Sec. 80.330  Safety message.

    (a) The safety signal and call must be followed by the safety 
message. Where practicable, the safety message should be sent on a 
working frequency, and a suitable announcement to this effect must be 
made at the end of the call.
    (b) Except for the cases mentioned in paragraph (c) of this section, 
the safety signal when sent on the frequency 500 kHz must be transmitted 
toward the end of the first available silence period; the safety message 
must be transmitted immediately after the silence period.
    (c) Messages about meteorological warnings, of cyclones, dangerous 
ice, dangerous wrecks, or any other imminent danger to marine navigation 
must be preceded by the safety signal.
    (d) Stations hearing the safety signal must not make any 
transmission likely to interfere with the message.