A glass-break sensor is an acoustic detector, usually mounted on a ceiling or wall within listening range of windows, that recognizes the specific sound frequencies produced when glass shatters and sends a signal to the alarm panel. Some models also detect the lower-frequency thump of an impact before the break, adding an extra layer of detection.
On a real property, effective range is typically limited to a room or a defined radius, so a large lobby with many windows may need multiple sensors rather than one central unit. Sensors calibrated for standard glass may under- or over-trigger on laminated, tempered, or double-pane glass with different acoustic signatures.
False alarms can come from other sharp sounds — dropped keys, jangling metal, or a slammed door — that share some acoustic characteristics with breaking glass. Like other alarm sensors, a glass-break unit only detects; it does not prevent entry once glass is broken.
In a patrol program, a glass-break alert is treated as a high-priority dispatch given its association with forced entry, sending an officer to check the specific window or door zone identified by the panel before anyone re-enters the building.
Related entries
Official sources
- [1]NIST intrusion detection systems overviewNational Institute of Standards and Technology
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