2 Dive 4 Scuba

7 Secrets to Better Diving

If you want to dive better and safer on your next trip, it's time to shake things up a little. Tomorrow morning you can be a more confident, more relaxed diver. You can stretch your tank longer, maximize your bottom time and feel sharp, alert and full of energy for the whole day. Tomorrow you can cruise up and down the water column as easily as a fish and forget about getting lost: you'll always know where you are and how to find the boat again.

In your dreams? No, it's real, if you follow these seven rules.

RULE #1: Dive Solo

Well, dive as if you were solo. We don't mean you should abandon your buddy mid-dive. By all means stay close to your buddy and be ready to help him. But, as far as your own safety is concerned, pretend he's not there--or won't be when you need him, which is often the case.

In any emergency, your closest and most dependable rescuer is you, so become a self-reliant, as-if-solo diver. It may require some different equipment. You may want your own completely redundant air source, like a pony bottle, instead of relying on your buddy's octopus. You may want several cutting tools instead of just one, mounted so you can reach at least one with either hand.

But more important than gear is anticipating what could go wrong and rehearsing how you would deal with it alone. If the wheels come off your dive plan, you'll start thinking through and acting on your problem immediately instead of wasting time looking for someone else to rescue you.

By thinking solo, you'll plan smarter, too. Ask yourself, "Would I do this low-vis, high-current dive solo?" If not, maybe you shouldn't do it at all.

RULE #2: Be Lazy

Doing everything in slow motion will stretch your air supply. You ought to kick your fins, move your arms and turn your head as though any motion were almost too exhausting to attempt, because it is. Water is 800 times more dense than air, as you've probably heard, oh, 800 times. Moving an arm or leg in water requires a lot more energy than it does in air. Energy is fuel plus oxygen, so the faster you burn energy the faster you empty your cylinder. It's that simple.

Slowing down conserves energy and air because speed is very expensive. For those who've forgotten physics class, the energy cost is proportional not just to the speed but to the square of the speed. Swimming twice as fast requires four times the energy. Swimming three times as fast requires nine times as much. And the converse is true too: if you cut your speed in half, you need to burn only one-fourth as much energy and one-fourth as much air.

It takes a conscious effort to move at Tai Chi speed, but practice will make it second nature. The payoff is bragging rights over your air-hog buddy at the end of the dive.

Be lazy out of the water too. Take off your tank and weights as soon as possible. If a deckhand offers to lift your tank for you, let him (and tip him later for it). Sit down as much as possible. You'll be less fatigued at the end of the dive, therefore more enthusiastic for the next one.

You'll also be more alert if you've been lazy. When you're tired and running on empty, you don't think clearly. So be lazy with your body in order to stay alert with your mind.

RULE #3: Hold Your Breath

What we're advocating is to reverse your normal breathing pattern from inhale-exhale-pause to exhale-inhale-pause--the pattern many experienced divers adopt naturally over time. The pause while your lungs are full of air allows more time for gas exchange, so you take in more oxygen and dump more carbon dioxide with each breath. Therefore, you need to breathe less and will get more cycles out of your cylinder. It only takes a pause of a few seconds after each inhale to make a significant improvement in your breathing efficiency.

Telling you to hold your breath during that pause gets close to the fundamental no-no in diving, so let's be careful here. What you certainly don't want to do is to hold your breath by closing your throat and relaxing your chest against it, because that makes your lungs a closed container. You risk an embolism if you ascend with your throat closed because the expanding air has nowhere to go. It is safe, however, to hold your lung expansion with your chest muscles instead and keep your throat open. Now, expanding air can escape up your throat so there's no risk of embolism.

Instructors don't teach this breathing technique because they're afraid students will become confused and close their throats. The difference between a closed-throat breath-hold and an open-throat breath-hold is small--the difference between making a "k" sound and an "h" sound--but it's critical. To make the difference clear and to prevent you from inadvertently closing your throat, just keep trying to inhale slightly during the pause after you've taken a fairly full breath. Your goal isn't to take in more air, but to hold your throat open.

Since holding your breath is only dangerous if you ascend, practice it under conditions where you can easily control your depth--while holding an ascent line, for example. And if you think you may become confused between the "good" breath-hold and the "bad" one, don't try it.

RULE #4: Use Your BC Less

It sounds counterintuitive to say that you can control your buoyancy better by using your buoyancy control device less often, but that's how it works. For example, suppose you're a bit negative and slowly drifting deeper, so you squirt a little air into your BC. Suppose further that, by chance, that one squirt was exactly the right amount of air to make you neutral. But you don't stop descending immediately because you've got downward momentum. Your body and dive gear, though nearly weightless, have a lot of mass and take time to slow and stop, just as an ocean liner coasts forward long after its engines stop.

Your descent is gradually slowing, but you don't realize it so you assume you're still negative and squirt a little more air into your BC. Now you're actually a little positive, but that's not obvious either, because after you come to a stop you will seem to pause there for a moment or two. "Ah, I'm neutral," you think, but in fact the small amount of lift in the second squirt of air is gathering its strength, so to speak, and gradually beginning your ascent.

When you notice you're now moving upward, you dump a little air, making you neutral. But nothing happens immediately so you dump more air, and now you're negative again. And so on. This is why many divers seem to be constantly fiddling with their BC controls and bobbing up and down in the water column. What's needed is the patience to wait three or four seconds to see what happens after that first squirt of air before you hit the button again.

