Over the weekend before last, Sarah and I completed the practical parts of the Rescue Diver course, and also the Drysuit Speciality course. We drove out to Kapellskar in the spectacular Norrtalje archipelago on the Friday lunch time aiming to get the drysuit course out of the way that day, ready for the main event over Saturday and Sunday. You have to have the drysuit proof of competency in order to hire drysuit equipment, and no wetsuits are available for hire. I've dived drysuit a few times way back when, but it was so long ago that essentially both of us started from scratch. Of course, this particular day, a drysuit was the last thing you wanted to be wearing, in a 30 degree heat. Still, we shedded our shorts and donned thermals, mid-layer and thick fleece and squirmed into the 7mm neoprene drysuits. We were cooking. Mats, our instructor, took about two minutes to get into his, and he had to jump in to cool off, as he was starting to look decidedly well-done whilst Sarah and I tried to get ourselves ready. The dive gear was different from what we're used to. First stage has a DIN conection to the tank instead of the for us more familiar yoke. There is an extra low pressure hose for connecting the suit, and the tank is made from steel rather than aluminium, and take 300 bars of compressed air rather than the 200 we've been using. The reason for this is that a drysuit gives so much more buoyancy, so to avoid having to carry 20kgs of lead on a belt, the heavier tank helps.
On our first dive we got to practice the basics, and it was amazing how weird it felt in the beginning. After we started to get the hang of the basic buoyancy control we had to practice the 'getting out of uncontrolled feet first ascent' manouver. If you over-fill a drysuit and the air for some reason gets too far down your legs, you might start to drift to the surface feet first. As you move up, the air expands further, compounding the problem. As there are no air vents around the ankles, things can get troublesome. We tried the tuck-roll move to get out of such a predicament.
After some lunch on the pier we were back in the water for more of a dive. As soon as we got deeper than a few metres I realised that I was struggling to equalise my sinuses. I normally have no such problems and I was not suffering from a cold as far as I was aware. To make matters worse, a few metres more and I felt what can only be described as an angry elephant working a sledgehammer on my teeth in my mouth. A most extraordinary pain that seemed to eminate from one of my upper back teeth and radiate out through my jaw bone. I'd recently had a filling about there, so I figured I was experiencing tooth-squeeze first hand. I always thought it was a bit of a myth, but apparently not. A tiny pocket of air is trapped in the filling, or between the filling and the tooth that contracts or expands depending on the changing surrounding pressure as you go up or down. I came very close to abandoning the dive, but once we reached our intended depth and just swam along it wasn't too bad for a while. I cursed my Bristol dentist.
As we finished the dive my sinuses made themselves known again. I knew what to expect as I took off my mask. I rinsed out all the bloody mucus - at least my sinuses should now be clean.. Back in the hut we filled out the paperwork, and we were now certified drysuit 'specialists'. I took some decongestants and headed for bed, not relishing having to do battle with tooth-squeeze for two pretty much whole days in the water. Fortunately, on the Rescue course there is very little actual diving as it were. Most of what you do is either on or near the surface, or quick jaunts to the bottom to pick something - or someone - up.
The rest of the people turned up for breakfast the next day. Our aim today was to practice the skills necessary for getting injured, panicing or unconcious divers up to the surface if they're below, and to land or boat if they're on the surface. But once in the water the first thing we got to do was to practice self-rescue - releasing cramp, out of air etc. Very useful indeed, as probably most divers haven't had to do anyhthing like that since they qualified. Then we tried various towing techniques, and trying to give rescue breaths whilst in the water. Very difficult. Raising an unconciuous diver from the bottom to the surface. Lifting an unconcious diver in various ways, also hard, especially if you and your diving buddy are of different sizes and weights. Me lifting Sarah out of the water was difficult enough; her lifting me out a virtual impossibility, which is food for thought if nothing else.
We also practiced search patterns looking for sunken treasures in the shape of sand filled drinks bottles that Mats kept chucking in, and diving equipment that us lot kept dropping when removing an 'unconcious' diver's gear.. Pretty difficult in the one metre visibility caused by six divers kicking up silt for a whole day. We retreated to the hut to eat and to lick our wounds - everybody was pretty knackered, but we suffered through the England game. Mats prepared a grand Indonesian pork curry and after a beer or two Sarah and I went to bed. At least I hadn't noticed any tooth squeeze - in fact, I think that the whole filling has blown, which is super-irritating as I now have to revisit the dentist.
The Sunday saw us diving the rescue 'scenarios', and this is the meat of the course if you like. Mats would take one or two divers aside - the designated victims - and cook up some surprise. The rest of the divers were told very little about what to expect, typically that they're out diving for pleasure when they encounter a diver with some unspecified problem which they are to try to rectify in the appropriate way. Whereas yesterday had felt like practice, suddenly it all felt very real. Sarah and I had to attend to a diver on the bottom who indicated that he'd hurt his leg. Suddenly, he signalled out of air. Sarah reacted quickly and gave him her spare, and we helped him to the surface. As we breached, he suddenly started to panic. In another scenario, Sarah was the panicing victim and won praise for her authentic portrayal, climbing on top of her would-be rescuers.
The rescue diver course, which had started a bit dull in the classroom had developed into what is easily the most fun and useful of the PADI courses I've taken. As this course has a more serious flavour than the others, I'm glad that we did it here, in cold waters with low visibility and all the extra considerations that drysuit diving entails.