CAN/ULC S525:2023

Scope 1.1 This standard applies to electrically operated bells, sirens, horns, and similar audible signaling devices, rated at 300 V or less, for fire alarm and signaling systems and intended for indoor and/or outdoor installation: a) In Canada only: in accordance with CSA C22.1, Canadian Electrical Code, Part I, Safety Standard for Electrical Installations; and with ULC-S524, Standard for Installation of Fire Alarm Systems; and b) In the United States only: in accordance with the National Electrical Code, NFPA 70, and the National Fire Alarm and Signaling Code, NFPA 72. 1.2 This standard applies to audible signaling devices for use in ordinary (non-hazardous or noncorrosive) locations. 1.3 This standard also applies to protective covers and accessories used with audible signals. 1.4 This standard does not apply to door bells, buzzers and chimes used in household and similar applications and intended for operation on Class 2 signal circuits as defined in: a) In Canada only: CSA C22.1, Canadian Electrical Code, Part I, Safety Standard for Electrical Installations; and b) In the United States only: the National Electrical Code, NFPA 70. 1.5 Audible signaling devices for use in hazardous or corrosive locations shall comply with the requirements of this Standard and the applicable requirements of: a) In Canada only: CSA C22.1, Canadian Electrical Code, Part I, Safety Standard for Electrical Installations, with respect to the hazard or category classification; and b) In the United States only: the National Electrical Code, NFPA 70. 1.6 A supplementary visual signal incorporated as part of an audible signaling device which is intended for fire alarm application shall comply with the requirements of this Standard and the applicable requirements of the Standard for Visible Signaling Devices for Fire Alarm and Signaling Systems, Including Accessories, ULC 526 and UL 1638.