MARINE TRANSPORT OF DANGEROUS GOODS - RISK ASSESSMENT BASED ON HISTORICAL ACCIDENT DATA

In this paper marine transport of dangerous goods is surveyed on the basis of 151 accident case histories. Accident frequencies have been estimated for the different accident types (collisions, groundings, fire/explosions and structural damage) and are in the range of 1 x 10(-3) to 2 x 10(-2) per ship per year. Further estimates of the probabilities of spillage of at least 100 tons of cargo and/or fatalities in connection with the accidents have been made. The consequences measured in number of fatalities were compared for each cargo type (oils and chemicals) and it was shown that accidents involving oils were twice as frequent as accidents involving chemicals. However, the distribution of number of fatalities seems to be similar for the two types of goods. Concerning the local surroundings (port, coastal waters and open sea) it was shown that most accidents, both with small and large consequences, happen in coastal waters. The sizes of the spills have been modelled by linear regression based on accident type and the size of the ship. Fairly good correlation between the spill size and the size of the tanker was shown for groundings, structural damage and fire or explosions.