​The internet has changed many aspects of diving, some for the worse and some for the better. It has never been so easy to find out about different dive sites or to hook up with like minded divers. Dive forums allow the novice divers to connect directly to ‘experts’ just waiting to answer their apologetically-asked questions. In fact most forums rate the users by the number of posts as if to provide some sort of credential for the usually anonymous forum member. In dive forums as elsewhere on the internet there is a need for caveat emptor.

I run a dive centre and probably do more than the average number of dives in any given week, though sadly if I lived somewhere warmer and calmer I know I would do a lot more. I struggle to keep up with daily emails, text messages to and from divers, calls to suppliers and that’s without the customers coming into the dive centre as well. As a consequence I rarely dip into the forums and only usually for topic specific threads. When I do read through forum threads I resist commenting unless I have direct knowledge of the matter. I wish that others would exercise the same restraint.

For the average club diver simple economics dictates that they must be in some sort of paid employment to finance the diving activity. I’m lucky in that I can play with my kit as part of my current job, but I think that would have been frowned upon when I was involved in scientific research in a hospital, and I guess not many employers are much more understanding either. So a paid job and the travel to get there and back must take up a fair chunk of the 168 hours available in a week.  A 9 to 5 job plus a bit of commuting accounts for around 47 hours a week.

For all of us there are the basic human needs for food (including shopping and cooking time), sleep, travel, family commitments and at least a little social life that doesn’t revolve around diving. Where on earth does anyone find time to make 50 posts on a dive forum a day and still find time for doing enough diving to become an expert on all matters? I am working on a mathematical description of this phenomenon. It is obvious to me that N [number of posts] must be inversely proportional to L [number of logged dives] but I think I may need to include extra terms to account for A [number of different diving agency qualifications held], C [number of years on Branch Committee], F [number of years as member of forum] and I [number of years as an instructor]. I will be collecting data to further develop my theorem over the coming months.

If we assume that my basic concept is correct then we must be cautious of high frequency posts from forum members. The time spent making those hundreds of posts is time that isn’t actually spent diving. Internet ‘experts’ are probably as reliable as those offers of millions of dollars from a Nigerian government official who died in mysterious circumstances. Have you ever wondered just how the experts know so much about so many aspects of diving? I know I do but then I have the experience to sieve through the information that appears on the forums. Do new divers possess the same scepticism or will they make important, life-critical decisions based on what they read on the internet?

​A few days ago a young lad came into see me. He had bought a cheap drysuit from a store that was closing down. His plan was simple. He had trained as a scuba diver on holiday last summer and was also friends with lots of the fishing boat crews. So armed with his entry level qualification he was going to help out his mates, changing anodes, untangling propellers etc. He’d been on a forum and worked out that he needed 8kg of lead for his 4mm neoprene drysuit. He had not ever been trained in how to use a drysuit and declined my offer of a course because he’d read the notes for a drysuit course and read lots of forum posts about whether to put air in the suit or his BCD. His drysuit came with neoprene socks, so he wanted wetsuit boots to go over the top of the socks so that he could walk down the harbour steps. He read that on the internet and he declined a pair of rock boots. A few days later his father rang to say that all the seals on the suit required replacing and his son had read on the internet that silicon seals were the best thing and ask if we could fit ring systems etc. It’s all just wrong on so many levels…but can we offer him any advice? There’s no need as he’s got it all off the internet!

​One of the joys of running a BSAC training centre is that I get to teach diving all year round rather than the usual branch approach of teaching across winter.  Many branches are lucky enough to have a good core of instructors and if you are asked to teach one of the theory lessons for the Ocean Divers that might be your entire theory allocation until next year.  By contrast I find myself able to deliver the Ocean Diver and Sports Diver lessons without reference to the visual aids.  I have to keep checking that I have actually said the crucial piece of information during this lesson rather than the one I delivered a few days ago. 

With practical skills, I find it much easier to ensure that I’m not suffering from déjà vu.  Individual divers are so variable and the practical skills are so obviously progressively taught that every lesson takes on a unique character.  PADI instructor exams include an element of fault correction during the teaching section as fellow candidates are briefed by the examiner to do daft things like trying to put on a mask upside down.  BSAC instructor exams don’t need this element as any instructor regularly helping out with training will experience a wider range of trainee diver ‘cock ups’ than any examiner could conceive of!  And it is those trainee mistakes, variations in technique, different attitudes and different characters that really make every practical session a different beast.

