Recently, while tec training I found myself practicing a simulated decompression stop. It was in a shallow (35′) lake. We each deployed our surface marker/lift bag and then ascended to 25′ then 20′ then 15′ etc. Each stop we were to practice a NOTOX gas change.
We all learned in basic scuba certification to not take the regulator out of our mouth in out-of-air situations. This is for a very good reason. The urge to breath will overcome any effort to suppress it due to being under water if you wait long enough. Keeping the regulator in your mouth will prevent you from drowning by preventing you from gulping in a big amount of water. This will give you more time to fix the problem. That additional time can be the difference between life and death.
As we began reeling our way to our first stop we began to drift apart in the murky <10′ visibility lake. Upon reaching my first stop I was out of visual range of my compatriots. This was the first NOTOX stop and gas change. NOTOX is an acronym that stands for:
- Note name and max depth for gas on cylinder you are changing too. Make sure it is your cylinder and the mix you are about to use.
- Observe your actual depth.
- Turn on valve and note pressure.
- Orient second stage, switch to new gas.
- Xamine teammates’ gas mix to make sure they are on correct mix.
I did everything as planned except for step three “T.” When I placed the second stage in my mouth and cleared it my first breath was met with complete resistance. In less than a second I had realized the problem and began corrective procedures – I was going to turn the valve on. Seems simple enough.
Upon looking down I realized that when I oriented the second stage I had twisted the cylinder to a point where the valve was pointing down, away from my face, and could not see it. It was also below my bottom gas cylinder (we were in sidemount configuration). In less than a second I realized that my first plan was going to take more time than I wanted. (Remember, I had blast cleared my second stage when I initially placed it in my mouth. I wanted to breath.) I decided to go back to my bottom gas. I had two regulators I could access but I had no hesitation as to which I was going to choose – the one necklaced around my neck. I reached for it and found it right where it was suppose to be. I was getting desperate for a breath. I already new I was going to press the purge valve on the regulator prior to and as I put it in my mouth to clear it. As I was about to do this my reflexes took control and my body tried to force in a breath.
At 25′ down the gasp of water would easily fill my lungs causing the next reflex – gagging. That would have begun the death spiral of liquid filled lungs known as drowning. The air in my bottom cylinders were just inches away. The only thing that saved me was the fact that I never took the regulator from my deco cylinder out of my mouth. It was shut off and had no gas to give me and it had no water to give me either. After that first gasp. I exchanged regs and carried on.
Scuba diving is dangerous. Even in its most tame form. It places you in an environment you are not adapted to exist in. We train and we teach skills necessary – let me repeat, necessary to survive in that environment. Simple things such as keeping a dead reg in your mouth are important to follow so you survive the simplest mistakes. Although we are taught to make diving all about “the fun” it is necessary to stress the skills to every one you teach. When it comes right down to it, scuba is not for wimps.