If you think about it, the idea of adding helium to a compressed breathing gas mix seems pretty ingenious. It has a super low atomic mass so it’s far less dense than oxygen and nitrogen, it’s an inert gas, it’s easily soluble in the body which makes it good for perfusion, and it makes you talk funny under water. Seriously it’s the most amazing gas I can think of. It’s also becoming hard to get.
I woke up feeling pretty excited yet anxious. Today would be the first real Tech 2 dive and a milestone of sorts. The consequences for screwing up were also very real now. We planned to go back to Willis Point and do 30 minute bottom time at 150′. We’d be using 21/35 as our bottom gas, which is a gas mix of 21% oxygen, 35% helium, and the rest is nitrogen + the other trace amounts of various other gasses; “Trimix” as it’s called. Guy also mentioned that if we didn’t screw up the dive, we’d practice the unconscious diver recovery…mid water. But more on that later.
Just like the day before, Jon and I piled into the car with all our gear and headed south. It was still raining and dreary but I had made it this far in class so I felt like I was over the hump. I could almost imagine myself at the end of the class on the last dive breaking the surface after having done my deepest ever dive. I imagined the feeling of being done and heading home, feeling accomplished. It was 3 days away, I thought and if I just kept working hard and paying attention, maybe I’ll get there. I was really enjoying the class so far and was feeling proud that I made it even to day 4. As I mentioned earlier I really didn’t have any expectations of passing the class. This was a completely hostile, cold, and unfamiliar environment compared to my warm and comfy caves back home. I was completely out of my element but loving it at the same time.
We arrived at Willis Point in about an hour after leaving Guy’s place with minimal traffic and began to get the gear to the water. It was cool to finally see that 150 MOD bottle. I’ve done plenty of Tech 1 dives in caves and a few in the ocean. So this wouldn’t be my deepest dive by any means (not that I’m a depth chaser), but this was meaningful because Guy trusted us enough to execute the dive. Like when your parents hand you the keys to the family car at age 16 after you just got your license. Or when you’re a kid and you get your first 22 (It’s a gun reference, remember I’m a country boy who got his first firearm at age 6) There is an increased sense of responsibility; a coming of age so to speak. I think unless we seek out things like tech diving or maybe another analogy would be to learn to fly a plane; we get less and less of these opportunities as adults, which is a shame. So at 41 years old, I was feeling a little bit like a Kid again.
Jon and I did the drysuit/gear donning dance, taking turns huddling under the hatch of the Rav in the rain, desperately trying to conserve any and all dryness of the undergarment, while we geared up. Once were were in our gear, we did our GUE edge and headed down to the water. Today Jon would lead the dive which I was fine with, but this meant If I made it to tomorrow alive or was still allowed to participate in the class; I’d be leading the deeper 200′ dive. The tech 2 experience dives incrementally take you deeper until the final day where you do a 250′ or so dive (often a little shallower for safety and logistic reasons).
The mood was a bit more relaxed today and I still didn’t know if Guy was going to hit us with any failures but it seemed like he wouldn’t. I suppose he was satisfied with our performance and to be honest, I’m not sure if instructors are allowed to simulate failures below 100′. So in my mind I half expected the shit to hit the fan when we got up to the 70′ stop. It does seem like creating failure scenarios at say 150′ would be foolish to do to students in the event that you have a significant decompression obligation with a student who might lose control and fly to the surface like a titan missile. Though the other side of the coin is that we could have handled it (Jon and I) so the risk vs the reward of such a thing isn’t worth it from an instructor liability stand point. At least this is how I’d make sense of it.
We descended down past the “submarine”, down past the 100′ depth that we stopped at the day before, and now we were in new territory. There was a noticeable thermocline and the water was even more spooky and dark than yesterday. We were technically in the ocean so any number of creatures could appear out of nowhere at any moment. I half hoped I’d see something amazing like an Orca or a six gill shark as long as I lived to tell about it. At 150′ the bottom appeared, at least what looked the bottom (maybe it was a significantly wide ledge). I believe the site drops even further than that but I don’t recall. We began to swim along the wall, similarly to the day before. I was really enjoying this, just focusing on executing the dive; though I couldn’t help but be on edge waiting for the bubble gun. It’s weird when you get past that point in class where the failures stop, but you still have post traumatic stress expecting it to happen. This is one difference in the Tech classes vs Cave. The failures go all the way to the last day in Cave class but in Tech the experience dives typically are just dives with a mentor as far as I know. So in that respect, one might say that the tech classes are “easier”. However I think one of hardest aspects of diving is the ascents which makes cave diving like a walk in the park compared to tech diving.
