Buoyancy Compensators

By Doug Pemberton

There is no piece of diving equipment that has undergone a more dramatic evolution than the buoyancy compensator. The simple bag of air of not too long ago has evolved into an essential piece of equipment designed for safety, comfort, and convenience.

Just in the past twenty years the small selection of compensators hasincreased dramatically to provide a variety of styles to fit nearly every diver and diving need. Buoyancy compensators have evolved from the Mae West design of the early 70s to the horse collar (or toilet seat) design of the later 70s and the buoyancy jackets of the 80s. As we enter the next millennium we have a variety of very sophisticated devices designed for a variety of functions and body shapes. There are BCs for warm water diving, cold water diving, technical diving and modular BCs that can be fitted with a variety of bladders and fittings allowing for multiple usage. There are also BCs specifically designed for women, with special padding and panels of non-constricting materials.

BCs may be designed for a variety of uses, but their primary function is to compensate for negative buoyancy. The two predominant styles on the market today are the jacket style BC and the back inflation design. Jacket style BCs have the air bladders around the sides and front of the user. They are very comfortable and for most divers they work very well. But technical diving has had a profound influence on recreational diving in the past few years and for the technical diver who may wear tanks side-mounted (hanging from the BC), the jacket style would not work. The answer was to move the air cell to the back of the BC where it is completely out of the way. This design has now become quite popular in recreational diving. In many cases back mounted bladders can be easily removed and exchanged for smaller or larger bladders making them adaptable to a variety of situations and needs.

Speaking of technical BCs, they vary considerably from the recreational units. Although they can be used for recreational diving they are designed for the serious techie who needs the various and specific features of the BC, such as stainless steel back plates, half a dozen or more stainless steel D-rings, optional dual bladders and specialized pockets.

BCs are made from a variety of nylon materials such as 420, 840 or 1000 Denier nylon and even ballistic nylon and Kevlar. The various numbers refer to the weight of the nylon used in production, the higher the number, the tougher the fabric.

One of the big recent advances in buoyancy compensators is weight integration. Anyone who has had to walk more than a small distance when wearing a weight belt knows how uncomfortable it can be on the hips and lower back. Recently many manufacturers have designed BCs, both jacket styles and back inflation units, that can be loaded with up to 40 lbs of weight. This makes things much more comfortable for the user, but don't expect any Christmas cards from some charter boat operators who may occasionally have to lift the unit out of the water.

Another important feature of any BC is the inflator unit. These have varied over the years in shape and design in order to make them more ergonomic or streamlined but they all work well. A few manufacturers also offer units that have a regulator built into the inflator unit and act as emergency octopus regulators while still allowing you to inflate the BC.

All compensators work well but the trick is to find the one that is going to fit your particular needs. More may not always be better but it is also a good idea to buy with an eye towards your future diving needs. Manufacturers have many styles of buoyancy compensators to choose from and several options that can be integrated at a later date.

Technological advancements in materials, designs and accessories have all helped to make the lowly bag of air an essential piece of diving equipment.

LEFT: ZEAGLE RANGER - Modular BC for the serious recreational diver with an eye towards technical applications. A variety of bladders and pockets and other accessories are offered .
RIGHT: MARES FRONTIER VERA - Specifically designed for the female diver.

CRESSI-SUB AIRLIFE - Jacket style BC with large weight integration pockets and adjustable lumbar support.

GENESIS ATHENA - Back inflation, weight integrated BC designed and tailored for women.

OCEANIC CHUTE 2 - A serious recreational BC with technical features. Back mounted air cell with optional weight integration.

OMS IQ PACK - Harness only. Allows the attachment of several styles of bladders for a variety of needs with single or double tanks.