Review and comparison of different risk assessment methods used for intelligent pigging operations in oil and gas pipelines with emphasis on the Bow Tie method

Document Type : Review Article


Department of Environment and HSE, Faculty of Agriculture and Natural Resources, Islamic Azad university, Ahvaz, Iran


Considering the importance and role of process industries, including the oil and gas industry, in each country's economy and on the other hand, as the dangers and risks in these industries are high, it is very important to identify, control and analyze them in process industries. This study aims to investigate and compare different risk assessment methods used for intelligent pigging operations in oil and gas pipelines, emphasising the Bow Tie method. Various risk assessment methods were also examined in this study. Finally, it was observed that the Bow Tie method is an efficient method for assessing the risk of intelligent pigging operation in oil and gas pipelines, which has more advantages than other risk assessment methods, and by combining fault tree analysis (FTA) and event tree analysis (ETA), a comprehensive risk assessment of intelligent pigging operation in oil and gas pipelines can be reached.


Main Subjects

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