The dive was at the North West Emergency Recompression Unit, at Murrayfield Hospital in the Wirral. A bit of a drive but the only alternative was to waste another day of the weekend messing with the grownupsac server.

I collected Jeremy from his house on the way North and we zoomed up in minimal traffic, and arrived some 2.5 hours early, so dropped in to see Jo. She took us to the Boat Museum in Ellesmere Port to look around the raised U-boat that they have there.

Sadly, the raised U-boat is not at the Boat museum, but at the historic warships museum instead. So, we looked around a collection of rotting barges instead :-/

Then it was on to the Pot!

First we got an introductory lecture. The chap explained what they do in the chamber (only 10% of their work is diving injuries). He showed us some fairly gruesome photos of folk they've fixed up in the pot. He did a bit of a sales-spiel on why we're better off with a few specialised recompression facilities rather than having a recompression chamber at every dive site. He then went on with more specific diving-related stuff, going into some physiology, top tips on how to reduce your chances of getting a bend, and why there are better alternatives to using 100% o2 to treat bends victims.

He also showed some photos of Fred Buyle and Tanya Streeter doing simulated deep freedives inside the pot! The chamber is mostly filled with water, then pressurised, and they get to practise breath-holding at depth while only being a foot or so below the surface. Very cool.

Then it was down to the chamber. We were split into two groups, one of eight and one of seven folk. I went in the second group.

The first group went in and got blown down to 50m while we watched them get more and more pissed as they got deeper. I started chatting with the instructor-chappie about deep stops. He asked me if I'd ever had a doppler test (I haven't), so we went off and he stuck this gadget on my left shoulder that enabled us to listen to my blood wooshing round me. He got me to squat down and stand up and he repeated the test, again you could just hear the blood pulsing round.

Meanwhile the other group had completed their dive and it was our turn!

We climbed in and the door was closed and they started blowing us down. There was much noise of the air entering the chamber and we had to constantly clear our ears with the increase in pressure. This continued for some time, when abruptly the pressurising stopped and the voice came over the intercom "you're at 6 metres. Is everyone ok?". 6 metres? It had seemed that we'd been going down for ages and we were only at 6 metres! We called out that we were ok and the descent continued.

With only one other pause (to allow someone to clear their ears a bit more slowly) we were then taken down to 50m. It was hugely hot on the descent and most of us were sweating buckets.

At 50m you can clearly feel the effects of narcosis. This, coupled with the fact that everyone's voice goes all squeaky because of the high pressure, leads to much hilarity. Curiously, although most folk sounded completely different to normal, Jo's voice sounded exactly the same as it does at the surface. Some of the BUDC folk tied some knots, fairly successfully it should be said. My computer said we were at a depth of 50.5m, which is pretty close I think.

We stayed at 50m for a few minutes enjoying the narcosis. Then it was time to ascend. First we had to dress up warm (we were still very hot from the descent) and cover ourselves with the supplied blankets. Just before we started the ascent my computer went into stops.

On the ascent the air immediately cooled down, and a light mist formed in the chamber. You could feel the excess pressure escaping from your ears. The cold air was a blessing as I was still waay too hot.

We were taken back to 6 metres, where we stopped for 4 minutes. My computer cleared its stops during this. Then we were brought to 3 metres for a further 7 minutes stops, and then we were brought back to the surface. Total dive time of about 30 minutes.

Two of the BUDC folk from the first dive had come out with pain in their wrists and so were put back in for a second dive in the other chamber. They came out of this with no symptoms at all.

After the dive I had another doppler test. He stuck the gadget back on my shoulder and again you could hear the blood pulsing round. But it sounded just the same as before the dive! I immediately concluded that I was immune to DCS. He then got me to squat down and stand up like before. This made the doppler sound completely different. Along with the swoosh of blood there was a fairly constant (and loud) background noise that sounded a bit like a howling gale. This was all the bubbles in my blood coursing around. The chap smiled at me and said (in his scouse accent) "you're Aero, you are" :o)

So, a very enjoyable day out, even if the drive there and back was a bit mad. If you get a chance to do one of these I recommend you take it.

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