47 CFR 80.453 - Scope of communications.
Public coast stations provide ship/shore radiotelephone and radiotelegraph services.
(a) Public coast stations are authorized to communicate:
(1) With any ship or aircraft station operating in the maritime mobile service, for the transmission or reception of safety communication;
(2) With any land station to exchange safety communications to or from a ship or aircraft station;
(3) With Government and non-Government ship and aircraft stations to exchange public correspondence;
(4) With units on land in accordance with § 80.123.
(b) Public coast stations are authorized to communicate with a designated station at a remote fixed location where other communication facilities are not available.
(c) Public coast stations are authorized to transmit meteorological and navigational information of benefit to mariners.
(d) Each public coast telegraphy station is authorized to communicate with other public coast telegraphy stations to exchange message traffic destined to or originated at mobile stations:
(1) To exchange operating signals, brief service messages or safety communication;
(2) To exchange message traffic destined for a mobile station when the coast station initially concerned is unable to communicate directly with the mobile station;
(3) In the Great Lakes region, to exchange message traffic originated at a mobile station when the use of available point-to-point communication facilities would delay the delivery of such message traffic;
(4) Utilization of radiotelegraphy must not incur additional charges or replace available point-to-point communication facilities;
(5) Only authorized working frequencies within the band 415 kHz to 5000 kHz must be employed for communications between coast stations;
(6) Harmful interference must not be caused to communication between mobile stations and coast stations or between mobile stations.