North Sea operator Amerada Hess is to use double-hull oil tankers for all its UK offshore operations, following a study showing that this type of tanker cuts the the risk of oil spills by more than half.
The study, by Lloyd’s Register and Amerada, comes as increasing numbers of shuttle tankers are used to carry oil from offshore fields to onshore terminals. The tankers, with their frequent port visits and use of restricted waters, are more accident prone than trading tankers, the research found.
Researchers used tanker fleet statistics to evaluate risks, and identify remedies. Collisions and contacts with objects other than ships were cited as the main risks, responsible for 70% of polluting events. Nearly all accidents involving shuttle tankers were attributable to human error, making risk awareness vital.
While highlighting the effectiveness of double-hulled tankers, the research found that this type of ship accounted for only 22.6% of the world’s 708 tankers of 75,000 150,000 tonnes.
Using double-hulled ships would cut spills from accidents involving penetration of the inner hull by 75% and would cut overall oil spills by 52%, the study concluded.
Amerada Hess plans to follow this research with another Lloyd’s Register contract to study risk analysis further.
Risk Analysis for Shuttle Tankers and Mitigating Measures, Chungsheng Hu and Jeffrey Davison, Lloyd’s Register, 1998. Information: 0171 432 2667.