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DOE OSTI · 2463036

Quantitative Risk Assessment for Hydrogen-Powered Locomotive Refueling

Louie, Melissa Sui-hui·Heo, YeongAe·Ehrhart, Brian David
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Abstract

Hydrogen powered locomotives are being explored to reduce emissions in rail applications. The risks of operations like refueling should be understood to ensure safe environments for workers and members of the public. Sensitivity analyses were conducted using HyRAM+ to identify major drivers of risk and compare effects of system parameters on individual risk. The consequences of jet fires from full-bore leaks dominated the risk, compared to explosions or smaller leaks. Pipe size, leak detection capability, and leak frequencies of system components greatly affected risk while overpressure modeling parameters and ambient conditions had little effect. The effects of personal protective equipment (PPE) materials on individual risk were quantified by reducing the individual’s exposure time or absorbed thermal dose. PPE only showed a risk reduction in low-risk cases. This study highlighted target areas for risk mitigation, including leak detection equipment and component maintenance, and indicated that the minimal effects of other parameters on risk may not justify prescriptive requirements for refueling operators.

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Louie, Melissa Sui-hui, Heo, YeongAe, Ehrhart, Brian David. 2024-08-01. Quantitative Risk Assessment for Hydrogen-Powered Locomotive Refueling. https://doi.org/10.2172/2463036

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