Multi‐Criteria Decision‐Making Methodologies Applied to Hazard and Operability Studies in High‐Hazard Industries

ABSTRACT Major accidents causing fatalities and significant environmental and asset damage continue to occur in high‐hazard industries, despite regulatory requirements and organisational mitigation measures. The Hazard and Operability (HAZOP) study is a widely used risk assessment method to identify hazards and implement mitigation measures, but it has limitations, including the effort required and challenges in prioritising recommendations. This study reviews the integration of Multi‐Criteria Decision Making (MCDM) methodologies with HAZOP in high‐hazard industries. A case study using Analytical Hierarchy Process (AHP), Preference Ranking Organisation Method for Enrichment Evaluation (PROMETHEE) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) demonstrated varying results based on effort, time and outcome verification. The results informed a guide that selects the most suitable MCDM method based on the number of recommendations, residual risk ranking and degree of separation. This paper demonstrates that MCDM methodologies can enhance HAZOP studies by improving recommendation prioritisation in high‐hazard industries.