Event
- Event ID
- 706
- Quality
- Description
A driver of a fuel cells vehicle terminated the refuelling and drove away without disconnecting the fueling hose from its vehicle.
The breakaway of the fueling hose was supposed to open, but did not. The receptacle fitting sheared off the vehicle.
The hydrogen contained in the hose between the dispenser shutoff valve and the vehicle check valve was released.- 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
- dispenser (breakaway)
- Failure mode
- failure to activate
- Initiating cause
- unknown
- Root CAUSE analysis
The INITIATING CAUSE was the tearing of the hose and the braking of the receptacle fitting on the vehicle.
The ROOT CAUSE was the error of the driver which forgot to disconnect the hose from the vehicle. CONTRIBUTING CAUSE was the fact that the breakaway system, designed to mitigate the consequences of these cases, did not operate as from design.
Tests of the breakaway, performed after event, showed that the breakaway operated at 210 lbs (95 kg), which was above the design value of 133 lbs (60 kg). This was very probable not a manufacturing error, but an installation error. It is further unclear who was supposed to detect this mishaps: could the station have performed regular check?- Root causes
- Unknown
- Date entry in HIAD
- 30/12/2025
Facility
- Application
- Road vehicles
- Sub-application
- FCEV (LDV)
- Hydrogen supply chain stage
- All components affected
breakway, nozzle, receptacle, check 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
- unknown
- Operational condition
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
In-depth data
- Release type
- gas
- Involved substances (% vol)
- H2 100%
- Release temperature [°C]
- 25
- Probable IGNITION SOURCE
References
- Sources categories
- H2TOOLS
- Reference & weblink
Events in database H2TOOLS
https://h2tools.org/lessons/hydrogen-fueling-dispenser-nozzle-drive-away
(accessed December 2025)