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Clean Hydrogen Partnership

Nozzle disconnection difficulty

Event

Event ID
705
Quality
Description
A fuel cell and hydrogen vehicle terminated the refueling, but the dispenser nozzle could not be completely disconnected from the the vehicle receptacle. It could be disconnected only after several attempts. The cover of the nozzle interfered with the disconnection operation. It was not a problem of malfunction of the nozzle. It could be easily disconnected when withdrawn along its axis. However, because if its weight, a misalignment could take place which made difficult the desconnection.

[H2TOOLS]
Event Initiating system
Classification of the physical effects
No Hydrogen Release
Nature of the consequences
Macro-region
North America
Country
United States
Date
Main component involved?
Dispenser (Nozzle)
How was it involved?
Malfunctioning
Initiating cause
Wrong Operation
Root causes
Root CAUSE analysis
It is plausible to assume the first prototype design of the hose and nozzle assembly were very heavy and of difficult handling.

Facility

Application
Road Vehicles
Sub-application
FCEV (LDV)
Hydrogen supply chain stage
Hydrogen Transfer (No additional details provided)
All components affected
nozzle, receptacle
Location type
Open
Location description
Unknown
Operational condition

Emergency & Consequences

Number of injured persons
0
Number of fatalities
0

Lesson Learnt

Corrective Measures
H2TOOLS reported the following actions:
Manuals showing the correct connecting and disconnecting procedures were established for each fueling dispenser.
Separate manuals were needed since the shape of the grip differs from dispenser to dispenser.

Event Nature

Release type
gas
Involved substances (% vol)
H2 100%
Presumed ignition source
No release

References

Reference & weblink

Events in database H2TOOLS<br />
https://h2tools.org/lessons/hydrogen-fueling-dispenser-nozzle-detached<… />
(accessed December 2025)

JRC assessment