Use constraints: 1) The locations of the vessels are based on the homeport announced and are not precise (even more so since the vessels are often out at sea). Also, it should be noted that when viewing at a small scale (zoomed out), the vessel symbols in a certain port will unavoidably cluster and eventually merge. 2) Some of the characters in the place - and vessel names do not show correctly on different systems. We have attempted to add instructions concerning these characters in the end of each of the data files. These characters are: - ä : a with umlauts - ö : o with umlauts - å : a with a circle - ø : o with a slash - ü : u with umlauts.

The information about response vessels was gathered from the states surrounding Baltic Sea (along with information about other emergency capacities) by HELCOM and delivered to Finnish Environment Center as text files (tables). These were transformed to a shape file, using the homeport mentioned as the original location of each vessel. The dataset was further edited in order to situate the vessels to the sea in front of the ports. In December 2004, response vessel information for Estonia, Denmark, Finland and Poland was updated. In 2005 HELCOM amended the dataset projection from the original World Mercator to ETRS 1989 LAEA. The dataset is revised and updated annually. In March-April 2008, Estonian, Finnish, Latvian, Polish and Russian details were updated. In 2011 all data was updated in BRISK project.

The latest updated was done by HELCOM Secretariat in 9/2016.