A fire water system on an oil rig is supplied by an electric motor driving a
mechanical pump. A fire detection system is installed that normally starts
the motor automatically but which can be set to manual override. The
electric motor is normally supplied by the mains power source but it does
have a standby generator for emergencies.
(a) State as a consequence of failure of the pump or motor or detection
system, the top event. (It may assist you by referring to FIGURE 4.)
(b) Complete the table for the cases of deviation/failure shown, that is:
(i) pump failure
(ii) motor failure to start
(iii) fire detection system failure
(iv) motor power supply failure
arising from any associated equipment failures or events that would
cause the failures from the data given. Indicate whether the
associated events are linked by OR or AND operators.