The BCD (buoyancy compensator device) is usually one of the first big purchases that a diver will make when committing to owning all of their own gear. This will hopefully be a helpful guide into identifying features and making a decision on which BCD will best fit your needs as a diver. The first part will be understanding the differences between different styles of BCD’s, then we will focus on features. One thing we want to realize is that not all BCD’s are created equally and although almost all brands will produce bcd’s that function properly what they are being used for will greatly affect their usefulness.
Lets first get familiar with the different styles of BCD’s, I am going to break them down into 4 main categories that most shops will carry some assortment of. These four BCD styles are Jacket, Back Inflate, Travel, Backplate/ wing & harness. The two styles jacket and back inflate are what would be considered general or all around recreational BCD’s while the travel and Backplate are considered more specialized having a much narrower usage generally.
Jacket Style BCD:
The Jacket style is usually the first BCD that most divers encounter almost universally being used in rentals for dive shops. The get their name because they wrap around you like a jacket and the entirety of the bcd is a bladder. So air will fill the full bcd around the back and front. This is almost always the best budget option (which is why it is used for rentals) simple design and functioning in all environments. The downside to this style of BCD is when in flawed the Jacket tends to squeeze the user, which if adjusted to tightly or sized wrong can be very uncomfortable for the diver. The benefit of this style of BCD is when inflated at the surface it easily keeps the diver head up. This is a great option for divers on a budget or divers that will not be diving as often because they are generally not the most comfortable.
Back Inflate Style BCD:
The back inflate style BCD generally offers all of the same features of the jacket style bcd with a different style of bladder system. This one is exactly what it sounds like the bladder instead of being wrapped around the diver is attached to the back of the harness. This means that there is no squeeze when inflating the BCD. It also will give the diver better positioning in the water while diving because the bladder is oriented on the back around the heaviest object the tank. Divers that are new to the back inflate often complain that at the surface it tends to push you face down, this is true but can be easily remedied by leaning back on the bcd like a recliner. These tend to be more expensive than the jacket style BCD’s and in my opinion worth the money for the increased comfort and fit that is gained with the back inflate style.
Travel Style BCD:
The travel style BCD more often than not will closely resemble a back inflate style but with smaller features. These BCD’s are meant to be light weight for travel, so reduced weight and lift capacity. This is great for warm water destinations where the user is not wearing a thick wetsuit and does not need a great deal of weight. Most of these travel BCD’s will generally weigh from about 4-6 lbs while the standard jacket or back inflate will weigh from 7-10 lbs. So the Travel BCD’s are not well suited for cold water diving. If you are a diver that will only be doing diving while traveling these are great options. Much better quality and comfort than the BCD’s that you might rent while on a trip. They tend to be in-between the prices of a jacket and back inflate style bcd despite being far less material than either.
Backplate/wing & harness style BCD:
The Backplate style BCD is generally focused more towards technical diving but can obviously be used for recreational. They use either a steel or aluminum backplate with nylon webbing for a harness and some kind of rear mounted bladder attached. These types of BCD’s are very customizable usually set up very simply with few bells and whistles for the diver to add on later if they choose. They can be set up for single or double tanks (usually technical divers), with or without weight pockets and the size of the bladder can be exchanged for a larger or smaller one. The benefit of the backplate is the weight, most steel backplates weight about 5-6 lbs meaning divers can remove that much weight from their weight belt or pockets. If you are looking to get into technical diving this is definitely the best option.
Features: This is something that is hard to cover thoroughly because while most BCD’s will have all of these features each company will have their own take on them, the largest differentiators will be the Quick release weight system and the inflator. Beyond those two they are all fairly similar with a few outliers.
