New to Scuba

[DivingGal]

Originally posted by animian2002
Oop

Right...that 's the word - buoyancy.. .....

Like any good story you start off with a "In the begining I used xx pounds..." as the story proceeds, you soon will be removing weight.

As FunckyMunks says, the more you dive, the more you'll eventually be able to remove. Then you'll be like your instructor adjusting your buoyancy with your BCD.

DO NOT HOLD YOUR BREATH!!!! This can lead to major problems.

Excitement is a factor with all all new divers (even some experienced ones) Retaining air because you don't exhale all the air in your lungs. Neither FunkMunk or I mean that you're holding your breath.

When u/w I use long slow breaths in and out. It's all a question of being comfortable and relaxed u/w

 

[Spectre]

Originally posted by animian2002
I thought the key point is we are not supposed to hold our breath underwater and in order not to do so aren't we supposed to slowly exhale..

Ok... the holding your breath thing. The reason you are taught to constantly breath is because people naturally lock off their airway to hold their breath. This is a problem on two sides of the coin. First, when your holding your breath, you usually have your lungs full. When your lungs are full and your bouyancy is right, you will be positively bouyant at that point. Now if your holding your breath, and your positively bouyant, your going to rise some. As you rise, the air in your lungs expand, and since you have your airway locked, it's going to end up damaging your lungs. The deeper you are, the farther you can rise without damage, and likewise the shallower you are, the more dangerous it is [a 3 foot rise at 15 fsw with full lungs is enough to rupture your lungs].

So as long as your breathing, your lungs aren't locked off, and if you ascend while breathing, the expanded air just goes out. Much like what will happen if you take a deep breath, breathe out slowly, and then push on your chest... you will just breathe out faster.

Now to go a little beyond, but something to think about, there is a big difference between 'holding your breath' and 'stopping breathing'. I'm not recommending you do this by any means, but one can 'stop breathing' at which point your airway is still open so expanding air can escape. Try it while you sit there. Breathe in deep and lock your airway. Push on your chest. No air comes out. Now breathe in deeply but just stop breathing and see if you can keep from locking your air. if your breath is too deep, you will exhale some anyway, once the natural chest compression has completed, push on your chest with your hands... if your airway isn't locked, you'll force air out of your lungs.

Once you start getting comfortable in the water, and you understand you can breathe at the bottom of your lungs to descend, full breaths once neutral, and high breaths to rise some to get over stuff, people sometimes start what is called 'skip breathing' to conserve air.

skip breathing is holding your breath between breaths, in the middle of the breath. I'm not going to get into _why_ this is bad, but trust me... you don't want to do it [it gets into CO2 build-up and all of that]. When it comes time to work on your air consumption, just slow down your breathing, but constantly breath. When I'm really relaxed I find my breath cycle is around 25-30 seconds.

The moral of the story, think deep slow breaths, and deep is really key for getting the weight off...

 

[Spectre]

Originally posted by animian2002
is it got to do with the way we inflate or deflate BCD. the instructor and assistant seem to be doing very well under water...how do they do it ...

Let me get back to your original question... how to get yourself under control now. First off, when you are having 'floating' issues, do you have air in your BC? If your BC is empty and you are still having problems, then you really are going to have to add a little more weight until you get more comfortable. Now if it's that you put air in your BC, and then you end up becoming positively bouyant, the key is to inflate slowly. I tend to give a little blast, breath deep [to see if I start to rise] if not, give a little more air, take another breath, repeat until neutral.

You should be learning the fin-pivot, or some other sort of 'getting neutral' drill. This will definately help. By the time I was done with my pool and OW dives I no longer needed to use the fin pivot to calculate out neutral bouyancy. It was only a couple more dives before I got to a point where I could get my bouyancy right as I was decending, so by the time I reached depth, I was already neutral. Just remember it takes a little bit of time for the effect of inflation/deflation to get your mass moving, so be patient. little blasts or little dumps and wait a second to see the effect.

However if it is that you just can't stay in control with an empty BC, the only immediate answer is to add weight. After you get comfortable that extra weight'll come off. I know the first pool dive I did I was wearing close to 40 lbs in fresh water. I now wear 30 in salt, and could probably take off more.

