UL 1971:3ED 2002-11-29

Foreword
Introduction
1 Scope
2 General
3 Glossary
4 Instructions and drawings
Construction
5 Enclosures
6 Covers
7 Ventilating openings
8 Corrosion protection
9 Insulating materials
10 Mounting of parts
11 Operating mechanisms
12 Field-wiring connections - permanently connected
     products
13 Field-wiring connections - cord connected products
14 Polarization
15 Current-carrying parts
16 Internal wiring
17 Interconnecting cords and cables
18 External circuit connections
19 Printed-circuit boards
20 Motor overcurrent protection
21 Grounding for products connected to the branch
     circuit
22 Class 2 power units
23 Spacings
24 Servicing protection
Performance
25 General
26 Normal operation and electrical supervision tests
27 Signal strength and format test
28 Electrical measurements
29 Variable voltage operation test
30 Component temperature test
31 Variable ambient tests
32 Overload test
33 Endurance test
34 Transient tests
35 Vibration test
36 Electric shock current test
37 Leakage current test
38 Dielectric voltage-withstand test
39 Component failure test
40 Abnormal operation and burnout test
41 Drop test
42 Impact test
43 Crush test
44 Strain relief test
45 Indoor corrosion test
46 Special terminal assemblies tests
Installation and operating instructions
47 General
Markings
48 General
49 Permanence of marking
Appendix
A Standards for components

This revision to ANSI/UL 1971 includes Revision to the Signal Strength and Format Test to Address LED Strobes.

1.1 These requirements cover emergency-signaling devices for the hearing impaired.