4.1.2-1 Assured Functionality Under High Alarm Conditions

The alarm processing system should ensure that alarms that require immediate action or indicate a threat to plant critical safety functions are presented in a manner that supports rapid detection and understanding under all alarm loading conditions.

Additional Information:
Alarm processing should be provided to ensure that alarm functional criteria are not lost under any operational or accident conditions. The alarm system should provide the capability to reduce the number of concurrent alarm messages so that during off-normal conditions, the alarm system does not overload of the operator's cognitive processes. Special attention should be given to the problem of detecting subsequent malfunctions following the presentation of alarms related to an initial disturbance.