NCC.OP.160 Use of headset

(a) Each flight crew member required to be on duty in the flight crew compartment shall wear a headset with boom microphone or equivalent. The headset shall be used as the primary device for voice communications with ATS:

(1)  when on the ground:

(i)  when receiving the ATC departure clearance via voice communication; and

(ii)  when engines are running;

(2)  when in flight:

(i)  below transition altitude; or

(ii)  10000 ft, whichever is higher;

 and

(3)  whenever deemed necessary by the pilot in command.

(b) In the conditions of (a), the boom microphone or equivalent shall be in a position that permits its use for two-way radio communications.