Rescue skills are a particular bug bear of mine.  My initial training included some really poor technique that meant any rescue I attempted was likely to be at best ineffective and at worst dangerous.  My potential for drowning an already unconscious casualty was never going to improve a bad situation. Luckily at some point a National Instructor was invited into our branch and we tested his diplomacy skills to the maximum as he patiently corrected the endemic poor technique.  I learnt a particularly good technique and I hope that by now I have done it enough to overcome the possibility of returning to my original training under stress. 

Even though I hope none of my students ever need Rescue skills, it is an aspect that I particularly focus on.  I’m sure everyone knows that skills go out of practise and it’s a brilliant idea to see clubs having an early season refresher that everyone joins in.  I have a theory that being rescued by an active instructor who has demonstrated and practised the drill several times in a year would be the ideal situation….unfortunately for me I am often diving with those who I have taught recently!  So ensuring they get the skill right is important for me as their buddy, as much as it is for me as an instructor.

But who checks my skills?  Do I claim to be the best instructor ever?  Certainly not!  But I do claim to be a reflective instructor.  I continually appraise how my lessons went, whether we achieved the learning objectives and, if not, why not.  And I talk to the rest of the instructor team about all of the lessons we teach.  We are all open to new ideas, we are all open to appraising each other’s lessons and to learning new ways of teaching the sport we love.  This isn’t a concept that is unique to diving, it’s a basic premise for achieving quality teaching.  Schools do it, universities do it and we do too.

Reflective practise doesn’t come easily to some.  It requires an open minded attitude and the humility to admit that you can make mistakes and, importantly, that you can learn from those mistakes and not keep repeating them.  BSAC’s incident report is a brilliant source of information to help you avoid some common mistakes.  Although some of the detail is limited in the published reports, it’s often easy to see where the ‘incident pit’ started and where you could hope to have intervened if you were in that unfortunate situation.  From my perspective, the earliest intervention possible is to ensure that really good skills are taught from the very first lesson.  I probably won’t be there when any of my students experience an incident in future, but the skills that I have taught them will be there with them.  I hope I’ve done a good enough job that everything turns out well.  I owe it to myself, my students and their future buddies to be the best instructor I can, and if anyone else wants to improve my techniques then I’m happy to learn.
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Just for the record, when my ‘student’ in my PADI instructor exam tried to put his mask on upside down, I had turned it over in his hand before he had even got it near his face.  The examiner told me off as I didn’t let the student make the mistake he had briefed for.  In my ethos, preventing the mistake was entirely the point.  I don’t want a student to panic trying to fit a mask upside down.  I want a confident and happy student who checks the orientation of the mask before trying to refit it.  My job done.

The world is littered with abbreviations, mnemonics and acronyms.  We use them to save time and energy repeating ourselves, shorten text messages for our lazy thumbs, remember key points and to establish a clear barrier between those ‘in the know’ and the rest of the world.  All this talk of what the DO said to the TO about the skills in SO1, and whether the CBL RBs and subsequent CCs were at the correct rate can leave a new member in the branch feeling like they have landed on another planet.  I once joined my very first team meeting in a college where I was doing some teaching that consisted of impenetrable discussions following these lines.  After 3 minutes I was bewildered and after 20 minutes I was starting to giggle and play abbreviation bingo in my planner.  But in reality such an experience can be off-putting at best and downright discouraging at worst.

So here’s a challenge: Have a look at your club notice board, website or newsletter.  Is it littered with acronyms that us British Sub Aqua Club members, the cognoscenti use with impunity?  Put yourself in the eyes of a new prospective member.  Would they be able to comprehend 75%, 80%, 95% of the information that you are presenting if they didn’t know what special code words you were using?  Some websites and newsletters avoid this pitfall, but others, put together by well-meaning and time-poor volunteers fall headlong into creating a barrier to others, right at the point where we should be welcoming and helping them into our world.

