A warning system should be provided to indicate a malfunction
which requires immediate attention and which should meet the following
conditions:
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(a) It should actuate a visual warning signal
which can be switched off at the craft's control position. Where the
visual warning will not be immediately evident to the operating crew
member, a sound warning should be provided in addition. There should
be individual light signals at an appropriate control station to indicate
which warning signal is in action.
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(b) It should be designed so as to be protected
against breakdown: in general for this purpose, any fault in the alarm
circuit should either activate the system or some appropriate signal.
An appropriate test facility should be incorporated.
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(c) It should have a permanent power supply and
should befitted with a change-over switch so that it can be connected
to an alternative source of power in case the normal source of power
should fail. An alarm signal should be operated if the normal source
of power for the warning system breaks down.
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(d) The fire detection system should befitted
with an automatic device and when the system comes into action should
activate, at the craft's control position, a visual alarm signal which
is different from all other devices. The fire detection system of
the machinery installations should be automatically fed by an emergency
source of power in case the main source of power should fail.