Narked at 30m?
Safe diving and Mark Andrews - the two don't go together like a horse and carriage in the minds of divers, but when a sceptical Brendan O'Brien went on a weekend course run by the deep diver, he was to undergo an experience that would upset all his previous certainties
"Do you think you're safe diving on air to 50m?" That was the question posed by Mark Andrews, the world record-holder for deep air diving, at this year's London International Dive Show.
While the audience pondered it, he continued: "If you think you're safe, I'm telling you that you're not. You all suffer from nitrogen narcosis at those depths and you're on thin ice. If you don't believe me, I'll prove it to you."
Many people who attended the show believed Mark's deep-diving antics to be foolhardy, verging on the suicidal. Putting that to one side, does he have a point? How safe are we diving on air to 50m? Or even 30m? Have we become too complacent about depth and the effects of narcosis?
Mark is preparing to run an extended-range recreational diving course through the Professional Scuba Association (PSA). It isn't about learning how to dive to record-breaking depths, he stresses, but how to dive deep safely and at the same time cope with the effects of nitrogen narcosis.
And what does he mean by deep? The initial course is to depths not exceeding 30m, he told me.
Now I've carried out hundreds of dives to that depth without suffering from narcosis, so I decided to go along for a preview of the course and see for myself.
The location was Dorothea in North Wales, a flooded quarry used regularly by Mark and his team for practising deep air diving techniques. The waters are cold, dark and exceed 80m only metres from the quarry edge (the deepest part is at about 107m). These, I was told, were perfect conditions for the course.
Joining me were PADI Divemaster Kevin Rose and BSAC Advanced and trimix diver Lee Mason. They were equally intrigued by Mark's claims.
After being told again that our maximum depth over the weekend would be 30m, Mark went on to say: "I will try to make you go deeper. It's up to you to say no, but I know you'll be so narked you won't be able to. You will go deeper than you planned to go."
The PSA was founded by Hal Watts, owner of Forty Fathom Grotto in Florida. He taught Mark to be an extended-range diving instructor, was once a record-holder for deep air diving and credits himself as the diver who introduced the octopus second stage and the phrase "plan your dive - dive your plan."
He believes that the PSA's 100 per cent safety record is down to the techniques it advocates.
As the lectures continued, I started to realise that my diving theory was not up to scratch. I hadn't been planning my dives, simply relying on my air-integrated computer to do all the work for me.
Now it was back to the drawing board.
The mnemonic DATA stands for Depth, Air, Time and Awareness and underpins how the PSA plans and executes its dives. A deep dive could be to just 25m, we were told. Combined with unfavourable conditions such as cold, darkness and any unplanned occurrence, diving at this depth could bring on narcosis.
We looked at what happens when dives don't go to plan. Were we confident in our ability to deal with a range of emergencies? How confident were we in our buddy's ability? If we believe our buddy is not up to saving us in an emergency, whether from lack of fitness, experience or knowledge, the PSA's advice is not to dive with him or her.
The Air and Time parts of the mnemonic refer to the strict planning and execution of a dive, taking into account all the variables. As gas management is an important part of any dive, we spent time working out how much air would be required at each stage of our forthcoming dives. On a PSA dive, surfacing out of air is not an option.
Basic equipment is another PSA priority - if you don't have what you need, don't dive. It seemed I had got into the habit of treating essential items as optional extras.
I had forgotten my knife, thinking it wasn't important for a quarry dive. It would have been useless against some underwater obstacles anyway, said Mark - the PSA recommends that industrial scissors be taken as well as a knife. I didn't have a set of dive tables either, or a watch in case of computer malfunction.
Some of the equipment I had brought gave cause for concern. My gloves were old and full of holes in the fingertips, which could cause cold to affect my hands. Such a distraction could be the catalyst for narcosis.
My hood was ancient and the neoprene had probably lost some of its thermal properties. I had become complacent, not attaching enough importance to some items and ignoring the upkeep of others. Looking around me that weekend, I saw that I wasn't alone. Perhaps we all need a periodic kit inspection by another qualified diver?
