13.1.1 Cargo tanks shall
be fitted with one of the following types of gauging devices:
-
.1
Open device: which makes use of an opening in the tanks and may expose the
gauger to the cargo or its vapour. An example of this is the ullage opening.
-
.2
Restricted device: which penetrates the tank and which, when in use,
permits a small quantity of cargo vapour or liquid to be exposed to the
atmosphere. When not in use, the device is completely closed. The design shall
ensure that no dangerous escape of tank contents (liquid or spray) can take place
in opening the device.
-
.3
Closed device: which penetrates the tank, but which is part of a closed
system and keeps tank contents from being released. Examples are the float-type
systems, electronic probe, magnetic probe and protected sight-glass.
Alternatively, an indirect device which does not penetrate the tank shell
and which is independent of the tank may be used. Examples are weighing of cargo,
pipe flow meter.
13.1.2 Gauging devices shall
be independent of the equipment required under 15.19.
13.1.3 Open gauging and restricted
gauging shall be allowed only where:
13.1.4 Types of gauging for
individual products are shown in column j in the table
of chapter 17.