Pressure Relief Power Failure
Power failure will shut down all motor driven rotating equipment such as pumps, compressors, air coolers, and reactor agitators. As with cooling water failure, power failure can have a cascading negative affect on other equipment and systems in the plant. Different scenarios should be considered for this contingency depending upon whether the power interruption is local (to a single equipment item), to a unit substation, or plant-wide. Adequate backup features should be included in the plant’s electrical design to reduce the probability of a major power interruption to an acceptable level.