Avoidance of collision risk

Over the past decades there has been a continuous increase in the public concern about general risk issues. The consequence of this trend is that whenever a catastrophic accident occurs - and receives media coverage - there is an immediate political and public demand for actions to prevent the same type of catastrophe in the future. Many of the past improvements in safety of marine structure have been triggered by disasters but there is a change in this trend nowadays. The maritime society is beginning, although slowly, to think and work in terms of safety assessment of individual ships instead of the much generalized prescriptive regulations which have evolved over the past 150 years. In line of these aspects it is clear that rational procedures for evaluating the consequences of accidental loads are highly desirable, not to say necessary. Collision risk or danger usually occurs in high sea, when navigation is led by Officer on Watch, as well as by traffic devices, when the breaking of rules is more significant: the rules have not been observed and/or efficient collision avoidance measures haven’t been taken in due time. Collision risk is an imminent risk, which requires immediate and firm measures for the re-establishment of the safety situation with respect to the collision with the target or other vessel that could bring about human accidents, serious damages to the vessel’s hull, pollution, wrecking, scuttling, etc. Collision risk is directly related to the „preventing method” of collision risk avoidance by assessing the collision probability together with the potential consequences. It is specific to „I” intersection angle of collision free courses