STS and FSO methods are just as safe, if not more so, than docking the ships quayside. STS methods are also successfully used in other regions of the world. Accident rates have proven to be very low. Between 1996 and 2004 one company in the USA conducted 6,171 load transfers with just one single incident which resulted in five barrels of oil going overboard.


"Based on all information collected, INTERTANKO can not see that STS operations have caused any major oil spills."

(Letter from INTERTANKO (the international tanker association) 5th January 2006).

During the oil lightering process, the loading and unloading ships come together with the help of escort vessels (tugs). These tugs are moored to the tankers to prevent them running aground should the ship experience engine problems. All ships involved with oil lightering comply with the respective international IMO standard in terms of international rules and regulations and there are detailed procedures for pilot boats and tugs.

Contingency planning includes both preventative measures for possible occurences of serious pollution during lightering and having the appropriate equipment and manning on standby to tackle any accidental spillages. Barges equipped with booms, skimmers and oilbags are moored to one of the ships during cargo transfers and oil spill recovery booms are rolled out encircling the vessels. Should a spillage then occur it can be contained immediately with a much shorter reaction time than had the equipment been stored on land. Secondary contingency planning further includes a 200m NO-600-S category inflatable coastal boom. Reaction time is calculated to be 25 minutes.

Such contingency planning is specifically tailored for this type of operation, crews undergo comprehensive training and procedures are clearly stated in a detailed manual. Emergency preparation and environmental demands also include the handling of oil vapour, ballast water and noise levels and there are strict rules stating that the waters must be ice-free during lightering. The KLIF (Norwegian Pollution Control Authority) has now stated new and more stringent discontinuance criteria, which basically is a list of the factors that can lead to an operation having to be postponed.

The Norwegian Coastal Administration, the Norwegian Military's Command in Northern Norway, The Directorate for Civil Protection and Emergency Planning have each granted their support.