Jahangiri Mehdi, Hoboubi Naser, Rostamabadi Akbar, Keshavarzi Sareh, Hosseini Ali Akbar
Research Center for Health Sciences, Department of Occupational Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran.
Student Research Committee, Department of Occupational Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran.
Saf Health Work. 2016 Mar;7(1):6-11. doi: 10.1016/j.shaw.2015.06.002. Epub 2015 Jul 6.
A permit to work (PTW) is a formal written system to control certain types of work which are identified as potentially hazardous. However, human error in PTW processes can lead to an accident.
This cross-sectional, descriptive study was conducted to estimate the probability of human errors in PTW processes in a chemical plant in Iran. In the first stage, through interviewing the personnel and studying the procedure in the plant, the PTW process was analyzed using the hierarchical task analysis technique. In doing so, PTW was considered as a goal and detailed tasks to achieve the goal were analyzed. In the next step, the standardized plant analysis risk-human (SPAR-H) reliability analysis method was applied for estimation of human error probability.
The mean probability of human error in the PTW system was estimated to be 0.11. The highest probability of human error in the PTW process was related to flammable gas testing (50.7%).
The SPAR-H method applied in this study could analyze and quantify the potential human errors and extract the required measures for reducing the error probabilities in PTW system. Some suggestions to reduce the likelihood of errors, especially in the field of modifying the performance shaping factors and dependencies among tasks are provided.
工作许可证（PTW）是一种正式的书面系统，用于控制某些被确定为具有潜在危险的工作类型。然而，PTW流程中的人为错误可能导致事故。
本横断面描述性研究旨在估计伊朗一家化工厂PTW流程中人为错误的概率。在第一阶段，通过与工厂人员进行访谈并研究工厂的程序，使用层次任务分析技术对PTW流程进行分析。在此过程中，将PTW视为一个目标，并对实现该目标的详细任务进行分析。下一步，应用标准化工厂分析风险-人（SPAR-H）可靠性分析方法来估计人为错误概率。
PTW系统中人为错误的平均概率估计为0.11。PTW流程中人为错误概率最高的是可燃气体检测（50.7%）。
本研究中应用的SPAR-H方法可以分析和量化潜在的人为错误，并提取降低PTW系统中错误概率所需的措施。提供了一些降低错误可能性的建议，特别是在修改绩效塑造因素和任务之间的依赖性方面。
