Event
- Event ID
- 203
- Quality
- Description
The pressure building valve opened due to vibration from the road, causing the build-up of the internal pressure. The drivers performed a hydrogen venting and re-sealed the valve.
- Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- release, no ignition
- Macro-region
- North America
- Country
- United States
- Date
- Component involved
- valve (pressure building)
- Failure mode
- leak
- Initiating cause
- over-pressurisation
- Root CAUSE analysis
The INITIATING CAUSE was the loosening of a valve use to pressurise the tanker, due to road vibration. The ROOT CAUSE could be attributed to a shortcoming in the design of the connections or to the failing to tighten correctly the valve.
- Root causes
- Date entry in HIAD
- 20/01/2025
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- H2 delivery to customers
- Hydrogen supply chain stage
- All components affected
LH2 road tanker
- 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 and re-sealing of the valve
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%
- 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)
