Event
- Event ID
- 290
- Quality
- Description
A tube trailer carrying compressed hydrogen was travelling on a highway, when the drivers heard suddenly heard the sound of leaking gas. They stopped and discovered that that gas was escaping from the fusible plug of one of the cartridges, so traffic was restricted.
The KHK report does not provide information on if and how the leak was stopped, and on the reasons for the failure. Information on how the emergency was handled is also missing.- Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- leak no ignition
- Macro-region
- Asia
- Country
- Japan
- Date
- Component involved
- TPRD (burst disc)
- Failure mode
- premature activation & venting
- Initiating cause
- unknown
- Root CAUSE analysis
The INITIATING CAUSE was the opening of the thermally-activated pressure relief device (TPRD), expected to activate in case of temperature increases.
Nothing is known on the reason. Since no pressure anomaly was reported, it is plausible to assume that the TPRD failed pre-maturely due to material defect. The KHK report attributed the ROOT CAUSE to “inspection failure”, without however explaining why the inspection failed.- Root causes
- Date entry in HIAD
- 30/08/2025
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- CGH2 tube trailer
- Hydrogen supply chain stage
- All components affected
fusible plug, TPRD
- Process temperature range [C]
- ambient temperature (-50°C to +50°C)
- Process pressure range [MPa]
- medium to high pressure (10 to 50 MPa)
- Location type
- Open
- Location
- highway or similar
- Operational condition
- Pre-event occurrences
There were 22 long tubes on the trailer
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Post-event summary
The only information availabe is that "traffic was restricted".
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Release temperature [°C]
- 25
- Probable IGNITION SOURCE
References
- Sources categories
- KHK
- Reference & weblink
High Pressure Gas Accident Cases Database of the KHK (High Pressure Gas Safety Association):
https://www.khk.or.jp/public_information/incident_investigation/hpg_inc…
(accessed May 2025)
