Failure of a compressed hydrogen cylinder in a laboratory

Event

Event ID: 116
Quality: 3
Description: Workers were connecting a compressed hydrogen cylinder, when a release of hydrogen occurred within a safety-box for flammable gases (a fire-proof safety cabinet).
During the emergency response procedures, the explosive atmosphere ignited and destroyed the safety-box completely.
A fire followed the explosion, which was extinguished by the company fire department. Due to the explosion two employees were seriously injured and one minor injured.
Event Initiating system: Hydrogen system initiating event
Classification of the physical effects: Hydrogen Release and Ignition
Nature of the consequences: explosion followed by a fire
Macro-region: Europe
Country: Germany
Date: 18/04/2005
Component involved: CGH2 cylinder(s)
Failure mode: internal explosion
Initiating cause: unknown
Root causes: Unknown
Date entry in HIAD: 28/02/2009

Application: Laboratory / R&D
Sub-application: CGH2 stationary storage
Hydrogen supply chain stage: hydrogen storage
All components affected: H2 gas cylinder, safety box
Process temperature range [C]: ambient temperature (-50°C to +50°C)
Location type: Unknown
Location: industrial area
Operational condition: MAINTENANCE
Pre-event occurrences: The hydrogen release occurred during the connection of a compressed hydrogen cylinder.

Corrective Measures: Nothing is now on the accident analysis conclusions. Nevertheless, the company recommended all users of hydrogen-gas-cylinders to immediately ensure that the following conditions are in place:
(1) All gas-cylinders are in a technically good condition;
(2) The fixed pipe system with all its components and devices are sealed;
(3) The operators are all well trained in handling hydrogen;
(4) The operators have a documented training in the connection procedures of cylinders.