Tehran University of Medical Sciences International Journal of Occupational Hygiene 2008-5109 4 2 2015 10 11 17 20 EN IRAJ MOHAMMADFAM Department of Occupational Health and Safety, Faculty of Health, University of Hamadan Medical Science, Hamadan, Iran. AMENE SAJEDI Department of Environmental Management, Graduate School of the Environment and Energy, Science and Research Campus, IAU, Tehran, Iran. SHAHRAM MAHMOUDI HSE Department of MAPNA Group, Tehran, Iran. FARHAD MOHAMMADFAM Department of Management, Islamic Azad University of Bonab, Bonab, Iran. 2015 10 10 2015 10 10 Risk assessment and management techniques are used in industrial activities to reduce accidents by applying preventive and protective methods. In this article a preventive approach called Hazard and Operability Study (HAZOP) was used. The application of HAZOP, a process hazard identification and control method, has been demonstrated in the fatty acid unit of Golnar Oil Company, northwest of Tehran Province. The results of the study identifies 58 types of hazard of which 45.6% were unacceptable, 27.1% were unsafe, 18.6% were acceptable but needed reconsideration, 8.7% were acceptable with no need for any corrective action. To prevent any catastrophic consequences, we recommend: (1) installing pressure switch and flow switch on the product-receiving lines, and (2) conducting regular and periodic HSE audit. https://ijoh.tums.ac.ir/index.php/ijoh/article/view/52 https://ijoh.tums.ac.ir/index.php/ijoh/article/download/52/52