bc question

[mer-maiden]

So I have a question about bc's. While doing my pool part of the instruction my instructor put me in an extra small bc. I'm a small girl but I've got a few well hidden lbs on me and I had an uneasy feeling about whether or not the bc would be able to hold me up. Not ever using one before I didn't really think it was a good thing to question the instructor. I figured he would know better than I would about such things. My question lies in the fact that I really do think that I need a small vs. the extra small. I am planning on going back to the pool this week to try the small and practice taking my mask off underwater. How will I know which size bc is better for me? Thanks for any advice you can give me! -Sarah

 

[kent_1848]

Pick your BC on how well it fits. The size is just that, it is like a jacket. You wouldn't buy an extra large rain coat, just because there is more material there to protect you from the rain when an x-small will do the same job of keeping you dry. While there are differences in the amount of lift supplied by a x-small and a small bc, they are miniscule. If the BC will keep you and your equipment (including weights) afloat, then you are fine.

 

[Marek K]

How will I know which size bc is better for me?

Hi Sarah--

Like kent_1848 said, the difference in lift almost certainly won't make a significant difference for you. It's all going to depend on fit. How did the XS fit?

I assume you're using conventional jacket-style BCs. The cummerbund (wide padded band around your waist with velcro closure) should fit snugly, below your rib cage -- not at your beltline, like you may assume... the bottom of your rib cage holds it in place.

The cummerbund's velcro should be somewhere in the middle of its adjustment range when snugged up, as should the shoulder straps; not at one extreme or the other -- you're going to want some adjustment room, particularly to tighten down in the water.

And like kent_1848 also indicated, the decisive factor in deciding whether a BC is the right size, is going to be whether it "holds" you well when inflated at the surface, without slipping up around your head (or, rather, allowing your to slip down into the water inside of it). That doesn't necessarily mean when fully-inflated; but enough so that your head is comfortably out of the water.

You're fortunate, in that you're going to be able to start judging what you like and don't like, and what sizes fit... but a big factor for the future is going to what kind of exposure protection you're going to be wearing in open water; a thick wetsuit will make a big difference in BC fit. And also remember that there are no "standard" sizes... one manufacturer's XS may fit you, and another's S.

Oh... and it's absolutely appropriate to ask questions of your instructor, when you don't understand the what and why of things... as long as you don't become a "spring-butt," or sound like you're challenging him/her.

--Marek

 

[lorien]

I agree that it is important that the BC fit you correctly. Also important is the amount of lift that the BC has but as you are a small woman that probably will not be as much of a consideration. However if you start diving in cold conditions that require a lot of neoprene or a dry suit you need to consider the amount of lift that your BC has as you add extra weight to compensate for your exposure protection. A good fitting BC that has sufficient lift for your needs is what you are looking for. Your instructor should be willing to discus this with you and help you feel more comfortable.

 

[mer-maiden]

Wow. Thanks. It seems like I was more concerned about the diff in bouyancy in the two sizes but since it seems like there really isnt one than it just becomes a matter or which feels better. The extra small felt really tight around my ribcage and it was a lil difficult getting my arms in. Thanks so much for the help!!

 

[Marek K]

However if you start diving in cold conditions that require a lot of neoprene or a dry suit you need to consider the amount of lift that your BC has as you add extra weight to compensate for your exposure protection.

Yes but, ideally, Sarah would only add additional weight to compensate for the extra buoyancy of a thicker wetsuit or a drysuit; it should (ideally) be a net wash, as far as needing more BC-related buoyancy.

Problem would be if she over-compensates for extra buoyancy, by having too much weight. Which, as I'm sure you'd agree, would most-likely happen at the beginning. So that would be a consideration.

--Marek

 

[redrover]

So I have a question about bc's. While doing my pool part of the instruction my instructor put me in an extra small bc. I'm a small girl but I've got a few well hidden lbs on me and I had an uneasy feeling about whether or not the bc would be able to hold me up. Not ever using one before I didn't really think it was a good thing to question the instructor. I figured he would know better than I would about such things. My question lies in the fact that I really do think that I need a small vs. the extra small. I am planning on going back to the pool this week to try the small and practice taking my mask off underwater. How will I know which size bc is better for me? Thanks for any advice you can give me! -Sarah

SARAH,

I’m not an expert but a newbe too. Just sharing my experience. In my class a very thin lady, was uncomfortable with her X-S, sounded kinda like you said. They brought out a S to try and pointed out why it didn’t fit well, put her back into the XS and pointed out where and why it was better. At the end of class she mentioned that she was more familiar with how they worked now and she was happy with the XS.

I was put in a vest BC 1st pool and noted it was a S for when choosing to purchase. This was surprising as I’m not usually a Small in general sizing. I’m short but not little with a thick rib cadge and wear a Med or Large often in Women’s, but Smalls in men’s sometimes.

Next pool class I felt things were not connecting right and asked my instructor about it. It took me a moment as he was busy with other people and I was embarrassed assuming I was doing something wrong. Turns out I had been assigned an Extra Small, it was too small and quickly was replaced. (They apologized and offered to disconnect and reconnect but I declined thinking a good opportunity to practice the set up.)

One reason I chose the BC I did when purchasing was it had adjustability. My weight does fluctuate and I also worried about being where I’d use a thicker wetsuit.

Do talk to the LDS and try on different sizes and ask them to explain what they are seeing about the fit.



Thanks Mare K for the cummerbund fit point. I’m still wondering about my choice and your help explains better how tight I should put it. I did assume it should have been riding lower and when I tried others they did. Once again I’m reassured I made a good choice for me.

 

[lorien]

Yes but, ideally, Sarah would only add additional weight to compensate for the extra buoyancy of a thicker wetsuit or a drysuit; it should (ideally) be a net wash, as far as needing more BC-related buoyancy.

Problem would be if she over-compensates for extra buoyancy, by having too much weight. Which, as I'm sure you'd agree, would most-likely happen at the beginning. So that would be a consideration.

--Marek

Maybe ideally However, that wetsuit will compress at depth and lose some of its buoyancy as well. Many women's BC's have low lift capacities, really low. Most men's BC's don't seem to have such low lift capacities. Now this seems like a smaller woman and maybe she need not be concerned but it is something to keep in mind.
Here is some info on lift that I found, explains it far beter than I ever could.:
"A general rule is this: Your BC should be able to hold you comfortably at the surface, without any kicking, in all your gear, while only halfway inflated. How much lift is that? Your mileage will vary. For instance, if you plan to do freshwater diving, you'll need more lift than for marine dives, since saltwater is more buoyant. For tropical diving (sans wetsuit) you'll need a generally-recommended 12 to 24 pounds of lift, for temperate diving (requiring a wetsuit) 20 to 40 pounds, and for hard-core or technical diving, 40 to 80 pounds (but then, you should know if you do this kind of diving). Buy a BC to match the most demanding diving you plan to do, and don't skimp on Lift. The surface can be a long, long way away when your suit is compressed by deep-water pressure and that tropical BC isn't up to the demands your cold-water dive is making on it. "
Just another thing to consider.