Event
- Event ID
- 392
- Quality
- Description
- A LH2 tank exploded causing injury and damage when hot wire sensors were used in tank after purging.
[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?
- Lh2 Storage Vessel
- How was it involved?
- Internal Explosion (H2-Air Mixture)
- Initiating cause
- Inadequate Or No Purge
- Root causes
- Root CAUSE analysis
- The INITIATING CAUSE was the production of an explosive air-hydrogen mixture inside a not properly purged tank.
Hot wire sensors were being used in the tank and caused the ignition
Nothing is known on the reasons for this inadequate purge, so that the ROOT CAUSE could be attributed generally to job factors, and to risk armament shortcoming, due to the use of wrong sensors.
Facility
- Application
- Hydrogen Stationary Storage
- Sub-application
- LH2 vessel
- Hydrogen supply chain stage
- Hydrogen Storage (No additional details provided)
- All components affected
- tank
- Location type
- Unknown
Emergency & Consequences
- Number of injured persons
- 1
- Number of fatalities
- 0
- Environmental damage
- 0
- Property loss (offsite)
- 0
Lesson Learnt
- Lesson Learnt
- Inadequate purging is a recurrent root cause for explosion during maintenance. Specifically purging of liquid hydrogen is a complex operation, implying effective warming up and gas replacement. In this case, the ignition source was probably a hydrogen sensor. If this assumption is correct, the hydrogen sensor had the goal to detect possible residual hydrogen. Whenever there is a possibility of hydrogen presence, ignition source must be avoided, including the sensors self.
Event Nature
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Release duration
- immediate
- Release rate
- n.a.
- Presumed ignition source
- Hot surface
- Ignition delay
- N
References
- Reference & weblink
Mishap no 54 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)
JRC assessment
- Sources categories
- ORDIN
