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Sink or Swim: The Importance of Correct Weighting in Scuba Diving

Did you know that as humans, we are natural-born floaters? Yup, you heard that right! With our body fat and lung capacity, we are generally positively buoyant, meaning we can effortlessly float on the surface of the water by simply laying back and relaxing.

weight belts hanging on a rack

However, things get a little more complicated when it comes to scuba diving. Because of the increased buoyancy of exposure suits and BCD, divers need to add extra weights to their equipment to stay underwater. It's just one of the many fascinating things we learn during the OPEN WATER DIVER course!

How to determine the correct weighting in scuba diving?

The amount of weight needed for scuba diving varies depending on several factors, such as the type of exposure suit, construction of the buoyancy control device (BCD), the cylinder you are using, and any additional equipment like cameras, torches, reels, and so on. Plus, let's not forget about the quirks of our human physiology that can impact buoyancy!

Although some divers may wing it and take a wild guess at how much weight they need for a dive; based on irrelevant factors like how much weight their buddy is using or previous dives with different configurations, the safest and most comfortable way to find out is by doing a quick buoyancy check at the beginning and end of the dive. This easy step only takes a little bit of time and effort, but it can make all the difference in ensuring a safe and comfortable dive. So, don't leave it up to chance – check your buoyancy and dive with peace of mind!

Here's a quick and easy way to determine your correct weighting in scuba diving:

First, don all your gear and start with an estimated amount of weight. Next, with your regulator in your mouth, take a normal breath and hold it, then deflate your BCD. If you're perfectly weighted, you will float at eye level, and when you exhale, you will slowly descend.

But wait, there's a tip to keep in mind: stay still and avoid kicking during the check. Kicking can cause you to move upwards in the water and mess up your weight calculations.

If you're not quite there yet, simply add or remove weight as necessary until you float vertically at eye level on the surface.

And don't forget – after your dive, it's crucial to repeat these steps to account for any buoyancy shifts caused by changes in your cylinder's weight; especially for aluminium cylinders, which may be heavier when full at the beginning and lighter when near-empty at the end of the dive.

By following these steps, you'll be able to achieve perfect buoyancy and enjoy your dive to the fullest!

It's critical to adjust your equipment's buoyancy based on your weight at the end of your dive, especially since that's when you do your all-important safety stops. Ignoring this step can result in serious injuries that you definitely don't want to deal with. So, make sure to take this seriously and always prioritise your safety when scuba diving.

Why are new divers overweighted most of the time?

Listen up, newbie divers! When you're just starting out, breathing underwater might feel totally foreign, and your natural instinct is to hold your breath. But, when it comes to descending, you need to empty your lungs completely so you can descend safely without being overweight. It's not the easiest technique to master, but with time and patience, anyone can learn it!

Instructors often give their students more weight instead of teaching them the correct breathing and descent techniques. It's a real shame, because not only does this make diving more difficult than it needs to be, but it can also be downright hazardous.

And here's the thing - this approach is not only dangerous, but it leads to some seriously uncomfortable diving experiences. Overweighting causes bad body position, awkward swimming, and overexertion. You'll burn more energy just to move around in the water, and you'll use up more air without even realising why it happens.

It can take a long time to figure out what's going wrong if nobody's there to give you the right guidance.

So, don't let anyone take shortcuts regarding your scuba diving education. Make sure to learn the correct techniques for descending, even if it takes a bit of time and effort. If your instructor doesn’t take the time to teach you the necessary techniques, but simply adds more weight to your equipment, speak up about it or just look for another instructor to train with.

Overweighted divers are a common sight - divers that are just weighed down with more lead than they need, struggling to move through the water and looking like they are about to sink to the bottom.

It is due to a lack of understanding regarding the purpose of wearing weights, and it comes from both divers and – too many times – the dive professionals who train them. Some divers believe that adding extra weight ensures their safety by avoiding accidental ascents. But that's not how it works!

So, let's work together to change this. Educating ourselves and others about the importance of proper weighting and breathing techniques, we can avoid these problems and have safer, more enjoyable dives. Let's leave those heavy weights behind and start gliding through the water with ease and comfort!

What happens during a dive?

As we descend, the pressure causes our equipment to lose its positive buoyancy. The tiny bubbles in the material of our wetsuits will compress, and the weights we are wearing override the buoyant support of the equipment. To compensate, we add small amounts of air to our BCD to get neutral buoyancy. If we dive deeper, the air in our BCD compresses and provides less support, so we need to add air again. If we ascend, we need to let some of the expanding air out, or we become too positively buoyant and find it hard to stay underwater.

It is where overweighting becomes dangerous. Excessive weight causes a diver to add large amounts of air to their BCD. If they should ascend more than a couple of metres, the expanding air quickly overcomes the negative effect of the lead weight.

The issue escalates rapidly. Divers often try to swim back down while pressing the deflator button on the inflator hose. It has no effect whatsoever as the hose is downward, and the air travels upwards. In this body position, the air is in the base of the BCD - pointing to the surface - and unfortunately many divers don’t know where to find or how to use their quick dump valve, so the classic feet-first, uncontrolled buoyant ascent happens.

If this occurs after a long deep dive, the risk of decompression sickness or lung overexpansion injury increases dramatically. Not to mention what can happen if a boat passes overhead at that moment.

Are you ready to feel more comfortable and confident during your dives? Then it's time to dispel the myth that carrying extra weight is safer. In fact, it's the opposite! Wearing excess weight causes discomfort, rapid breathing, and faster air consumption, making it harder for you to maintain buoyancy and control your breathing. Worst of all, it's a serious hazard that can put your safety at risk. There is no good reason to be overweight with lead when you are diving.

But don't worry! There's a solution to this problem. By learning proper descending techniques and practising your breathing, you can achieve perfect buoyancy control underwater. And your instructor should be there to guide you every step of the way, teaching you these essential skills from the very first day of your diver training. So don't let excess weight weigh you down - take control of your dive and enjoy a safe and comfortable experience every time.

Whether you're a novice diver struggling with your weighting and breathing or a certified diver looking to perfect your skills, our FUNDAMENTALS WORKSHOP is just what you need! Book a personalised session with us to get the individual attention you deserve and take your diving experience to the next level.



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