The project established a generic hydrogen system definition for rail vehicles as the foundation for a comprehensive risk assessment. Using a two‑stage approach, the initial risk was evaluated without mitigation measures, followed by a final risk assessment that incorporated identified risk‑reducing actions. Hazard identification focused on released hydrogen, mechanical failure, dimensional inadequacy, unsuitable materials, insufficient design, and pressure resistance. For each hazard, the team mapped the root causes and linked them to relevant normative requirements. The resulting risk matrix combined severity, frequency, and exposure categories to quantify residual risk levels. The analysis demonstrated that the proposed mitigation measures—such as pressure‑resistant construction, material qualification, leak detection, and safety‑critical system interfaces—sufficiently reduce the risk to acceptable levels for rail applications.

Normative research was a core component of the work. The team surveyed over 500 entries from standards bodies including SAE, DIN (Beuth), EIGA, and IEC. The IEC 63341‑1 and IEC 63341‑2 documents were identified as the primary reference frameworks for hydrogen systems in rail vehicles, with the latest versions accessed in February 2022. The research process involved filtering standards by relevance to rail‑specific hazards, categorizing them by system and cause, and extracting performance requirements such as pressure endurance, material compatibility, and leak‑detection thresholds. These requirements were incorporated into a guideline draft that serves as a safety‑management tool rather than a national technical regulation. The guideline outlines installation and operational procedures, qualification of components, pressure‑storage testing, and documentation standards, providing a unified assessment framework that can be adapted to project‑specific needs.

The technical deliverables also include a detailed system architecture diagram, interface specifications between the hydrogen propulsion system and the vehicle, and an accident‑event chain model. These artifacts support the validation and verification of hydrogen‑powered rail vehicles, enabling systematic testing of first‑time and recurring inspections. The project’s methodology—bottom‑up hazard identification, risk quantification, and normative mapping—offers a repeatable process for future hydrogen projects in the rail sector.

Collaboration was carried out by a consortium led by TÜV Rheinland InterTraffic, which provided the project structure and risk‑analysis expertise. Other partners contributed through standard‑setting bodies such as EIGA, SAE, DIN, and IEC, ensuring that the guideline aligns with international and European norms. The project’s scope encompassed the entire lifecycle of hydrogen system integration, from design and qualification to testing and documentation. While the report does not specify a funding source, the extensive engagement with European standard bodies and the use of IEC documents suggest alignment with broader EU initiatives on sustainable transport. The timeline of the project is reflected in the reference dates of the IEC standards (accessed in early 2022) and the development of the guideline draft, indicating a multi‑year effort that culminated in a practical safety framework for hydrogen rail vehicles.