When security officers use two-way radios, they follow a protocol to ensure effective communication. A “radio check” is used to confirm that the radio is working correctly and that the signal is clear to others on the same frequency. To indicate the completion of a task, a security officer may say, “Security Officer 1 to Security Officer 2, I have finished inspecting the premises. Over.” The term “over” signifies that the speaker has finished speaking and is awaiting a response. Similarly, the term “out” is used to indicate the end of a conversation or transmission with no further response expected.

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