Buoyancy Control Device (BCD)

The Buoyancy Control Device (BCD)

Buoyancy Compensator (BC)
- This makes buoyancy control easy. For more on buoyancy control and its importance
- Inflators: Can be orally or mechanically operated
  > For oral inflation, the manual control button is pressed to open the passage in the tube connected to the BC while the diver blows into the mouthpiece. > Mechanical inflation (low pressure inflator) involves the push of a button to inflate the BC with air from the cylinder
- Deflators: Are operated either by pressing the low pressure inflator or activating a dump valve which dumps air more quickly
  > Having a BC with a dump valve in multiple places is handy so you can use the valve in different positions
- Weight systems: Some Buoyancy Compensators have a weight system built into them which removes the need for a weight belt which can take the stress off the back (both a diver with the system and their buddy must become familiar with its efficient use)
- The BC you choose must have sufficient lift for your body weight, the amount of lift a BC will provide will be displayed on the item
- Other features of BC belts include adjustments, straps and pockets which may allow a diver to carry other equipment and remain more streamlined
Weighting: On the surface, some weight is required for negative buoyancy to allow descent
- This can be integrated into the BSC (see above in point 1)
- Belts used are:
  > Nylon, which is strong and can hold a lot of weight > Neoprene and nylon mesh belts which hold the weights in internal pockets, allow weights to be easily removed and added. They are more comfortable then the regular Nylon belts
- Buckles on belts must be easy to release with one hand and made of non-corrosive material
Weights
- Some are covered in vinyl to protect surfaces they come into contact with from scuffs and scratches
- Soft weights are soft pouches contained lead which many feel are more comfortable then other types

How much does the BCD cost/ to buy?

Starting: $350 Top Range: $800

Scuba Diving Equipment / Diving Gear

A Buoyancy Control Device (BCD), also called as buoyancy compensator, is a diving equipment generally worn by professional divers for life saving emergencies both on the surface and underwater. The BCD equipment also provides the ability to control and adjust the buoyancy level of a professional diver. This allowing him to have a neutral or stabilised buoyancy level underwater.

Early versions of the BCD equipment have specialised inflation cylinders. Some even have inflation cylinders with carbon dioxide, a significant development that was disregarded when BCD inflation bags with valves were introduced. Starting 1969, modern BC's made use of inflation gas in addition to the oral inflation tube that was used to save gas. Concurrent BC models were introduced in 1971, when the Stabilizer jacket of Scubapro was developed and introduced to professional divers. Recent model innovations of BCD equipment have weight pouches with adjustable underwater altitude, heavier weight on the BC than on the weight belt, and more advanced regulators. As for wing innovations, modern BCD equipment include weight pouches with stainless steel backplate.

Meanwhile, all BCD equipment contains a bladder that can be mechanically or manually inflated. Manual inflation works when divers blow air through the one-way valve into the bladder. Mechanical inflation, on the other hand, is done by simply releasing air from the tank into the BCD equipment. Aside from the bladder, air from the BCD is released through a controlled purge valve that is commonly situated on the lower back side of the equipment.

Furthermore, there are three distinct types of BCDs available today. The first type is the front mounted, which is regarded as the least preferred and cheapest BCD model. The air tank of this type is worn separately using a harness, with the BCD bladder on the chest. One disadvantage of this type is that it has the tendency to flip divers on their back. The stationary type with a front mounted BCD can also be frustrating since it does not allow divers to see once they are on the surface.

Another type of BCD equipment is the back mounted. This style is designed with the bladder placed on the diver's back. The acclaimed advantage of this model is that it properly and securely positions divers underwater, so they can be on their stomach. Its disadvantage, however, is that it can cause certain problems once divers are on the surface.

Finally, the jacket style is considered the most common model of BCD equipment today. By its name alone, it is obvious that this model is mounted like a jacket with the bladder basically located on the sides of the BCD equipment. Unlike the two other types, the jacket style does not flip over and it allows both swimming on the front and on the back once divers reach the surface.