Any changes or developments in an area, which are of interest of and is of navigational importance like new wreck, Racon or light becoming inoperational must be conveyed to maritime industry to promote safety.
There are three types of Radio Navigational Warnings:
- NAVAREA Warnings.
- Coastal Warnings.
- Local Warnings.
However, WWNWS (World-wide Navigation Warning Service) guidance and co-ordination are involved with only NAVAREA and Coastal Warnings and, of the latter, only with those Coastal Warnings which are broadcast under the internationally coordinated services using NAVTEX, or in lieu of NAVTEX, the International Safety NET service, as their principal means of transmission.
Details of all Radio Navigational Warnings systems are given in Admiralty List of Radio Signals Volume 3.