UL 746A PDF

1 Scope

1.1 These requirements cover short-term test procedures to be used for the evaluation of materials used for parts intended for specific applications in electrical end products.

1.2 Together with the requirements mentioned in Supplementary Test Procedures, Section 5, these investigations provide data with respect to the physical, electrical, flammability, thermal, and other properties of the materials under consideration and are intended to provide guidance for the material manufacturer, the molder, the end-product manufacturer, safety engineers, and other interested parties.

1.3 A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire or of electric shock or injury to persons shall be evaluated using appropriate additional component and end-product requirements to maintain the level of safety as originally anticipated by the intent of this standard. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this standard does not comply with this standard. Revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard.

Summary of Topics

This revision of ANSI/UL 746A dated January 21, 2025 includes the following changes in requirements:

– New Test Method to Measure Resistivity of Partially-conductive Polymeric Materials in Accordance with ASTM D4496 in a New Section 22A.

– Clarification of Requirements for Code D in 9.9.2, 9.9.7 (new), and Table 9.1 and Table 9.2

– Removal of the HVAR Test Provided in Section 34 from UL 746A