At least, if there was I don’t remember it. My recollection is that scuba diving was about going places and seeing things that most ordinary people would never go to or see.

My drive to follow in Cousteau’s footsteps was never strong enough for me to do much about it. At University I dabbled in pot-holing, which doesn’t involve much water but was another experience that I wanted to collect. I don’t recall ever actively choosing not to pursue scuba diving – it simply remained on my ‘to do one day’ list, along with golf and visiting Peru.

Last year one of my daughters acquired a game for the Wii which is effectively a scuba diving simulation although, along with Cousteau, it overlooks all the technical issues associated with the sport. Inspired, she booked herself onto a diving course with the local sub aqua club. I went to watch her first dive, in 1.25 metres of chlorinated water at the local pool, and that was enough to whet my appetite.

I was faced with the prospect of accompanying her to more dives as a spectator, in the pool and later in open water. The alternative was to literally take the plunge (poor pun intended) and join her. When the other four on the course dropped out after the first lesson I decided that I’d keep her company.

But I know who’s really to blame for getting me into scuba gear - the late Monsieur Jacques Cousteau.

Thursday, April 15, 2010

First Lesson

There's power in fear.

I stood at the edge of the diving pool. Blue death lurked patiently under a smooth surface. The neat tiled grid dropped away to a depth of about three metres; more than enough water to swallow me whole.

As far as I know I've never, in my life, jumped into a pool of water more than a few centimetres deep. My memory is scarred by my first swimming pool encounter, when I was perhaps six years old, and I've distrusted deep water ever since.

I've stood here before, at the side of the pool, in a vain attempt to persuade a reluctant body to disconnect with solid ground. From time to time I've challenged my apprehension, questioned the logic and tried to overcome the stubborn refusal to give it a go. I have a one hundred percent record of failure.

It's not as if I can't swim. Weekly junior school visits to a swimming pool taught me nothing - it wasn't until much later that I gained the confidence to trust water with my own weight, and that's another story. I've rarely chosen swimming as a recreational activity and even less frequently have I ventured out of my depth.

But this time was different. This time I was wearing a belt with several kilograms of lead weights. I also had a heavy tank of compressed air strapped to my back. And I had an instructor waiting for me in the pool. This time it would also be much harder to walk away.

The fear was still there. The quiet blue water remained a threat, even though I was equipped to breathe below the surface. My confidence had already been boosted by a couple of lengths under water in the shallow pool, but one challenge still had to be faced.

My distrust of water is, I've come to realise, all about my need to be in control. I've always dreaded those fleeting seconds between committing to a jump and rising back to the surface. I don't know what it feels like because I've never done it, but my head tells me that for precious seconds I'll be out of control in a potentially dangerous and disorientating environment.

This time I was as in control as I could ever be. My buoyancy jacket was fully inflated, I had a mask and I had a continuous supply of air. All that remained was to push through forty years of irrational anxiety and stride off the edge into empty air.

I hesitated, took a few breaths through my regulator, and stepped out.