October 8, 2018
By: Darrin Conlon, Director of Principal Engineers for Appliances, HVAC/R, and Lighting, Distinguished Member of Technical Staff
With the publication of any new edition of a safety standard, users of the standard typically have a few questions: What are the changes to the standard? How will these changes be implemented? And when are these changes effective? It is the intent of this article to answer these important questions.
Major Changes to UL 2157 - Electric Clothes Washing Machines and Extractors:
The new 4th edition of UL 2157, the Standard for Safety for Electric Clothes Washing Machines and Extractors, was published on May 28, 2018. This new edition includes 22 new and revised requirements. The major changes to this standard are as follows:
1. Liquid Spillage Test (clause 14.6)
The purpose of this test is to ensure the product is robust to the following foreseeable user actions:
- Accidental spillage of liquid (i.e. a bottle of bleach, cleaner, etc.) on top of the laundry appliance
And that the following potential failure modes are addressed:
- Electrical shock due to cleaning and/or spillage - evaluation method: current leakage
- Build-up of residue causing arc tracking of electrical components over time due to intermittent cleaning of the product - evaluation method: dielectric strength.
2. Glass Loading Door and Lid Test Requirements (clauses 16.3, 26.8, and 26.9)
A Working Group (WG) of the Laundry Technical Harmonization Committee (THC) met several times to develop a proposal for glass loading door and lid evaluation requirements. During the meetings, it was agreed that testing conducted on glass enclosures should be consistent with the testing of polymeric and metal enclosures. This work resulted in new requirements for glass doors and lids.
3. Lithium Button or Coin Cell Batteries used in Wireless Remote Controls with Household Appliances (clause 19.20)
The National Capital Poison Center (NCPC) has reported an increase in the number of incidents involving small children ingesting small lithium batteries in the "button/coin" configuration. These incidents have led to injury and death due to the generation of hydroxide when the battery is in contact with saliva, causing perforations of the esophagus or other serious physiological damage in as little as two hours. The Pediatrics article "Preventing Battery Ingestions: An Analysis of 8648 Cases" indicates 92 percent of the batteries identified with serious injury or death over the last decade were 20 mm lithium coin cells. UL 4200A, the Standard for Products Incorporating Button Cell Batteries of Lithium and Similar Technologies, was published on February 10, 2015. This new horizontal standard is intended to promote consistency in requirements for appliances that may incorporate lithium or similar button/coin cells.
UL 2157 now includes requirements that reference UL 4200A in the end product standard making UL 4200A a normative requirement.
4. Evaluation of Electronic Circuits and Controls (Supplement SD)
There is now an allowance to evaluate electronic circuits and controls in the end-use application using requirements that have been derived from UL 60335-1. These requirements were originally published as a UL Certification Requirement Decision (CRD).
5. Dedicated Receptacle Requirements (clauses 5.1.2.23, 8.2, 9.1.8, 19.9, and Table 17)
UL 2157 now includes dedicated receptacle requirements for the connection of a pedestal/drawer type washer. These new requirements address supplementary overcurrent protection, input, heating, marking, and instruction requirements.
6. Warning Marking and Instruction Related to Washing Water Resistant Clothing (clause 5.4.3)
Based on field incidents related to household users washing water resistant and water repellant type clothing that has resulted in out-of-balance washing conditions, this proposal is intended to provide a warning marking and instruction to users to prevent the risk of mechanical injury.
7. Nichrome Wire Test Revisions (clauses 14.7 and 26.6.3)
A Joint-Task Group consisting of members of AHAM, UL, and CSA met to align, revise, and clarify the nichrome wire test and polymeric material requirements that appear in several major appliance standards and are proposed for inclusion in other appliance standards. These proposed requirements are intended to align with the original intent of the AHAM standard revision proposals for UL 749, UL 858, UL 923, UL 2157, UL 2158, UL 60335-2-24, and UL 60335-2-40.
UL 2157 Implementation and Effective Date: Based on the nature of the new and revised requirements with respect to safety, action is required by all manufacturers to bring presently UL 2157 Certified products into compliance with the 4th edition of UL 2157 by the effective date of April 7, 2021.
