Event
- Event ID
- 391
- Quality
- Description
During a welding operation on a LH2 fill line it was discovered that LH2 was still in the tank although it should have been drained. Hence the potential for a major explosion existed.
- Event Initiating system
- Classification of the physical effects
- No Hydrogen Release
- Nature of the consequences
- Macro-region
- North America
- Country
- United States
- Date
- -
- Component involved
- pipe (generic)
- Failure mode
- damage, no release
- Initiating cause
- inadequate or no purge
- Root CAUSE analysis
A deviation from procedures had occurred when purging was continued without power to the tank sensing probes in the LH2 tank at the after 400th cycle. Because of the undetected presence of LH2 in the tank, when gaseous nitrogen was introduced, it liquefied and blocked the system.
- Root causes
- Date entry in HIAD
- 01/11/2025
Facility
- Application
- Non-road vehicles
- Sub-application
- Aerospace
- Hydrogen supply chain stage
- All components affected
LH2 pipe
- Process temperature range [C]
- cryogenic temperature (below -50°C)
- Location type
- Unknown
- Location
- industrial area
- Operational condition
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Emergency action
none
In-depth data
- Release type
- no release
- Released amount (kg)
- 0
- Release pressure [MPa]
- 0.1
- Probable IGNITION SOURCE
References
- Sources categories
- ORDIN
- Reference & weblink
Mishap no 50 in
P. L. Ordin, Review of hydrogen accidents and incidents in NASA operations, 1974, NASA TM X-71565
https://ntrs.nasa.gov/citations/19740020344Hankinson and Lowesmith, Qualitative Risk Assessment of Hydrogen Liquefaction, Storage and Transportation, FCH JU project IDEALHY, Deliverable 3.10 (2013)
confidential
(accessed October 2025)Lowesmith 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
