Event
- Event ID
- 697
- Quality
- Description
- Hydrogen as carrier gas was provided to a reactor gas chromatograph by several compressed hydrogen bottles. The bottles emptied rapidly, but the loss of carrier gas could only be detected when the gas storage pressure fell to a level to stop the flow to the chromatographer.
Later on, the leak was identified on the gas connection. - Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- Leak No Ignition (No additional details provided)
- Macro-region
- Europe
- Country
- United Kingdom
- Date
- Main component involved?
- Joint/Connection
- How was it involved?
- Leak & Formation Of A Flammable H2-Air Mixture
- Initiating cause
- Unknown
- Root causes
- Root CAUSE analysis
- The INITIATING CAUSE was an instrumentation connection with a 'serious leak'.
A ROOT CAUSE is not given. However, the failing to detect hydrogen and the quick emptying of the bottles highlights a lack of safety design of the laboratory and of effective safety procedures.
Facility
- Application
- Laboratory / R&d
- Sub-application
- chemical laboratory
- Hydrogen supply chain stage
- Hydrogen Storage (No additional details provided)
- All components affected
- chromatographer, compressed hydrogen storage
- Location type
- Confined
- Operational condition
- Unknown (No additional details provided)
Emergency & Consequences
- Number of injured persons
- 0
- Number of fatalities
- 0
Lesson Learnt
- Lesson Learnt
- In this event, a non-negligible amount of hydrogen was released in the laboratory without further consequences.
A chromatographer using hydrogen gas as a carrier is usually equipped with an internal safety sensor. However, this leak occurred outside on the line to the chromatograph housing, so that the internal gas detector could not detect the leak.
Nothing is known on the laboratory assets and its safety measures, such as the presence of forced ventilation, fume hoods and hydrogen safety sensors. If the latter were deployed, they were clearly not in the right place to detect this leak.
It can also be assumed that hydrogen could have formed a flammable mixture inside the laboratory and that an ignition source could have more serious consequences.
The fact that the leak was not detected until the storage was almost empty implies a lack of effective hydrogen detection in the laboratory. Moreover, a quick emptying of compressed hydrogen gas bottles should have been easily notices by the laboratory personnel, if the right procedure would have been in place and followed.
Event Nature
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Hole shape
- Other shape
- Presumed ignition source
- No ignition
References
- Reference & weblink
Event of the UK database ICHEME.<br />
https://www.icheme.org/knowledge/safety-centre/resources/accident-data/
JRC assessment
- Sources categories
- ICHEME