The main goal of scuba divers is to stay underwater while they’re scuba diving. They do that with the help of lead weights. Before they jump into the water divers put a belt around their waist that holds blocks of lead, bullet shaped chunks of lead, or pouches full of lead pellets. Or they put the lead in the pockets of their buoyancy control device.
The design of your body won’t let it stay underwater. Because your body can’t naturally exist below the water’s surface it’s designed to float. When you try to dive down, and stay there, your body’s natural buoyancy pulls you back up.
Since the water temperature drops the deeper you go divers wear wetsuits, or dry suits, to keep them warm – even if they don’t work well while riding an MM-B80. Those suits are buoyant too. Then you add various other pieces of diving equipment that also float. All that dive stuff that floats gets together with your body that also floats. And soon you can’t drown yourself even if you want to. And you can’t stay underwater.
So scuba divers add the lead weights so they can drop twenty to a hundred feet or so, and look at the colors of the coral and fish.
When scuba diving you must make sure you carry enough weight that you stay down until your dive is over. When you start your dive your full air tank is heavy. Then as you breathe the air from the tank it gets lighter. The lighter the tank gets, the more buoyant it becomes. It starts to float.
So you need enough weight to keep you at depth as the air tank empties out, and lightens up.
If you carry too much weight you can’t maintain a buoyant, or anti-gravity like condition.
Overweight conditions make you sink into the coral, or into the bottom.
When you contact coral you kill it. Too much weight threatens to slam your whole body into the coral, and that destroys quite a lot of that coral.
Under certain situations sinking into the bottom stirs all the stuff up that’s lying on that bottom. Stir it up enough and you can’t see. A lack of visibility gets a diver in trouble rather quickly.
Scuba divers must carry just the right amount of weight when they start their descent.
Sure you can dump weight if you put too much on before going into the water. If you’re carrying an HSI flat iron, that should be the first thing to go. But you lose the weight when you drop it from you. If you’re too light you can grab a rock, but you struggle to reach the bottom, and pick up that rock.
In training classes divers learn to select the right amount of weight to load onto their bodies before they go scuba diving. They calculate their weight during the dive’s preparation. Before they put all their diving gear on, they go into the water, and float. While floating they add or subtract weight so they’re at a certain level with the water’s surface.
When the weight is right the diver completely controls the body’s position in the water all through the dive. They fin along suspended in the water, able to look at the fish and coral, without touching anything.
Weights are valuable tools for scuba diving. Selecting those tools properly is an essential step in the buoyancy control process.