ABSTRACT
Dynamic Positioning (DP) control system is currently utilized for maintaining the position of Floating Production Storage and Offloading (FPSO) in a variety of the ocean environment conditions. However, FPSO in the Arctic region, which operates under diverse ice conditions, should be designed with an advanced mooring system together with the DP system as the FPSO needs safer system compared with the normal DP systems. A novel DP and mooring system for the FPSO operating in the Arctic region is now being developed at KRISO in Korea. A platform shape of the FPSO that has minimum resistance and maximum operation efficiency is also under development. Therefore, analyses and assessments of potential risks are required, considering that the developing system has many novelties compared to the conventional DP or mooring system. Hazard identification study (HAZID) is one of the most widely used traditional methods to identify hazards of a system, and the method is simple to use and requires limited training. System Theoretic Process Analysis (STPA), on the other hand, was recently developed for modern complex control systems and provides systematic analysis procedure based on systems theory. The main objectives of this study are to suggest an approach for hazards identification associated with the design and operation of DP and mooring system, by utilizing complementary hazard identification methods (HAZID and STPA). HAZID has been applied to the structural part of the system, while STPA has been applied to the control system. The paper also includes a comparison of the strengths and weaknesses of the selected methods and a discussion of complementary use of HAZID and STPA.
