1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULUNDERWRITERS LABORATORIES INC. CERTIFICATION REQUIREMENT DECISIONThis Certification Requirement Decision is prepared and published by Underwriters Laboratories Inc.(UL). It is normative for the a
2、pplicable UL Product Certification Program(s); however, it is currently notpart of the UL Standard(s) referenced below.Product Category (CCN): IFUXStandard Number: UL 844Standard Title: Standard for Luminaires for Use in Hazardous (Classified) LocationsEdition Date: June 29, 2012Edition Number: 13Se
3、ction / Paragraph Reference: 37Subject:DECISION:37 Non-Metallic Enclosure Tests Class II37.1 An enclosure made of a non-metallic material shall be subjected to tests to determine that it isequivalent to comparable metal enclosures that have been found suitable for use in Class II hazardouslocations.
4、37.2 A non-metallic enclosure shall comply with the requirements in 35.3.3, Accelerated Aging Tests,35.4, Tests for Accumulation of Static Electricity, and the Standard for Enclosures for ElectricalEquipment, Non-Environmental Considerations, UL 50.37.3 A non-metallic enclosure shall be such that th
5、e minimum widths of joints or shaft openings do notdecrease nor the maximum clearances increase beyond those specified, under all conditions of use. Inaddition, tests shall show that no other adverse effects are expected to occur such as loosening of parts,reduction in electrical spacings, ignition
6、of the material from an electrical arc, or accumulation ofelectrostatic charges.37.4 Consideration is to be given to all variations in chemical composition, color percentage mix, ormolecular weight.37.5 Prior to the test of SA5.3, diffusers, globes, refractors, lenses and similar optics that are mad
7、e frompolymeric material shall be permitted to be subjected to short term-aging using the formula found in SA5.3when all of the following applies:a) The polymeric material which forms the optic portion must be a UL Recognized material withan established RTI value, and used within this rating.b) The
8、polymeric material which forms the optic portion forms a part of a gasketed metal topolymeric joint.c) The joint is not intended to be a serviceable joint.d) Air temperature is conducted measuring the lens internal service temperature, in addition toall gasket internal service temperatures, ande) Th
9、e maximum internal service temperature is used in the aging formula in SA5.3.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULRATIONALE FOR DECISION:The use temperature for certain polymeric materials used to form diffusers, globes, refractors,
10、 lenses andsimilar optics can be such that the long-term aging formula will result in a test time that is of animpractically long duration. This alternative short-term aging is congruent with the required aging ofgaskets prior to the dust penetration test for gaskets that are not located in a servic
11、eable joint.Copyright 2015 Underwriters Laboratories Inc.UL, in performing its functions in accordance with its objectives, does not guarantee or warrant thecorrectness of Certification Requirement Decisions it may issue or that they will be recognized or adoptedby anyone. Certification Requirement
12、Decisions are the opinion of Underwriters Laboratories Inc. inpractically applying the requirements of the standard. They do not represent formal interpretations of thestandard under American National Standards Institute (ANSI) processes. UL shall not be responsible toanyone for the use of or relian
13、ce upon Certification Requirement Decisions by anyone. UL shall not incurany obligation or liability for damages, including consequential damages, arising out of or in connectionwith the use or reliance upon Certification Requirement Decisions. The electronic version of theCertification Requirement Decision is the current version and previously printed copies may be outdated.This document is published as a service to ULs certification customersSTANDARD NUMBER: UL 844 -2-
