Integrated explosion risk assessment for the workplace in a process plant

The improvement of health, safety and protection of workers at risk from explosive in the workplace is governed by the European ATEX Directives requiring the employer to carry out a risk assessment for possible explosion scenario. In order to determine explosion risk, the recently proposed methodology ExLOPA requires the identification of the explosion scenario and its structural elements, conventionally by applying different Process Hazard Analysis methods. This paper presents a novel strategy based on the combination of an expert system for explosion scenario identification (ExSys), with subsequent application of ExLOPA method. An expert system (ExSys) employs values from ad-hoc prepared engineering databases to identify the explosion loss event tailored for the selected target process and the given workplace. Subsequently, an explosion barrier model is developed, to provide data for a representative explosion scenario, which is finally used for explosion risk assessment by the ExLOPA methodology. The proposed technique supports and extends the application of the Layer of Protection Analysis especially for safety assurance assessment of risk-based determination for chemical, petrochemical, pharmaceutical, energy, food, wood and other process industries and related services.