1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULUNDERWRITERS LABORATORIES INC. CERTIFICATION REQUIREMENT DECISIONThis Certification Requirement Decision is prepared by UL LLC. It is normative for the applicable ULProduct Certification Program(
2、s); however, it is currently not part of the UL Standard(s) referencedbelow.Product Category (CCN): KRMXStandard Number: UL 858Standard Title: Standard for Household Electric RangesEdition Date: November 7, 2014Edition Number: 16Section / Paragraph Reference: 59.7Subject: Thermal aging testDECISION:
3、(NEW)59.7 Thermal aging59.7.1 General59.7.1.1 A polymeric material shall be resistant to thermal degradation at the maximum temperature towhich it is exposed during normal use of the appliance.59.7.2 Thermal aging test59.7.2.1 Three specimens of a polymeric part shall be tested as specified in Claus
4、e 59.7.2.2. As a resultof the test, a part shall comply with the following:a) spacings shall not be reduced to less than those specified in Table 26.1,b) current-carrying parts or internal wiring shall not be exposed, as determined in accordancewith Sections 6.2 and 10,c) a condition shall not be pr
5、oduced that could increase the risk of fire, electric shock, or injuryto persons (see 6.2), andd) a part exposed to liquids shall not crack or leak.59.7.2.2 The specimens shall be placed in an air-circulating oven for 1 000 h at the temperature specifiedin Table 59.7. The parts shall be removed from
6、 the oven, cooled to room temperature, and examined todetermine compliance with the requirements in Clause 59.7.2.1.59.7.2.3 A polymeric part shall be considered to comply with the requirements in Clause 59.7.1.1 if thematerial has a temperature index, based on historical data or a long-term thermal
7、 aging program thatindicates its acceptability for use at the temperature involved.59.7.2.4 A polymeric part shall be considered to comply with the requirements in Clause 59.7.1.1 if themaximum temperature to which the material is exposed during normal use of the appliance does notexceed 50C (122 F)
8、.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTable 59.7Temperatures for oven conditioning(See Clause 59.7.2.2.)Maximum operating temperature of polymeric enclosurepart, COven temperature,C (F)50 75 85 (185)75 85 95 (203)85 95 105 (221)RATI
9、ONALE FOR DECISION:A polymeric material shall be resistant to thermal degradation at the maximum temperature to which it isexposed during normal use of the appliance. The Thermal aging test is allowed as an alternative to theLong Term Aging program for a material per UL 746C. The Thermal aging test
10、has already been adoptedand utilized across other Major Appliance Standards, such as UL 749, UL 2157 and UL 2158.Copyright 2017 UL LLCUL LLC, in performing its functions in accordance with its objectives, does not guarantee or warrant thecorrectness of Certification Requirement Decisions it may issu
11、e or that they will be recognized or adoptedby anyone. Certification Requirement Decisions are the opinion of UL LLC. in practically applying therequirements of the standard. They do not represent formal interpretations of the standard underAmerican National Standards Institute (ANSI) processes. UL
12、LLC shall not be responsible to anyone forthe use of or reliance upon Certification Requirement Decisions by anyone. UL LLC shall not incur anyobligation or liability for damages, including consequential damages, arising out of or in connection withthe use or reliance upon Certification Requirement Decisions. The electronic version of the CertificationRequirement 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 858 -2-
