# The Wireless Telegraphy Apparatus (Citizens' Band European Users) (Exemption) Regulations 1989, Paragraph 1


A relevant CB station may be used for sending and receiving only–
(a) messages in plain speech; and
(b) signals of–
(i) less than 2.5 seconds in length, which are intended to call up any other relevant CB station; and
(ii) less than 1 second in length, which are intended to identify, or mark the end of a message sent by, any relevant CB station.

---
Source: https://www.legislation.gov.uk/uksi/1989/943/schedule/2/paragraph/1 (the official version)
Page: https://openlegislation.uk/wireless-telegraphy-apparatus-citizens-band-european-users-exemption-regulations-1989/schedule-2/paragraph-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.