We’d rise early, breakfast, and dive before weighing anchor. We’d then cruise to the next reef, where we’d dive midmorning, after lunch, and before dinner. There was usually a dive after dinner as the sun set, ideal for watching the changing of the guard. Day trippers scurried for cover and the night owls emerged from their dens, and the reef took on a new look. Colours were different at night, too, obviously. Our lamps led the way, displaying the true spectrum, unsullied by depth.
You’ve never dove? Colour bleeds out at depth. The colours you do see are
altered by what spectrum penetrates to wherever you happen to be hanging. Lower
energy waves are absorbed first, so, red disappears first at about 20 feet.
Orange disappears next at around 50 feet. Then yellow at about 100. Green stays
longer and blue the longest, which is why things look bluer the deeper you go.
As long as the water is clear, that is. In murky water there is less light
penetration and things tend to look greenish-yellow. That’s not hard and fast,
either. Bioluminescence muddies the rules. So does fluorescence.
At 60 feet, red becomes black. Orange now looks drab and almost an olive-green.
Yellow holds fairly true, but green is now looking closer to yellow. Blue and
indigo are OK, but violet contrasts with black about as well as red. Everything
shifts up in the spectrum the deeper you descend, until everything is blue, and
then black.
I learned this from the photographers. Vast flashes were attached to their cameras. Even so, distance is the same as depth, so they’d swim up as close as possible, mindful of spooking their prey, mindful of angles, art, and perspective. They took great shots, but I realized that there was a trade-off; to be in the zone meant not being in the moment. Focus was gained at the cost of the panoramic. Clarity banished wonder.
How long was each dive? That depends. The answer is a slippery slope, at best. Depth cost dive time. The deeper one descended, the more volume was required to equalize. So, a dive at 30 feet could be as long as an hour, a dive at 100 feet could last as little as 10 minutes. Depends on your breathing. Gaspers don’t last as long as sippers. I was a sipper. I never inhaled while ascending. As one ascends, one needs to exhale, lest one explode. The pressure on the lungs decrease, the air within expands, and the unused air in one’s lungs remains rich in oxygen. Breathing in becomes unnecessary, exhaling on the other hand, essential. Too much depth, too many minutes dove, and one’s dive tables, one’s dive computer, limited one’s time, or extended one’s decompression stops. And if one ignored those tables and those decompression stops, one invited waivers and steel beach.
What’s steel beach? It’s a decompression day. One needs time to purge nitrogen
from one’s blood and bones, lest one become intimate with the bends, not to be
mistaken with Radiohead. I recommend Radiohead, not decompression sickness,
unless you’re a fan of joint pain, paralysis, and death.
I was not. But I wasn’t a model diver, either.
A sipper, I spent a lot of time at depth. My deco stops tended to be longer. It’s dull just hanging there, watching the timer tick down.
One day, mid-week, I hit the water. I piked, and plunged like a stone, and when
I reached bottom, my dive computer was already blinking, warning me that I
required 30 minutes of decompression at 30 feet before surfacing. The longer I
remained, the longer that deco stop was sure to be. But as I was deciding what
to do, a reckless decision in itself, a school of barracuda rose up from the
cliff wall that fell off into eternity. There had to be a hundred of them. Their
silver flanks flashed in the intense sunlight that descended to that 80-foot
depth I floated weightlessly on, the light undulating in their multitudes. I
had to get closer. I had to see each of these wonders gliding past. So, I let the
current carry me closer. I burped a little air, and I slipped down another 10
feet. Five minutes later, they faded into the distance.
I lifted my dive computer. I had about 8 minutes of air left at that depth, and
about an hour and a half of deco stop. Not particularly good math.
I waved down my partner, pointed at my gauges, and indicated that I was rising. I inhaled deeply and began to rise. And as I rose I began to exhale. I spoke a light and slow “ahhhhh,” just enough to purge the ever-expanding air in my chest cavity. That slow “ahhhhh” would allow me to rise up the next 60 feet without ever needing to inhale again, saving air for my decompression.
But when I reached 60 feet, I realized that I didn’t have enough air for the two stops I needed. I continued rising, my exhaled bubbled rising marginally fast than me. At 30 feet, I had 30 minutes of air left, and a need of 60 minutes to decompress. I waited. With 5 minutes of air remaining, I rose to the surface, breaking the top with 1 minute remaining. My computer rebelled. It flashed. It told me that I was not done with decompression yet. And when I broke the surface, it froze, and would not release any information except a countdown, the time required to purge all the nitrogen from my system. I could not dive again until I was clean.
That would be in 24 hours. Until then, I was stuck on the boat, forbidden to
dive for my own safety.
Steel Beach.
That evening, the sunlight waning to a rich golden hue, I settled in to supper.
I bit down on whatever soft morsel I was eating. And my tooth exploded. Not my
actual tooth. The veneer that covered it.
I heard a high pitch squeak of air, and a pop, and the porcelain cap was in
pieces in my mouth.
A little pressurized air had made its way behind my tooth when I was diving. It was still trapped there when I broke surface. And it blew apart my veneer when a little pressure was applied.
Now imagine your joints were that tooth, the pressure trapped in there.
The Bends.
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