Transfer of cargo oil

STS (ship-to-ship) operations refer to the transfer of cargo from the cargo hold of one tanker to that of another. The operation is mandated by a number of special safety procedures.

STS operations

In Danish waters, most STS operations take place in Aalbæk Bay at Frederikshavn in Northern Jutland or on Danish EEZ. In the tables below, you can find more information about the number of STS operations, where they are carried out and how much oil is transferred.

So far, no STS operations have been reported for Greenland waters.

In 2018 the first STS operation with liquefied gases was performed in Danish waters.

STS operations in Danish and Greenland territorial waters

Tankers carrying out STS operations in Danish and Greenland territorial waters are covered by the provisions of the order on STS operations.

Read the order on STS operations.

According to the regulations, STS operations must be carried out under the guidance and supervision of an approved STS operator and in accordance with the most recent international industry recommendations. The Danish Maritime Authority approves STS operators upon application. STS operators must pay the costs related to the approval. Approved STS operators must use a quality management system that ensures that their tasks are carried out in accordance with the provisions of the order.

List of approved operators.

The Defense Command, Naval Staff, as well as the Arctic Command must be informed about the transfer and tankers carrying out cargo transfers in Danish territorial waters are covered by the obligation to take a pilot in accordance with the pilotage act.

STS operations outside Danish territorial waters

As regards STS operations outside territorial waters, the provisions of United Nations' International Maritime Organization (IMO) apply. The regulations stipulate that the operation must be carried out in accordance with an approved plan, which is made on the basis of the ship's construction, equipment and valid industry guidelines for "best practice" in the area. In addition, the operation must be reported to the relevant authorities in the coastal State.

Furthermore, HELCOM (Baltic Marine Environment Protection Commission - Helsinki Commission) has developed a set of recommendations for guidelines on bunkering operations and ship to ship cargo transfer of oils in the Baltic Sea Area. HELCOM  is the governing body of the Convention on the Protection of the Marine Environment of the Baltic Sea Area.

Read more about HELCOM guidelines

In 2018, 62 STS operations were performed outside Danish territorial waters but inside the Danish EEZ. The quantity transferred however was only 151.627 tonnes of which only three operations involved the transfer of more than 5.000 tonnes. In all cases the transfer dealt with bunker oils, being transferred to small tankers approved to perform bunkering operations in Danish territorial waters. Bunker ships which subsequently distributed the bunker oils to other cargo ships for their daily power consumption.

Read more about STS operations..

Total quantity of oil/gas transferred (tonnes)


The Danish Maritime Authority carries out inspections of operations in Danish and Greenland waters on the basis of random checks. In the table below, you can find more information about the inspections carried out by the Danish Maritime Authority.

Number of inspections


Maritime Regulation and Legal Affairs