Post by Dive Bunnie on Mar 30, 2009 8:27:17 GMT
So as we live in a fragile environment here, this is such an important skill for us. Although it should be an important skill wherever you dive. It is not good practice to pack on shed loads of lead, pull yourself down a shot line and not even think about adjusting your bcd or drysuit until you land crash bang wallop on the sand below. Firstly a nice controlled, slow descent ensures your ears have time to equalise, and also the visibility remains nice and clear so you can actually see something when you get there. And it just feels so much more comfortable to be in control of yourself while underwater.
So there are three things that affect your buoyancy in the water; adjusting the amount of air in your jacket (or suit), adjusting the amount of air in your lungs, and movement.
And it is a combination of all three that we can use whilst diving.
The BCD is an incredible invention, think of it as a hammock to carry you throughout your dive. As you descend, don't be afraid to add air little and often, to keep you almost neutrally buoyant. Just be aware that as you come back up again, this air will need to be dumped to prevent a runaway ascent. Be light fingered with both adding and dumping air, and remember that there is always a delayed reaction, so wait a few seconds each time you adjust your jacket or suit.
Our lungs are like two big air-filled sponges in our chest, so again can be used to fine tune your buoyancy throughout your dive. Don't rely on them alone however, otherwise you will end up breathing in an unnatural way which can be tiring, uncomfortable, and actually lead to using more air than you would normally expect. On a buoyancy check, fully exhale to check that you can actually drop down a metre or so. Before you descend, take a second to normalise your breathing if you have had a surface swim, or stressful entry. Then as you go under, exhale fully to help yourself get off the surface. Once down a metre or so, your suit will compress and help keep you down. If you find yourself a bit too close to something or someone underwater, breathe in fully, and you will rise up out of harm's way, breathe out again to return to depth without having to adjust your jacket at all. If you find yourself floating up a bit, stop finning and breathe out fully, to bring yourself back down to depth without having to dump air and then readjust your jacket as you descend back to depth.
Movement also creates lift. When doing a buoyancy check, make sure you remain still, otherwise you will find yourself adding lead that you don't need, because your movement will be preventing you from descending. Even a slight movement of your hands will have an effect. If you find yourself overtaking your guide, it means you are finning too much and using your movement for buoyancy. Add a little extra air to your jacket, so you don't need to fin much at all. If you get the urge to waft your hands whilst on a dive, again this means that you are feeling a little heavy in the water and just need to add a little more air to your jacket. If you find yourself drifting up above the others in your group, or your buddy, then stop finning, breathe out and you should return to your former depth. Make sure that you then lie horizontal so that you don't find yourself finning back towards the surface.
Hope this helps... happy diving ;D
So there are three things that affect your buoyancy in the water; adjusting the amount of air in your jacket (or suit), adjusting the amount of air in your lungs, and movement.
And it is a combination of all three that we can use whilst diving.
The BCD is an incredible invention, think of it as a hammock to carry you throughout your dive. As you descend, don't be afraid to add air little and often, to keep you almost neutrally buoyant. Just be aware that as you come back up again, this air will need to be dumped to prevent a runaway ascent. Be light fingered with both adding and dumping air, and remember that there is always a delayed reaction, so wait a few seconds each time you adjust your jacket or suit.
Our lungs are like two big air-filled sponges in our chest, so again can be used to fine tune your buoyancy throughout your dive. Don't rely on them alone however, otherwise you will end up breathing in an unnatural way which can be tiring, uncomfortable, and actually lead to using more air than you would normally expect. On a buoyancy check, fully exhale to check that you can actually drop down a metre or so. Before you descend, take a second to normalise your breathing if you have had a surface swim, or stressful entry. Then as you go under, exhale fully to help yourself get off the surface. Once down a metre or so, your suit will compress and help keep you down. If you find yourself a bit too close to something or someone underwater, breathe in fully, and you will rise up out of harm's way, breathe out again to return to depth without having to adjust your jacket at all. If you find yourself floating up a bit, stop finning and breathe out fully, to bring yourself back down to depth without having to dump air and then readjust your jacket as you descend back to depth.
Movement also creates lift. When doing a buoyancy check, make sure you remain still, otherwise you will find yourself adding lead that you don't need, because your movement will be preventing you from descending. Even a slight movement of your hands will have an effect. If you find yourself overtaking your guide, it means you are finning too much and using your movement for buoyancy. Add a little extra air to your jacket, so you don't need to fin much at all. If you get the urge to waft your hands whilst on a dive, again this means that you are feeling a little heavy in the water and just need to add a little more air to your jacket. If you find yourself drifting up above the others in your group, or your buddy, then stop finning, breathe out and you should return to your former depth. Make sure that you then lie horizontal so that you don't find yourself finning back towards the surface.
Hope this helps... happy diving ;D
