Component Failure Taxonomy and Leak Rate Quantification for Hydrogen System Safety and Reliability

Safety events through failed components at hydrogen facilities increase maintenance costs and risks, cause downtime, and impact public perception. Quantifying the component reliability can guide the design and operation of hydrogen facilities with improved safety and profitability. Uncertainties in both the amount of hydrogen emitted from leaking components and the frequency of those failure events limit the ability to realize safety and profit goals. To better understand component failures and leak rate, we developed a taxonomy to enable anonymized component failure tracking. This is paired with assessing the potential hazards for the released hydrogen by quantifying the leaks through failed components using the NREL Leak Rate Quantification Apparatus (LRQA). The taxonomy for anonymized component failure tracking is a list of 23 requirement for a hydrogen component reliability database. The taxonomy includes component breakdowns for most components included in a hydrogen fueling station and a list of clearly defined failure modes for each system. The LRQA has been used to quantify the leaks of air operated valves, manual valves, thermocouples, and check valves. Leak data then has been input into HyRAM for risk assessment and categorization or grading according to ASME B31.12. of the leak. This work connects well-defined tracking of component failures rates to empirical leak rate quantification. This presentation will illustrate with examples the use of the component identification taxonomy, the strengths and gaps in current component failure data collection, and the potential risk, based on leak size to enable data-driven improvements for hydrogen system safety and reliability.