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DIVE PLANNING - It Separates the Pros from the Amateurs

Buoyancy Control - The Keystone of Good Diving

I have long taught my students that there are two things that separate good divers from the pack. That is buoyancy control and dive planning. And there is more to both of them than you think. Read on and then gather up your gear and go out and practice because if the last time you practiced buoyancy control was during your basic course, I can assure you that your buoyancy control leaves a lot to be desired.

Three Buoyancy Compensators (BC's) to better buoyancy control.

That's right, three bcs. First of all, there is your buoyancy compensator, which is what most people think about when we talk buoyancy. But there are two other bcs, Breath Control and Body Control. Let's take them in that order.

Your Buoyancy Compensator

The buoyancy compensator is used for gross changes in buoyancy. These changes take place due to wet suit compression, compression of air in our bc, and changes in the weight of our tank as we use up our air. There are a few things that are important to remember about our bc. First of all it is not an elevator,! We do not use our bc to bring us to the surface and allow us to sink. We use our bc to maintain neutral buoyancy at all times. This is a very important concept. Let's look at the proper use of a bc during a dive.

You add a little air to your bc prior to entering the water. This assures that after hitting the water, you return to the surface immediately. This allows you to make sure your mask strap is still in place, your weight belt is not sliding down, and you are with your buddy. It also allows you to signal the boat crew that you are ok. (Admittedly, some very experienced divers enter the water with no air in their bc and commence their descent immediately. But these are very experienced divers.) To start your descent, you should let all the air out of your bc and then using either a line or a surface dive, begin your dive. I prefer to swim downward on a slight angle, clearing my ears as I go. Remember, if you are descending feet first, the greatest drag created is by your fins. This will usually cause you to lean backwards and you will find yourself descending butt first! At this point you are actually falling through the water. If you can not clear your ears, it is difficult to stop your descent immediately. If you are swimming down, all you need to do is level off to stop the descent. Now, as you continue your descent, you need to add air to your bc to maintain neutral buoyancy or at least be close to neutral. Do not wait until you reach the bottom to start adding air. If you do that, then you need to add a lot of air to get it right. If you make big changes, then you can make big mistakes. Make small changes and you will only make small errors that are easier to correct.

Throughout your dive you will need to make changes as you change depths or as your tank gets lighter due to air consumption.

At the end of the dive, as you start your ascent, you must start letting some air out of your bc in order to maintain neutral buoyancy during the ascent. If you do not, the air in your bc will start to expand, your wetsuit will start to recover from its compression, and you will start to be carried to the surface by your buoyancy. This is not buoyancy control. If all of a sudden a boat motor starts or a boat starts to approach the area, you can not stop your ascent easily. If you were neutrally buoyant, you would stop where you stopped kicking. That is a controlled ascent.

It is also important that you know your bc. If you want to learn more about bcs, look at our equipment section for the piece I wrote on bcs.

The bottom line is: you let all your air out to start your descent, then you add air as your descent continues. As you ascend you let air out until you reach the surface, then you add air to keep you afloat at the surface. Got that?

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Your Body Control

Our second "BC" is body control. Understand that your body wants to go in the direction that the top of your head is pointed. If your point your head up, your body goes up, if you point your head down, your body goes down. That said, let's explore body control.

Newton's Second Law states that "For every reaction, there is a direct and opposite reaction." First of all note that Newton said for "every" action. That means if you are at the surface and have let the air out of your bc and you expect to sink, that the best way to do that is not feet first. That is because every move you make tends to push you back to the surface. If you just move your legs to balance yourself, that action has an opposite reaction (pushing you up). If you move your hands through the water, there is an opposite reaction to that action. Your best bet is to do a surface dive and then the movement of your fins pushes you downward.

Remember as a kid, holding your hand out the car window to ride the air waves". Tilt your hand up and it goes up, tilt your hand down and it goes down. Your body acts like that in the water. If your are swimming along and you tilt your head up, your body goes up. Therefore your body must be parallel to a depth if you expect to remain at that depth. The problem comes in the way we where our equipment. If we are wearing our weight belt around our waist, it is really in the wrong place. We should be wearing it around the center of buoyancy. For most of us that is probably 8 - 10 inches above our waist. Of course, it is not practical to wear a weight belt there so we wear it lower. But that pulls our legs down, which means our head is pointed upward and we go up. How do we deal with that? We add more weight! And our legs sink even more. We made the problem worse. This circle continues until we have add so much weight that no matter where our head is pointed, we are not going up! And now when we get to the bottom we need to add that much more air to our bc to compensate for this excess weight. Of course, that air goes around the top half of our body and compounds the problem. Our body control is not under control. At this point we are now pushing our body through the water on an angle and not in a streamlined head-first position and we are pushing our bc through the water half full of air. Try pushing an empty bc through the water and try pushing a bc full of air through the water and see the difference. So the amount of weight that you use corresponds to your body position as you push it through the water.