Naturally, you need to use some judgment. If you're dropping like a rock, you need to be more aggressive with your BC controls. Overweighting and a thick wetsuit or a dry suit complicate the situation too, because they expand or contract with depth changes and exaggerate your buoyancy changes. But, as you zero in on neutral buoyancy, you want to wait longer and longer before pushing those buttons.

Once you've found neutral buoyancy, you don't want to mess it up by touching the buttons again. You can make small buoyancy changes, to hop over a barrel sponge, for instance, by inhaling and holding it (with your chest, not by closing your throat). Likewise, you can get temporarily negative by exhaling as much as you can and holding that for a few seconds. You can make depth changes of four or five feet by using your lungs alone, without messing with your BC and losing that hard-to-find neutral buoyancy.

RULE #5: Drop Two Pounds

Don't worry too much whether the water comes to your chin or your eyes when you float on the surface. The weight calculation methods involving your height, weight, shoe size, whatever, just get you into a very big ballpark--within, say, four to six pounds of the right amount of weight.

In-water buoyancy checks can be inaccurate too, especially when done off the dive resort dock at the beginning of your vacation. During your first hours in the water, you're still keyed up and moving your arms and legs a little, which creates lift. The result is almost always too much weight, because when you can't get under the surface, it seems obvious you're too light, so you add lead. The real problem is getting rid of lead until you're within a pound or two of the minimum. And the only sensible, realistic way to do that is to experiment where it matters, at the end-of-dive safety stop with a nearly empty, buoyant tank. Here's the drill:

Step One: After finding that ballpark weight and checking it off the dock, take two pounds off your belt and put it in your BC pocket where you can get at it under water. So far, you're still carrying the same amount of weight. Now go diving.

Step Two: At the safety stop near the end of your dive, when you're down to 500 psi or so, hand the loose weights to your buddy. That's not too much extra weight for him to manage, or too much for you to lose--especially if you can grab an ascent line.

Step Three: Work on getting air out of your BC until you are neutral again. Roll on your back, for example, to move any air bubbles inside to your exhaust valve so they can be expelled. You should be relaxed now and not generating lift by finning unconsciously, but to be sure, grab your fin tips in the "Buddha" position. Can you hang neutral? Then you didn't need those two pounds and can leave them behind on the next dive.

Step Four: Before your next dive, return to step one and try to get rid of another two pounds. Keep it up until you can stay perfectly neutral at the safety stop with about 500 psi

RULE #6: Buy Less Gear

We can almost see dive retailers and manufacturers across the land lighting their torches and grabbing their pitchforks, but wait a minute, guys. We happen to be in favor of divers owning their gear, not renting it, because owners know their gear better and take care of it better.

We think they should buy the best gear they can afford, because there's no such thing as too much performance. We also think divers should buy their gear new, from a bricks-and-mortar dive store that wants their repeat business, not from a stranger with a web page.

That said, there are dangers to maxing out the plastic on a whole new kit of gear before the next dive. One is the danger of task overload. The demands of learning a new BC plus a new dive computer plus a new underwater camera may be overwhelming.

The better approach is to add only one piece of attention-demanding gear at a time. Delay diving with the new camera until the new BC is intuitive, until you can find the inflate/deflate buttons without conscious thought and can devote all your attention to the camera.

Another risk is the temptation to seek security in equipment rather than in technique. Anxious divers sometimes carry so many accessories to meet so many contingencies that they embark on shallow warm-water dives rigged for a North Sea wreck penetration. That risks task overloading again. A better fix is for the anxious diver to address directly the source of his fears, which is usually inexperience. The most experienced divers, dive guides and divemasters, for example, seem minimally equipped because they've learned to carry only the gear appropriate to the dive. As a general rule, get more experience before more gear.

RULE #7: Get Lost

When we ask divers what skills they feel most in need of improving, one of the top three is always underwater navigation. We're land creatures and disorientation is natural when the ground under your feet is gone.

Lack of navigational ability is often an unintended consequence of the structured resort diving that so many of us do. Following the dive guide, staying with the group and taking no responsibility for where you're going does nothing to develop your navigational skills. So leave the dive guide, leave the group and practice finding your own way.

One of the first things you'll notice is an unmistakable directional cue. It's a "natural" compass needle more constant than a magnetic compass and easier to read. It's the trend of the bottom, from shallow to deep. Since dive sites are usually located along a shoreline, "shallower" is the direction toward shore and "deeper" is the direction toward the sea. So if you leave the dive boat with shallower water on your left, you can find it again by returning with shallower water on your right. Putting the wall to the left when going and to the right when returning is the extreme case, but even the flat area on top of the wall has a shallow-to-deep trend, very noticeable if you look for it.

You can estimate distance by counting fin strokes or minutes, but cylinder pressure is probably easier because you check that frequently anyway. Assuming a constant depth, you could swim out for 1,200 psi. The return should take 1,200, leaving 600 for reserve.

You can use the depth to navigate a loop route as well as an out-and-back. Note the depth of the mooring or anchor before you leave it. If it's 30 feet, it will still be 30 feet when you return. You can drop down to 50 feet and swim along the bottom for about half your bottom time, then ascend to 30 and follow the bottom back to the mooring. Other orientation cues are the direction of the sun, the ripples in a sandy bottom (usually they're parallel to the shoreline) and the current.

As you strike out into the unknown, divide your route into legs, each no longer than you can see through the water, and pick out a memorable landmark at each end. At the same time, pay attention to the big picture. Try to visualize a bird's-eye view of the dive site with you moving across it. Sketching the site on your slate may help, too.

By John Francis

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