Overview of Measurement and Metrics

Identifying and using relevant process safety metrics over the life of a process is one of four elements in the RBPS pillar of learning from experience.  

What Is It?

The  metrics element establishes performance and efficiency indicators to monitor the near-real-time effectiveness of the RBPS management system and its constituent elements and work activities.  This element addresses which indicators to consider,  how often to collect data, and what to do with the information to help ensure responsive, effective RBPS management system operation. A combination of leading and lagging indicators is often the best way to provide a complete picture of process safety effectiveness.  Outcome oriented lagging indicators, such as incident rates, are generally not sensitive enough to be useful for continuous improvement of process safety management systems because incidents occur too infrequently.  Measuring process safety management performance requires the use of leading indicators, such as rate of improperly performed line breaking activities.

Why Is It Important?

Fortunately, serious process safety accidents occur relatively infrequently.  However, when they do occur, they usually involve a confluence of root causes, some of which involve degraded effectiveness of management systems or, worse, complete failure of management system activities.  Facilities should monitor the real-time performance of management system activities rather than wait for accidents to happen or for infrequent audits to identify latent management system failures.  Such performance monitoring allows problems to be identified and corrective actions to be taken before a serious incident occurs. 

Where/When Is It Done?

One or more metrics can be established for each RBPS element, or a few can be created for the entire system. Metrics can address performance issues, efficiency issues, or both (effectiveness) in all operating phases. Once data gathering/refreshing systems are in place,  metrics can be viewed anywhere, although proposed corrective actions generally occur at the subject facility.  The frequency for refreshing the individual metrics may range from daily, to weekly, to monthly or longer, depending upon the dynamic nature of the metrics, the anticipated costs of data collection, and the local needs. Higher risk situations usually dictate a greater need for formality and thoroughness in scope and level of detail, for example, a larger number of sensitive metrics.  Situations requiring a smaller number of more global metrics covering a smaller scope of the RBPS activities may be adequate for lower risk processes.

Facilities whose operations are very dynamic may result in safety management system element metrics that change frequently, resulting in a need to gather and report metric data more frequently.  Facilities with sound process safety cultures can generally rely on taking snapshots of metrics at less frequent intervals and using fewer metrics to gauge the effectiveness of the system activities. Facilities with an evolving or undetermined process safety culture may require more numerous metrics and greater “command and control” management system features to ensure good performance.

Who Does It?

Metrics data are usually collected by personnel involved in the operation of the RBPS management system element work activities.  Users of the metrics can range from those personnel, to element owners, to facility or corporate management.

What Is the Anticipated Work Product?

The output of this activity is a set of metrics that are sensitive enough to help facility management monitor the performance and efficiency of the RBPS management system on a near-real-time basis.  Metrics may be placed into a scorecard format and provided to various members of facility and corporate management for routine monitoring, or issued in a bulletin format when there are significant or abrupt changes in performance. Outputs of the metrics element can also be used to facilitate the performance of other elements.  For example, metrics that identify dysfunctional RBPS element activities can help target auditing activities.  The ultimate product is using metrics to (1) identify evolving management system weaknesses and (2) make adjustments to RBPS element work activities before the activities degrade into a failed state (performance or efficiency).

How Is It Done?

Metrics can be established as a facility designs, corrects, or improves its process safety management system.  Establishing metrics (and in particular, the data gathering and refreshing mechanisms) is simpler
to do during the initial design and implementation of the system.  Each RBPS chapter in the book has a section that contains a list of possible metrics proposed for that element’s key principles (Section X.5, where X is the chapter number).  Readers can select from these examples or develop their own ideas.  Typically, a small set of metrics is proposed, data are gathered, and the set is pilot tested to see if tracking the metric data helps identify management system degradation.  This metrics experiment should last a minimum of several “metric refresh cycles” and, at most, until the next formal RBPS audit is conducted.  At that time, the audit can show whether the metrics have been correctly projecting the performance of the process safety management system. 

Read more

Chapter 20 of the Guidelines for Risk Based Process Safety describes a process for establishing and maintaining process safety leading indicators (metrics) to aid the near-real-time monitoring of RBPS management system effectiveness and provide input to continuous improvement.  Section 20.2 of the chapter describes the key principles and essential features of a management system for this element.  Section 20.3 lists work activities that support these essential features and presents a range of approaches that might be appropriate for each work activity, depending on perceived risk, resources, and organizational culture.  Sections 20.4 through 20.6 include (1) ideas to improve the effectiveness of management systems and specific programs that support this element, (2) metrics that could be used to monitor this element, and (3) management review issues that may be appropriate for the metrics element.

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