Use of procedures is an integral part of operating a large industrial process to achieve consistent, safe production. Industry regulations, e.g., OSHA 1910, require companies to provide written operating procedures that contain clear instructions for safely executing activities for startup and shutdown as well as normal, temporary and emergency operations. This article discusses some key challenges with procedural operations identified in an analysis of major industry incident reports by the Abnormal Situation Management (ASM) Consortium, www.asmconsortium.org, and recommended practices to mitigate the associated risks.

In the context of this article, the term "procedure" refers to a written document containing step-by-step work instructions to complete a single objective such as starting up a process unit. The common business drivers for use of procedures are to avoid safety and environment incidents, establish efficient and effective operations, and supplement employee knowledge and experience.

The ASM Consortium defines an abnormal situation as an event disturbing a process that requires the operations team to intervene to supplement the control system. This definition specifically is used to distinguish among normal, abnormal and emergency situations from the perspective of console operations. The objective of abnormal situation management is to return the process to normal before safety systems are engaged.

The consortium's focus on the use of procedures has been to examine whether enhancements to the procedure management system might enable operators to more effectively prevent or respond to abnormal situations.

PROCEDURE EXECUTION FAILURES
To better understand how to improve use of procedures, the ASM Consortium conducted a study to investigate procedure execution failure modes associated with abnormal situations [1]. A team examined root causes of failures covered in a previous analysis of 32 process industry incident reports. That earlier analysis [2] indicated that ineffective use of procedures significantly contributed to major incidents and represented 8% of all root causes.

The team assessed whether the procedural failure occurred prior to or during an abnormal situation; those arising beforehand were deemed irrelevant to procedure execution during the abnormal situation. The analysis showed that 40 of the 70 identified procedure-related root causes, i.e., 57%, were linked to procedure execution failures in abnormal situations (Table 1).

How these root causes manifest themselves provides better insight into how to make improvements in operations practices than the more generic root cause classifications [2]. Examination of the 40 identified root causes showed the most common manifestation was associated with lack of knowledge about appropriate responses to the occurrence of an abnormal situation while executing a procedure (Table 2) — followed by the failure to detect the presence of an abnormal equipment or process mode while executing a procedure, and the lack of understanding the impact or effect of performing or not performing a procedural action. In total, these three accounted for 87.5% (35 out of 40) of the procedural execution failures under abnormal situations.

Based on this analysis, the study team identified the need for effective procedure content in the following areas to improve operations' performance during abnormal situations:

• Responding appropriately to the occurrence of an abnormal situation in the execution of the procedure;
• Detecting whether equipment or the process are in abnormal mode and whether there are any latent abnormal conditions;
• Spotting excursions from normal operating range and knowing the indications of the occurrence of an abnormal situation; and
• Understanding the correct impact or effect of a procedural action and the repercussions of not following the procedural instruction.

ADDRESSING THE CHALLENGES
The analysis of common root causes and root cause manifestations suggests a need for improvements not only in the content of procedures but also in the procedure management system itself. Based on this analysis and plant experiences, the ASM Consortium member representatives identified three challenges to reduce the risk of procedure execution failure during abnormal situations:

1. Organizational culture that fails to enforce an effective policy on use of procedures. This is a symptom of a failure to establish a policy that's compatible with the pragmatics of the operations work environment. Even if a formal policy is in place, it typically just notes that employees are expected to follow procedures at all times. Often the policy doesn't clearly state whether "following procedures" means personnel may recall the procedure from memory or must have the written procedure in their hands during its execution.

Most plants adopt a pragmatic practice of letting individual operators decide how they will use a procedure document. Any given operator may be expected to know and follow dozens of procedures. The frequency, complexity and potential risks may differ quite significantly among these procedures. However, the typical policy doesn't distinguish between a simple, routine procedure with low risk, such as swapping pumps, versus a complex, non-routine plant startup procedure with high risk. Moreover, left to the discretion of the individual, whether a procedure document is used prior to or during execution can vary substantially.