Dynamic alarming describes various techniques for eliminating alarm floods through automatic suppression of redundant and consequential alarms resulting from a significant equipment failure or process disturbance. Alarm flood suppression and first-out alarming are the two most common techniques used in dynamic alarming.
Alarm flood suppression logic monitors process conditions to detect a significant equipment failure or process disturbance. When detected, a single common alarm is presented to the operator and all of the expected consequential alarms associated with the event are suppressed.
First-out alarming permits the first occurring alarm in a related group of alarms (a single process event) to annunciate while suppressing the remaining alarms in the group. For example, an equipment shutdown causes a cascade of alarms that overload the operator and make it difficult for him to determine the initiating cause and therefore take appropriate corrective action. With first-out alarming implemented, the operator sees only the first occurring alarm while the other related alarms are suppressed. Now the operator can quickly take the appropriate and corrective action.