Tehran University of Medical Sciences International Journal of Occupational Hygiene 2008-5109 10 2 2018 05 24 108 113 EN HEMN ZAREI M.Sc. Student, Department of Occupational Health Engineering, School of Health, Jundishapur University of Medical Sciences, Ahvaz, Iran OMID KALATPOUR Center of Excellence for Occupational Health, Research Center for Health Science, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran 2017 12 19 2018 07 21 Due to the high potential consequences of pipeline accidents, it is necessary to manage the inherited risks in the pipeline sectors. Several techniques are available to identify hazardous situations; however, it is crucial that the selected tool is tailored to the scope of work. HAZOP study is one of the most accepted techniques adopted by experts to identify hazards. Despite the wide application of HAZOP in process industries, this method is not suitable for pipelines. In this study, a new extension of HAZOP (P-HAZOP) was introduced through integrating the classic HAZOP and Kent’s method. This research focused on detecting a new sort of deviation from the design intent in pipelines. A previously conducted HAZOP study for a pipeline network was re-conducted using P-HAZOP. A large number of newly detected deviations demonstrated more coverage of the P-HAZOP for the pipeline scope. Finally, it is recommended to improve the traditional HAZOP for pipeline applications. https://ijoh.tums.ac.ir/index.php/ijoh/article/view/324