A hydrogen leak occurred at a plant's hydrogen fill station when a vendor's hydrogen fill truck trailer pulled away after filling and caught an improperly stored hydrogen fill line. The driver of the hydrogen truck trailer did not properly stow the hydrogen fill line after filling and failed to verify that the hydrogen fill line was clear of the trailer prior to departure. As the driver pulled away from the fill station, the hydrogen fill line caught on the trailer and subsequently pulled on the hydrogen fill station's ground storage tubes distribution manifold. The force of this pull bent the plant's hydrogen distribution manifold and hydrogen began leaking from a threaded connection and from the hydrogen fill line. The truck trailer driver reported hearing a "pop and hissing sound", stopped the truck movement, and then promptly left the truck to report the incident at approximately 6:45 PM. The local fire department was contacted and the building was evacuated. The fire department arrived by 8:00 PM, along with the hydrogen vendor's service technician, to isolate the hydrogen leak. The hydrogen leak at the plant's hydrogen ground storage system was stopped by closing the individual valves on each hydrogen storage tube, thereby isolating the distribution manifold. At 10:00 PM, the all clear was given. Hydrogen operations were restored to the plant the next day by removing the damaged hydrogen ground storage unit and replacing it with a hydrogen tube trailer with concrete barriers installed to provide protection. The hydrogen leak from this event caused no hydrogen fire/explosion or personnel injuries.

Incident Date
Aug 25, 2008
  • Piping/Fittings/Valves
  • Piping
  • Vehicle & Fueling Systems
  • Fueling Hose
  • Hydrogen Storage Equipment
  • Hydrogen tubes
  • Vehicle & Fueling Systems
  • Gaseous Hydrogen Delivery Vehicle
Damage and Injuries
Contributing Factors
When Incident Discovered
Lessons Learned

Train personnel on delivery procedures and emphasize the safety aspects of hydrogen connections and disconnections, and verification of clearance for trailer movement prior to departure.
Provide site-specific delivery procedures and possibly include a checklist as a reminder of key safety items prior to departure.