October 2021, International Maritime Organization IMO Recognizing that incompatibility may exist between modified frequencies and channeling arrangements for the maritime VHF band, MSC.1 for equipment capable of NBDP and VHF radio communications covering both MF/HF Corrected /Circ.1460/Rev.2 guidelines. VHF radio communications equipment must comply with the ITU Radio Regulations (RR).

Guidance on Procedures for Updating Ship Navigation and Communications Equipment to Ensure GMDSS Communication Functions and Proper Availability (MSC.1/Circ.1389) – Application software and firmware updates required to meet changes in IMO and ITU regulatory requirements (possibly before the radio survey on January 1, 2024)