Event
- Event ID
- 1134
- Quality
- Description
A vehicle transporting 54 compressed hydrogen cylinders stopped at a railroad crossing and was struck from behind by a tractor trailer that did not slow down. Due to the impact, the cylinders were thrown from the vehicle. Three of them had the cylinder caps destroyed by hitting the road, broke the valves releasing hydrogen. The hydrogen was allowed to vent till emptying the cylinders without any intervention.
- Event Initiating system
- Classification of the physical effects
- Unignited Hydrogen Release
- Nature of the consequences
- leak no ignition
- Macro-region
- North America
- Country
- United States
- Date
- Component involved
- valve (generic)
- Failure mode
- rupture, no ignition
- Initiating cause
- impact, rollover, crash
- Root CAUSE analysis
INITIATING CAUSE was a traffic accident.
In absence of information on driver, the ROOT CAUSE is attributed generically to a human error (wrong manoeuvre).- Root causes
- Date entry in HIAD
- 25/10/2024
Facility
- Application
- Hydrogen transport and distribution
- Sub-application
- CGH2 cylinders truck
- Hydrogen supply chain stage
- All components affected
valve
- 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
- highway or similar
- Operational condition
- Description of the facility/unit/process/substances
DESCRIPTION OF THE UNIT
According to PHMSA, each cylinder contained 300 gas-cubic feet of hydrogen. Three cylinders were damaged and released 900 gas-ft3. If these values are correct, it corresponds to ca. 2.1 kg of hydrogen released. The total transported hydrogen, in 54 cylinders, was then ca. 39 kg
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Currency
- US$
- Property loss (onsite)
- 45.045
- Post-event summary
The driver of the other truck that struck the rear of the Linde truck was killed upon impact.
- Emergency action
No attempt to stop the leak was made, because the safest way to deal with was to allow hydrogen to vent and empty the cylinders without
Lesson Learnt
- Lesson Learnt
According to the shipping company, this accident was beyond our drivers control. The cylinders were adequately secured for normal transportation, but the impact was very violent Still according to the company, there was not a possibility of not having the cylinders leave the truck. In absence of accurate frequency of failure as function of the impact force, it is impossible to draw an independent and fact-based opinion on the need of a better design.
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Released amount (kg)
- 2.1
- Release temperature [°C]
- 25
- Release pressure [MPa]
- 16.5
- Probable IGNITION SOURCE
References
- Sources categories
- PHMSA
- Reference & weblink
Incident E-2005040157 of the US Pipeline and Hazardous Materials Safety Administration PHMSA:
https://portal.phmsa.dot.gov/analytics/saw.dll?Portalpages&PortalPath=%…
(accessed September 2024)
