Some technical aspects of spills in the transportation of petroleum materials by tankers

The petroleum industry is most concerned about safety and one which has an effective safety culture. This study analyzed the accident cycle in the sea transportation activities of the industry. The analysis was based on published data over the past 44 years involving spills of 1000 tonnes and above. Total spill volume was 4.27 mil tonnes with a mean of 64,000 tonnes and a standard deviation of 86,6000 tonnes. Total cleanup cost was estimated to be 17.8546 bil Int$, with a mean of 955.075 mil Int$, a standard deviation of 698.376 mil Int$. It was observed over the study period there seemed to be a cycle of about 10 years. There was a decreasing trend of spill volume. Crude represented 99% and the rest involved final products. About 65% of the tankers finally broke up and about 35% was associated with fire and explosion. Navigation error caused 42.5% of the accidents, storms and hurricanes caused 31.8% of the accidents, mechanical and maintenance related factors caused 18.2% of the accidents, engine failure represented 4.5% and other causes with about 3%. The highest number of deaths was recorded from the Independenta with 43.

► Accident cycle of about 10 years was observed.
► From January 1964 total oil spills from ships have almost reached 5 mil tonnes.
► Crude oil made up about 99% of material spilled.
► Crude risk analysis showed major cause of spill as navigation error.