§  90.403   General operating requirements.

   (a) Licensees of radio stations in the private land mobile radio
   services shall be directly responsible for the proper operation and use
   of each transmitter for which they are licensed. In this connection,
   licensees shall exercise such direction and control as is necessary to
   assure that all authorized facilities are employed:

   (1) Only for permissible purposes;

   (2) Only in a permissible manner; and

   (3) Only by persons with authority to use and operate such equipment.

   (b) In carrying out their responsibilities under § 90.403(a), licensees
   shall be bound by the provisions of the Communications Act of 1934, as
   amended, and by the rules and regulations of the Commission governing
   the radio service in which their facilities are licensed; and licensees
   may not, through written or oral agreements or otherwise, relieve
   themselves of any duty or obligation imposed upon them, by law, as
   licensees.

   (c) Except for stations that have been granted exclusive channels under
   this part and that are classified as commercial mobile radio service
   providers pursuant to part 20 of this chapter, each licensee must
   restrict all transmissions to the minimum practical transmission time
   and must employ an efficient operating procedure designed to maximize
   the utilization of the spectrum.

   (d) Communications involving the imminent safety-of-life or property
   are to be afforded priority by all licensees.

   (e) Licensees shall take reasonable precautions to avoid causing
   harmful interference. This includes monitoring the transmitting
   frequency for communications in progress and such other measures as may
   be necessary to minimize the potential for causing interference.

   (f) Stations licensed in this part shall not continuously radiate an
   unmodulated carrier except where required for tests as permitted in
   § 90.405, except where specifically permitted by this part, where
   specifically authorized in the station authorization, or on an as
   needed basis in the Radiolocation Radio Service.

   (g) The radiations of the transmitter shall be suspended immediately
   upon detection or notification of a deviation from the technical
   requirements of the station authorization and until such deviation is
   corrected. For transmissions concerning the imminent safety-of-life or
   property, the transmissions shall be suspended as soon as the emergency
   is terminated.

   [ 43 FR 54791 , Nov. 22, 1978;  44 FR 32220 , June 5, 1979, as amended at
    59 FR 59965 , Nov. 21, 1994]