Operational Risk: Stepping Beyond Bow Ties

Abstract

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 174995, “Operational Risk: Stepping Beyond Bow Ties,” by D. Fraser, SPE, J. Braun, and M. Cunningham, Argonne National Laboratory; B. Marple, Chevron; D.D. Moore, SPE, Marathon; A. Sas-Jaworsky, SPE, SAS Industries; and J. Wilson, Transocean, prepared for the 2015 SPE Annual Technical Conference and Exhibition, Houston, 28–30 September. The paper has not been peer reviewed. This paper presents the multiple-physical- barrier (MPB) approach to operational (or process) risk, an extension of the common bow-tie technique for identifying risk. Bow ties identify a variety of different types of barriers and help communicate safety principles that link causal factors and subsequent actions to a specific event. By narrowing the focus to physical barriers and by developing success paths that enable each barrier to perform its safety function, the MPB approach moves further toward a systematic approach to operational-risk management. Introduction—Operational Risk, Bow Ties, and Physical Barriers Operational Risk. One of the more elusive issues in the upstream oil and gas industry is the understanding of process safety or process risk—especially how it overlaps with industrial (or personal) safety—and the types of tools needed to assess and manage it. An important part of this hinges on the role that barriers play in the analysis and what constitutes a barrier. Some companies consider training to be a barrier, others consider certain meetings to be barriers, and still others consider safety procedures themselves to be barriers. Indeed, there is scarce practical agreement between companies as to how process risk is assessed, managed, and communicated. As a result, there can be similarities, but, ultimately, no two process-risk assessments from different companies look the same. Several different barriers are shown in the bow-tie diagram in Fig. 1. Barrier types there include the well-control program, mud checks, fill-ups, and escalation barriers. Bow-Tie Analysis. Bow-tie analysis has been widely used in the offshore oil and gas industry as a technique for communicating safety issues and safety control measures. Bow-tie analysis is event based; it seeks to tie causal factors and subsequent actions to a specific event, such as a kick. Bow-tie diagrams help teams better understand the sequences that can lead to serious process or operational risks. They also identify mitigating actions that can be taken to reduce the consequences of a major event. The MPB Approach—A Pathway to Success The MPB approach was developed with the help of collaborations from the upstream oil and gas industry. It takes a step beyond bow ties toward a more-direct and -systematic understanding of operational risk so that operators can design their operations to be successful. In so doing, risk is systematically identified and evaluated and can be incorporated into the management system to help ensure the safety of offshore operations.