For years my standard has been "show the SPG". I want to see it. I'd gotten used to seeing it. Never really thought about it. I'm aware that a lot of people flash the hand signals, and have learned to adapt to the conditions. Or so I thought.
Last December, night dive to about 100' at Redondo Beach in SoCal looking for a squid run. I'm with a "random club buddy". Someone I didn't really know, had never done a dive with. He's in the dive club, and no problems were expected.
His pre-dive check seemed complete, and he just seemed to have more dives under his belt than I (at my 100 or so). He was AOW, I was OW (but with plenty of experience at Redondo at night).
We agree to dive until 1500 psi, and then start for the surface. We will do a 1 minute "deep stop" at 1/2 max depth, or 50'. Note the ambiguity in this plan, it will bite us in the tushie later :11:
We dive, and he looks around squid, and lobster. I decide I will be the attentive buddy on this dive, and simply follow him around while keeping an eye out for squid or lobster).
After a while, he comes up to me and kneels on the bottom, and flashes his hand at me "open hand-closed hand-open-closed-open-closed".
I see 5-0-5-0-5-0-5-0. I have no idea what he meant. I shrug, and he takes off and starts swimming. Not quickly, just calmly and "normal".
I think "well, whatever it was, it apparently wasn't that important. (note, MY failure here.) Maybe he was repeating a compass heading? A preferred depth?
I swim after him. He slowly turns in an arc toward the right.
After a few minutes he stops, looks at his gauge again, turns back to the left and keeps swimming. I think "Ok, he wants to follow a course.
Then he starts turning to the right again, and I think he's still looking for lobster. My air is still showing plenty, I'm an air hog, he seems calm enough, and is not stopping to show me his air gauge. He is looking at it now and then, and if it was a problem, he'd show me, right?
So we keep swimming along.
By the third time he stops his right hand turn, and again looks at his compass, and turns around and starts swimming again, I start to think "What the ----?"
Then he starts a right hand turn again and I realize " He has no clue where he's going." I rush up and grab his leg, and he turns to me and (finally) shows me his gauge. <500 psi, at 100 feet.
His hand signal was intended as 5-5-5 = 1500 psi.
I had always learned that 1500 psi is 1-5 or 1-5-0-0. Sure, I have a graduate degree in math, but why are you making me add?
I had never seen his method before.
He had intended to follow the bottom contour up from depth (hence his swimming along the bottom). My standard way to end dives ar Redondo is to go UP, doing mid-water stops, and then head back on the surface. I like the upper layer of biolum at night. I had only been diving there with people who do that.
Since he wasn't going up, instead staying on the bottom, I thought everything was just dandy.
And his "wandering" to find more lobster - he was so distracted by his air gauge he kept losing track of his compass (and the direction to shore).
We got to the surface ok, on my air. Did the 50' stop and all, but I learned several lessons.
1. More detailed dive planning. Not just that you will end the dive at some point, but exactly HOW it will be ended.
2. I also keep much closer watch on my buddy's air, to the point of being annoying sometimes, but I WANT TO SEE THAT SPG! Maybe not every time, but at least until I can "guess" what you have before I see it. From then on, the checks are just to confirm what I already know. At this point, hand signals are acceptible.
Now, back to the main purpose of this post, and the thread.
I also go over hand signals before the dive. I've done some homework since that dive and have found there are 13 different hand-signal methods for numbers - some one handed, some two handed, some inverted, some sideways, some sequential, some parallel. Some are similar to others with seemingly minor differences. I now make sure we are on the same method. I ask them to show me 1800. That is a great number for testing, as a lot of the subtleties of the different methods will be seen there.
A long post to get to this conclusion, and there were other failures during the dive, but at no point until the very end did it seem anything was amiss, and simply understanding his hand signals would have fixed that.
It was a good experience in one other sense. After thinking there has to be a better way, I started looking into other dive practices, and that's how I first heard of DIR.
