Seyed Mahdi Mousavi - Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences
Ali Karimi - Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences
Seyed AbolFazl Zakerian - Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences
GholamReza Makvandi - Office of Traffic Safety and Control, Abadan oil Refinery
Mehrdad Mehravar - Department of Health Information Management and Medical Informatics, Faculty of Paramedical Sciences, Tehran University of Medical Sciences

Background: Permit-to-work system is a process used to prevent accidents in the process industries. Evaluation and monitoring of the performance of a permit to work system reveal its inherent weaknesses and reduce accidents in process industries. Since there exists no local tool for monitoring the performance of permit-to-work system in refineries and process industries, such as petrochemicals, the present study aimed to develop and validate a questionnaire assessing the performance and effectiveness of permit-to-work system in an oil refinery located in southern Iran. Methods: Six criteria were identified as the main components of permit-to-work system and the initial questionnaire was designed after reviewing the literature and existing guidelines in permit-to-work system, as well as interviewing industry and university experts familiar with permit-to-work system. The criteria included risk assessment, risk prevention and control, coordination and information, sense   of responsibility, Clarity and transparency, and documentation.The face validity and content validity of the questionnaire were evaluated based on the viewpoints of 25 industrial and academic experts using Lawshechr('39')s method. Cronbachchr('39')s alpha test was rendered using SPSS software(version 25) based on 100 referred questionnaires out of a total of 120 questionnaires distributed among operational staff (site staff, senior staff, control room staff), security officers, and shift officers who were in charge of issuing or approving work permits in the refinery. Results: The initial questionnaire consisted of 65 questions out of which 50 questions were selected after the assessment of face and content validity of the questionnaire and 15 questions with CVR <0.37 and CVI <0.79 were removed and Cronbachchr('39')s alpha for the whole questionnaire was measured at 0.81. Conclusion: Assessment of the validity and reliability of the questionnaire revealed that the designed questionnaire has appropriate validity and reliability to evaluate the performance and efficacy of permit-to-work system. Accordingly, this questionnaire can be used as an efficient instrument to evaluate the performance of  permit-to-work system in process industries, such as oil refineries and petrochemicals.

Permit-to-work system, Performance evaluation, Validation, Oil refinery