Event
- Event ID
- 149
- Quality
- Description
Excessive delay in trip resulted in over-pressure on the liquid hydrogen tank, requiring manual venting. This resulted in releasing of 2750 cu ft of hydrogen (approximately 7 kg).
- Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- Macro-region
- North America
- Country
- United States
- Date
- Component involved
- LH2 tank (road tanker)
- Failure mode
- manual venting
- Initiating cause
- over-pressurisation (excessive boil-off)
- Root CAUSE analysis
The INITIATING CAUSE was a delay during the delivery journey. The reason for the delay is not provided.
The preventing measure (manual venting to reduce overpressure) functioned as planned.- Root causes
- Date entry in HIAD
- 20/01/2025
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- LH2 tanker
- Hydrogen supply chain stage
- All components affected
manual vent
- Process temperature range [C]
- cryogenic temperature (below -50°C)
- Process pressure range [MPa]
- low to medium pressure (below 2 MPa)
- Location type
- Open
- Location
- highway or similar
- Operational condition
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Currency
- US$
- Property loss (onsite)
- 0
- Emergency action
manual venting
Lesson Learnt
- Lesson Learnt
Zalosh et al (see references), concluded their analysis of hydrogen transportation accidents till 1978 with the following conclusions:
"Finally, an encouraging aspect of the transportation incident compilation is that 71% of the hydrogen releases did not lead to an ignition. ... The relatively few ignitions may be due to either to lack of ignition sources or to the rapid dispersal of hydrogen into the atmosphere. In any event, the accident data provide further incentive t o transport , transfer and store hydrogen outdoors away from occupied areas."
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Released amount (kg)
- 6.529655
- Probable IGNITION SOURCE
References
- Sources categories
- Zalosh
- Reference & weblink
Extract from Table III of Appendix A of Zalosh and Short
COMPARATIVE ANALYSIS OF HYDROGEN FIRE AND EXPLOSION INCIDENTS
Quarterly Report No. 2 for Period December 1, 1977 - February 28, 1978
https://www.osti.gov/biblio/6566131
(accessed September 2020)Event no. I-1974010179 of the US Pipeline and Hazardous Materials Safety Administration PHMSA:
https://www.phmsa.dot.gov/data-and-statistics/pipeline/distribution-tra…
(accessed September 2024)
