A Priority-based Failure Mode and Effects Analysis (FMEA) Method for Risk Assessment of Hydrogen Applications Onboard Maritime Vessels

The maritime industry is gaining momentum towards a more decarbonized and sustainable path. However, most of the worldwide fleet still relies on fossil fuels for power, producing harmful environmental emissions. Hydrogen, as a clean fuel, is a promising alternative, but its unique properties pose significant safety challenges. For instance, hydrogen has a wide flammability range, inherently increasing the risk of ignition. Moreover, its comparatively low volumetric energy density necessitates faster filling rates and larger volumes for bunkering and onboard storage, leading to higher risk rates. Therefore, the use of hydrogen for maritime applications requires the development of specialized riskbased approaches according to safety engineering principles and techniques. The key safety implications are discussed and reviewed with focus on onboard hydrogen storage, handling, and refueling, while a priority-based Failure Mode and Effects Analysis (FMEA) method for risk assessment is proposed based on the revised guidelines of Automotive Industry Action Group (AIAG) and German Association of the Automotive Industry (VDA). The revised AIAG-VDA FMEA method replaces the conventional Risk Priority Number (RPN) with a new Action Priority (AP) rating, enabling the prioritization of recommended actions for risk reduction. The paper aims to a more profound understanding of the safety risks associated with hydrogen as a maritime fuel and to provide an effective risk assessment method for hydrogen applications onboard maritime vessels.