Overview
Dead air is an unintended period of silence that interrupts a broadcast during which no audio or video program material is transmitted.
Radio and television
Dead air occurs in radio broadcasting when no audio program is transmitted for an extended period of time, usually more than a few seconds. In television broadcasting, the term denotes the absence of both audio and video program material. However, a carrier wave is still transmitting. In radio, the result is silence, and in television, the result is a silent black or gray screen.
Television directors may use the command "fade to black" or "to black" to indicate a momentary transition to a completely black image. However, the term "dead air" is most often used in cases where program material comes to an unexpected halt, either through operator error or technical malfunction. Among professional broadcasters, dead air is considered one of the worst things that can occur. Moreover, dead air may impact advertising revenue if it affects the airplay of paid commercials.
The term "dead air" does not refer to a broadcast transmitter that is intentionally shut down, i.e. "closed", "signed off" or "off the air", by a control operator. Such a broadcast transmitter is said to have gone "dark".
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