We looked at the rest of my equipment. I was unaware of my BC's lift capacity and whether it was capable of bringing up two divers from beyond 40m. Fortunately it was, but how many of you went into that when buying your BC?
My regulator and octopus were of a high-enough performance to enable two divers to breathe off them at up to 50m. The PSA trains that the primary reg-ulator is handed to the buddy in an emergency, because the last thing you want is a panicking out-of-air diver fumbling around for your octopus or trying to snatch your regulator out of your mouth. Was my hose long enough to enable me to do this? No.
How many of you have bought a cheap regulator believing it will do as an octopus? Think again: you might have to breathe off it at 50m.
Have you ever checked whether your first and second stages and octopus could function effectively with two people breathing off them at 40m-plus? If you have, could they still do it? When was your regulator last serviced?
My 15 litre cylinder was big enough to enable me to carry out dives to 50m. I had always planned my dives to cater for one diver, not two, but what if another diver needed to share that cylinder? I had a pony cylinder at home which I rarely used - perhaps I should consider using it all the time.
We carried on looking at emergency procedures, techniques, leak checks, surface support, a common understanding of all signals together with some new ones, and the procedure for checking our own and each other's air.
"If one person wants to abort the dive for whatever reason, we all abort it without question," said Mark after the lectures. "And I mean without any question. There's no room for gung-ho peer pressure in extended-range diving."
I cast my mind back to all those club dives on which people were forced into situations in which I knew they weren't really comfortable. We had got away with all the "good-natured" jibes then, but how many over the years haven't?
The next day we carried out a warm-up dive to 25m, so that Mark could see how we were in the water. After a long surface interval it was time for our 30m dive.
The plan was for Mark to buddy with Lee while I accompanied Kevin. Lee, convinced that nitrox would overcome any narcosis problems at this depth, would be allowed to use nitrox 32.
We would descend as a group down a 45m line to 25m, where we would level off, check our equipment and establish our buoyancy. Only when we were all ready would we proceed to 30m.
After four minutes we would all make a note of our depth. After six minutes, as a safety procedure, we would note our air pressure and that on the others' gauges. Then we would monitor only our buddy's air pressure, doing this at two-minute intervals.
We would leave the line for a wall about 10m away and after 15 minutes begin to surface. To demonstrate our awareness during the dive, Mark would ask us to remember something by using a specific signal. Also, at any point in the dive, we could be asked to show him where north was.
We had calculated our safety stops for a 15-minute dive to 30m as well as for the eventuality of us exceeding 15 minutes and going deeper than planned. Mark kept reminding us that under no circumstances should we go deeper than 30m, but that he would do everything he could to get us to do so. If he did, we were to give him the signals to ascend back to 30m.
I had expected that to demonstrate the effects of narcosis we would be writing our names backwards or solving puzzles. However, there was nothing in our dive plan that as divers we shouldn't be doing anyway - just monitoring depth, air, time and awareness, putting DATA into action.
I had gone through the dive in my mind and had prompts for all the information I would be writing down on my slate. I was convinced everything would go to plan.
That was the plan. This is what happened...
After the swim out and spending some time to relax, we started our descent. The line seemed cluttered with four of us on it but we had allowed for that. None of us would go deeper than Mark and we would all hold the line beside our buddy.
After 20m, Lee dropped below Mark and let go of the line, but he got hold of it again for the levelling-off at 25m. At four minutes we all logged our depth of 28m (it had seemed a fast descent, but it was only 7m a minute).
At six minutes we were at 30m and it was time to show and record each other's air. I had already written the names on my slate, so this should have been easy.
Apparently not. I wrote Mark's air down in my column, mis-recorded my air as 116 bar instead of 166 and didn't manage to read Lee and Kevin's air. By this time Kevin was only half-heartedly returning signals. I knew that not giving bold signals was one of the first indicators of narcosis, but I ignored it. He was OK, I thought.
