CGH2 tube trailer roll-over

A compressed hydrogen trailer-tractor overturned on a highway. The vehicle left the road on Sunday afternoon for unknown reasons, broke through the guardrail and tipped over about six meters from the motorway, lying on the side. The trailer was carrying nine tubes, not completely full. The sources report a value of the total load of 1200 – 1500 litres of hydrogen.
The valves, which were secured by special protective devices, were not damaged in the accident, and not loss of containment occurred.
The emergency services closed one lane and released the hydrogen to flow out in a controlled manner. The work lasted several hours. The truck was up righted and recovered with a crane in the evening.

INITIATING CAUSE was a traffic accident. In absence of information on drivers and driver behaviours, the ROOT CAUSE can be attributed generically to a human error (wrong maneuvre)

roll over

DESCRIPTION
It is unclear if the value provided for the hydrogen inventory refers to the volume of the gas at standards condition, or to the volume of the tubes which were containing hydrogen. In the former case, a negligible amount of 0.14 kg of hydrogen is calculated. In the latter case, approximately 21 kg. The second option is more credible, because one does not need 'several hours' to relase 140 g.

The driver suffered minor injuries and was taken to hospital for observation.
e total damage was initially estimated at around 100,000 euros.

It did not come to an accidental release, what suggest that the trailer design was enough robust to guarantee that the tubes remained in place during roll-over. it also helped the fact that the collision with the ground did not involve the rear of the trailer, which is the most sensitive part to mechanical collision.