Order to Equinor – Oseberg A – investigation of incident involving electric shock

The incident occurred during reinstallation of a transformer associated with an electrostatic coalescer (EC) in the processing plant on Oseberg A, part of the Oseberg Field Centre.

Two people suffered an electric shock. One of them suffered an electric shock (hand-to-hand) upon coming into contact with a pipe flange and a live copper cable located inside the pipe flange. The other person also suffered an electric shock when they pulled the first person away from the copper cable.

Assessments from the investigation

The investigation team concluded that a number of factors contributed to the scope, interfaces and risk factors associated with the work not being adequately coordinated or understood. The work was planned and approved based on inadequate situational awareness, without established work processes being followed to the necessary extent. This gave the personnel involved at various levels an inadequate basis for understanding the risks and making decisions that could have ensured safe execution of the work.

This incident underscores the importance of allocating sufficient time and resources to multidisciplinary reviews of sub-activities under a work order, so that all parties involved have a shared understanding of the interfaces and risks. It also highlights the need for work to be described unambiguously and for site inspections to be conducted together with the personnel performing the work, both before the work begins and upon completion.

Furthermore, the incident underlines the importance of adequate supporting documentation and the necessary technical expertise linked to the systems and equipment that are in use, both among support personnel onshore and among relevant personnel offshore. This is of fundamental importance for sound risk assessments and prudent decision-making, especially in complex and multidisciplinary systems.

Actual and potential consequences

Two people suffered an electric shock from a high-voltage system in connection with the incident. The individuals concerned were taken ashore for medical examination. Both have since returned to their normal duties.

The investigation team concluded that the electric shock posed a risk of serious injury or death.

The investigation also shows that the facility has, over time, been operated in a manner that posed a risk of fire or explosion, because a potential ignition source was left exposed in a classified area.

Direct and underlying causes

The direct cause of the incident was contact with an uninsulated, live copper cable. The cable was live due to the backfeeding of current from connected transformers.

The investigation team has identified a number of underlying causes that may have contributed to the incident. These include:

• Knowledge of the EC system
• Operation and maintenance of the EC system
• Completion of previous work
• Planning and approval of the work
• Description of the work
• Reactivation of work order
• Lessons learned from previous incidents
• Activity level and capacity
• Inadequate observation of hazardous circumstances
• Information on risk of high voltage
• Compliance and risk management

A number of these factors influence and reinforce each another and must therefore be evaluated both individually and in context.

Non-conformities and improvement points

The investigation has revealed shortcomings at a number of levels related to a range of issues, including technical understanding and documentation, planning, multidisciplinary coordination, completion, learning and staffing. Collectively, these deficiencies contributed to the incident, and serious non-conformities have been identified.

Non-conformities were identified in the following areas:

• Inadequate risk management and use of own management system
• Inadequate planning and management of work on and operation of electrical installations
• Deficient ignition source control
• Inadequate technical documentation and expertise
• Deficient staffing and working arrangements

Order

Based on the investigation's findings, we have issued the following order to Equinor:

Pursuant to the Framework Regulations, Section 69 on administrative decisions, Equinor is ordered to:

A. Establish an action plan based on Havtil's investigation report following the incident involving electric shocks at the Oseberg Field Centre on 9 February 2026, including documented non-conformities and identified underlying causes.

The plan must describe the measures and their expected impact, as well as how their implementation and impact will be followed up. It must be made clear how the measures address the underlying causes identified by the investigation.

The plan must be submitted and presented to Havtil, and the measures must be implemented in accordance with the established plan.

See non-conformity 9.1.1 in the report (see also 9.1.2, 9.1.3, 9.1.4 and 9.1.5) and the underlying causes in section 7.2.

Cf. The Management Regulations, Section 6 on the management of health, safety and the environment, first paragraph, and the Management Regulations, Section 22 on the handling of non-conformities.

The deadline for establishing the plan and submitting it to Havtil is set to 1 March 2027.

The deadline for implementing the measures is set to 1 March 2028.

B. Conduct internal follow-up activities to verify that the implemented measures (ref. part A of the order) have had the intended effect.

The follow-up must include an assessment of whether the measures have been implemented as planned, whether they are achieving their intended results, and whether any further measures are needed.

The results of this work must be presented to Havtil.

Cf. The Management Regulations, Section 22 on handling of non-conformities, second paragraph.

The deadline for complying with this part of the order is set to 1 January 2029.

We are to be notified when the various parts of the order have been carried out.