UL 499:14ED 2014-11

FOREWORD
INTRODUCTION
1. Scope
1A. General
2. Components
3. Units of Measurement
CONSTRUCTION
4. General
5. Frame and Enclosure
6. Assembly
7. Stability
8. Corrosion Protection
9. Supply Connections
10. Current-Carrying Parts
11. Internal Wiring
12. Heating Elements
13. Electrical Insulation
14. Thermal Insulation
15. Motors
16. Overcurrent Protection of Conductors and Heating
     Elements
17. Motor-Running Overload Protection
18. Motor and Power-Transformer Short-Circuit and Ground-
     Fault Protection
19. General (Short-Circuit and Ground-Fault) Overcurrent
     Protection
20. Thermal Cutoffs
21. Lampholders
22. Switches
23. Automatic Controls and Control Circuits
24. Spacings
25. Grounding
26. Pressure Vessels and Parts Subject to Pressure
27. Protection Against Injury to Persons
PERFORMANCE
28. General
29. Power Input Test
30. Leakage Current Test
31. Normal Temperature Test
32. Test of Insulation Resistance and Leakage Current
     as a Result of Moisture
33. Dielectric Voltage-Withstand Test
34. Mechanical Endurance Test
34A. Resistance to Impact
35. Overflow Test
36. Abnormal Operation Test
37. Testing of Component Switches and Control Devices
38. Strain Relief Test
38A. Test for Permanence of Cord Tag for Outdoor-Use
     Heating Appliances with Power-Supply Cords Less than
     6 Feet (1.8 m)
MANUFACTURING AND PRODUCTION-LINE TESTS
39. Production-Line Dielectric Voltage-Withstand Test
39A. Polarization and Grounding Continuity Tests
RATINGS
40. Details
MARKING
41. Details
42. Instructions
ELECTRODE-TYPE HEATING APPLIANCES
43. Scope
44. General
45. Construction
46. Operation Test
47. Vaporizer-Operation Test
48. Leakage Current Test
49. Disassembly and Reassembly Test
50. Markings
51. Operating Instructions
52. Label Adhesion Test
THERMOSTAT OVERRIDE UNITS
53. General
54. Temperature Test
55. Overload Tests
APPENDIX A
Standards for Components

This revision of ANSI/UL 499 dated October 22, 2021 includes the following changes in requirements: – PTC Heater Endurance Cycles for Glue Guns; 6.2.6.2 – UL 746C Enclosures; 7.6A, 7.6B and Section 49A – Supply Cord Length of Instantaneous Water Heaters; Table 12.1 – Overcurrent Protection; 19.6 and 54.5 – Electronic Media Instructions; 54.6 and 54.7 – Addition of IEC 62471 for Ultraviolet (UV) Radiation Evaluation; 91.3.1.1 and 91.4.1.2 – Addition of UL 969A as a Replacement to Existing Permanency of Marking Requirements for Cord Tags; Section 46, 62.9, 64.1 – 64.7 and Table 64.1.

1.1 These requirements cover heating appliances rated at 600 V or less for use in unclassified locations in accordance with the National Electrical Code (NEC), ANSI/NFPA 70.