Event
- Event ID
- 291
- Quality
- Description
- A trailer was transporting 35 tubes of compressed hydrogen (7 m3), when five of them fell, breaking the valves and releasing gas, which ignited on three of them.
The caps designed to prevent the tubes from falling had not been attached before starting the journey. - Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- Fire (No additional details provided)
- Macro-region
- Asia
- Country
- Japan
- Date
- Main component involved?
- Valve (Shut-Off)
- How was it involved?
- Rupture & Formation Of A Flammable H2-Air Mixture
- Initiating cause
- Impact, Rollover, Crash
- Root causes
- Root CAUSE analysis
- The INITIATING CAUSE was the falling of compressed hydrogen tubes from a trailer.
The KHK report attributed the ROOT CAUSE to “mishap”, without however clarifying further if this was a human error (failing to follow the procedures) or a lack of clarity of the procedures.
Facility
- Application
- Hydrogen Transport And Distribution
- Sub-application
- CGH2 tube trailer
- Hydrogen supply chain stage
- Hydrogen Transport (No additional details provided)
- All components affected
- valves
- Location type
- Open
- Operational condition
- Pre-event occurrences
- The trailer was transporting 35 tubes. Assuming that the 7 m3 value provided by the KHK report refers to the total water capacity, a total of 100 kg of transported hydrogen can be calculated, further assuming a pressure of 200 bar.
Emergency & Consequences
- Number of injured persons
- 0
- Number of fatalities
- 0
- Emergency action
- The leak was discovered by employees which heards a hissing sound. The area was secured, and the neighbouring packaging stations, which were non in function, were locked out. The semi-trailer was moved for emptying and purging with nitrogen.
To identify the location of the leak, the operator carried out gas leak detection checks using a "thousand bubble" gas leak detector and an explosimeter.
Event Nature
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Released amount
- 15
- Presumed ignition source
- Mechanical sparks
References
- Reference & weblink
High Pressure Gas Accident Cases Database of the KHK (High Pressure Gas Safety Association): <br />
https://www.khk.or.jp/public_information/incident_investigation/hpg_inc… />
(accessed May 2025)
JRC assessment
- Sources categories
- KHK
