Sec.  95.412   (CB Rule 12) What communications may be transmitted?

   (a)  You  may  use  your CB station to transmit two-way plain language
   communications. Two-way plain language communications are communications
   without codes or coded messages. Operating signals such as “ten codes” are
   not considered codes or coded messages. You may transmit two-way plain
   language communications only to other CB stations, to units of your own CB
   station or to authorized government stations on CB frequencies about—

   (1)  Your  personal or business activities or those of members of your
   immediate family living in your household;

   (2) Emergencies (see CB Rule 18,  Sec. 95.418);

   (3) Traveler assistance (see CB Rule 18,  Sec. 95.418); or

   (4) Civil defense activities in connection with official tests or drills
   conducted by, or actual emergencies announced by, the civil defense agency
   with authority over the area in which your station is located.

   (b) You may use your CB station to transmit a tone signal only when the
   signal is used to make contact or to continue communications. (Examples of
   circuits using these signals are tone operated squelch and selective calling
   circuits.) If the signal is an audible tone, it must last no longer than 15
   seconds  at  one  time.  If the signal is a subaudible tone, it may be
   transmitted continuously only as long as you are talking.

   (c) You may use your CB station to transmit one-way communications (messages
   which are not intended to establish communications between two or more
   particular  CB  stations)  only for emergency communications, traveler
   assistance, brief tests (radio checks) or voice paging.