Event
- Event ID
- 193
- Quality
- Description
- The vent valve on a liquid hydrogen tanker vibrated open allowing a slight discharge hydrogen.
[Zalosh and Short, 1978] - Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- Leak No Ignition (No additional details provided)
- Macro-region
- North America
- Country
- United States
- Date
- Main component involved?
- Valve (Generic)
- How was it involved?
- Leak & Formation Of A Flammable H2-Air Mixture
- Initiating cause
- Loss Of Tightness (Road Vibrations)
- Root causes
- Root CAUSE analysis
- The INITIATING CAUSE was the loosening of the vent valve due to vibration while travelling.
The ROOT CAUSE could be attributed to a shortcoming in the design of the valve connection, or the failing to tighten correctly the valve.
Facility
- Application
- Hydrogen Transport And Distribution
- Sub-application
- LH2 tanker
- Hydrogen supply chain stage
- Hydrogen Transport (No additional details provided)
- All components affected
- vent valve
- Location type
- Open
- Operational condition
Emergency & Consequences
- Number of injured persons
- 0
- Number of fatalities
- 0
- Currency
- US$
- Property loss (onsite)
- 0
- Property loss (offsite)
- 0
- Emergency action
- The emergency state of the plant is called few minutes from the burst. The system is made safe by stopping the hydrogen supply and filling the reactor with nitrogen.
The valves of the rain water network are closed to confine the water contaminated by the liquids released. This waste is burned in the evaporator of the plant. The emergency is called off half hour after the event.
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."
Event Nature
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Presumed ignition source
- No ignition
References
- Reference & weblink
Extract from Table III of Appendix A of Zalosh and Short<br />
COMPARATIVE ANALYSIS OF HYDROGEN FIRE AND EXPLOSION INCIDENTS<br />
Quarterly Report No. 2 for Period December 1, 1977 - February 28, 1978<br />
https://www.osti.gov/biblio/6566131<br />
(accessed September 2020)
JRC assessment
- Sources categories
- Zalosh
