Except of course that the petite diver (unless they choose to wear the XL divers exposure protection????) does not demand the same lift characteristics.
JACKET vs. BACK INFLATE BCDs- which and why?
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Except of course that the petite diver (unless they choose to wear the XL divers exposure protection????) does not demand the same lift characteristics.
Except of course that the petite diver (unless they choose to wear the XL divers exposure protection????) does not demand the same lift characteristics.
Not necessarily. A BCD needs to compensate for the gas in the tanks and exposure protection compression (for wetsuit divers). However, many divers also want their BCDs to float their gear on the surface without them.
In cold water diving, I've seen more than one petite divers gear sink as the result of their BCD providing not enough lift. If the BCD has the same lift as their larger counterparts, this would not have been an issue. Granted, all these have all been weight integrated BCDs, and these divers chose to put all their weights in their rig. But given that "no weight belts" is a selling point for weight integrated BCDs, I can't lay all the blame on the diver.
AbyssalPlains
Contributor
rstofer
Contributor
Yup!
The BC (of whatever type) needs to be capable of supporting itself, any integrated weights and whatever else is clipped on floating by itself.
The diver needs to float with any attached ballast and misc stuff in pockets without the BC.
For the cold water, wetsuit diver, having all the weight integrated probably doesn't work unless the bladder has a lot of lift. However, the diver can wear almost all of the ballast without sinking the wetsuit.
For the warm water diver, the weight should probably be integrated. The bladder will easily support it and the diver will usually sink wearing the weightbelt without the BC. But if there is a thin wetsuit involved, some of the weight can be moved off the BC.
The wing needs to provide at least as much lift as the loss of buoyancy of the wetsuit plus the weight of the air when the tank is full. More, if the diver is overweighted.
The possibility that extra small BCDs provide insufficient lift needs to be evaluated. Particularly for the cold water diver. The deeper you dive, the less buoyant you become (wetsuit compression) and the more lift you require from the bladder.
Richard
As a warm water diver who has never dove with all my weight integrated, I'm having a problem agreeing with this statement. If I am neutral at the surface with just WS and WB why would I sink without the BC. I can see 4-8 lbs in trim pockets but my recreational weight belt keeps me neutral (or minimally positive) at the surface, so I don't sink without the BC.
rstofer
Contributor
As a warm water diver who has never dove with all my weight integrated, I'm having a problem agreeing with this statement. If I am neutral at the surface with just WS and WB why would I sink without the BC. I can see 4-8 lbs in trim pockets but my recreational weight belt keeps me neutral (or minimally positive) at the surface, so I don't sink without the BC.
My view of warm water diving is T-shirt and shorts. Without a wetsuit, almost any ballast will make the diver negative.
There is a progression through buoyant wetsuits. Some cool/warm water divers use a 3mm suit and this will obviously support some amount of ballast. But this is the same for heavy wetsuits. The diver can wear as much ballast as they want as long as they are neutral or slightly buoyant at the surface without the BC. I would prefer to be head high at the surface and this might be as much as 10# positive.
The additional weight required to sink the diver can come from any combination of trim weights, a negative backplate or a negative tank. The total of these should not exceed the flotation of the BC.
The final consideration is the weight of the BC when ballast is integrated. I would prefer not to have to lift a 43# tank, 20# of ballast, a 6# plate and a 2# regulator - around 71#. As I am using a 7/8mm wetsuit, I carry the ballast in a separate harness. My wetsuit will float the harness and my wing will clearly float the rest.
Richard
We get plenty visitors and residents here who need some weight to sink, even in t-shirt and shorts.
And here I thought kelp divers considered anything above 69 deg as warm water
The image of divers that can not ascend without the assistance of a lift bag doesn't seem very recreational to me.
Rule # (1) Fit is the most important feature when selecting gear. If your gear fits you correctly you will be more comfortable and relaxed.
Do you need to have zippers and pockets everywhere? Think about your needs and the type of diving you'll be doing, diving doubles or single tank? Think about the exposure suit you might wear, wet or drysuit? How will this relate to how the BC fits your body? Do you like the feeling of being wrapped in a BC or would you perfer a more open and free feeling? How long do you plan on diving in this piece of equipment? Scuba equipment should be seen as an investment (costly), take the time to get advice and think it through. What ever you decide take care of it and it will last a very long time.
Do you need to have zippers and pockets everywhere? Think about your needs and the type of diving you'll be doing, diving doubles or single tank? Think about the exposure suit you might wear, wet or drysuit? How will this relate to how the BC fits your body? Do you like the feeling of being wrapped in a BC or would you perfer a more open and free feeling? How long do you plan on diving in this piece of equipment? Scuba equipment should be seen as an investment (costly), take the time to get advice and think it through. What ever you decide take care of it and it will last a very long time.
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