Alarm and Instrument Management

Instruments and alarms are vital components to communicate to the operator whether the process is in or out of control. During normal operation, many instruments and alarms are in service and their functionality can be easily verified. Other alarm systems, however, such as a high-level alarm or any emergency shutdown system, may infrequently or never be activated under normal operation, so there is no assurance that it is still functional.
The process safety management system should also assure that other fixed or portable safety related instruments are regularly tested. Such equipment should be calibrated at regular intervals, with management controls in place to initiate the work. Where these instruments and/or alarms are deemed critical to safe operation, they should be included in the preventive maintenance program. Similarly, any instruments or systems containing sensors that are safety critical and that provide input to computerized control equipment should be included in preventive maintenance program. Also any changes to such instrument or alarm setting outside of acceptable ranges should first be reviewed and approved.
Reference: CCPS(1989) Guidelines for Technical Management of Chemical Process Safety

Management/Mechanical Integrity/Maintenance Procedures