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Wednesday, May 27, 2009

How to Determine the Proper Amount of Weight Needed for the Dive

Divers take the weight belt and systems for granted more than they should.
This is the system that allows them to have a safe and comfortable dive. Too much weight and you are always struggling to maintain buoynancy, too little weight and the descent to start the dive will be difficult.

HOW MUCH WEIGHT IS ENOUGH ?

Before going on the first dive, we teach divers to do the weight and buoyancy test. This is how the test is performed. You will have to enlist the help of other divers to help with this test. You will start off with some weight in the BCD. Thew dive shop or instructor will give you a basic guide to how much. This depends on a few factors: what type water you are diveing be it salt or fresh water, also how much weight you are. Are you thin, heavy, or in between. Keep in mind that this is a starting weight.

To do the test. You will need to enlist the help of other divers to hand you weight etc.

1. Enter the water with all the gear and your estimated weight. Get in water that is over your head but not far from the exit and shore.

2. Make sure that all the air is out of the BCD. Keep the regulator in your mouth, and hold a NORMAL breath of air. Be ready to kick up if you begin to sink. This is where the help is needed.

4. You should float at eye level. If you do not, add or suntract weight till you are. You can just hold the weights till you figure out how much. Then once you do you can intergrate them into your BCD or Weight belt.

5. As a final check, exhale. You should begin to slowly descend if you have the proper amount of weight. You should also raise the deflator over your head with your left hand. This will also help you decend, because now you are using the weight of you arm to help with this.

6. Once you have dtermined the weight to this point, you will need to add a small amount ot EXTRA weight (about 2 pounds)

Why ? Air has weight. As you use the air in your tank the tank begins to become lighter and more buoyant. Add ting extra weight will off set the buoynacy factor that you get by the end of the dive.

HOW DOES THE WEIGHT AFFECT MY DIVE UNDERWATER ?

Weight also has a direct effect on how often bouyanct adjustments are made. If the diver carries more weight than needed to "help get underwater better". they also have to add more air to the BCD as they dive to ofset the extra lead weight added on the surface. Now the volume of air exchanges with depth, this causes a greater changes in buoyancy, which causes a diver to adjust the air in their BCDs more often.

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