1 Scope

1.1 This Standard applies to visual signaling devices intended for indoor and/or outdoor installation:

1. 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.

2. 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.

Summary of Topics

The following revisions are being issued for the Fifth Edition of ANSI/UL 1638, the Standard for Visible Signaling Devices for Fire Alarm and Signaling Systems, Including Accessories:

1. Addition of Visual Signal Pulse Width Marking, and Clarifications regarding Abnormal Operation and Burnout Test, and Mechanical Strength Tests for Enclosures

2. Reference Document Changes and Editorial Corrections