Risk assessment of hydrogen systems: a review and comparison of frameworks and guidelines from Norwegian regulators

• We conduct a systematic comparison of hydrogen risk assessment frameworks in Norway. • Key similarities and differences between the various frameworks are highlighted. • The paper reveals significant conceptual and methodological differences. • The implications of regulatory fragmentation for hydrogen safety are discussed. • Recommendations for harmonizing hydrogen risk assessment practice are provided. The transition towards hydrogen as a sustainable energy carrier has increased the focus on ensuring its safe implementation across various applications. A key instrument to obtain a satisfactory level of safety is adherence to regulatory frameworks and guidelines. However, the hydrogen industry faces a complex landscape of various frameworks and guidelines from different regulatory bodies. This complexity could result in inconsistent practices for hydrogen safety across sectors, such as maritime, transportation systems and industry. In Norway, this issue is exemplified by the differing frameworks and guidelines set by the Norwegian Ocean Industry Authority (Havtil), the Norwegian Maritime Authority (NMA) and the Norwegian Directorate for Civil Protection (DSB). In this paper, we present a qualitative comparative analysis of existing risk analysis frameworks and guidelines referred to by the aforementioned Norwegian regulatory bodies. The main purpose is to examine the key principles, methodologies and approaches, highlighting potential differences and conflicts in regulatory expectations. The findings reveal significant differences when it comes to how the frameworks define fundamental concepts, integrate human and organizational factors, address uncertainty and knowledge aspects and establish principles for risk evaluation and acceptance. These variations have implications for the coherence and suitability of risk assessment practices for hydrogen systems and activities. The paper concludes with recommendations to enhance the coherence and consistency of safety practices within the hydrogen sector, with the aim of facilitating a safer and more efficient adoption of hydrogen technologies across industries.