A new risk evaluation method for oil storage tank zones based on the theory of two types of hazards

Abstract Oil storage tank zones possessing large amounts of harmful substances and energy with great probability of accidental release, can pose risks to personnel, equipment facilities and environment. With risks becoming more complex and diverse, risk evaluation approaches are required to quickly identify hazards, effectively assess safety performances. This paper presents a new risk evaluation model for oil storage tank zones based on the theory of two types of hazards. Firstly, the two types of hazards (inherent hazards, controllable hazards) in oil tank zones are identified, analyzed and classified. Secondly, inherent hazards of oil storage tank zones are quantitatively evaluated by the major hazards method (flammable, explosive and toxic), which conducted on the possibility and severity of accidents. Thirdly, (i) using Fault Tree Analysis (FTA), the risk factors that can lead to the emergence of controllable hazards are identified. These risk factors are screened by structural importance degree to next analysis step as the evaluation factors. (ii) The Analytic Hierarchy Process (AHP) is applied to determine the weight of each index. (iii) After the construction of the multi-factor fuzzy evaluation matrix, fuzzy comprehensive evaluation mode for controllable hazards is established. Finally, the comprehensive risk rank of oil storage tank zones, constituted by the coupling effect of inherent hazards and controllable hazards, is assessed by the developed risk matrix, which provides related standards for risk classification. The proposed method is validated to be more practicality and orderliness by the example.