en Occupational and Industrial Health Occupational and Industrial Health پژوهشي Original Article <p><span style="font-size:14px;"><span style="font-family: times new roman;"><strong>Background;</strong> Prevention of accidents&mdash;a crucial requirement in oil industries&mdash;involves hazard recognition, risk assessment, and corrective actions. The purpose of this study was to compare the ETBA and HAZOP techniques for risk assessment in a gasoline refinery unit.<br> <strong>Methods;</strong> In this case study, data were collected using process flow diagram, walking&ndash;talking through method, piping and instrumentation diagram, and direct observations. Worksheets for both techniques were filled on the basis of the risk assessment matrix MIL-STD-882E.<br> <strong>Results;</strong> The HAZOP method identified 44 deviations attributable to 118 causes. In addition, 11.37% of the identified hazards were associated with unacceptable risk, and 36.36%, with unfavorable risk. The ETBA method detected 10 groups of energy (24 subgroups); 33 hazards were detected, 10.62% of which were associated with unacceptable risk.<br> <strong>Conclusion;</strong> HAZOP proved to be the more powerful technique for the prediction and identification of hazards. However, ETBA detected certain hazards that were not identifiable using HAZOP. Therefore, a combination of these two methods is desirable for the assessment of hazard risk in process industries.</span></span></p> Oil Refinery, Hazard, ETBA, HAZOP 19 27 http://jhehp.zums.ac.ir/browse.php?a_code=A-10-28-1&slc_lang=en&sid=1 Sedigheh Abbasi arghami@zums.ac.ir 10031947532846009276 10031947532846009276 No Department of Occupational Health, Zanjan University of Medical Sciences, Zanjan, Iran. Shakiba Bakhtom Sh.bakhtom@gmail.com 10031947532846009277 10031947532846009277 No Department of Occupational Health, Zanjan University of Medical Sciences, Zanjan, Iran. Mansour Ziaei Ziaei@kums.ac.ir 10031947532846009278 10031947532846009278 No Department of Occupational Health, Kermanshah University of Medical Sciences, Kermanshah, Iran. Shirazeh Arghami arghami@zums.ac.ir 10031947532846009279 10031947532846009279 Yes Department of Occupational Health, Zanjan University of Medical Sciences, Zanjan, Iran.