Excellent buoyancy control is important in cold water diving and photography. The different skill levels, physiological aspects of buoyancy and several techniques for greater buoyancy control are discussed.
Some of the most challenging and rewarding diving experiences are reserved for cold water divers. With the exception of Hawaii, Florida and parts of the Southeast, all of the United States offer cold water diving. While the temperature may vary from mid 70s(oF) to a just above freezing on an ice dive or deep wreck dive, there’s bound to be a fair amount of neoprene in evidence on every local dive.
Cold Water Buoyancy Control
Whether it’s hunting for lobsters, abalone or fish, or exploring reefs or shipwrecks, there is a tremendous number of cold water activities for divers. So, let’s begin our discussion of cold water buoyancy by defining just what “cold” is. That’s easy. Any dive that requires you to don a wetsuit fits the cold water category. How much neoprene you wear is dictated by actual water temperature and individual tolerance. The insulating properties of neoprene also make cold-water divers extremely buoyant compared to warm water divers. Consequently, they have to compensate by adding varying amounts of lead to their weightbelts.
Cold water buoyancy control, however, is much more than simply compensating for neoprene by adding a lot of lead. How much lead you wear, where you wear it and how you use your BC to compensate for it all have a direct bearing on your ability to enjoy a dive. Diving retailers and instructors around the country will be introducing workshops to help divers teach themselves the tips and techniques necessary for good cold water buoyancy control. Some will offer the workshops in a pool, while others will offer them in open water. The techniques are the same and divers of all experience levels will benefit from learning them.
The first point to emphasize in buoyancy control training of any type, warm or cold water, is that there are different levels of performance and skills that range from rudimentary to ultimate. For cold water diving, the following is the breakdown in skill levels:
Rudimentary: This is what you were taught in certification classes. You should not expect, during certification, to fully learn all the tips and techniques needed for sound buoyancy control. The classes teach you the rudiments and it’s up to you to improve them with practice and experience. This level of buoyancy skill is often characterized by gross overweighting (sometimes as much as 50 percent more lead than is needed) and a lot of air remaining in the BC at all times.
Basic: With a few open water dives under your belt, you will begin to relax and acquire basic buoyancy skills. You become more proficient in trimming air from your BC but still carry too much weight. When you stop kicking underwater, you sink, usually landing on the bottom on your knees and fins.
Intermediate: The ability to hold a position underwater, horizontally or vertically, without kicking, characterizes this skill level. BC trimming is second nature and the increments of air either added to or dumped from the BC are small. It’s impossible to reach the intermediate stage without paying attention to two important factors: the amount of weight you are wearing and where it is. Many divers, like skiers and other active sports participants, do get caught in a rut somewhere between basic and intermediate skills. The answer to improvement is practice and realizing you can easily increase your skills.
Advanced/ultimate: Even with thousands of dives, people still learn tricks to improve buoyancy control. At this level, a diver wears a minimal amount of weight, fully understands how tanks, weights and suits all contribute to buoyancy and can maintain any position underwater, even just inches off the bottom. It takes time to get to this level but it’s worth it.
In addition to these levels, you should also realize that buoyancy control skills get rusty without use. This is particularly important for cold water divers, whose diving often takes place on weekends or who may go several weeks (in the summer) or months (in the winter) without diving. It’s unrealistic to think your buoyancy control skills will be in any better shape than your wetsuit (I don’t know what happens to them in the closet) after a layoff!
What’s the answer? Use the techniques you learn here and in Buoyancy Control Workshops before you start any dive under the following conditions:
- When you buy a new wetsuit or are wearing an unfamiliar model, either a friend’s or rental.
- Whenever you change the amount of neoprene you usually wear. Additional vests, hoods, mitts, boots and farmer johns all cause significant changes in buoyancy.
- After a winter layoff or any significant period of time when you have not been diving fairly regularly. If the gear feels a little strange, take a couple of minutes and do a quick buoyancy control mini workshop.
- When using new gear. All BCs, even those from the same manufacturer, have different performance characteristics. So do tanks. There are big differences in the buoyancy of aluminum and steel tanks that may look the same. Diving with, and getting comfortable with, gear is probably the easiest way to achieve buoyancy control improvement, as well as increasing your confidence.
Buoyancy Control Workshops can be either formal or informal. While the formal ones (sponsored by stores and instructors) are extremely helpful in getting started, you can easily improvise your own version to fit any kind of diving conditions. Essentially, the workshops start with you wearing just mask, fins and snorkel along with your exposure suit. Jump in and don’t kick! On the surface or underwater, kicking is the biggest obstacle to improving your buoyancy control. Kicking makes you feel you’re in control when you’re not. It also makes you tired and causes you to gulp that tank of air down a lot faster than you need to. Crossing your arms and legs and relaxing will help you understand two important parts of cold water buoyancy control: individual differences in buoyancy control and the effect of neoprene on basic body orientation underwater.
Divers, even those of the same gender, height and weight, are not created equal. Understanding your basic body composition is a very important part in achieving advanced buoyancy control skills. The most important physiological facts include:
Body density: How much muscle (which sinks) versus how much fat (which floats). But how much you have or don’t have isn’t all that important. Fat is more buoyant than muscle but you need a lot of either to really make a difference in how much weight you wear. Far more important is:
Distribution of muscle/fat: This is where the muscle and fat are on your body. The obvious example here is women (who tend to carry fat low on their bodies) and men (who tend to carry muscle high and fat in the middle). By relaxing and not kicking, your body will naturally gravitate to your normal position. Get to know this position, since it’s better to know it and go with it than it is to fight it!
