As per the Danish Pilotage Act, it is mandatory to use a pilot for vessels passing to or from Danish ports and/or anchorages in Danish territorial waters, if the vessel;

1. Carry oil or have uncleaned cargo tanks (including slop tanks) that have not been rendered safe with inert gas
2. Carry chemicals –defined as IBC Code products type X, Y, Z
3. Carry gasses
4. Carry more than 5.000 mt bunker oil
5. Carry highly radioactive materials

Danish Pilotage Act can be found here (section 4)

The IMO recommendation:

According to SN.1/Circ. 263 of 23 October 2007, section 1.9 and 1.14 amendments to the recommendations on navigation through the Entrances to the Baltic Sea, the IMO recommends the use of pilot from Skagen to Gedser and vice versa for ships with a draught of 11 meters or more following Route T on their voyage through the Entrances to the Baltic Sea. The IMO Sailing Direction expresses an international acknowledgment of the fact that the entrances to the Baltic Sea are congested and difficult to navigate

To comply with the IMO recommendation ships should use a pilot when transiting internal and external Danish territorial waters (that is, passage without calling Danish port or anchorage etc.) through Route Tango and the Sound respectively:

Transit through Route-T (the IMO recommendation)

• All vessels with a draught of 11 metres or more.
• Vessels carrying highly radioactive material (INF code materials).

Transit through the Sound (the IMO recommendation)

• Loaded oil tankers with a draught of 7 metres or more.
• Loaded chemical ­tankers irrespective of size and gas carriers irrespective of size.
• Vessels carrying ­highly radio­active material (INF code materials).

It is worth to mention that the Danish Pilotage Authority reports all violations of the IMO recommendation to the flag state

For more detailed information please refer to the document attached under the below link:

Navigation Through Danish Waters

Source of the information:

DanPilot website 

The official website of the Danish Maritime Authority