Located in Tysvær local authority in Rogaland country, the Kårstø land plant receives and processes natural gas and condensate from a number of North and Norwegian Sea fields.
Gassco is operator for the plant with Equinor as its technical service provider (TSP).
In connection with maintenance work being carried out by Equinor at the Kårstø plant, an electrical incident involving serious personal injury occurred on 25 July 2020.
The incident happened while a work team comprising two Equinor electricians was carrying out preventive maintenance on a 690V distribution switchboard in the T200 substation for Statpipe. When inserting a starter drawer, a short circuit occurred with subsequent arc flash. The person inserting the drawer (Electrician 1) was exposed to the arc flash energy and suffered second-degree burns to face, throat area, hands and knees. The other member of the team (Electrician 2) was present in the substation but at a safe distance, and was not exposed.
A fault in an electrical installation can cause an arc flash. The incident energy will typically increase in line with the short circuit level and/or trip time in the event of faults.
In the worst case, exposure to arc flashes with a high incident energy could be fatal even when the person is not in direct contact with conductive components.
Actual and potential consequences
One person was seriously injured.
The incident triggered a local alarm in the area, the shutdown of parts of the Kårstø plant and mobilisation of external emergency response resources. The Statpipe T-220 process train was shut down for about six days. Equinor has costed the material damage and other financial losses, repair of materials and downtime at NOK 7-8 million.
The investigation team has found the potential consequence of the incident to be the loss of a human life. This is based on the worst possible outcome if the person concerned had inhaled further quantities of toxic smoke and gas liberated by the arc flash incident.
Direct and underlying causes
A technical fault in the circuit breaker in the starter drawer was the direct cause of the incident.
The investigation has identified the following underlying causes of the incident:
- lack of follow-up/verification of the implementation of measures following the 2016 order
- inadequate planning and execution of the work
- lack of compliance with the procedure for ensuring safety against arc flashes
- inadequate information, training and experience transfer concerning the use of the modified test panel
- ageing and residual lifetime assessments (RLAs)
- risk assessments
- capacity and ability to deliver
- other conditions related to the work.
In connection with its investigation of the incident, the PSA team has identified nonconformities in the following areas:
- management and control
- work on and operation of electrical installations
- risk and residual lifetime assessments
- technical operating documents
- handling of nonconformities.
Earlier audits and orders
After earlier audits of electrical installations at Kårstø in 2016 and on the Draupner facilities in 2019, the Petroleum Safety Authority Norway (PSA) issued the following two orders of relevance to this incident:
- 2016 – order to Gassco and Equinor to initiate measures for improving personal safety when working on and operating electrical installations
- 2019 – order to Gassco to ensure electrotechnical expertise for following up electrical installations.
The PSA’s investigation has identified serious breaches of the regulations, and has given orders to both Equinor as TSP and Gassco as operator.
Equinor has been given the following order.
Pursuant to section 69 of the framework regulations on administrative decisions, Equinor is ordered to take the following action at the Kårstø plant.
1. Identify, initiate and follow up measures to ensure that the management system is complied with and that the management of risk associated with the ageing and deterioration of the technical condition of electrical equipment and installations comprises the activities, resources, processes and organisation required to ensure prudent operation and continuous improvement. See section 11 of the framework regulations on risk reduction principles and sections 6, 11, 16, 21 and 22 of the management regulations on management of health, safety and the environment, on the basis for making decisions and decision criteria, on general requirements for analyses, on follow-up and on handling of nonconformities respectively. See sections 10.1.1, 10.1.3 and 10.1.6 of the report.
2. Systematically review the company’s governing documents relating to work on and operation of electrical installations, and initiate the necessary measures to ensure that:
a. responsibilities, authority and roles are unambiguously defined, understood and complied with
b. necessary procedures and instructions are prepared, tailored to plant-specific conditions and complied with
c. existing training programmes are evaluated and that measures are initiated to ensure that relevant training modules are tailored to the nature of the plant and to job categories.
See sections 45, paragraph 2 and 60, paragraph 1 of the technical and operational regulations on procedures and on work on and operation of electrical installations respectively, and section 8 of the management regulations on internal requirements. See section 10.1.2 of the report.
3. Present a binding timetable for the specified measures adopted for implementing points 1 and 2, including a description of possible compensatory measures to be initiated until the nonconformities have been dealt with. See sections 12 and 22 of the management regulations on planning and on handling of nonconformities respectively.
The deadline for presenting a binding timetable pursuant to point 3 is 29 March 2021. The deadline for complying with point 2 of the order is 4 October 2021 and point 1 is 15 December 2021. We must be notified when the order has been complied with.
Gassco has been given notice of the following order.
Pursuant to section 69 of the framework regulations on administrative decisions, Gassco is ordered to take the following action.
1. See to it that Equinor ASA initiates and follows up the necessary measures at the Kårstø plant to comply with points 1, 2 and 3 in the order given to Equinor following the investigation of the electrical incident with serious personal injury at the Kårstø plant on 25 July 2020. See section 7, paragraph 2 of the framework regulations on responsibilities pursuant to these regulations and section 21 of the management regulations on follow-up.
2. Present a binding timetable for the specified measures adopted for implementing point 1, pursuant to section 12 of the management regulations on planning.
The deadline for presenting a binding timetable pursuant to point 2 is 29 March 2021. The deadline for complying with point 1 of the order is 15 December 2021. We must be notified when the order has been complied with.