Predicting major hazard accidents in the process industry based on organizational factors: A practical, qualitative approach

Abstract

OCI Nitrogen seeks to gain knowledge of (leading) indicators regarding the process safety performance of their ammonia production process. The current sub-study raises the question whether major hazard accidents in the ammonia production process can be predicted from organizational factors, also called management delivery systems. This paper links organizational factors to accident processes and their barrier systems, using the bowtie metaphor. It is shown that organizational factors indirectly impact accident processes as they strongly influence the quality or trustworthiness of the barrier systems. By putting the right focus on organizational factors during audits or reviews, major accident processes get the attention they deserve, and the necessary actions are taken at the right management level. Qualitative and quantitative monitoring of organizational factors can provide a picture of their operation and efficiency. Using an example on retrospective data it is demonstrated that information from organizational factors could have stopped the development of the near-accident prematurely. However, organizational factors should first be qualitatively assessed before they are quantitatively monitored. A quantitative assessment has been worked out for one of the management delivery systems so to provide an example of management indicators. Determining these (management) indicators from threshold values is an intricate matter due to the complicated influence of organizational factors on accident processes, and requires more follow-up research.