Safety Critical Task Analysis (SCTA): Identifying & Reducing Opportunities for Human Error

Abstract

Abstract It is commonly known that human errors whilst undertaking safety critical tasks (SCTs) has been a significant contributory factor in a number of major incidents in the O&G industry (e.g. Deepwater Horizon, Texas City, Piper Alpha, etc). This paper will discuss the Safety Critical Task Analysis (SCTA) methodology as a way to proactively identify and review the human factors affecting safe and effective completion of SCTs. The methodology involves determining which tasks are safety critical, developing a priority listing of SCTs for analysis, applying guidewords to establish which human action could contribute to an incident (or make a barrier less effective or fail), identifying the performance influencing factors (PIFs) that contribute to the potential for a human to make an error/mistake, and establishing mitigation measures to reduce the likelihood or consequence of human error. The paper will discuss how the approach will vary depending on the application scenario, for example during Projects (i.e. FEED and Detailed Design), or during facility operations. SCTA is focused on tasks that have the potential to lead to major accident hazards (MAHs) not occupational risks. SCTA provides a structured approach for assessing the whole working environment and the socio-technical system, and provides an enhanced awareness of the individual safety critical steps in a SCT. The paper will discuss how existing safety reports (e.g. bowtie analysis) can be used to identify the focus for the SCTA in support of the barrier management process, and the range of human influencing shaping factors (PIFs) that contribute to the occurrence of human error (i.e. Job Factors, Person Factors and Organisational Factors). The paper will describe the adaptations made to the methodology depending upon the focus of the SCTA (i.e. during Projects, input to safety case/reports, or when changes occur to SCTs on-site), and how SCTA is becoming embedded as an ongoing facility activity, building STCA capability and awareness into frontline operations as part of the overall safety management system (SMS).