How do alarm system glass break detectors work?

Glass break detectors look for the sound of glass breaking. They are most effective in areas where larger panes of glass can easily be broken to gain entry to a home. They are effective on glass that is at least one square foot in size and no more than one-quarter of an inch thick. Most are rated to work on glass about 15’ to 20’ from the sensor, so a single sensor can potentially cover an entire room. However, glass break detectors can be susceptible to false alarms. We often see mail slots causing false alarms on glass break detectors as the thud (of mail hitting the floor) with the clank (of the mail slot closing) resembles the acoustic pattern the glass break detector is looking for.

All equipment and monitoring are Underwriters Laboratories (UL) Listed, meaning that they have passed a rigorous audit by an independent third-party.