Sadly this problem is not limited to written materials.  Listen to an OWI or AI (or maybe still a CI) running a OW session and there will be a litany of BCDs, SEEDS, REAPs and ASs perhaps with some ppO2 and an MOD thrown in for good measure.  And as if this wasn’t enough to send you into a tailspin the instructors themselves will get hung up on memories of times past and terminologies encountered, so that terms such as DV, reg and 2nd Stage are bandied around interchangeably.  And confess now, who still refers to AAS in the occasional lapse?  And CPR instead of BLS?  We’ve all done it, haven’t we?

Of course, I am not arguing that we should abandon all abbreviations.  Anyone who has tried to draw up a dive planning sheet on the computer will be aware that there’s only so much space on an A4 page and you can only make the font so small or no one else will be able to read it.  The actual size of the font will of course need increasing as the age of the divers in your branch increases.  This usually corresponds the apparent shortening of one’s arms so that your dive computer display can’t quite be forced into focus, and leads shortly thereafter to the purchase of a dive computer with a larger screen or colour LED higher contrast screen.  This strategy is of course just buying time and bifocal lenses are looming on the horizon.  So in order to stave off the hideous reality, we can happily abbreviate to fit the information into the print out so that our dive plan doesn’t cover an intimidating number of printed pages.

In some cases though abbreviations can be an even bigger lifesaver.  Take the role of DM.  We all know it stands for Dive Marshall or is it Dive Manager?  Nevermind, I can safely hide behing the DM term without struggling to remember.  The Diving Officer’s Conference abbreviated to DOC saved us from misplaced apostrophes, and two years ago we changed the name to the Dive Conference.  But without fail the feedback every year includes reference to the DOC.  You can take an instructor to the bar but you can’t make him drink….oh well obviously you can’t stop some of them..but you know what I mean!

So  I’m setting a challenge to my own teaching and my instructor team to avoid the over excessive use of acronyms, especially with prospective new members and new trainees.  Perhaps I will introduce a glossary of terms list on the classroom wall?  Maybe I will award a wooden spoon style prize for the biggest transgressor?  Maybe I’ll start a diving abbreviations lookup website, like the ones that I use to help me decipher text messages occasionally?  As I was discussing the other day with the NDO and several NIs from the DTG and ITG at the NDC meeting at BSAC HQ, the first step to solving the problem is to recognise it exists…

Divers are a privileged section of society.  We have been places and seen things that even the most avid watcher of TV nature documentaries will not have noticed.  I’m guessing that not many film crews have hung out in Wraysbury trying to film pike, but anyone who has dived there has usually spotted at least one, especially if you go for the ‘circumnavigation around the lake’ dive.  The cost of underwater filming and the limited number of minutes or seconds of screen time mean that what the non-diving public see of diving is massively limited. In some respects it’s the equivalent of trying to infer the whole picture in a 1000 piece jigsaw puzzle by looking at just one piece of it.  Try watching the documentaries made about the filming of wildlife programmes and you’ll end up feeling massively sympathetic to the cameraman who spent 3 months sat up a tree to get 30 seconds of edited footage. 

A few years ago we worked with the Fish Fight team led by TV chef Hugh Fearnley-Whittingstall.  Hugh has been incredibly successful in campaigning against discards, the massively wasteful practice of throwing back the fish that are over quota as, even though the fish are dead, they can’t be legally landed.  This campaign has been fought at EU level where the fisheries policies are set.  I suspect a large number of people were surprised to find out that this even happens, as like most fishing practices it is ‘out of sight’ and therefore ‘out of mind’ too.  That series of Fish Fight programmes moved the argument on a little and looks at sustainable fisheries management, which was why the team headed for the Isle of Man, although we are a small island in the middle of the Irish Sea, we punch above our weight when it comes to looking after our marine resources.

To understand how this situation has developed you will need a little oceanography, a little history and a little politics.  The Isle of Man is a Crown Dependency (a bit like the Falklands but without the threat of invasion) and we have our own laws and govern ourselves.  For political reasons we are not directly part of the EU, but are represented at that level by Westminster.  So within the EU rules we can do what we like with our territory which for the most part is 12 miles offshore.  Over a hundred years ago Liverpool University set up a field station in Port Erin to study all things marine.  The site was carefully chosen as the confluence of warm southern waters and cold northern waters means that the Isle of Man is probably one of the most biodiverse sections of the British Isles.  Port Erin Marine Lab operated until 2006 when research was relocated to Liverpool to save money. However, many of the scientists remained on the Island and took up government funded roles, set up consultancies or became involved in charities with a marine focus. The legacy of the Marine Lab continues in our fisheries management.

