General applicability

This standard is primarily for use with annunciators, devices or groups of devices that call attention to changes in process conditions. Annunciators can range from a single annunciator cabinet, to complex annunciator systems with many visual display cabinets and remote logic cabinets, to computer-based displays. Both hardware and software annunciators are included. The annunciator may also include interfaces to the process historian.

The sequence designations are provided to describe basic annunciator sequences and also many sequence variations. This standard specifies the sequence logic for several standard sequences used for annunciators; however, detailed design requirements and documentation formats are beyond the scope of this standard.

Technical relationship to ISA-18.2

ISA-18.2 (see Clause 2) addresses alarm systems that notify operators of abnormal process conditions or equipment malfunctions that require an operator response to prevent or mitigate related consequences. Many of the principles contained in ISA-18.2 apply also to the annunciators described in ISA-18.1, but annunciators are not restricted only to process conditions that qualify as alarms.

Exclusions

This standard is not intended to be used directly as an annunciator system purchase specification. This standard may be useful in developing an annunciator specification. It will not eliminate the need for sound engineering judgment. No particular technology is mandated.

This standard is not intended to be used for mobile devices that can also call attention to process conditions.