An ontological approach to identify the causes of hazards for safety-critical systems

Preliminary hazard analysis (PHA) is a key safety-concerned technique, applied in early stages of safety critical systems development, aiming to provide stakeholders with a general understanding of potential hazards together with their causes. Various studies have asserted that most significant flaws in hazard analysis techniques are related to the omission of causes associated with the identified hazards. In addition, identified causes are sometimes described in too generic terms to provide useful guidance for subsequent activities. In this paper, we propose an approach to explore and identify the causes associated with the hazards from a PHA, aiming to improve the results of hazard causes identification in terms of completeness and usefulness. To achieve the goal, the proposed approach utilizes the hazard-related concepts and relations defined in a hazard domain ontology presented in our previous work [1]. Furthermore, an application scenario of a train control system is used to evaluate our approach.