Event
- Event ID
- 930
- Quality
- Description
A leak occurred on a rack containing 12 cylinders of hydrogen (50 l at 200 bar each) delivered by a lorry inside the fenced storage area of a bulb manufacturing plant.
The plant’s safety manager closed access to the area, had the other lorry drivers on the site cut off their ignitions, and made them evacuate. The firefighters tested the air with an explosimeter and stopped the leak by closing the gate valve located on the outside of the rack. The valve was used to transfer hydrogen from the cylinders to their points of use.
The rack had been delivered by a crane lorry. Each of the top four corners of the rack was fitted with a steel ring that was used to lift the rack off the lorry. The gate valve was opened when one of the four lifting chains used to lift the rack off the lorry accidentally wrapped around it.
- 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
- valve (shut-off)
- Failure mode
- rupture, no ignition
- Initiating cause
- impact, rollover, crash
- Root CAUSE analysis
INITIATING cause was the accidental opening of the main hydrogen valve during unloading of the lorry.
- Root causes
- Date entry in HIAD
- 01/01/2018
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- CGH2 cylinders truck
- Hydrogen supply chain stage
- All components affected
cylinders
- 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
- industrial area
- Operational condition
- Pre-event occurrences
The lorry had been delivered to destination and the unloading of the rack of hydrogen cylinders was ongoing by means of the lorry crane
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Post-event summary
The ARIA report (see references) does not provide quantitative assessment of the amount of hydrogen released.
- Emergency action
13:30 Hydrogen release started - The plant’s safety manager closed access to the area, had the other lorry drivers on the site cut off their ignitions, and commanded an evacuation.
The firefighters tested the air with an explosimeter and stopped the leak by closing the gate valve.
15:00 The firefighters left and the plant resumed normal operations.
Lesson Learnt
- Corrective Measures
According to the ARIA report (see references), the operator took the following two corrective measures:
i) stopped deliveries of this type of rack ,
ii) replaced it by one with 16 cylinders, fitted with a cover and a central lifting ring.
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Release temperature [°C]
- 25
- Release pressure [MPa]
- 20
- Probable IGNITION SOURCE
References
- Sources categories
- ARIA
- Reference & weblink
Event description in the French database ARIA
https://www.aria.developpement-durable.gouv.fr/accident/44315/
(accessed September 2020)
