Sequentially Timed Events Plotting (STEP) method: investigating the hydrocarbon loading station explosion

This chapter examines the Sequentially Timed Events Plotting (STEP) Methodology in Accident Analysis, offering an exploration of its development, application, advantages, and limitations. Originating in 1987 as a response to shortcomings in traditional accident investigation methods, STEP stands out for its emphasis on temporal aspects and multi-linearity in incident modeling. The chapter systematically guides readers through the intricacies of STEP, detailing its key components such as actors, events, and safety problems, presented in a chronological framework. A notable feature is the STEP worksheet, providing a visual representation that aids in the reconstruction of actions leading to undesired events. Practical considerations are infused into each step of the methodology, transforming STEP into a holistic tool for organizational improvement. A realistic incident analyses illustrated the methodology’s effectiveness in uncovering contributing factors and safety challenges. The chapter concludes by highlighting the primary advantages and disadvantages of STEP, acknowledging its strengths in providing chronological sequences and agent-centric analyses, while also recognizing challenges related to complexity, data dependency, and subjectivity. Understanding these facets is essential for a nuanced application of STEP, ensuring its alignment with the nature and scope of incidents under investigation.