Written by Nick Clifford – NHDC Divemaster
Molnar Janos-barlang – Intro
In January I went on a cave diving trip in Hungary, diving in the thermal springs of Budapest, Molnar Janos-barlang. The last day of diving was the most technically demanding dive I have done so far! I learned what stress in diving for me was, and how to handle it.
As I’m certified for multiple stage cylinder cave diving I wanted to make the most of it and do a big dive as it was the end of the trip. The plan was to go to the furthest mapped point in the Molnar Janos cave system. The dive team included myself, my buddy Simon who is a very experienced cave diver, the guide on CCR and 2 very good German CCR divers.
We discussed the route we would take, and it became apparent that this would be by far the deepest cave dive that I had done. It involved carrying 4 11ltr aluminum gas cylinders, plus a 7ltr tank holding 100% oxygen for accelerated decompression on the exit. We would be reaching a maximum depth of 42m. We were planning a penetration of roughly 800m. Our predicted deco time around half an hour, total dive time of 2 hours.
Molnar Janos-barlang – Apprehension
I had done 800m+ cave dives previously but never down to 42m and I had a slight feeling of apprehension. Never the less I knew what I needed to do. I was comfortable with my training, abilities and with my equipment set up.
Molnar Janos-barlang – The plan
The plan was to breathe 1 of the stage cylinders containing nitrox 32% down to 32m, switch to back gas of normal air to get through the deep 42m section. This would lower the oxygen content and preventing PPo2 toxicity. This deep section would take 3 to 5 minutes to pass. We would then switch back to 32% when we were able to ascend up to 30m on the other side. We had to do this on the way back as well and would mean a total of 4 gas switches throughout the dive including the 100% deco bottle.
The start of the dive went smoothly, strapped with gas cylinders, pre-dive checks done, we descended. After about 35-40 minutes of swimming, we came to the 32m section where we had to switch gas. After switching to air we descended down this crack in the rock and entered this black, silty room at a depth of 42m. I don’t know what came over me, but I started to over think where I was. A long way into a cave, deep down in the black, poor viz and already with 15 mins of deco on my computer. My heart rate and breathing started to increase. ‘No not here!’ I thought I could feel myself on the verge of panicking (the worst thing that can happen in a cave). I felt like a child again in what was very much big boy diving!
Molnar Janos-barlang – That English guy
I was considering aborting the dive before my head went past the point of no return. But then I remembered the 2 German divers behind me, cracking jokes about Brexit all morning. I thought ‘I can’t be that English guy who got frightened and ended the dive!’. I took a few breaths… ‘Come on pull yourself together, you can breathe, all your equipment is working fine, you’ve got loads of gas, you’ve got this! Get rid of those stupid wimpy thoughts!’
It must have lasted about 30 seconds, but it gave me a rain check on how panic can creep up unexpectedly.
Molnar Janos-barlang – The take away
I spoke to Simon after and said I had a little wobble in there did you notice my breathing rate went up? He said no, but that he also was not so comfortable at the deep section. We came to the conclusion that because we had switched from breathing nitrox then switching to air for the deep part, we had sharply increased our nitrogen intake. We could have been feeling the effects of nitrogen narcosis. The next dive I went for a trimix fill to prevent this.
Stress whilst diving can happen to any level of diver. You’ve just got to think logically and break it down, can I breathe? Is there a problem? Can the problem be solved? If it is just nerves in open water diving, the surface is not too far away.