Where does the air defense alarm sound pass? Everywhere can be heard. Is it a lot of rooftops loaded with sirens?
In the past is the configuration of each alarm configuration and special communications equipment control, now with the development of science and technology, all controlled by the control center.
The alarm is usually installed at the top of a high-rise building, or installed in the city's small high ground, radio, communication tower top.
Once something happens, by the commander of the command, the control staff thumb gently press, the city's air raid alarm will be sounded at the same time.
Air defense warning by the Office of the Civil Air Defense (People's Air Defense Office) combined with the region's population distribution, scientific and rational allocation and monitoring.
