Proper Weighting Techniques for Optimal Scuba Diving Buoyancy
The benefits of being properly weighted while scuba diving are obvious: increased safety, improved air consumption, and even a better chance of seeing more wildlife because you won’t be bumping across the reef or silting up the environment. So, what is the perfect amount of weight for you to wear for optimal buoyancy while scuba diving? Well…it depends.
Think back to your open water class. You learned a general guideline for how to calculate the weight you needed that took into consideration the type of water you were diving in (fresh or salt), the thickness of your exposure suit, the type of tank you used, the weight of your gear, the buoyancy (or lack thereof) of your fins, and your body weight. From there, it was a matter of fine-tuning the amount by doing a weight check in the water.
Now that you are a certified diver, you should have a decent idea of what to wear for the various conditions you encounter. But we’re all creatures of habit and it’s easy to become complacent and use the same amount of weight regardless of conditions. Proficient divers can control their buoyancy even if they are poorly weighted, but it isn’t optimum. New divers that are poorly weighted often find themselves dragging across the reef, or are unable to control their ascents. Not only is that not optimum, but it can be dangerous as well.
So, let’s review.
An easy rule of thumb is to take about five percent of one’s body weight, add two pounds if wearing a wetsuit, add or subtract two pounds for the type of tank. That’s going to get you into the ballpark, weight-wise. PADI’s weight guidelines is more complex, but potentially more accurate.
But with all the variables here are a few things to remember:
Body weight is the biggest factor to consider when determining the amount of weight to use when diving—but not all body weight is created equal in the water. Muscle is more dense than fatty tissue. Women tend to be more buoyant than men.
Scuba tanks are usually aluminum or steel—and size matters. Steel tanks are heavy, and the bigger the tank, the less additional weight you’ll need to add to your kit. Some divers choose steels for exactly that reason. Aluminums, on the other hand, are lighter. And all tanks gain buoyancy as they empty, so it is better to start the dive a tad (emphasis on a little) over-weighted so by the end of the dive, you can comfortably complete a safety stop during your ascent.
Wetsuits. Basically, the thicker the neoprene, the more buoyant the suit. That said, there are wetsuit manufacturers who have increased the exposure rating without increasing the buoyancy of their materials. Neoprene also compresses—at depth and over time. A new suit tends to be more buoyant than an older suit. Diving in cold water? Adding a hooded vest, hood, gloves, thicker booties, or extra layers under the suit all add buoyancy.
Dry suits and rebreathers can also greatly affect buoyancy. The guidelines issued by the manufacturers will help you figure out how to properly weight yourself with their equipment.
Now it’s time for a weight check. Gear up, and as a safety precaution, add some air to your BCD in case you are over-weighted. Breathe through your regulator and enter water that is too deep to stand. Completely deflate your BCD. Hold a normal breath; if you float at eye level, congratulations! You are properly weighted. If not, adjust according in small increments. Once properly weighted, merely exhaling should be enough to slowly start your descent.
Still having a tough time? Jupiter Dive Center offers Peak Performance Buoyancy courses that will have your buoyancy optimized in no time. After all, mastering this fundamental of diving will increase your safety, protect the reef, improve your air consumption—and that all adds up to a better and more enjoyable dive!