Application of a Standardized Plant Analysis Risk-human Reliability Method to Pipeline Inspection Gauge Operations

Abstract

Background and Objective: Pipeline inspection gauge operation which is called “pigging operation” is a practical online monitoring method for maintaining the pipeline in a healthy and safe condition. This operation requires high man-machine interactions. Therefore, it is sensitive to human error which can lead to catastrophic consequences, including human mortality. Materials and Methods: This descriptive study was carried out to assess the probability of human error in pigging operation in a gas transmission plant in Iran. Initially, hierarchical task analysis was conducted via walking through the pigging operation, observing the pigging operation tasks, and doing interviews with operators working in the operation. Subsequently, the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) was utilized to assess the human error probability. Results: In this study, SPAR-H method was implemented on “pigging operation”. The mean value of human error probability (HEP) was estimated at 0.218. It should be noted that the mean value of HEP was regarded as a subtask of “opening bypass valve for decreasing pressure”, as well as a subtask with the highest probability of human error (0.841). Conclusion: The SPAR-H method is a useful tool for practitioners to assess HEP. According to the obtained results, some of the preventive actions to reduce HEP include the utilization of more clarified instructions for performing operations as well as the automation of the launching and receiving pigging cups.

Keywords

• : human error; pigging operation; pipeline inspection gauges; standardized plant analysis risk-human method