Section 220.37 - Testing radio and wireless communication equipment(a) Each radio, and all primary and redundant wireless communication equipment used under §§ 220.9 and 220.11 , shall be tested as soon as practicable to ensure that the equipment functions as intended prior to the commencement of the work assignment.(b) The test of a radio shall consist of an exchange of voice transmissions with another radio. The employee receiving the transmission shall advise the employee conducting the test of the clarity of the transmission.