Mark looked down and pointed at something below us, gave the signal to descend and began to drop further down the line. I joined the other three until 32m, when I remembered what he had said he would do, but the others followed him down all the way to 39m.
They stayed below me for a couple of minutes; Lee and Kevin hadn't even noticed my absence. It was only when Mark indicated for them to look up that they saw me trying to catch their eyes and giving them the signal to ascend.
It had been that easy for one diver to get us to break from our dive plan. In less-controlled conditions, the consequences could have been fatal.
Back at 30m, Kevin still seemed a little unsure of himself. I knew that I should have given him the signal to ascend a few metres, as he was probably suffering from narcosis and this would clear it, but I did nothing. I still felt great, confident that everything was going well.
Mark indicated that we should all fin over to the wall. Kevin didn't return the signal, but I did and wanted to go. I let go of the line and started finning. Kevin held onto the line as I indicated for him to follow me. His OK signal was more of a wave than anything else. I remembered thinking that he was probably narked, but that was OK, I would go anyway. I'd still be able to see him, though only just.
I knew that what I wanted to do was wrong but I did it anyway. It was like that feeling you get when drunk. Mark dealt with Kevin, because by then I wasn't bothered. Lee was already by the wall and I joined him. After a minute Kevin rejoined me. By now we were more than 10 minutes into the dive.
I soon remembered that I should have checked Kevin's air, so I did. It was at this point that Mark gave me the signal to remember something, and then went on to point to his wrist compass. The signal was clear, but I misread it. I looked at my own compass and showed him where north was. He gave me an OK signal which I didn't return. I looked again at my compass and told him where north was again - I have no idea why!
Then I thought for good measure I should look at my air pressure. I looked but had no recollection of the reading, though I remember thinking that it was OK.
One minute before 15 minutes we were supposed to give a signal to begin to surface. After looking at my gauge numerous times and not sharing its readings with Kevin, or really remembering what information was being displayed, I suddenly realised that we were 17 minutes into the dive. At this point we all managed to share signals to surface.
I still thought the dive was going to plan - what's a few minutes? I saw Lee below me at about 35m having problems with one of his hoses, but Mark was with him so it would be OK, I'd stick with Kevin.
We left Mark and Lee behind - that was how easy it had been to become separated.
We carried out our back-up decompression stops as planned and, by a happy accident, came across Mark and Lee. It was only as we got shallower that I realised that the dive had not gone smoothly - it had been a shambles.
At the surface we all began to realise this and wanted to get it off our chests. Mark told us to save it for the debrief.
After dekitting and warming up, we discussed everything that had happened, the effects and what the possible consequences could have been.
Kevin: "There was no doubt about it, I was narked. I knew my signals were poor and my breathing was heavy. I knew that I should have indicated for us all to ascend but didn't. Next time I will be more aware and will ascend. I do get narked at 30m, only I'd never realised this before.
Lee: "I totally forgot about my skills and became preoccupied by my air pressure. Also, I can't believe how easy it was for Mark to persuade me to go deeper than our plan. If this wasn't being narked, I don't know what was. I need to practise my skills more until they really are second nature. Only then will I be really ready to go deep again."
I had been narked on this dive. I was prepared to do things or omit certain drills at a depth of only 30m. I had ignored the plan, ignored my buddy, misread my gauges, failed to read signals correctly from my buddies and had, as Mark promised me I would, gone deeper than planned.
I cast my mind back to a warmwater dive I had carried out a couple of years ago. We had planned to go to 35m and ended up at 53, with my buddy trying to coerce me into entering a small cave. I had my computer and thought that I was OK. I hadn't been, I'd just been lucky.
Only now I know this. I'm more aware of the effects of narcosis and in the future I'll be less prepared to act on them.
Mark Andrews is awaiting final HSE approval and hopes to go ahead with his PSA courses next spring. For details call 01252 815444.
Appeared in DIVER - October 2000