CHOOSING A BC
You may have read my blog explaining buoyancy control and why you need a BC. Actually, you need a BC for three distinct purposes. The first is to enable you to wear your tank on your back, or even side-slung as is a modern fashion with a few divers who want to emulate intrepid cave divers.
The second is to give you support or flotation at the surface. When inflated, you need it to float you comfortably in a vertical position. In fact, the earliest BCs were called Adjustable Buoyancy Life Jackets although with no permanent flotation this was something of a misnomer. The third reason is to allow you to use it for buoyancy control.
Ask on a diving forum what sort of BC you should buy and the inevitable answer will be "a wing-style BC with a stainless-steel backplate, because you're going to need it one day." They assume you are going to eventually become a technical diver.
It's true to say the majority of dives done world-wide are with single tanks so telling you to get something suitable for use with multiple tanks can be very misleading. People who get into multiple tank technical diving are very much in a minority and even they will be using inappropriate equipment if they use such a BC for an ordinary leisure dive while away on holiday.
A conventional jacket-style BC is far more appropriate for this. Why? Because such an item usually comes with one or more pockets for carrying ancillary kit such as a surface marker buoy or safety sausage and other items such as a reef hook or a small underwater lamp.
A lot of nonsense is often talked about attitude in the water, citing the idea that a wing-style BC will let you swim in a better horizontal position. The truth is that the air in either style of BC will always migrate to the highest place under water, which is directly behind you shoulders in both cases. The difference comes when you fully inflate the jacket-style BC because once the top of the buoyancy cell is inflated, the lower part that is positioned towards the front underwater also inflates and that should sit you upright in armchair comfort while you wait to be picked up by your dive boat.
So what's the point of a wing? A wing-style BC can have an enormous buoyancy cell that will be adequate to float you and several heavy steel tanks. At the same time it offers an uncluttered chest area so that a diver can hang all the regulators that go with those tanks, while the metal backplate offers more locations to stow kit.
Loads of potential lift must be a good thing, mustn't it? As a rule-of-thumb, you don't need more lift than you have weight on your belt. That is especially true when using aluminium tanks popular at leisure diving centres abroad. A big wing, fully inflated, with tend to thrust you face down at the surface if used with a single tank. It's not the right tool for the job. A BC with, say, only 10kg of maximum lift can be quite adequate for this purpose.
If you like the idea of the uncluttered chest area, you can get a leisure diving wing-style BC with a more appropriate size buoyancy cell. It's a question of personal choice.
When you come to pack your bag to travel, it will be apparent that the BC might be the heaviest item of diving equipment you have. A good solidly built BC might be very hard wearing and great for diving locally but at this time you'll wish you had a more lightweight one. The cost of an extra BC for foreign holiday use can soon be recovered in the savings on excess-baggage charges. Whether conventional in layout or a wing, there are now many lighter weight BCs available and some can even be rolled up to form a compact shape in your bag.
Get the right tool for the job. Don't be bullied into getting the wrong BC just because a disinterested party on the Internet has given you a bad steer. When you visit Mike's Dive Store, explain exactly what sort of diving you need it for and the staff there will help you to choose what's appropriate for your needs. It's in their interest to make sure you are happy because happy customers are regular customers. There's a large range of different solutions to the BC choosing problem and it's important that you end up buying the right one - and if you do take up cave diving or feel you want to side-mount your tank/s, they'll be ready with the right solution for that too!
My next blog will be about actually using your BC under water. It includes a particular hobby-horse of mine.
Happy diving - John Bantin
