Event
- Event ID
- 933
- Quality
- Description
During maintenance work on a gas pipeline carrying hydrogen , a worker hears a leak at a bridge. The operator measures an concentration of 3% of the low flammability limit at few centimetres from the leak, and no detection beyond 25 cm. The area was highly ventilated. The technicians secured the area, isolated the section five hours later and started the controlled gas release. after two additional hours the pressure had reduced to zero and they started the nitrogen inerting. The pipe was repaired the next day.
- Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- leak no ignition
- Macro-region
- Europe
- Country
- France
- Date
- Component involved
- pipeline (generic)
- Failure mode
- rupture, no ignition
- Initiating cause
- unknown
- Root causes
- Unknown
- Date entry in HIAD
- 01/01/2018
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- Pipeline
- Hydrogen supply chain stage
- All components affected
hydrogen pipeline, 80 mm diameter, 75 bar pressure
- Process temperature range [C]
- ambient temperature (-50°C to +50°C)
- Process pressure range [MPa]
- medium pressure (2 to 10 MPa)
- Location type
- Open
- Location
- countryside or desert
- Operational condition
- Pre-event occurrences
The begin of the leak was unknown. The leak was detected during maintenance work, what does not mean that it started at that moment.
The pipeline section (diamater DN80) dated back to 1988.
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Emergency action
14.30 detection of the leak. Area secured,
19:15 Isolation of the pipeline section
20:00 Start controlled emptying
23:00 Pipeline pressure at zero, start of nitrogen injection
Day after: repair of the leak
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Release temperature [°C]
- 25
- Release pressure [MPa]
- 7.5
- Probable IGNITION SOURCE
References
- Sources categories
- ARIA
- Reference & weblink
Event description in the French database ARIA
https://www.aria.developpement-durable.gouv.fr/accident/43705/
(accessed September 2020)
