System approach to operational ship safety

  • Stuart Mansfield Williams

Student thesis: Doctoral Thesis


In the late 1980s and early 1990s the International Maritime Organization (IMO) responded to the sinking of the Herald of Free Enterprise and the Scandinavian Star by requiring that ship operators implement safety management systems (SMSs). The requirement for using SMSs became mandatory in 2002 with the adoption of the International Safety Management (ISM) Code by the International Maritime Organization (IMO). While ground-breaking at the time, the regulation has not been significantly updated. The literature review showed that air and rail transportation SMS implementations have been significantly improved to assess hazards more comprehensively and to require safety indicators to measure the performance of the SMS. The aim of this research is to fill the gap in the use of safety indicators in the maritime domain by providing a set of safety indicators to provide ship operator with better feedback on the state of their safety management approaches. This dissertation develops a new extension of the System Theoretic Process Analysis (STPA) to model the safety management systems at two ship operators to assess and track the hazards within each company's SMS. The STPA is extended to create safety system indicators following a revised SMS template that contains four foundational pillars: safety policy and objectives, safety risk management, safety assurance and safety promotion. Prioritization of the indicators generated in each area yields a set of key safety indicators. New indicators for repeat audit findings, quality of hazard analysis and additional indicators to track risk management performance are recommended for ship operators. Combining common results from the modelling at both companies an initial set of generic key safety indicators applicable to any ship management company was created.
Date of Award25 Nov 2020
Original languageEnglish
Awarding Institution
  • University Of Strathclyde
SupervisorDracos Vassalos (Supervisor)

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