The closed area outside Port Erin Bay was the first area in which scallop dredging and trawling was banned and within 4-5 years it was already possible to show that catches outside the area were on the increase. Nearly 30 years of closure means that the seabed looks as it should look, three dimensional, with tall seaweeds, seafans and hydroids galore.  The data from Port Erin is cited all around the world and has been globally used in the arguments for closing sea areas to damaging activities.  But that’s not all, we have restricted fishing seasons, restricted engine sizes, minimum landing sizes based on the reproductive ages of the scallops, a further four closed areas and active fisheries protection officers.  Hugh Fearnley-Whittingstall wanted to see all of this in action and ask why a small island of 80,000 people could still have a sustainable scallop industry when areas in England and Scotland had been fished to extinction. 
 

We've all experienced ear worms at some point in our lives. You know, the annoying little tunes that get into your head. Maybe you heard a snippet on the radio, maybe a song popped into your head or maybe you've been deliberately sabotaged by the boat crew in some cruel collaboration between the skipper and the deck hand? The source of that annoying little ditty is important.  Chance tunes played on the radio as you are listening out for the inshore forecast on the way to a dive are just unfortunate. But the songs picked by the boat crew are a deliberate attempt to get inside your mind!
 
During a series of marine survey dives on one boat we found out that the skipper's taste in music affected our surface time between surveys by up to 30 minutes.  As the strains of the "Irish Rover" blared out across the deck, we speedily changed to fresh cylinders, repacked our survey kit, drank, snacked and watched our computers to count down our nitrogen levels. Once those dive plan numbers had hit the magic 45 minutes we needed for the next survey, we were in the water to escape the music. Only we couldn't. I spent 45 minutes humming the 'Irish Rover' round and round in a loop in my head! It was a dire situation, made worse by not really remembering the words, as it’s a song I usually only join in with after a few drinks. So the tune rattled round in my head as I struggled to focus on the job in hand.  We got back onto the lift, handing across samples, quadrats and tapes to a grinning deck hand.  Once on deck we promptly questioned the parentage of the skipper, and from the grin on his face he knew exactly what he'd done. 45 minutes of my lyric poor version of The Dubliners hit was the cruelest joke.
 
Just before the next dive ELO's Mr Blue Sky wormed its way into my head.  If you listen carefully to the video recording of the sea bed you can hear me humming along. Hey there Mr Blue! Somehow that was less irritating, maybe because I knew more of the song and didn't get stuck in the same musical phrase for the entire dive.  But I've realised I'm very susceptible to ear worms and now like to avoid anything too memorable before I go for a dive.  I don’t play the radio on the way to the boat just to make sure.
 
A number of years ago a candidate on an Advanced Instructor exam pointed out that, as water enters your mask when you smile underwater, this facial; expression could be used as a way of clearing water too.  "All you have to do is smile" he said "And breathe out at the same time." Marvellous! Great logic. The trick is to stop smiling before you've fully exhaled, but that's just technique.  It was the ear worm that came with the suggestion that I have struggled with ever since.  I alternate between Lily Allen's Smile and Charlie Chaplin's Smile like some Glee club mashup.  I have been haunted by the advice to this day.
 
If the boat crew don't blast something at you, and your fellow divers don't offer advice that plants some repeating tunes, then watch out for any non-divers.  On a liveaboard trip where a few of us sat out the night dive, the strains of the Little Mermaid theme tune were swiftly called up from an iPod, just to ensure that everyone was humming "Under The Sea" before they stepped off. Those of us on the sun deck, beer in hand, waiting for the divers to hurry up so we could have dinner felt it was fully deserved.  The divers returned from their dive in record time. Job done!
 
In this era of easily downloadable music and quick to construct play lists, I have considered that I could do a selection of the worst songs to play on a dive boat.  The theme tune from Jaws would have to be on it, not because there is the slightest chance of seeing a Great White Shark with a grudge around the Isle of Man, but anyone meeting a basking shark underwater would discover that part of their brain which screams ‘Shark!’ and would hear the Da Dum playing in the background.  Now that’s an ear worm worth planting.
 

