UL 639

Standard for Intrusion-Detection Units

1.1 These requirements cover intrusion-detection units intended to be used in burglary-protection signaling systems. These units are intended to be used in indoor or outdoor locations to automatically indicate the presence of an intruder by actuating electrical control circuits.

1.2 An intrusion detector, as covered by these requirements, consists of one or more unit assemblies of electrical components that are designed to detect the presence, movement, sound or other activity of an intruder. Provision is made for connection to the assembly of power supply, remote control, and signal circuits by a prescribed method of wiring.

1.3 Intrusion-detection units covered by these requirements are intended to be installed in accordance with the Standard for Installation and Classification of Burglar and Holdup Alarm Systems, UL 681.


  • Edition Number: 8
  • Edition Date: 08/31/2007
  • Price Code: B
  • Type: ulstd
  • ANSI Approved: 05/15/2012
  • DOD Approved: