ABSTRACT
All human activities involve risk. In marine environment a vehicle or structure has to accept a certain amount of risk to life and property, which includes the vehicle or structure as well as its cargo. The risks can be due to varied and multifarious reasons. An accidental hazard may take place due to one or more risk factors occurring simultaneously causing loss of life and property. A design with absolute safety or with zero risk may be possible but could be prohibitively costly and unaffordable. Therefore, it is necessary to define an acceptable safety level such that increased safety may not be worth the cost. Further, this safety level must be acceptable to all the stakeholders such as the builder, the owner, statutory authorities, classification societies, operating personnel and society at large. With fast-changing technologies as well as trade demands and patterns leading to larger and sophisticated ships, platforms for oil and gas production moving into deeper and dangerous waters and the demand for high-performance vehicles for various applications and novel naval application vehicles, satisfaction of conventional safety requirements may not be adequate and new safety features may have to be incorporated in the design of the product. Though details related to safety issues can be highlighted at the later stage of design, the safety-related design features must be established at the concept design stage itself. The feasibility of various safety features, their cost implications and their integration with all ship systems must be done as a part of concept design. Generally, the ship designers consider safety as a constraint on the design objective to be satisfied, an example being that the selected main particulars must satisfy stability requirements. However, in the present context of safety, it is no more a constraint and becomes one of the objectives of design that the marine platform must be safe up to a predefined level with acceptable cost implications. In this chapter, first, the various safety issues related to operation of marine vehicles and platforms are discussed and their design implications are highlighted. Following this, a short discussion on rule-based design is done highlighting the need for risk-based design (RBD), and finally, the formal safety assessment (FSA) methodology leading to RBD is discussed.