​It’s human nature to be hoarders. Thousands of years of human evolution has taken place without a row of shops in the high street or an out of town retail park to cater to our every need at most hours of the day. So humans have developed into hoarders, even if our modern day caves are overflowing with stuff. Witness the growth in ‘Self Storage’ facilities, a service that I am certain didn’t exist twenty years ago. How much ‘stuff’ do people have, that their homes are no longer enough and they need a portakabin sized extension, with lift access and on site security to keep their belongings? And for every organised, sensible person that realises that ‘extra storage space’ would come in handy, are there another dozen whose garage and sheds are rammed to the gunwales? Er…wait…yep that’d be me!
Across the winter months is a fine time for dive kit fettling. Just because the weather is less amenable to actual diving, doesn’t mean you have to spend your weekends doing something more useful. Non-diving partners will fail to see the logic in this argument. From their perspective you aren’t actually driving 2 hours to the dive boat to spend the day diving, therefore you must have time for a variety of other tasks, DIY, family visits, cinema trips, more DIY etc. The list of aspirations held by non-diving partners for days when you aren’t actually diving can be a long one. The length of their list is directly proportional to their lack of understanding about your love of all things scuba. The longer the list, the less they ‘get it’. Having established your weekly dive routine of disappearing from the household radar first thing on a Sunday morning and returning 12 hours later with an offering of fresh lobster, you must be very careful not to relinquish this time during the winter months.
So, what’s a diver to do when the weather is roaring in and the dive’s been blown out? It must be time to sort the dive kit. And this is a task that will take several blown out weekends. The longer you have been diving for, the more equipment you will have hoarded. If you are lucky enough to be the Equipment Officer in your branch then congratulations! You have an almost endless to-do list on behalf of your club. The act of ‘kit fettling’ on such a huge scale will ensure that your ‘dive time’ is protected as you justify needing to go to the clubhouse/pool/mate’s large shed where the club kit is stored by calling out “We need to have it ready for next season” as you head out the door.
I too have been sorting through kit. Dive centre equipment stores act like the extreme version of domestic garages and sheds. Who’d have thought we’d have not one but three Fenzi’s? Who knew that the kit box on the top shelf contained five two-piece wetsuits? And I think I need a bigger box for straps, clips and strange little bits of plastic that I can’t quite place, because I’m sure they’ll come in handy one day and I don’t want to throw them out yet. And there’s the rub, “it will come in handy one day.” I think I could make an absolute fortune if only I could learn to predict when that ‘one day’ moment will occur.
Our kit store should have a bench for kit preparation and rows of neatly stacked boxes.  In reality the amount of equipment in there means that the frequently used items are in on the floor in front of the storage boxes and the bench hasn’t seen daylight on its surface for months. Entering the kit store is like an archaeological project, everything is in layers relating to the time since its last use. The very act of tidying up is like a reverse trip down memory lane. But to combat the hoarding tendency requires more than tidying up. This requires a CLEAR OUT (cue dramatic music)!
There are three things required for a successful Clear Out. Firstly, you need to be in the right mood for it, ruthless, heartless, unsympathetic and a little cavalier. Who cares when ‘one day’ is likely to pop up? You need the space, you haven’t used this in 10 years and if you ever wanted to dive a horse collar again your mate has one you could borrow anyway. Secondly, you will make enormous progress in your decluttering if you think of a suitable recipient for the items that you want out of your way. Donating your old kit to the club means that it hasn’t actually gone, never to be used again. It still exists and you can get the philanthropic pleasure of knowing you donated it to a cause (and it will be the Equipment Officer’s problem now!). Thirdly, you need a reason to even start the clear out and what better reason than some new kit that needs pride of place in your dive emporium? Of course new kit won’t mean that you throw out the old stuff, not just yet, just in case… But perhaps you could clear out the kit you were wearing before the last set?

