Alarm Rationalization

When you walk into a control room, you typically experience one of two scenarios: (1) operators are busy, alarms are sounding in the background, and the alarms receive little attention or (2) operators are busy, alarms are not sounding in the background, and alarms receive immediate attention upon activation. One of these control rooms has probably been on the receiving end of an alarm rationalization project.

Alarm rationalization is a key component of a facility’s alarm management lifecycle. Alarm rationalization is the formal activity of identifying critical alarms that need to be managed and then performing the following tasks for each:

     1.  Assessing alarm against established alarm management protocols and philosophies;
     2.  Designing alarms in compliance with established alarm management protocols and philosophies;

     3.  Developing alarm response documents that detail alarm rationale, response actions, and other
     relevant information for effective operator intervention.

Alarm rationalization should reduce the number of nuisance alarms and afford effective operator response to legitimate critical alarms. This credit trickles down into a facility’s risk profile by impacting process hazard analyses with respect to human response. It is possible to afford Independent Protection Layer (IPL) credit for operator response to an alarm, if an alarm rationalization effort has been conducted. IPL credit for a human often translates into reduced operating, maintenance, and process safety costs by not requiring a Safety Integrated Function (SIF) that needs to be inspected, tested, and periodically repaired or replaced.

Cognascents engineers and facilitators can lead and work with a team of facility personnel to scope and execute an alarm rationalization project. Team members normally consist of process engineers, operators, control engineers, process safety representatives, and maintenance and reliability representatives.

The scope of an alarm rationalization project may include the following tasks:
  • Development of alarm philosophy document
  • Benchmarking of actual alarm system performance
  • Selection and implementation of alarm rationalization software
  • Assessment of alarms by piece of equipment or system of equipment against alarm philosophy and PHAs to determine management requirements
  • Verification of alarm information (e.g. tag, setpoints, audible type)
  • Determination of alarm priority based on alarm philosophy and response time and consequence of inaction
  • Documentation of alarm rationale and other relevant information, such as response actions, possible cause of alarm, differences across batch recipes or other abnormal modes of operation (shutdown and temporary maintenance), and corrective actions
  • Modification of alarm design and attributes based on rationalization exercise (e.g. changing limits, hysteresis, off/on delays, and conditional alarming setpoints)
  • Updating of Process Hazard Analyses (PHAs) as appropriate
  • Development of MoC process for alarms

The following process safety information is typically required to facilitate an alarm rationalization effort:

     1.  Process and Instrumentation Diagrams (P&IDs)
     2.  Cause-and-effect diagrams
     3.  PHAs
     4.  Safe upper and lower Operating Limits (SOLs) with Process Safety Times (PSTs)
     5.  Standard Operating Procedures (SOPs)
     6.  Alarm List

Contact Cognascents to help you scope out and price your next alarm rationalization project. We are here to serve.