Notice the way a shark swims as it moves through the water. It is propelled by its tail (as we are propelled by our fins). When he wants to turn, he draws in a pectoral inward tilting his body in the direction of the turn. He then arches his back and glides through the turn. You can do the same thing. You want to turn? Drop one shoulder, arch your back, continue to kick and watch your body go through the turn. Your hands never leave your side. It is like flying. Practice it and you will be amazed at how effortless it is.

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Your Breath Control

We all know that every time we inhale we go up and every time we exhale we go down. So it must have some effect on our buoyancy. It definitely does. We can use that effect to our advantage.

When someone realizes that they are too buoyant, the first thing they do is reach for their inflator hose and bring it up above their head to dump air. Two other things happen at the same time. By going into a head-up position, they proceed to move even shallower and, secondly, they are now pointed in a position to move them even shallower yet. What they should have done is quickly exhale and held that breath out. Yes, I did say hold your breath, but I said hold it "out." By exhaling you quickly get rid of several pounds of buoyancy. That buys you little time to get a hold of you inflator hose and dump some air. Remember, you don't need to dump it all, just a little. You should just be a little off. Also, make sure that you use the rapid exhaust at the top of your inflator hose or the dump on the back of your bc to do this. If you are not sure how these work, talk to one of our staff and they will demonstrate it for you.

So, you can see that you can use breath control to your advantage.

The bottom line is that proper buoyancy control takes all three of these methods. And proper buoyancy control is not something that just happens. If you think that someday it will just come to you, look in your Day-timer. Someday is not there. But if you practice these techniques, take an advanced course, think about how your movements and prescence in the water translates, and you work on buoyancy for the next 25 dives that you do, you will never have to think about it again. And you will be part of that group of divers that every one admires because you make it look so easy. Go for it.

Dive Planning - It Separates the Pros and the Amateurs

I have long said that there are two areas where most divers don't pay enough attention -- Buoyancy control (see above) and dive planning. Most people look will tell you that they do plan their dive, but as you can see below, there is a lot more to it. You first started dive planning when you decided to get certified and made the calls to find out what steps were necessary to achieve that goal. In doing so you had made a critical evaluation - that you did not have the skills and the knowledge to be a diver. You made plans to change that. You need to continue to make that evaluation over and over again as your diving career progresses. You also need to make a few other evaluations relating to your physical condition and your equipment and your choice of dive locations.

You -- Your Knowledge and Your Physical Condition
This is the tough one. Look in the mirror - you handsome devil (or devilette). You want to think that you are in as good as shape as ever and can still do all the things you used to do. I always say "I can still do all the things that I used to do, but it hurts a lot more (and a lot longer.)" The truth is that most of us are not in the same shape as we were a few years ago. (I know there are a few exceptions and I don't really hate you.) Age and job stress do take a toll, sometimes subtly. You need to be hard in your evaluation of your physical condition. Is it time to get to the gym or back on the bicycle? Do you need to lose 10 pounds (if just to get back into your wetsuit)? Are you still smoking (you know it is killing you.)? What are you going to do to change these things. If nothing, then maybe you need to change the type of dives you are exposing yourself to. Unfortunately in diving today there are a number of fatalities caused by heart failure. In a sport only 50 years old, we are seeing a population that is aging. That needs to be considered in our evaluation of ourselves.
The other side of looking at ourselves is "What are our skills like?" Is this the year that we take the Advanced course, or the Rescue course, or maybe Nitrox or Equipment Specialist? Are you planning on becoming a Scuba Instructor someday and want to get moving on that path. If there is something you plan on doing "someday", look in your day planner. You will notice "someday" is not in there. Maybe there will be one in your next life. Or just maybe you should sign up for that class NOW. Make a plan.
Now that you understand this part, let me say that you need to do it every year. I tell my students to look at it at the beginning of the year, make these evaluations and get it on their calender. You can click here to look at our course schedules and descriptions. Find out when the course is given and block off those dates.