Summer is a busy time for any dive centre, and it’s almost with a sigh of relief that we watch autumn unfold so that things will quieten down a bit.  However, some summers are unremittingly autumnal as a misplaced jet stream can bring repeated low pressure systems rolling across the British Isles causing havoc and mayhem.  Many of our summer dive plans changed at the last minute as gale force winds and torrential rain made sea conditions treacherous and reduced visibility even in the sheltered bays. 
When I lived in west London, all my diving trips necessitated organising towing vehicles, booking accommodation and stupidly early starts.  I just don’t want to see 5am on a Saturday morning unless I have partied through the night to get there – and I suspect those days are behind me now.  Back then my dive trips were organised with almost military precision and planned weeks in advance.  Things are a little different now. 
When I first arrived on the Isle of Man two things struck me; firstly, how everything I’d been taught about dive planning, tidal flows and tides was completely trumped by local knowledge and secondly, how dives could be organised at 5 o’clock in the afternoon with the minimum of fuss and we’d all be in the water for 6.30.  My gung-ho “It’s not too rough really. I’ve planned to go diving so we are” attitude didn’t cut it here.  If you live with such fantastic diving on the doorstep, why have a slightly rough dive?  Wait 24 hours, let the wind drop away and have a really good dive instead.
The Isle of Man is close enough to the North West coast of England to be visible on a good day.  In fact it’s a local story that you can go to the top of Snaefell (our one and only mountain) and see 7 kingdoms in one go.  I’ll leave you guessing to name them all, but the location of the Isle of Man at the geographic centre of the British Isles means that every summer we have clubs setting out in their RIBs to travel across to dive in our waters.  And we offer visitors copious amounts of help to locate sites, plan around tides, transport cylinders, locate parts for their broken boats etc.  One of the visitors this year declared himself both very grateful and surprised that we should help him out so comprehensively and mentioned that other dive centres in the UK had been less than helpful.  Although, it’s true that we are pretty nice folks who want the best for our visitors, there are darker reasons at work. 
The Isle of Man is a limited community of around 80,000 and pretty much any diving story will end up with some link to our centre, whether it’s commenting about closing areas to dredging, helping out a fishing boat towed into harbour with their own nets around their prop or getting involved with videoing the local swimming club in training.  All diving links lead in our direction…..so it’s in our own selfish interests that we help out our visitors.  A lifeboat shout for lost divers swept away on an unexpected current or the hyperbaric chamber being mobilised for a recompression all reflects on us.  Some timely advice and guidance keeps the visitors out of the incident pit for a bit longer and keeps diving out of the news until we have a good news story to impart.
Of course, managing the exposure of diving in the local press plays a role in how we manage our diving activities too.  It’s been suggested that there are only 6 degrees of separation between any two people in the world, but on the Isle of Man that’s around 2 degrees.  Word of mouth is incredibly important.  We have to be safe and be seen to be safe, or our reputation would disappear overnight.  Doing my Advanced Driving test a few years back introduced me to the idea that ‘accidents don’t just happen’.  The same applies to diving, accidents are a culmination of a series of steps.  The advice that we freely give to visitors is the first point we can intervene to stop that series of events unfolding.  If you’re planning a trip across please feel free to get in touch.  If you run a dive centre that begrudgingly hands out dive planning information please have a think about how this reflects on the industry as a whole.  I promise you that it won’t undermine your charter service….the clubs that brought their own boats this year are booked to come and dive off our boat next year…..and looking forward to a less stressful trip. 
And in case you are wondering on a clear day you can see the kingdoms of Mann, England, Scotland, Ireland, Wales, Mann, Heaven and Neptune.

Somewhere way back in your training, you were probably introduced to the Incident Pit. It’s a fairly dramatic diagram with the words “fatal” and “death” appearing at the bottom. The concept was meant to inspire you to deal with problems early, keep control and stay safe, with the tag line “Don’t fall in.” This always seemed to be a slightly strange thing to say to divers, who are destined to fall in (to a body of water) quite deliberately. Other than encouraging you to run through your own personal risk assessment for a dive, that’s about all the standard training material has to say about pre-dive thinking.
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In many sports the technique of visualisation is used to help elite athletes achieve their potential, and there’s good evidence that it works at lower levels too. Visualisation is the process of creating a mental image of what you want to happen or feel in reality. An athlete could use this technique to picture crossing the finishing line first. For a diver there is clear potential to visualise a relaxed, in control dive and achieve a state of calm and well-being before a dive. In fact, most people naturally tend to think through and rehearse what’s about to happen to them. So quite possibly you have started to think this way already.

