Stay afloat by Doug Pemberton

Things used to be so simple. When I sat down to pen an article on buoyancy compensators I thought it would be pretty straightforward, after all, I'd be writing about little more than a bag of air. Come to think of it, there was a time when that is all a buoyancy compensator was. My first introduction to the BC was with a Mae West type vest, with a hole in the top to put your head through while the bottom was tied around your waist. A hard rubber inflation tube protruded from the vest. You took your reg out of your mouth, grabbed the top of the tube with your teeth, pulled up on it and blew in. Thinking back on it, things may have been simpler, but how we managed to survive some of that old equipment remains a mystery.

Over the years, experience, needs and technology have combined to transform that old bag of air into a very sophisticated piece of equipment. For the most part, dive gear does a good job at doing what it was designed for and most manufacturers offer a full range of gear to cover the needs of novices and well-seasoned divers. Choosing a BC, or any piece of dive gear for that matter, should be dictated primarily by your personal needs based on the type of diving being done. All are built for safety and comfort but a few are designed to meet the specific requirements of certain kinds of divers.

Two of the biggest features, becoming more popular in BC design, are weight integration and back mounted air bladders. Being able to load the weights into the BC removes the pressure of weight on the hips during those hikes to the dive site. In the water the weight acts to stop the inflated BC from floating up and becoming restricting or uncomfortable. The downside is that you might not be very popular with the charter boat skipper who lifts your gear out of the water for you after a dive. In all systems weight can be easily and quickly dumped when necessary.

There are three main categories of BC on the market. The recreational BC is intended mainly for use with a single tank although some can be adapted for use with doubles. The single air bladder may wrap around the sides of the lower torso or be back mounted. Pockets and lightweight D-rings are provided for convenient attachment for carrying of lights or goody bags. Some of these may offer optional weight integration.

Most BCs are made of various grades of durable fabrics such as 420 or 840 denier nylon. Some may even be made of 1040 denier nylon, sometimes referred to as ballistic nylon. Denier refers to the weave of the fabric. The higher the number, the tighter the weave and the tougher and more puncture-resistant it becomes.

The second category are the advanced recreational BCs which have been influenced by the recent emergence of technical diving. Most incorporate a back mounted bladder. Some may be of a modular design which allows you to remove, mix and match various parts of the BC such as the side panels, harness and even install different sized bladders. They will easily adapt to use with single or twin tanks and will sport several heavy duty stainless steel D-rings which can be used for the attachment of pony tanks, reels, lift bags and lights. Chest straps and optional crotch straps may be available for added stability. Many of the advanced recreational BCs are also weight integrated.

Finally, there is the technical diving BC. Technical divers need a BC that is compact, yet will allow them to carry a great deal of weight and equipment. It is not uncommon for "techies" to dive with twin 80 cu.ft. tanks, or larger, on their backs and two sidemounted tanks, plus a suit-inflation bottle, large battery packs for lights and an assortment of other necessary items. The true technical BC has a back mounted bladder and is of a modular design. Most offer bladders with a higher lift capacity, up to 100 lbs. Redundancy, or having two of everything, is a big aspect of technical diving and some units provide dual bladders. The physical size of the unit is also very important so most of the technical BCs have some method of constricting the bladder to keep it as compact as possible, especially when deflated. Up to a dozen or more stainless steel D-rings are provided for placement of sidemounts and other necessary gear. A cross-chest strap and crotch strap help to ensure stability and a snug fit. Pockets are usually purchased separately and attached where needed.