Multivariate Analysis of Worldwide Tanker Casualties1

Abstract

Previous research on the relationships between oil tanker characteristics and casualty events suggests that vessel flag, size, and age may be important determinants of casualty rates. These studies have been bivariate primarily, examining one factor at a time, providing uncertain results given the interdependent nature of the factors affecting tanker casualties, such as age and size. This paper describes a multivariate analysis of the relative effects of vessel flag, size and age on the casualty rates of oil tankers for the period 1969 to 1978. Among the findings discussed are: (1) vessels operating under certain flags of registry have much higher casualty rates than others in the world fleet; 2) smaller vessels exhibit higher casualty rates than larger ones; and 3) older vessels appear to be no more accident prone than newer vessels. With few exceptions, these basic findings are invariant with respect to accident cause and accident location.

Modelling Navigational Risk and Oil Spill Probabilities

“…Therefore, the incidence of minor, limited or major pollution is at least 13/206 (6-4 per cent) and at most 13/71 (183 per cent). Worldwide data on the incidence of pollution from tanker casualties 21 seem to indicate that about 10 per cent of collisions, groundings and strikings in harbour areas result in pollution, while between 22 per cent and 2£ per cent of those in coastal areas result in pollution. Combining these diverse sources of information, it would seem that an average of 1 £ per cent for harbours, rivers and coastal areas would seem reasonable and consistent with the Marine Casualty database.…”