Event
- Event ID
- 320
- Quality
- Description
- This event occurred at after the testing of a LH2 tank. The LH2 was then removed and the tank purged with helium gas for more than 4 hours. A flange was then removed to allow for insertion of smaller tank, at which time an explosion occurred.
[Ordin, NASA (1974)] - Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- Macro-region
- North America
- Country
- United States
- Date
- -
- Main component involved?
- Cryogenic Vessel
- How was it involved?
- Internal Explosion (H2-Air Mixture)
- Root causes
- Root CAUSE analysis
- The INITATING CAUSE was the formation and ignition of an air-hydrogen explosive mixture in the tank.
Hydrogen gas was still present after the 4.5 hours of purging, when a second tank was inserted. The outer tank was still cold and air could enter the chamber by cryo-pumping. The ignition source was probably a hot wire level sensor, a platinum wire heated to above the ignition temperature of the mixture.
The ROOT CAUSE could be identified in an inadequate purging procedures and lack of independent assessment of the tank composition.
Facility
- Application
- Non-Road Vehicles
- Sub-application
- Aerospace
- Hydrogen supply chain stage
- All components affected
- cryogenic tank
- Location type
- Unknown
- Operational condition
Emergency & Consequences
- Number of injured persons
- 0
- Number of fatalities
- 0
- Environmental damage
- 0
Event Nature
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Presumed ignition source
- Hot surface
References
- Reference & weblink
Mishap no 31 in <br />
P. L. Ordin, Review of hydrogen accidents and incidents in NASA operations, 1974, NASA TM X-71565<br />
https://ntrs.nasa.gov/citations/19740020344Lowesmith et al., Safety issues of the liquefaction, storage and transportation of liquid hydrogen: An analysis of incidents and HAZIDS, Int. J. Hydrogen energy (2014) https://doi.org/10.1016/j.ijhydene.2014.08.002
Hankinson and Lowesmith, Qualitative Risk Assessment of Hydrogen Liquefaction, Storage and Transportation, FCH JU project IDEALHY, Deliverable 3.10 (2013)<br />
confidential<br />
(accessed October 2025)Hankinson and Lowesmith, HAZIDs for Hydrogen Liquefaction, Storage and Transportation , FCH JU project IDEALHY, Deliverable 3.11 (2013)<br />
https://www.idealhy.eu/uploads/documents/IDEALHY_D3-10%20HAZIDs_Liquefa… />
(Only summary publicly available, accessed October 2025)
JRC assessment
- Sources categories
- ORDIN
