The International Maritime Organization (IMO) has introduced new requirements for safety equipment on board. According to Resolution MSC.74 (69), Annex 3, all SOLAS vessels had to have installed AIS (Automatic Identification System) transponders in the period from 2002 and 2004 according to the pre-defined deadlines for different categories of ships.

The AIS system allows all AIS equipped vessels to automatically exchange data regarding navigation and vessel specific information among the vessels themselves or to shore-base AIS installations. The AIS data is shown on suitable displays on board the ship, and will help foresee dangerous situations and facilitate communications between the vessels involved, thus increasing safety at sea.

As the AIS transponder is communicating on a VHF data-link, the AIS is able to track vessels that might be out of sight, even for the radar, and to “see around corners” and obstacles, so that mariners will be able to prepare the navigation changes before visual contact is made.