Quick Release Weight system: This in my opinion is one of the most important features to be aware of when purchasing a BCD with the exception of the backplate because they will be an optional add on. Almost all new BCD’s will have their own version of this feature and the reliability of these pockets are paramount. the difficult part of this is that the pockets need to be very secure when the diver is diving, the pockets should not come out unprompted, the locking mechanism holding the pockets in place should be secure (thank god they stopped using velcro it wore out so quickly). But the pockets should also not be so secure that they are impossible to release the weights in an emergency. It is a very fine line that I think few brands get right. In my years of diving I have found that there are a few brands that i find their pockets lost on the bottom much more frequently than others, while this could be user error I personally believe it is an inferior quick release mechanism.
Inflator: This is something all modern BCD’s will have and they all function the same there is a corrugated hose attached to the bladder and on the other end there is an inflator that the LP hose attaches to. There are two buttons one to inflate the BCD usually the one closest to the corrugated hose and a second button to release the air usually on or near the end. Each company will have their own little flair to the inflator with colored buttons or different shapes but for the most part they are interchangeable, you can even get generic ones that fit most corrugated hoses. For the most part this should not be a major factor in deciding which BCD to get each brand will have the same inflator on all of their BCD’s no matter the style. With the exception of Aqualung and their i3 system which integrates the inflator into the bcd and uses a switch on the left side to inflate and deflate, personally I am not a fan, to many moving parts to trust and not easily serviced but some divers do like them.
Tank Straps: These are what attach the Tank to the diver and usually use a standard cam buckle system with the exception of a few brands that have a metal pin latch system. BCD’s will usually have 1 or 2 tank straps depending on the brand, the ones with 2 straps generally secure the tank more efficiently preventing it from feeling like its swinging around. The BCD’s that have a single strap will usually have some sort of plastic backplate that the strap grips the tank to reduce this swinging feeling. Oftentimes with travel BCD’s to reduce weight they minimize this plastic plate with a single strap and add a second lightweight velcro strap to secure the tank slightly more. All of these are functional options that serve their purpose if the user secures the tank properly, which the sales staff should assist with if you are unsure.
Trim weight pockets: these are pockets usually on the back of the BCD located on or near the tank straps. They are not quick release pockets so only a small portion of weight should be placed in these to help adjust the divers trim while underwater. these are very popular for back in late BCD’s because all of the buoyancy is on the divers back. Personally I don’t find them useful, some can be removed if attached to the tank strap webbing which is what I generally do. But if you are a diver and you need to add more weight and have maxed out your quick release pockets and refuse to wear a weight belt this may help pack on those last few pounds. With that being said if you are diving maxing out all of your pockets with weights you should either dive a larger bcd with more lift or a weight belt/harness.
D-rings: these are attachment points for accessories they will vary from BCD to BCD and the number you may want or need could vary. The more technical style BCD’s will generally have more or the ability to add more while travel BCDs will be very minimal with only a few. Once again this is not a feature that i would choose a BCD on but to some divers like photographers it is handy to have more places to clip essential items.
The cumber bun: This is where you tend to see a divide between divers, the comber bun is a velcro strap that wraps the bcd around the waist of the user, there is usually a clip around the outside of the bcd as well that keeps the front pockets from dragging or swinging out when inflated (jacket style BCD’s) I personally find that the cumber bun secures the BCD comfortably to my body, while some divers find it unnecessary, it is a personal preference. Most Travel bcd’s and Backplates will not have a cumber bun, while most jackets and back inflates will.
Dump valves: There are multiple dumps on most BCD’s to release air from the bladder, in addition to the dump on the inflator there is also one at the top of the corrugated hose that is attached by a wire to the base and can be pulled on to use. Most non technical BCD’s will have rear dumps near the base of the bladder for when a diver is inverted needing to release air. Some will also have a dump on the right shoulder with a string to release air, if you are looking for option on where to release air depending on your body position pay attention to the dumps. Personally I find the inflator dumps the most useful and rarely use any other unless I am assisting a student that has not released sufficient amount of air.
I hope this has been helpful in guiding any diver to make an informed choice on their BCD.