Hydrogen fire from a LH2 tanker

The incident occurred outside a fuel cells manufacturing facility. While preparing for transfer of liquid hydrogen from tanker truck to a stationary storage tank, a release of hydrogen occurred, which vaporised into a hydrogen cloud and ignited in a flash fire and concussion loud enough to be heard inside the nearby building (the building’s seismic event detectors went off).
A small amount of hydrogen gas continued to escape from the tanker and burn for almost eight hours, until a specialist of the truck delivery company arrived to manually shut off a critical valve.
In the meantime, emergency response crews called to the scene sprayed water across the hydrogen tank as a precautionary cooling measure. The fire brigade let the fire burn out and kept dousing the tanker until the day after to reduce the temperature and to minimise possible the risk of explosion. A technician of the company delivering the hydrogen arrived on the site and isolated the leak by shutting off a valve.
As described in the PRESLHY report (see references), the driver had just terminated a first unloading of the tank. The manual valve connecting the tanker to stationary storage was apparently left in an open position after the first unloading. The driver next failed to perform the required procedure of seven purges intended to eliminate contaminants and water from the piping before connecting the hose for the second unloading. He then opened the pneumatic valve before connecting the hose, which, due to the open manual valve, resulted in a direct release of liquid hydrogen into the ambient. The liquid immediately vaporized into a hydrogen cloud and quickly ignited.
The driver suffered minor burns to his face but there were no other injuries or damage to the plant.

The INITIATING CAUSE was a series of actions by the tanker driver not in line with the procedure.
the ignition is thought that a static electricity built up by the rush of vaporising gas.

Nothing is known on the design or operation deficiencies which could have allowed the incident. In absence of further details, it is therefore to conclude that the ROOT CAUSE has been a human error and a failure to properly train the personnel.

valves, hose

The tanker truck was preparing to complete the second of two deliveries at the facility, by transferring liquid hydrogen from the tanker truck to a hydrogen bulk storage.

The driver escaped with only minor injuries. The fact that driver received only sunburn-type of injuries is due to the fact that hydrogen combustion produces a high output in the ultraviolet spectrum, thus radiant effects really are like common sunburn. Had he been actually immersed in the flame, his injuries would have been more serious.

The truck only received minor damage during the incident (see picture in PRESLHY report). After the manual valve was closed by the specialist, the truck was determined to be roadworthy and was returned to the company for inspection.

Company employees were evacuated, including those of a nearby company. An evacuation perimeter was created with a three-kilometre extension around the company. The company operations were stopped until the following day.

The emergency response crews called to the scene sprayed water across the hydrogen tank as a precautionary cooling measure. They let the fire burn out and kept dousing the tanker until the day after to reduce the temperature and to minimise possible the risk of explosion. A technician of the company delivering the hydrogen arrived on the site and isolated the leak by shutting off a valve.

Company emergency response personnel reacted as trained, the safety systems operated as designed, and the fire crews were able to manage the hydrogen fuel safely and effectively

According to the PRESLHY report (see references), this incident illustrated the need for "rigorous training on hydrogen properties and behaviour, not only for the operators of fuelling equipment but also for emergency responders and the general public".
(same words are used by H2TOOLS).

It is unknown which measures were taken by the company delivering LH2 . It is to assume that they improved training, to ensure the knowledge and the applications of the procedures.