Fire from a hydrogen pipeline damaged by excavation works

Excavation work was performed nearby a buried pipeline of gaseous hydrogen. The excavation machine hit the pipeline causing an under-expanded jet fire.
Flames several metres high and a large amount of smoke came from an explosion in the middle of the fields.
The emergency services set up a safety perimeter of 2 km, blocking the traffic and evacuated two houses. A source reported that at least 20 km of the pipeline needed be emptied. Later, a specialised company repaired the pipeline.

No injuries. The excavation machine was burnt during the accident.

Additional investigations are in progress to understand why the third party company was not informed or has not transfer the information to the workers of the presence of the hydrogen pipeline.

The INITIATING CAUSE cause was the mechanical damage to an underground hydrogen pipeline
The ROOT CAUSE failure to inform on the xistence and position of the pipeline before the starting excavating works.

underground gas pipeline

Maintenance work (excavation for water drainage pipes) were performed nearby the pipeline.

No injuries. The excavation machine was burnt during the accident.

In Belgium a work declaration platform is mandatory for ground digging works. This had been adopted after the explosion of natural gas near Ghislenghien in 2004, caused under similar circumstances and with sever consequences.
The company executing the maintenance work near the pipeline was however unaware of its presence.
The investigation aims at identifying the cause of this lack of information and communication.