One other thing to remember. If you have the 'perfect' amount of weight when you are starting your dive, you need to still add another 3-5 lbs to offset the bouyancy of your tank at the end of the dive. The last thing you want is to be fighting the bouyancy while your doing a safety stop at the end of a dive.

 

[chrispete]

I had the same problem of rocking side to side having a hard time "balancing" - even though the weights were evenly distributed on the belt, it didn't help much. I found that by pulling a couple of pounds off of my back and moving it to my front/sides greatly increased my stability underwater (but had me fighting to keep my face out of the water topside) and helped me to become comfortable with basic bouancy skills. What eventually happened is that I got comfortable with my bouancy in later classes and moved the weights back to their original place, and it was much, much easier to control at that point - in fact, I now seek some instability (if I stop moving and exhale, I like to begin slowly rolling over, with the tank seeking the bottom) with this setup, I am much more manuverable underwater.

Bottom line: don't be afraid to play with the weights and find what's best for you - your instructor has a ton of experience, and can lead you down the right path, but ultimately it is you diving in your skin and not him - if it doesn't feel right, try something different

 

[JamesK]

Originally posted by chrispete
in fact, I now seek some instability (if I stop moving and exhale, I like to begin slowly rolling over, with the tank seeking the bottom)

Why would you want your tanks to start to pull you over when you stop? When you are hovering looking at something, why fight to stay in the proper trim?

 

[devilfish]

Originally posted by funky__monks


The deeper you are, the farther you can rise without damage, and likewise the shallower you are, the more dangerous it is [a 3 foot rise at 15 fsw with full lungs is enough to rupture your lungs].

Actually 3 ft of change in pressure is the same at any depth. On a full lung to limit of expansion the same damage would occur on a 3 ft rise regadless if it is at 15 ft or 90ft.

 

[chrispete]

After my dive this afternoon, I'm seriously rethinking the instability thing, I got used to diving in really bad viz (2-4 ft) in training and we basically went full speed ahead until we bumped into something interesting - the instability worked for me in that situation. This afternoon I dove in water with better viz and the pace was much, much slower than I have been used to, and I did have a lot of trouble because of the weighting that I was using - I'm going to take my own advice from my earlier post and move my weights around to a different configuration that is more stable...

 

[devilfish]

Originally posted by chrispete
After my dive this afternoon, I'm seriously rethinking the instability thing,

It is common for beginning divers and even divers with experiance to be overweighted. This causes a whole bunch of problems.
A diver with too much weight must
compensate with a lot of air in the bc. The slightest movement to eiter side shifts the air in the bc and rolls the diver to one side or the other. To stabilize causes exertion which makes the diver breathe heavier. This causes buoyancy problems. On the next dive a diver puts on more lead to compensate for heavy breathing. More lead causes the need for more air in the bc. That causes greater shifts of air, causes heavier breathing, and on and on and on, thus never ending compensation chase.
Buoyancy control vs neutral buoyancy are two diferent concepts.
I suggest to take a good buoyancy control class.

 

[animian2002]

Hi, I'm back from my second pool session.

I tend to give a little blast, breath deep [to see if I start to rise] if not, give a little more air, take another breath, repeat until neutral.

we were practicing how to maintain neutral buoyancy.. the thing is now I have no problem "sinking" but problem with maintaing neutral cos I notice that I rise much faster then I sink.. . as per my instructor it is all abt the control of my breathing..which I still couldn't get the hang of it.. :upset:

another thing, we were practicing removing our BC and tank in the water and wear it again in the water. I find that rather difficult as they tend to float around cos of the buoyancy and "refused" to let me put it on. I have a hard put it on but managed to do it. Is there a "easy" way to do it

and one more...I have learnt from the other thread ,pple tend to throw up when they reach the safety stop when ascending...so as a beginner ..am I to restrain from food when I dive??

I'm going for the open water today and we are to go thru all those we have learnt during the pool session...hope fully I can do if not I'm in deep trouble ..

that's all

Ciao

 

[scubaaz]

If I got this right ------ You are having a problem staying upright when diving in a horizontal position??

If so, adjust your weights so the heavier weights are on your stomach side and the lighter weights are on your buttocks side.

This will trim the weight distribution and allow you not to roll left or right. Experiment in full gear in a shallow pool to get it just right. Practice the ol' fin pivot.

Good Luck