Sometimes these preparatory thoughts can be plagued with recurring images of past mistakes or near misses, and that’s not conducive to ensuring the success of the upcoming dive. It can be more helpful to actively direct your pre-dive thoughts and control those images in your head. And the visualisation probably needs to be more than just a visual experience. To really be successful, you would need to focus on all the senses; the rush of cold water, the smell of the sea, the feeling of pressure on your legs as you enter the water, the sound of your bubbles.

When you visualise the successful dive, you are stimulating the same regions of your brain as you do when you physically perform the same action. So, thinking the dive through, with all it’s stages, is a way of conditioning your brain for a successful outcome. Perhaps the visualisation starts before the dive, right back to the preparing your equipment. And the beauty of this preparation is that you could be doing it anywhere. Picture being on the bus thinking about packing your kit for the weekend.

What if we extend this to thinking through the different situations that may arise underwater? Rather than the scary prospect of the Incident Pit, why not challenge divers to visualise their response to common problems? What would they do if their torch fails on a night dive? It’s too easy to just say “I’d get my back up torch out”. In order to visualise it you would have to work through being able to open your BCD pocket (feel the zipper in your hand, hear the zip and feel as it bumps along the teeth), feel through the gloves for the piston clip, unclip the torch lanyard from the D ring, feel the lanyard in your hand etc. Which pocket? What else in in there to avoid dislodging? How will the torch feel in my hand? This is a far more powerful psychological technique than a glib “Get my back up” response.

For divers just starting out on their diving journey, visualisation can be an excellent way to deal with the nervous trainee. Try to remember the first time you put all your dive kit on. How tight did your neck seal feel? How restricted was your movement? These are things we all take for granted now. We have done it often enough that we barely register the sensation. I think there is a real value in talking through that first dive. This is not part of your SEEDS brief, this is so much more. Find a quiet space, sit down and step your way through the dive, start building the neuronal connections in a positive way and help boost performance.

It doesn’t matter how carefully you monitor your fluid intake before a dive, or how close to dive time you leave the last toilet visit, we have all got out from a dive ready to rugby tackle anyone standing between us and the toilet. It’s well known that going for a dive causes an increased need to urinate. There are some interesting physiological changes that come to play. Immersion and temperature changes cause a narrowing of the blood vessels in the extremities. This results in an increased volume of blood to the central organs which is interpreted by the body as fluid overload. This causes the production of antidiuretic hormone (ADH) to stop, signalling to your kidneys that they need to produce urine to lower the blood volume. So even if your last toilet visit was only minutes ago, you can quickly find yourself feeling the need to go again.
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It’s almost impossible to give an exact measurement for the volume of the human bladder as everyone’s ability to hold urine varies. Normal adult bladders hold between 300 and 400ml but can hold up to 600 or even 1000ml in some cases. The need to urinate is stimulated by the expansion of the bladder which triggers the Micturition reflex centre in the spinal cord. Most adults will feel the need to urinate when their bladder is only around a quarter to a third of its normal capacity. In normal circumstances, adults will feel the need to empty their bladder about every 3 hours, but as divers we know the effect that immersion plays.

There’s always a big debate in the wetsuit diving community about whether peeing in a wetsuit is acceptable or not. In a drysuit, the debate becomes somewhat redundant unless you have a P-valve fitted. But is there any danger to ‘holding it in’? When you first feel the need to pee, your bladder probably has quite a way to go before it’s completely full. As your bladder fills up the muscles around it will contract to keep urine from leaking out until you’re ready – just make sure you can get out of your suit fast enough!

The dangers of holding your pee are mostly cumulative, so the occasional episode probably isn’t harmful. However, if you are diving frequently and often find yourself ignoring the need to pee you run the risk of urinary tract infections, urinary retention (the muscles can’t relax even when you want to pee) or bladder atrophy (leading to incontinence). But for most people, you can hold your bladder full for a few hours without serious complications, even though its uncomfortable.

