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.
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 (above). Barrier types there include the well-control program, mud checks, fill-ups, and escalation barriers....
Operational Risk: Stepping Beyond Bow Ties
01 August 2016