In accordance with the Maritime Law (Official Gazette, No 181/04) and the Law about Plovput (Official Gazette No. 73/97), the basic activity of Plovput is related to safety of navigation and as such it is of interest for the Republic of Croatia. It comprises:

• Provision and maintenance of aids to navigation. There are about 1000 aids to navigation which assure the required level of safety of navigation in the internal and territorial sea of the Republic of Croatia;
• Maritime radio service which assures constant watch on emergency and safety frequencies (VHF DSC CH 70 and VHF CH 16) in order to protect human lives and property at sea. Maritime radio service functions as a 24 hours watch in 3 coast radio stations: Rijeka Radio, Split Radio and Dubrovnik Radio which make part of aids to navigation.

Aids to navigation should be in accordance with the international aids to navigation system, namely in accordance with the International Association of Lighthouse Authorities (IALA). Moreover, they should be in accordance with the Regulations about aids to navigation in the internal and territorial sea of the Republic of Croatia (Official Gazette No. 40/94), while the Maritime Radio Service should respect the regulations of SOLAS convention and International Radio Traffic Regulations. This means maintenance of the existing and the construction of new aids to navigation, as well as carrying out the radio service activities for the purpose of safety of navigation and protection of human lives at sea.

Aids to navigation are divided into: lighthouses (with or without personnel), coast lights, light beacons and lighted buoys, signal beacons and buoys, port lights, leading lights, sector lights, signal stations and coast radio stations.