Real-World Application of the Bow-Tie Method

Abstract

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 154549, ’Lessons Learned From Real-World Application of the Bow-Tie Method,’ by Gareth Book, Risktec Solutions, prepared for the 2012 SPE Middle East Health, Safety, Security, and Environment Conference and Exhibition, Abu Dhabi, 2-4 April. The paper has not been peer reviewed. Also known as barrier diagrams, bow-tie diagrams provide an understandable visualization of relationships between the causes of business upsets, the escalation of such events to a range of possible outcomes, the controls preventing the event from occurring, and the preparedness measures in place to limit consequences. Preventive and mitigating measures are linked to tasks, procedures, responsible individuals, and competencies. This crucial connection between risk controls (whether hardware or human intervention) and the management system ensures ongoing effectiveness. Introduction The primary motivation for the use of bow-tie diagrams was to seek assurance that fit-for-purpose risk controls were consistently in place throughout all operations worldwide. Their use has spread between companies, industries, and countries and from industry to regulators. This paper aims to demonstrate the practical uses and benefits of this versatile tool, which can be used to qualitatively assess and to demonstrate control of all types of risk in many industries and business sectors. The complete paper details an example case. Bow-Tie Method The bow-tie method shown in Fig. 1 provides a readily understood visualization of the relationships between the causes of business upsets, the escalation of such events, the controls preventing the event from occurring, and preparedness measures to limit the business effects. In its most common use, the ultimate aim is to demonstrate control of health, safety, and environmental (HSE) hazards; therefore, it is first necessary to identify those hazards requiring bow-tie analysis. Once hazards have been identified, the bow-tie method can be applied to assess risks further and provide a framework for demonstrating effective control. Typically, bow ties are developed by asking a structured set of questions that build the diagram in a step-by-step fashion, detailed in Figs. 2 through 4 in the complete paper. Applying the Technique. Development of the bow-tie diagrams and critical tasks should be carried out in a structured manner to obtain quality information and best represent the actual risk-control arrangements. Fig. 2 summarizes an effective building process, which has been developed and refined through experience with a variety of companies, industries, and work groups.