Event
- Event ID
- 718
- Quality
- Description
Two employees were working on a electric furnace under hydrogen atmosphere that had jammed. The furnace exploded. The employees sustained flash burns to their faces and were taken to the hospital, where they were treated and released later the same day.
The furnace had not been purged for 10 hours, as required by the manufacturer.- Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- Macro-region
- North America
- Country
- United States
- Date
- Component involved
- reactor / oven / furnace / test chamber
- Failure mode
- internal explosion
- Initiating cause
- inadequate or no purge
- Root CAUSE analysis
The workers were using a retrieval tool not suitable for servicing a hydrogen furnace. This may have been the IGNITION SOURCE for the explosion.
The furnace had not been purged for 10 hours, as required by the manufacturer.- Root causes
- Date entry in HIAD
- 01/01/2020
Facility
- Application
- Chemical industry
- Sub-application
- unspecified chemical process
- Hydrogen supply chain stage
- All components affected
Hydrogen furnace
- Location type
- Unknown
- Location
- industrial area
- Operational condition
- Pre-event occurrences
The furnace had not been purged for 10 hours, as required by the manufacturer. The retrieval tool the workers were using was not suitable for servicing a hydrogen furnace, and may have been the ignition source for the explosion.
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 2
- Post-event summary
They sustained flash burns to their faces and were taken to the emergency room at Petaluma Valley Hospital, where they were treated and released later the same day.
Lesson Learnt
- Lesson Learnt
This is a case of incident caused by failing to follow existing procedures. Furnace operation, even in case of repairs, should strictly follow manufacturer's requirements. In particular, in presence of hydrogen in the system, effective purging is a critical step.
Care should be taken in selecting retrieval tool avoiding them acting as ignition source.
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Probable IGNITION SOURCE
- Explosion type
- Deflagration
References
- Sources categories
- OHSA
- Reference & weblink
U.S. Department of Labor Occupational Safety & Health Administration OHSA incident report:
https://www.osha.gov/ords/imis/accidentsearch.accident_detail?id=170764…