Lung volume: This is extremely important and often overlooked. The size of your lungs is important and their ratio to the size of the rest of your body is significant. So is the amount of air you are capable of inhaling and expiring with each breath. All of these contribute to buoyancy control.
The best way to start out is with no wetsuit to determine your body composition and how your body wants to position itself naturally underwater. Do this exercise in a pool, however, not in 60oF open water! Once you know your natural position, you can see how a wetsuit changes it. Almost all types of suits will change the way you float, since the distribution of neoprene over the body surface is not necessarily uniform.
By jumping in the water and not kicking you will get valuable feedback on what your wetsuit is doing, which is often slightly at odds with what your body would do without the wetsuit. Then it’s appropriate to add weights, but add them slowly, three or four pounds at first and then two at a time. Not only do you want to check whether you are positively or negatively buoyant, you also want to check what the position of the weights does to your orientation in the water. Individual physiology will dictate where to put them, but most divers prefer they be balanced (an equal amount on each hip) or evenly distributed around the waist. In either case, secure the weights in the position you want them with slides or stops.
Once you get the proper amount of weight on, you are ready to don your tank. Put it on but before you begin your dive, take a minute and relax on the surface. Anxiety and apprehension automatically cause the “fight or flight” reflex. In essence, our body prepares for an increased activity level by increasing respiration and preparing to use all possible lung volume. This translates into a significant amount of positive buoyancy so proper breathing becomes important. Then it’s down to a sandy bottom and there you practice horizontal and vertical hovering skills. Again, don’t kick. What you want to learn is just what effect all that neoprene, lead weight and individual physiology are having on your buoyancy.
Begin to pay real attention to how much air is in your lungs, which will become very obvious when you stop kicking. Your goal is to achieve a horizontal hovering position first and then a vertical one, all without kicking. Start paying attention to the amount of air in your BC as well. You want just enough to overcome wetsuit compression and no more. As you become skilled in maintaining the proper amount of air in the BC, you’ll notice breathing becomes the ultimate fine tuning weapon in developing intermediate and advanced buoyancy control skills. By moderating a relaxed rate of breathing, you can maintain that position – even a few inches off the bottom.
Last, some advanced tips on cold water buoyancy control. Some folks, as a result of physiology, will not be able to maintain horizontal or vertical positions without kicking. You are not a genetic mutant, you just have your weights in the wrong position. If, for example, your feet keep wanting to sink, you may be wearing your weights too low on your hips. If you reposition your weights and this still happens, try a lighter fin or add an ankle weight around the top of your tank. Check the position of your tank in the BC harness. The lower the tank, the faster you sink. If the opposite happens and you can’t seem to keep your feet down, they keep floating up, it could be your fins/boots are too buoyant or that your tank is too high. Often, however, it’s just (particularly with women) the distribution of muscle and fat. The best solution is to experiment with ankle weights to get the optimum distribution of lead weight.
As I mentioned, these simple exercises can be performed in a formal workshop or easily integrated into your normal diving activities. They don’t take long to complete, just 10 or 15 minutes, but they will reward you with more relaxed dives, increase your confidence and set you on the path to ultimate buoyancy control.
Cold Water Photo Buoyancy
While warm water coral reefs seem to be a focus for environmental activism, the ecosystems in cold water are often just as fragile. Kneeling on kelp and live areas of rocky reefs should be minimized; there’s no reason to have to land on the bottom except because you have the most rudimentary buoyancy control skills (or lack of them)! Nowhere is there a better test of intermediate and advanced buoyancy skills than with cold water underwater photography, a unique challenge in itself. Mastering the use of the camera system one handed is a must for beginning underwater photographers and care should be used in setting up your camera with this in mind. Your free (left) hand adds/eliminates air in your BC. It also masters the finger touch, where you steady yourself on the bottom with one gloved finger while taking a photograph.
With U/W photography, horizontal hovering and proper weight distribution become extremely important, as it’s your knees and fins that do the most damage in cold water diving. If you master horizontal hovering, this won’t be a problem, since your fins will be in the horizontal or even “up” position when you take the photo. To leave the scene after the shot all you need to do is take a couple of breaths. You will rise a foot or two off the bottom, then you can begin to kick. If you feel your developing buoyancy control skills are not up to this particular set of tasks, just choose a sandy area or a barren area and gently kneel to take your pictures. Since much of cold water photography is close-up or macro, both selective kneeling and the fingertip approach work well, environmentally and photographically!
The camera and strobe become significant parts of cold water buoyancy control. Although they are only about two pounds negative, that you often extend the camera (in normal and wide angle photography) in front of you exaggerates the negative buoyancy effect. When beginning underwater photography, experiment with different ways of holding the camera before you actually begin taking pictures. You will quickly grasp the changes in your buoyancy control and find it easy to build in proper compensation.
Handholding a strobe becomes quite a challenge and one reserved for divers with intermediate and advanced buoyancy control skills. Since both hands are holding camera and strobe, you have to drop the strobe in order to put air into or dump it from your BC. The best method to use here is to make sure your buoyancy is perfectly trimmed at the depth you will take the photograph and don’t change that depth much more than a couple of feet. If you feel yourself starting to rise, you’ll want to get the air out of the BC pretty rapidly. Just drop the strobe – you can easily retrieve it!
Cold water photography, other than close-up and macro, requires some pretty good buoyancy skills. Interacting with fish and mammals in cold water is exhilarating and challenging but requires a solid foundation and understanding of the key ingredients in cold water buoyancy control: body physiology and natural orientation, wetsuits, tanks, weightbelts and diver control of breathing. Join a dive store, dive boat, or instructor sponsored Buoyancy Control Workshop this summer. It may just be the start of a dramatic improvement in your diving skills.