Event
- Event ID
- 593
- Quality
- Description
This incident occurred on a hydrogen production device during the Great Hanshin Earthquake (Hyogo Prefecture Southern Earthquake). Hydrogen gas leaked from a pipe thread joint in a valve station. The leak was stopped by tightening the joint.
- 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
- joint/connection (threaded)
- Failure mode
- leak, no ignition
- Initiating cause
- loss of tightness (mechanical vibrations)
- Root CAUSE analysis
The INITIATING cause was the leak from a joint which became loose. The ROOT CAUSE was an earthquake.
- Root causes
- Date entry in HIAD
- 01/05/2025
Facility
- Application
- Hydrogen production
- Sub-application
- unknown
- Hydrogen supply chain stage
- All components affected
threated joint, pipe
- Process temperature range [C]
- ambient temperature (-50°C to +50°C)
- Location type
- Unknown
- Location
- unknown
- Operational condition
- Pre-event occurrences
Earthquake
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Emergency action
The leak was stopped by tightening the joint.
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)The first entry in HIAD was coming from RISCAD, which is now closed.
