Buoyancy control is a key element of diving safety. The physics concepts which underpin ‘floating’ and ‘sinking’ are simple. However, putting it all into action when immersed in water and fully outfitted with diving equipment may be a different matter altogether.
Every small change in equipment has an impact on buoyancy e.g. a change in the amount of weight being used, level of comfort by the diver in equipment especially BCD can dramatically effect buoyancy.
Divers with proper buoyancy control can maintain their position with very little effort. They can descend or ascend at will. In contrast however, divers with poor buoyancy-control skills struggle throughout the dive. In extreme situations, major buoyancy-control issues may cause divers to make grave errors such as descending well beyond their planned depth, negatively affecting gas consumption and no-decompression calculations, or on the flip side, uncontrolled ascents, increasing the risk of decompression illness.
Good buoyancy of course starts with proper weighting. It is essential that the amount of weight a diver uses allows one to descend, not causes one to do so.
Weight placement makes a difference, too. A classic buoyancy-control device (BCD) is generally configured to require a separate weight belt, whereas newer BCDs often integrate the weights. Each approach affects a diver's body position in the water, requiring time and attention to get comfortable. Using rental gear can complicate the process, especially for new divers, as each change in configuration, responsiveness and other variables can alter a diver's comfort and buoyancy. Diving with a drysuit, a weight harness or a rebreather adds to the complexity.
The BCD is the most complex piece of scuba equipment a diver must master which in turn will allow him to master buoyancy control, a diver must understand his BCD inside and out, including knowing how it reacts to the addition or venting of air. It requires proper maintenance to prevent sticking buttons or leaking bladders. Malfunctioning BCDs can lead to uncontrolled ascents or descents before a diver even realizes what's happening. Like any piece of equipment, proper function requires proper maintenance.
Seasoned divers will always advocate owning one’s own equipment for the reasons already mentioned above: knowing the equipment intimately; achieving mastery of it.
And if I could only own one additional piece of equipment beyond my own mask, what I would choose is to own my BCD.
What types of BCDs are available?
BCD's come in two main styles, jackets or wings.
Most divers learn to dive using a jacket style BCD - these inflate all around the body and around the waist allowing the diver to feel secure in the water, while also sitting in a nice position on the surface.
Wing BCDs only inflate behind you in a donut or horseshoe shape between you and your cylinder. Wings are preferred by more experienced divers because they hold you in a horizontal position in the water and do not obstruct your movements when fully inflated.
Wings are lighter and usually have greater adjustment in the straps with a simpler harness style strap system. Jackets have pockets built in either side of them for storage which makes them heavier for travel.
Recommended Jacket BCD
Oceanic Hera Women's BC/BCD Jacket Style BCD
Recommended Wing BCD:
Oceanic Excursion BC/BCD QLR4 Rear Inflation Bladder BCD
BCDs for ladies
Modern ladies BCDs offer female divers increased comfort and a much better fit compared to the unisex alternatives. Key features are that the back length is reduced, which means the cylinder does not rest on the base of the spine and the shape of the BCD is made to fit the female figure.
Integrated weights save the hips from the bruising sometimes suffered by using a conventional weight belt. Also, often the chest straps are removed on a ladies BCD to avoid constriction across the bust.
Recommended Ladies BCD:
Mares Kaila SLS Women's BCD Weight Integrated Scuba Diving BCD
Travel BCDs are designed to minimise weight and bulk to make travelling with them easier.
They tend to be made of lower denier materials with only basic features and are most suitable for tropical locations. Thinner material makes them lighter but also more fragile, they can cope with plenty of dives but too much rough and tumble around sharp rocks or wrecks can puncture the bladder so they’re best for open water diving.
Often steel D-rings will be replaced by plastic or aluminium ones which are strong but much lighter to help reduce the weight of the BCD.
Recommended Travel BCDs:
Cressi Sub Mens Travelight Ultra Light Scuba Diving Travel BCD
Cressi Sub Womens Travelight Ultra Light Scuba Diving Travel BCD
We have a whole selection of BCDs here available for you. Determining which is the best BCD for you depends on where you’re going to use it, along with your diving style and skill level. Lots of different choices for so many different divers and so many different diving styles. Pick the model that’s best for you and giant-stride into adventure.