Chapter 2- Continual Improvement
Continual Improvement
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FIGURE 2-8. Maintaining neutral buoyancy and trim improves diving efficiency.
ancy check is that you should float at eye level with all of
your equipment in place, your BC empty, your lungs full,
and 500 psi in your cylinder. Take time on your next dive
to check your buoyancy during your safety stop and make
adjustments. Be sure to record your proper weighting
for your equipment configuration in your log book. This
includes any differing equipment configurations (e.g.
steel v. aluminum cylinders), or environments (e.g. fresh
v. salt water).
You know that the removal of weight is required
when an ocean diver wants to dive in fresh water, and
that a fresh water diver needs more weight for ocean diving.
You can use a rule of thumb to estimate how much
weight to add or to remove when the same equipment is
being used. Here’s how.
Ocean water is two-and-a-half percent heavier than
fresh water, so it provides two-and-a-half percent more
buoyancy than fresh water. When moving from fresh
water diving to the ocean or vice versa, you must add or
subtract enough ballast weight to change your density by
two-and-a-half percent. In other words, you should add
or subtract about one-half kilogram for every 20 kilograms
that you and your equipment weigh (about one
pound of weight for every 40 pounds).
Since most of us have not weighed ourselves with all
of our dive gear, a good place to begin is to add or subtract
one-half kg (one lb) for every 20 kg (40 lbs) of body
weight, plus one-half kg (one lb) for the weight of your
equipment. Round to the closest half kg (pound).
Using this rule of thumb, if you weigh 52 kg (115
lbs), you would add 2 kg (4 lbs) to your ballast weight
when you move from fresh water diving to ocean diving.
If you weigh 93 kg (205 lbs), you would remove 3 kg (6
lbs) when transferring from the ocean to a lake.
Closing the Dive
You have completed the dive successfully and had a
great time. When you exit the water, it is time to disassemble
your equipment, relax, debrief one another, and
enter the dive in your logbooks.
Depending on circumstances you may put your equipment
away, or you may set it up for the next dive. Keep it
out of the way of other divers if you are boat diving and out