Risk indicators for major hazards on offshore installations

In decision making under uncertainty there are two main questions that need to be evaluated: i) What are the future consequences and associated uncertainties of an action, and ii) what is a good (or right) decision or action. Philosophically these issues are categorised as epistemic questions (i.e. questions of knowledge) and ethical questions (i.e. questions of moral and norms). This paper discusses the second issue, and evaluates different bases for a good decision, using different ethical theories as a starting point. This includes the utilitarian ethics of Bentley and Mills, and deontological ethics of Kant, Rawls and Habermas. The paper addresses various principles in risk management and risk related decision making, including cost benefit analysis, minimum safety criterion, the ALARP principle and the precautionary principle.

Assessment of existing offshore structures for life extension

Laboratory observations of green water overtopping a fixed deck

Design errors can severely jeopardise safety and contribute to failures in construction and engineering projects. Such failures can have devastating economic, environmental and social consequences....

Reviewing the past to learn in the future: making sense of design errors and failures in construction

Mooring Integrity Management: A State-of-the-Art Review

With this paper we will summarize the operational experience of FPSOs in Norwegian waters as seen from the regulatory point of view. Reported incidents, challenges and lessons learnt in the years after the first production vessel came on stream will be described, and utilized in an assessment of risk. At the end of 2000, five production vessels are in operation on the Norwegian Continental Shelf. Norne FPSO has been on location in the Haltenbanken region since 1997. Petrojarl Varg has been on location in the North Sea since 1998. Asgard A has been on location in the Haltenbanken region since 1998. Balder FPU and Jotun A has been on location in the North Sea since 1999. In addition, there are three floating storage units; Polysaga, Njord B and Asgard C. Totally these vessels represent more than nineteen years of offshore experience.

Experience And Risk Assessment of FPSOs In Use On the Norwegian Continental Shelfi Descriptions of Events

The purpose of this paper is to review the worldwide historical structural failure data in the 1990s on offshore structures, and compare this with the present risk analyses of Norwegian offshore structures. The paper describes an overview of registered accidents to offshore structures based on the databases WOAD and CODAM. The accident data is given for fixed platforms, jack-ups and for floating platforms. Estimates of risk level in annual frequencies and PLL values are given for each platform type. The paper concludes that: • The risk connected to mari ne operations and structures give a significant contribution to the total risk. • The historical risk to marine operations and structures is significant higher than the results from risk analyses. • Neither component nor system based reliability analyses of structures give adequate descriptions of the real risk connected to structures. • Human errors are probably the dominating cause of accidents connected to structural failure.

Roger L. Leonhardsen

Papers

Experience And Risk Assessment of FPSOs In Use On the Norwegian Continental Shelfi Descriptions of Events

On the Risk of Structural Failure On Norwegian Offshore Installations