Introduction

Typically, the term “risk” is defined as either the product or a composite of (a) the probability or likelihood that any accident or limit state leading to severe consequences, such as human injuries, environmental damage, and loss of property or financial expenditure, occurs; and (b) the resulting consequences. In the design and operation of ship-shaped offshore units, as in many other types of structures, there are a number of hazards that must be dealt with in the process of risk assessment. Wherever there are potential hazards, a risk always exists.

To minimize the risk, one may either attempt to reduce the likelihood of occurrence of the undesirable events or hazards concerned, or contain, reduce, or mitigate the consequences, or both. In the lifecycle of a ship-shaped offshore installation, assessing managing, and controlling the risk is required so that it remains under a tolerable level. The risk management and control should, in fact, be an ongoing process throughout the lifecycle of an installation – that is, involving feasibility study, concept, or front-end design, detailed design, operation, and decommissioning. The different stages of the lifecycle will offer different opportunities for risk management and control, as may be expected.

Substantial efforts, such as the SAFEDOR project (http://www.safedor.org), are being directed by the maritime industry toward the application of the risk-assessment techniques together with risk-evaluation criteria to offshore design, operation, and human and environmental safety (e.g., Skjong et al. 2005).