Your Equipment
If you are a certified diver, you have probably have already figured out that diving is an equipment-intensive sport. Having the proper equipment (properly maintained) is very important. Remember that this is life support equipment. Again, from the perspective of the beginning of the year, we need to make some evaluations about our equipment and make some plans relating to it. First of all, do we have our own equipment. If you do not it will be hard to ever become a really good diver. If you tried to play tennis with a different tennis racket every time or golf with a different set of golf clubs each time, you would never get any good at it. Diving is the same. If you do not have your own equipment, read our piece on "How to Buy You Own Dive Equipment". If you do have your own equipment, you need to decide if it is still sufficient for the diving that you are planning on their boat. doing. Does it need to be replaced, serviced, or modified. We have several upgrade programs available. Give us a call. If your equipment needs to be serviced, you need to get it to us in January or February. If you wait until April, (like all those other people who do not do any dive planning), then we are swamped with equipment that needs to be overhauled. Get it to us early. Get in the habit of bring it in January and it will be due for it's next overhaul in January. Then we are not rushed trying to get it done in time for you. If you are planning on renting equipment, you don't need to do it in January, but you do need to do it in advance of when you will need it. In advance does NOT mean two days in advance. It means more like ten days in advance. You might get away with two days, but don't count on it. Sooner or later your luck will run out.

Where Are We Going?
Now that we know that we and our equipment are taken care of, we have to decide where we are going diving. Many people like to wait until the last minute to schedule their dives and trips. With the number of flight cutbacks since 9/11, you may find that you are unable to get on the flight you want or that the ticket price is considerably more. Neither of these are good options. Nor are either of these in our control. Sign up early. Again, you need to get these dates filled in on your schedule. You should look at the trips that you want to do, the boat dives you want to make, and the special days like Underwater World Day that you want to attend. Then you need to get these filled in on your calender. You see, if you don't fill in your calender, someone else will fill in those days for you. Instead of going diving with us, you will be going to a baby shower. That should get you motivated to follow these instructions. If you have a dive planned, it is easy to say, "Oh, I would like to, but I made previous arrangements." You can click here to check out our Travel or our Boat Dive schedules. It is also important to find out what special requirements are necessary for that dive. In the case of travel, is a passport required? Is yours current? Some places will not accept a passport that expires in the next six months. How current is yours? Diving locally? Outside the quarry you are normally required to have a dive flag. And some places, like Shark River Inlet, the Coast Guard prohibits diving before 5 pm (too much boat traffic) and nature prohibits diving anytime but slack tide. So advanced planning is important. Some dive boats require that you have a pony bottle to dive off their boat. Do you have one? Or at least have a rental reserved?

The Day Before
This is the time to perform some very important checks and it is very important that these checks be performed at the right time. If you go out after work on Friday night, come home at 11pm and find that your regulator is free-flowing, you are in trouble. We can be a lot of help at 6pm but at 11pm we are hard to find. So come home from work first and do the following: Put your regulator on you tank. Check the tank pressure (on both tanks). Just because your tank was full last week, does not mean it is full today. You may have a slow leaking neck o-ring or blow out disc. Your rotten nephew may have been over and played with the valve, leaving it slightly open. Or, just maybe, it was mistakenly not filled. We hate to think that those things happen but they do. Whatever, standing on the boat with a half of tank of air does not make for a good start to the day. Now go breath off the regulator. (Don't just push the purge button.) Inhale and exhale. Make sure that your computer turns on. Go through your check list and make sure that you have everything. Then put all your gear except your weights and your tanks into your dive bag. Put everything together so you can grab it in the morning. Do NOT put your weights behind the door or the sofa so you do not kick them when you stumble in late that night. If you do, that is where they will be tomorrow when you go to get geared up on the dive boat. Remember that when you are loading the car in the wee hours of the morning, you are probably still half asleep and it is easy to forget something.

The Dive - Finally
Well, not really. We still have some planning to do. The first item on your list when you arrive must be the site survey. Are the conditions safe for the planned dive? Is the surf too rough? Or the currents too strong? Or visibility too low? The best plan might be to abort the dive right there and then. Don't be afraid to do that. I have on several occasions. Then decide on the planned depth, time and general direction of the dive. Discuss what action will be taken if you are separated. Don't assume that you know what your buddy plans to do. Then choose a team leader. This is the diver who will lead the dive. The buddy will follow. This will greatly reduce the chance that you will become separated. What often happens is one buddy sees something and goes left while the other buddy sees something and goes right. Both are thinking that the other will follow. Ten seconds later you are separated. The leader leads!!! This is especially important in three person buddy teams. The problem here is that each buddy thinks the other buddy has the third buddy in sight. In truth, neither buddy has the third buddy in sight. A very dangerous situation. It is the responsibility of the team leader to be sure that both buddies are with him.

The Missing Link See, you have to read on to what the missing link is. Well, it is the one action that nobody takes in dive planning - the debriefing. If you don't talk about what happened you will see the same problems come back to haunt you again and again. Discuss those problems even if they are minor. it will prevent them from growing.

As you can see, the bottom line is that if you only spend a few minutes planning a dive, you are compromising the safety, fun and comaraderie of diving. So get your diving planning act together.