If you dive in a wetsuit, you can of course make the call as to whether you pee in your suit or not. The old saying is that 50% of divers pee in their wetsuits and the other 50% are liars. So whichever camp you fall into, just make sure you flush your suit through before you get out of the water and start to take it off, and please wash your suit thoroughly between dives.  If you’re a drysuit diver, there’s always the option of adult nappies to ensure that you can relieve yourself. If that seems a little retrograde, or as you march middle age a little too prophetic, then perhaps a P-valve is an option.

Not surprisingly there are hazards associated with P-valves too. Ignoring the issues with getting a stick-on condom or the female cup attached successfully, so that the urine does actually enter the tubing to leave suit, there are reported cases of urinary sepsis. The tubing used to connect the urine to the P-valve is the ideal breeding ground for Pseudomonas bacteria, and it only takes a small amount of backward flow to introduce those bacteria into the body. If you think rinsing your wetsuit is a bit of a faff, syringing antiseptic through P-valve tubing should give you some perspective.

​As I child I had a budgerigar called Dinsdale. Dinsdale was a pretty happy bird who would cheerfully run round my desk, leaving special presents on my homework (!) and hop back into his cage on command. He loved hitting the bell that was attached to a little round mirror and pecking hard at his cuttlefish.  Of course, he didn’t really have a whole cuttlefish in the cage with him, just the hard, bony bit.

Cuttlefish bones aren’t actually bones at all, they are a special kind of shell.  And while we are at it, cuttlefish aren’t fish either. Cuttlefish are one of the Cephalopods and they have their own family name Sepiidae. The early ancestors had a shell for protection and existed before the first fish had evolved. Modern cuttlefish don’t have an external shell but rely on camouflage for evading predators. 

The common cuttlefish (Sepia officinalis) also produces a brown ink, which can be harvested from their ink sacs.  Most of us would recognise the colour of the ink from old fashioned brown sepia photos, and that’s how the ink got its name. The chemistry and biosynthesis of ink in cephalopods is fairly complex. It is a form of the common biological pigment melanin which is the same molecule responsible for your skin developing a tan after exposure to sunlight. Who’d have thought you and the cuttlefish would have so much in common? The eumelanin in the ink sacs is also found in fossils from the early Jurassic period around 200 million years ago.

For a soft bodied animal, it seems strange that there should be a good fossil record. The cuttlebone is generally well preserved. When the cuttlefish are alive the cuttlebone is a mix of chitin (a really large structural sugar molecule) and aragonite (one of the three forms of calcium carbonate). After the animal dies, the chitin will break down fairly readily but the aragonite persists. That means that it is possible to find fossilised remains of cuttlefish that are readily identifiable and from modern catches of cuttlefish, your budgie gets a calcium supplement.

The cuttlebone has a very specific function in the cuttlefish. It’s clearly not for defence – what use would an internal bone be? Cuttlefish have a short life span, maybe only 1-2 years and during that time they have a phenomenal growth rate (up to 10 kg) so for a cuttlefish conserving energy is critically important. The cuttlebone structure is full of holes and the cuttlefish can control liquid or gas into those spaces to effortlessly control its buoyancy.

The cuttlebone is a long oval structure made of around 100 chambers, with the chamber lying at the head end being the oldest, other layers are added as the cuttlefish grows. Lying along the cuttlebone is the siphuncle, which is a strand of tissue that connects all the small chambers.  In order to add water to the cuttlebone, the cuttlefish makes the blood in the siphuncle more salty by pumping salt out of the chamber. Water in the chamber is drawn out of the chamber and into the blood by osmosis and oxygen and carbon dioxide come out of solution and make up the volume in the chamber by diffusing from the siphuncle.  So it’s not true to say the siphuncle pumps the water….more that it pumps the salt and that causes the water to be drawn out. Siphuncles rarely get preserved in fossil records but you can usually see the notches in the cuttlebone where the siphuncle used to be.
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Removing water from the chambers of the cuttlebone reduces the overall density and causes the cuttlebone to float. Cuttlefish aim to maintain neutral buoyancy and will swim up or down with the minimum of effort. In addition to this, the cuttlefish can control whether the chambers towards the head or the tail end are water filled or gas filled, making it’s journey from depth towards the surface even easier as it adjusts its trim. Next time you’re diving, be more cuttlefish, perfect buoyancy and perfect trim.