The audit was conducted on 12 and 13 June 2023.


The background to the audit was two unintended incidents involving ignition and explosion connected to the venting of wash water from the auxiliary cooling circuit into an Intermediate Bulk Container (IBC, plastic container) on 27 May and 7 June 2023. After the first incident on 27 May, it was confirmed that hydrogen gas formed during the cleaning work, and this likely triggered the incident.

Based on the information received, we decided to carry out an audit to follow up Gassco and Shell's further handling of the incidents.


The objective of the audit was to obtain information about the incidents to clarify their extent, progression and causes, paying special attention to learning in order to prevent recurrence.

A further objective was to ensure that Gassco and Shell's handling of incidents complies with regulatory requirements.


We identified two non-conformities and two improvement points during the audit.


  • Deficient notification in the event of a hazard and accident situation
  • Deficient adherence to procedures

Improvement points:

  • Better recording, inspection and investigation of the cause of hydrogen formation to prevent recurrence
  • Better maintenance of the auxiliary cooling system

What happens next?

We have asked the company to report to us by 1 September 2023 on how the non-conformities will be addressed, and to give us their assessment of the improvement points identified.

We will follow up Gassco and Shell TSP's further investigation work as soon as their investigation report is available and has been sent to us.