UL 681

1.1 These requirements provide criteria for the installation of protective wiring and devices for burglar alarm systems covering premises, stockrooms, closed areas, safes, vaults, night depositories, automated teller machines, and other security containers. The amount of alarm protection installed in a system is designated as extent of protection.

1.2 Burglar-alarm systems are classified by type of system. The types of systems covered by these requirements include central station, mercantile, bank, proprietary, and national industrial security systems. Requirements for residential burglar systems are covered in the Standard for Installation and Classification of Residential Burglar Alarm Systems, UL 1641.

1.3 These requirements also cover the installation of holdup alarm initiating devices used to send holdup or duress signals to an off premises location.

1.4 These systems employ Class 2 remote-control and signal circuits as defined by Article 725 of the National Electrical Code, ANSI/NFPA 70.