Glossary · HMI, SCADA and operations
Alarm rationalization
Also known as: Alarm review
German: Alarmrationalisierung
In alarm management, alarm rationalization is the systematic review of potential and existing alarms against the alarm philosophy to confirm that each is needed and to document its cause, consequence, operator action, response time, priority and limit.
- HMI and SCADA
- Process industry
In one sentence
Alarm rationalization reviews each alarm against the alarm philosophy and documents cause, consequence, action, priority and limit.
Example
In a rationalization workshop, operators and process engineers remove a low-flow alarm that duplicates a pump trip alarm and lower another from high to low priority.
How it applies
- Engineering: Rationalization is usually a workshop with operators, process, control and safety engineers. Inputs include P&IDs, HAZOP results such as Hazard and Operability Study (HAZOP) records, and alarm history.
- Outcome: Each alarm is documented in the master alarm database with its justification. Alarms without a required operator action are removed or converted into events.
- Documentation: The rationalization records are the best source for alarm help texts and alarm response procedures. Technical writers should take cause, consequence and action from them instead of writing new text from the HMI tag list.
Alarm rationalization vs. alarm suppression
Rationalization decides by design which alarms exist and how they are set. Suppression and Alarm shelving hide existing alarms during operation. Rationalization reduces the need for both.