Buoyancy control lies at the very core of scuba diving. It’s the key to a safe and relaxed dive, and it affects many other important factors such as trim and air consumption. So it is for good reason that buoyancy control is one of the four essential skills of scuba diving! In the first part of the Scuba Fundamentals Series we discussed finning techniques. But however perfect your fin kicks may be, you’ll still be all over the place if you can’t control your buoyancy. So today we’ll discuss how to improve your buoyancy control!
Although buoyancy is taught early on in the Open Water Course, it can still be a bit messy for new divers – and that’s completely normal. Buoyancy control is a skill that you can (and should) always keep perfecting – even as an experienced diver!
What is buoyancy?
Buoyancy is the tendency of a body to float, sink or rise when submerged in a fluid. I will not go into the exact definition and all the factors that affect buoyancy now, but if you’re interested you can read more here. In scuba diving, you can adjust your buoyancy by adding/removing air (to either your BCD or lungs) or adding/removing weight.
When it comes to scuba diving and buoyancy, the goal is to be neutrally buoyant 99% of the time. This means that you neither sink or float; you simply hover in the same position. If you float up, you’re positively buoyant. When you go down, you’re negatively buoyant.
The importance of buoyancy control
If you ask me, buoyancy control is the number one most important scuba diving skill. There are a number of reasons why buoyancy control is so important, but safety is the main concern. If you can’t control your buoyancy, it’s impossible to be a safe diver.
There are three scenarios in which a lack of buoyancy control may lead to a dangerous situation: going too deep, going too shallow, or going up to fast.
Going too deep
Going too deep when scuba diving can have serious consequences. You risk going beyond your personal limits, which could lead to gas narcosis. Gas narcosis in itself is not harmful, but often leads to impaired judgement – and underwater that can have dangerous or even fatal consequences. Gas narcosis often also intensifies your state of mind, so if you feel uncomfortable or a bit stressed about your dive (which is likely to be the case if you’re not in control of your buoyancy) it could even lead to a panic attack. That’s never very pleasant in any circumstance, but it certainly isn’t when you find yourself underwater.
Finally, going too deep may even lead to going into decompression, which is something you should always avoid if you haven’t had proper training. Even if you follow your dive computer’s instructions, you’re putting yourself at risk. Recreational dive computers are not made for a ‘real’ decompression schedule. It will simply add time to your safety stop, and that may not be adequate, depending on how deep you went.
Going too shallow
Going shallower than you intended may not sound that bad, but can in fact lead to accidents quite easily. Whenever you’re in an area with a lot of boat traffic, it’s best to always stay at least 5 meters deep, until you’re certain that it’s safe to go up. But if you don’t have your buoyancy under control, you can easily find yourself floating up uncontrollably. The closer you get to the surface, the faster this process happens, and the bigger the chance of a boat running you over.
Going up too fast
But even in an area without many boats, going up too fast can still have serious consequences: decompression sickness and lung overexpansion injuries. I will not go into the exact definitions and risks of these injuries here, but if you’re interested you can find more information here.
Decompression sickness is something very complex that until today scientists don’t fully comprehend, but I’ll try to give you a very short and simplified explanation. Breathing air at depth means you inhale increased amounts of nitrogen that dissolves in your body. That in itself is not harmful, but it needs to exit the body at some point or another, which happens automatically as you ascend. But by going up too fast, your body doesn’t get enough time to get rid of all this excess nitrogen. This leads to the formation of bubbles, which may lead to decompression sickness.
A lung overexpansion injury may occur because air expands as you ascend. If let’s say, you hold your breath while going up, this can cause a lung rupture or worse; an arterial air embolism.
I can’t stress enough that these are all risks that should not be taken lightly. These three safety concerns are the main reason why it’s so important to improve your buoyancy control!
PRESERVE MARINE LIFE
Maybe you don’t care that much about your own life (in which case we need to talk), but you do want to preserve marine life. Having no control of your buoyancy inevitably leads to bumping into things. And in the ocean, bumping into things means destroying habitats or disturbing marine life. This is especially important for photographers and videographers, who need to get up close to their subjects. Unfortunately there are too many underwater photographers out there who only care about the perfect shot, and disregard the destruction they leave behind.
In part 1 of the Scuba Fundamentals Series we already discussed how proper finning techniques can improve your air consumption. The same goes for good buoyancy control!
When you adjust your buoyancy during a dive, you do so by adding or removing air. That can be either in your BCD or in your lungs. Either way, that air has to come from your tank. You can imagine that when your buoyancy is out of control, you have to make frequent adjustments. And the more adjustments you make, the more air you ‘waste’. Mind you, a certain level of buoyancy adjustment is always needed. It is completely normal (and necessary) to add some air to your bcd as you descend, and to release it again as you ascend. Safety always trumps air preservation, so please don’t hesitate to adjust your buoyancy because you want to save some air. But when you’re in total control of your buoyancy, you simply won’t need to make adjustments as frequently!
I hope that by now you agree with me that buoyancy is the most important scuba skill of all! In my opinion, buoyancy control can and should always be practiced and perfected, no matter your experience level.
You can now download my 6 favorite tips to improve your buoyancy control! These are the tips I give students who take a course with me, but because most of us are stuck at home for now, I’m making them accessible for free! Leave your email address below and I’ll send you the PDF.