Well Interventions Have Potential for Causing Major Accidents

The Petroleum Safety Authority Norway (PSA) is concerned that risk factors that may cause major accidents do not receive sufficient attention during planning and implementation of well interventions.

A systematic review of incidents from all operating companies in recent years reveals a potential for major accidents. This is confirmed in a report from SINTEF Technology and Society, commissioned by the PSA.

"We believe that the balance between the attention to safety risks related to individuals, and more complicated circumstances that may cause major accidents, is not good enough", says PSA Technical Supervisor for drilling and well technology, Stein A. Tonning.

Live wells
SINTEF emphasizes the major accident potential related to pressurized (live) wells in the report "Leakage related to cable operations - the importance of technical and operational factors for leakage with major accident potential."

Traditionally, we are most concerned about hydrocarbon leakage (gas leakages) in the production process itself. Cable operations are the most common well intervention. The report is based on investigations as well as experiences from contractors and operators that carry out cable operations on the shelf.

In the shadowB
"There is considerable interest in individual cases related to personal safety, which are easy to communicate. More complex factors which may cause major accidents are rarely in focus," Tonning emphasizes. He hopes that increased understanding of the major accident potential will lead to further reduction in the number of leakages. "The goal is for the Norwegian shelf to lead the way in reducing the risk related to hydrocarbon leakages", he emphasizes. Understanding risk The report concludes that systematic work in planning, analysis and implementation contributes to safer operations and that understanding risk is important in order to capture the potential for major accidents. It illustrates a set of leakage scenarios that describe various deviations and barriers that may prevent them.

The project is part of the PSA's "Risk level on the Norwegian shelf" and was presented on 30 August to representatives of operating companies and contracting companies. The meeting was concluded with an agreement for extended cooperation on challenges, risk reduction and standardization of well interventions on the Norwegian shelf. Aker Kvaerner Well Service has taken the initiative for this cooperation and the first meeting will be held on 6 December this year.

A reminder
Henning Boge is responsible for the well intervention group in ConocoPhillips. He believes it is important to broaden one's perspective and thinks the report from SINTEF in this respect is a reminder. In the industry meeting Boge emphasized that simple and complex risk factors can not be detached from one another.

"The total of all reported small injuries is a barrier in itself, and consequently helps prevent serious injuries. We have come a long way in reporting. It is very unlikely that an incident can be kept quiet.

Borge emphasized that individuals in themselves are barriers for major accidents. However, he emphasized that it is crucial to have a basic understanding of the risk elements.

"Several of the jobs we execute may become routine. Competence and experience is important, but simultaneously we need the keen eye - people who ask new questions and are able to see the work process from the outside," he adds.

In addition, ConocoPhillips Computer Security Consultant Øystein Lid believes it is important that each player on the shelf has a comprehensive HSE focus reaching beyond its own work operations.

"Consequently, we must take a comprehensive look at the facility's potential for major accidents, he concludes.