Chapter 7- Search and Recovery
Search and Recovery
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FIGURE 7-3. Lift bags come in a variety of designs and sizes. It is important to match the bag to the item being lifted.
if you can simply write a message to convey your point.
Draw the search area on the slate before you start and
mark off each area as you search it.
Even better is the use of underwater radio communications
so that you and your buddy and others on the
team can simply talk to each other. These devices are
readily available, reliable and becoming a popular addition
to many recreational diver’s equipment.
To define an area to be searched or to keep track
of what has been searched, surface floats are often used.
These are a form of marker buoy, but are larger and
more positive indicators than smaller marker buoys
designed to be carried by a diver. The larger float is easier
to see at the surface, and can deploy a heavier anchor
that provides better holding power. Surface floats can be
anything from a plastic jug to a specially designed buoy
as long as the purpose of defining and maintaining the
search area is fulfilled.
Perhaps the most specialized item of equipment
for search and recovery operations is the lift bag (figure
7-3). The bags are made from different materials, and
the type of material isn’t important as long as the bag
holds air underwater. The neck of the bag is fairly narrow
and usually has a strap attached for rigging the
bag to the object being lifted. A desirable feature on
a lift bag is a “dump valve” – a manually operated valve
that allows expanding air to be vented from the
lift bag during ascent. This is one way in which a lift can
be controlled.
An extra source of air should be used for inflating
a lift bag underwater. Use of the diver’s primary regulator
second stage is not recommended. The regulator
could become entangled in the lift or get caught as the
lift begins to ascend. Being pulled to the surface with no
source of air is a potentially hazardous circumstance and
one that can be avoided by use of an extra source of air.
The use of a separate cylinder of air to fill a lift bag is
recommended, although use of a regulator’s extra second
stage is permissible if care is taken to avoid the potential
for entanglement and adequate air supply is available.
The potential for entanglement can be reduced if one
diver holds the bottom of the lift bag open while the
other adds air to the bag. Also, do not push your hand
up inside the lift bag while adding air.
TECHNIQUES AND PRECAUTIONS
You are now familiar with the basics of what to do,
but you need information on how to do it. This part of
the chapter will explore the appropriate techniques to use
and will help you learn about potential hazards involved
with search and recovery so you can avoid them.
Again, your first step is to mark the starting point.
The use of a marker buoy was suggested, but what if you
don’t have one? Then a “fix” of the position as described
in the chapter on navigation should be taken as quickly
and accurately as possible. Even if there is absolutely
nothing visible that can be used as a reference, you
should still write down any information that can help