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.