Transcription: Many domestic security systems are comprised of a number of different types of detectors. Break glass detectors are positioned near windows and detect the sound of glass breaking. Similarly, window foil detectors use a strip of metal foil across the window to detect damage to the window. Passive infrared sensors use infrared light to detect movement movement. All of these sensors feed their information into a central control unit or alarm panel which will set off the alarm bell should any of the sensors detect abnormal conditions.
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