COSAC

COSAC is a computerised tool for efficient risk assessment in the early phases of an offshore field development, which:

• utilises expert experience gained through more than 20 years of risk analysis
  
• enables fast and efficient presentation of the main features of a new field development
  
• identifies critical areas that could be in conflict with risk acceptance criteria
  
• provides a coarse ranking of concepts in an early screening phase of a project.

In 1992 Scandpower developed a Concept Safety Catalogue for safety evaluation purposes in the early phases of a field development. The work was carried out in co-operation with Norsk Hydro. The Catalogue was devised as a tool to aid in the identification and evaluation of safety advantages. It is comprehensive and intended for use during feasibility and concept studies. Moreover, it will offer support in the early project phases by helping to fulfil Authority and Operators safety requirements. The Concept Safety Catalogue was updated in 1995 and expanded at the request of Saga Petroleum. In 1996 a joint industry project was initiated, the objective being to develop a PC-tool based on the Catalogue. The result is COSAC.

The user defines the concept by a selection of relevant building blocks. Each building block is analysed by a check list of risk factors.

COSAC is structured as a Building Block system reflecting 12 Main Concept Elements of an offshore field development. Having identified the Main Concept Elements cosac provides Building Blocks for each Main Concept Element. In this way a field development concept can be described by a number of Building Blocks.

COSAC ANALYSIS AND RESULTS are tailor made for concept evaluation and screening. Its aim is to increase the safety of new offshore developments by utilising 20 years of experience gained from risk analyses. Some of the main features of cosac include reducing uncertainty, improving the quality and efficiency of early phase safety evaluation of new concepts, and also in the modification of existing installations. cosac provides a safety score for every risk factor associated with an offshore field development concept. A low score indicates safety concerns and/or lack of documentation of important safety issues. Therefore, a low safety score in cosac puts these issues in focus. In addition the user is provided with information on how to resolve the problems identified by cosac. cosac offers a safety profile for each offshore development concept. The profile alone or the average safety score can be used to compare different alternatives. The cosac results give the user the possibility to allocate resources to risk reduction in a cost-effective way. Our hope is for the cosac tool to be used in offshore operations by every operator and engineering company in their efforts to improve efficiency of both oil production and safety.

COSAC will:

• utilise expert experience gained through more than 20 years with risk analyses
• enable fast and efficient presentation of the main safety features of a new field development
• identify critical areas which could be in conflict with risk acceptance criteria
• provide a coarse ranking of concepts in an early screening phase of a project.

Companies participating in the cosac R&D project:

• Norsk Hydro ASA
• Saga Petroleum ASA
• Statoil
• Scandpower A/S