Domain ontology for scenario-based hazard evaluation

•A Scenario Object Model (SOM) is proposed, according to design criteria for ontology.•SOM is used to express multidimensional information of hazard evaluation.•The graphical SOM is constructed throughout the whole process of hazard analysis.•Process hazard information in SOM can be transferred, inherited, and shared.•Computer-aided HAZOP software called CAH is developed based on SOM.

Among the scenario-based hazard evaluation procedures, Hazard and Operability Analysis (HAZOP) is a structured and systematic technique for process hazard examination and risk management widely used around the world. Information used and produced during HAZOP studies is recorded in the form of textual natural language documents. Consequently, reusing this knowledge is limited by the difficulties in finding, retrieving, auditing, sharing, and analyzing HAZOP-related information. Other limitations are faced in terms of computer-based extraction and reasoning of knowledge. To resolve such issues, a domain ontology called Scenario Object Model (SOM) is proposed in this paper, which can be used to represent the contents and structures of hazard evaluation information. Automatic reasoning and semi-quantitative algorithms can be implemented on SOM. Computer-aided automatic hazard evaluation and transferring, auditing, and sharing of HAZOP information have been realized effectively through the use of SOM.