What should all interphone messages be terminated with?

Interphone messages should always be terminated with operating initials. This practice ensures accountability and traceability by clearly identifying who has sent the message. By including their initials, the sender indicates their personal responsibility for the content of the interphone communication, which is crucial in the high-stakes environment of air traffic control where clear and precise communication is essential for safety and operational efficiency.

In circumstances where messages need further clarification or follow-up, being able to trace back the communication to a specific individual helps in addressing any questions or concerns about the instructions or information conveyed. This practice not only promotes professionalism but also assists in maintaining a reliable record of exchanges among team members.