Jon and I swam along the wall, lazily poking around looking for wildlife in the cracks and crevices’ until the turn time was reached and we made our way back to where we had come in. No scary monsters came lurking from the depths unfortunately, so we began our ascent and did our deco in lock step with the plan we made. Timing off the bottom was good and we executed out bottle rotations well. I was cold but it was all coming together; I felt like a tech diver. We had a small deco obligation at 20 feet so Jon and I looked for critters on the bottom while we passed the time. The hardest part was over; now it was just waiting the 15 or 20 mins in 52 degree water to decompress at 20′.
Decompression or “deco” as most of us call it is always a mental game. I think a lot about the outside world and while it’s peaceful, it also leaves you alone with your thoughts, so looking for critters, playing sudoku, or some other means to occupy your brain is a must. That is unless you just like to think, which I do a lot of. Interestingly 20 minutes goes by in the blink of an eye when at home but on deco it’s a freaking lifetime. Let’s not talk about hour long deco or more; it’s almost torture. I’m dreading and looking forward to the day when I get a chance to do real big boy and girl deco with TTS of 4-6 hours.
We finished our deco clean and I was definitely cold, but Guy wanted Jon and I to practice our unconscious diver recovery. This is a drill that simulates your buddy having an oxygen toxicity seizure while under water; and this is a very real risk in tech diving. Breathing too much compressed oxygen at depth can cause you to effectively lose control and go “unconscious” under water. What’s worse is that by some accounts, the “unconscious diver” is actually fully aware of what’s going on but cannot move or communicate. I imagine it would be like that dream where you are being attacked and you try to scream or fight back but you can’t. Apparently as part of the sleep cycle; our brain shuts down the body, in a sense making us paralyzed as we go to sleep. This is probably a good thing, otherwise we’d all be beating the shit out of each other in bed. Many people have experienced the “unable to scream or fight” nightmare at one point in their lives. Mine was when a couple of aliens tried to abduct me in my room as a kid. It’s probably happened more than that, but this is the only time it comes to mind. In hindsight I suppose it might possible it wasn’t a dream, but let’s not go there. I also used to have a reoccurring nightmare about the Hershey chocolate milk commercial from the mid 80’s where the Hershey cows came down on parachutes to deliver chocolate milk to eager kids waiting for the delicious chocolaty goodness. Only in my dream it was some apocalyptic nuclear holocaust and the cows and parachutes were on fire as they floated slowly towards the scorched earth. I was probably 5 or 6, so explain that one?!?
The unconscious diver recovery is where you suddenly find your buddy unconscious or unresponsive. It’s truly nightmare fuel along with being deep in a cave and losing the line in a silt out. You, (the rescue diver) need to try to safely get your buddy to the surface while keeping the regular in their mouths (if it hasn’t fallen out yet). It’s likely the will still be breathing and it is possible to save them if so. To execute this recovery properly one must climb onto your buddies back, hooking one arm under there valves to maintain control of the regulator and keep the airway open, while the other hand (the left hand) controls the wing and drysuit of you and your buddy. Then effectively ride the unconscious diver to the surface in a very controlled way such that you can maneuver them (like in the case of a cave) out of danger. The rescue diver must manage his own wing and drysuit as well as the buddies and perform the necessary stops. You can’t just mash their power inflator button and send them rocketing to the surface, hoping for the best. This is a bit easier when you can dump ALLL the gas out of your wing and suit in preparation for the recovery. I’ve done this drill plenty of times and have gotten pretty good at it with one exception: The unconscious diver was always on the “floor”. This means that you could climb on their backs and dump all the gas you have, then managing their gear and suit is great deal easier.
In the case of recovering a diver mid water, you have none of the luxuries above which makes it an order of magnitude harder. Jon and I took turns playing “dead” while mid water and we both tried to do the recovery. After a long deco with cold hands and feet it was a huge challenge. Though props to both of us, neither of us let the other “cork” and we were both able to manage some level of control as we made simulated stops up to about 10 feet before descending back down to try again. I think this is a relatively new skill being taught at GUE (at least at the time) and I can tell you it’s hard, really really hard.
After saving each others lives a few times, we exited the water. I was feeling confident and happy that day 4 was now over. We all quickly geared down and headed back to the Red Barn for another delicious sandwich. Much like the previous day, I ate mine on the road as we made our way back North to Duncan. Jon and I discussed the day naturally and both of us remarked how difficult the mid water recovery was. I was feeling pretty tired and despite having a lot of fun, was ready to go home.
We arrived back at Guy’s place with out incident, and began the usual gear clean up, hanging dry suits, charging batteries etc. Guy knew I was super cold and my little 9ah battery pack wasn’t cutting it, so he loaned me one of his larger battery packs for the next day. He also loaned me a brand new heated BZ200 and said if I pee in it I have to buy it. I finished my chores and had some dinner while I did the homework for the day, which was typically answering questions on the modules and planning the next dive. Tomorrow would be 25@200. Guy told us we’d be on a boat which sounded awesome, and we’d get real deco, a real Tech 2 dive, and I was excited.