SECURE IT
There are several
options available for
how and where to
secure your weights. A
weight belt is the most
common method of
wearing weights; there
are belts that accept
slide-on weights as
well as pocket belts
that can accommodate
either solid weights
or soft weights (bags filled with lead shot). Weight
belts are easy to ditch in an emergency as long as
you keep other gear clear of the belt. A shoulder
harness is sometimes used when the buoyancy of
thermal protective suit requires more weight than can
comfortably be worn around the waist.
Integrated weight pockets and harness systems
offer a couple of advantages over belts: They can be
considerably more comfortable, and they offer improved
ability to adjust trim. But unlike belts, which have a
single point of release, harnesses and integrated systems
may have more than
one release point. This is
crucial information for
the diver and dive buddy
to discuss prior to diving
— and to remember
in the event of an
emergency. A downside
to using weight pockets
is that it may be more
difficult to add or remove
weights if adjustments
need to be made.
STAY TRIM
In addition to wearing the right amount of weight,
make sure it’s positioned to optimize underwater trim.
Creating a level profile in the water makes you more
hydrodynamic. Distribute the weights as equally as
possible from side to side; you should never feel as
though you are listing to one side while diving. You
should also consider the weight of your scuba tank
and the style of your BC when placing your weights.
The tank can be moved up or down in the tank band
to facilitate optimal body positioning in the water.
Back-inflation BCs have a tendency to push the diver
forward (face down) in the water, so placing weights
toward the back can help to counter some of this
forward pitch, especially at the surface. While weight
pockets on the back of your BC can help with trim,
they also present a hazard in an emergency because
buddy assistance is required to remove them if
ditching weight becomes necessary.
Fins can be positively, neutrally or negatively
buoyant, and each type may require compensation.
Ankle weights can help offset a more buoyant lower
body half, but they may be a challenge to ditch,
because you have to reach to release them. If your fins
are negative and create a downward pull on the lower
half of your body, moving weights higher on your body
or shifting your tank higher in the band can move up
your center of gravity to promote a more level profile.
Reviewing where and how your buddy’s dive weights
are placed is an essential component of every predive
check. Each buddy needs to know how to jettison the
other buddy’s weights in an emergency.
Learning to determine proper weighting will
enhance your enjoyment of dives as well as your
safety. Having a good understanding of your baseline
weighting needs and the factors influencing your
buoyancy will aid you in adjusting to a variety of
environments and conditions.
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HOW TO PERFORM A BUOYANCY CHECK
Start in water too deep to stand in, and release all the air
from your BC. Inhale a normal breath, and the water should
be at eye level. When you exhale, you should sink so that
the water is just over your head and then rise to eye level
as you inhale normally again.
Adjust your weights in small increments (e.g., two pounds
at a time). Consider adding a little extra weight to offset
the potentially positive buoyancy of a partially emptied
aluminum cylinder at the end of the dive.
If you are properly weighted, you should be able to hover
effortlessly at 15 feet at the end of your dive with 500 psi in
your aluminum tank and no air in your BC.
STEPHEN FRINK
STEPHEN FRINK
