Alarms and alarm systems are often an integral aspect of a Human-Machine Interfaces (HMI), along with displays and controls. An effective HMI should support optimal human performance.
Alarms help personnel to maintain a system or process within a safe operating ‘envelope’ and help them recognise early and respond to faults, malfunctions or abnormal conditions.
An alarm can be defined as an audible or visual indication of an equipment malfunction, process deviation, or abnormal condition requiring a response by a person.
A key point is that every alarm should have a clearly defined operator response. If a response cannot be defined, then the signal generated by the Human-Machine Interface should not be an alarm.
Ineffective alarm management has often been cited as a contributory factor in major accidents around the world. Alarm management refers to the processes and practices for designing, operating, monitoring and maintaining alarm systems.