In light of the the continuing number of casualties where the misuse of VHF marine radio has been established as a contributory factor, the MCA has decided to re-issue the guidance notice on the appropriate use of very high frequency (VHF) radios. Additionally, the appropriate use of the Automatic Identification System (AIS), especially with regard to collision avoidance, has been highlighted.
“The IMO and wider maritime community has noted with concern the widespread misuse of VHF channels at sea,” the guidance asserts. “Although at sea VHF makes an important contribution to navigation safety, its misuse causes serious interference and, in itself, becomes a danger to safety at sea.”
As a result, IMO member governments have unanimously agreed to ensure that VHF channels are used appropriately and correctly. “It should be borne in mind that not all ships or marine craft carry or are required to carry AIS,” the guidance adds. “The officer of the watch (OOW) should always be aware that other ships, in particular leisure craft, fishing vessels and warships, and some coastal shore stations, including Vessel Traffic Service (VTS) centres, might not be fitted with AIS.”
It points out that the OOW should also be aware that AIS fitted on other vessels as a mandatory carriage requirement might, under certain circumstances, be switched off on the master's discretion and professional judgment. Users are, therefore, cautioned always to bear in mind that information provided by AIS may not be giving a complete or correct ‘picture’ of shipping traffic in their vicinity.
The key points of the guidance further advise that, while the use of a VHF radio transceiver may be justified on occasion as a collision avoidance aid, the provisions of the International Regulations for Preventing Collisions at Sea, 1972 (COLREG) should remain uppermost.
It also highlights that there is currently no explicit provision in the COLREG for the use of AIS information, however, the potential of AIS to improve situation awareness is recognised and AIS may be included as such in the future. The navigation safety related functions of AIS are to help identify ships, assist in target tracking and provide additional information to assist situation awareness. Limitations of AIS, with respect to mandatory carriage based on vessel types and sizes, have also been highlighted.
The full MCA report can be found at