People who currently work or previously worked in radio broadcasting, what is SUPPOSED to happen when dead air takes place?

Is the on-air personality (DJ, anchor, commentator, etc.) responsible for jumping in and ad-libbing?

Is the program director, producer, board operator, engineer, etc. expected to correct it?

In today’s technology-rich and human absent climate, is some type of machination installed to recognize and then rectify the problem?



  I pose this question because from what little I know of the industry, dead air is its equivalent to an airliner losing all engine power at high altitude or a cruise ship running aground or a nude shot suddenly appears on a TV screen.  A local radio station has had about three such dead air incidents over the past ten days, the longest one of them lasted about three or four minutes. It seemed as if someone was asleep at the switch, as if no one was paying attention. 

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