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Major Changes to UL 2158 - Electric Clothes Dryers:
The new 5th edition of UL 2158, the Standard for Safety for Electric Clothes Dryers, was published on April 6, 2018. This new edition includes 15 new and/or revised requirements. The major changes to this standard are as follows:
1. Component Requirements (clause 21)
Appendix A was deleted, and the component requirements are now included in the body of the standard to promote consistency in their application. With respect to Clause 21.13.3.5, UL will be applying the following decision, which is documented in the UL 2158 CRD dated 2017-12-21:
“21.13.3.5 The secondary function control (Clause 17.6.2), door interlock (Clauses 17.1.2, and 17.7.1 (b) and 17.7.2),door lock (Clauses 17.7.1(a)), electronic braking means (Clause 17.7.1(b)), motor overload protection (Clause 21.7), temperature-limiting devices, combination temperature-regulating and -limiting devices, and any control relied upon for compliance with the abnormal operation testing of Clauses 16, 28.14, or 28.15 are considered and shall be tested and evaluated as protective controls.”
2. Fire Containment Test Revisions (clauses 16.6 and 16.7)
The standard now includes refinements to the Fire Containment Tests (FCT) that are intended to decrease testing variability. These new/revised requirements provide further clarity to the FCT requirements. These revisions were developed by a Working Group of the Laundry Harmonization Committee.
3. Lithium Button or Coin Cell Batteries used in Wireless Remote Controls with Household Appliances (clause 21.23)
UL 2158 now includes requirements that reference UL 4200A in the end product standard making UL 4200A a normative requirement. See additional information in Item 4 above for UL 2157.
4. Clothes Dryer Surface Temperature (clause 10.10 and Table 3)
Advanced research into temperature limits for touchable surfaces as well as further consideration for children and vulnerable people have caused CENELEC to adopt and the International Electro-technical Commission (IEC) to propose new surface temperature limits. We reference the work conducted by the IEC TC 61 MT 4 on Surface Temperatures and IEC Guide 117. Furthermore, gas clothes dryers have surface temperature requirements while some standards for electric clothes dryers do not. To bring greater harmonization of the standards, UL 2158 now includes surface temperature requirements.
5. Dedicated Receptacle Requirements (clauses 6.1.2.36, 9.2, 10.1.7, 21.10)
UL 2158 presently allows stacked clothes dryers to have a dedicated receptacle for the connection of a clothes washer. However, additional requirements have been added to address the use of a dedicated receptacle. These new requirements address supplementary overcurrent protection, input, heating, marking and instruction requirements.
6. Dryer Exhaust Duct Power Ventilator Installation Warning Instruction (clause 6.2.3.9)
The installation of a dryer exhaust duct power ventilator may affect a dryer's ability to comply with the UL 2158 fire containment tests due to the likelihood of greater airflow through the dryer or continued airflow after the internal dryer blower ceases to operate. This may result in greater intensity fires that spread from the clothes dryer to the building structure. The installation instruction requirements for clothes dryers have been revised to add a warning about the use of dryer exhaust duct power ventilators on household clothes dryers.
7. Nichrome Wire Test Revisions (clause 16.8)
A Joint-Task Group consisting of members of AHAM, UL, and CSA met to align, revise, and clarify the nichrome wire test and polymeric material requirements that appear in several major appliance standards and are proposed for inclusion in other appliance standards. These proposed requirements are intended to align with the original intent of the AHAM standard revision proposals for UL 749, UL 858, UL 923, UL 2157, UL 2158, UL 60335-2-24, and UL 60335-2-40.
UL 2158 Implementation and Effective Date: Similar to UL 2157, based on the nature of the new and revised requirements with respect to safety, action is required by all manufacturers to bring current UL 2158 Certified products into compliance with the 5th edition of UL 2158 by the effective date of October 7, 2021 (this is similar to that done for an industry file review).
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The full Summary of Requirements for UL 2157 and UL 2158 can be found here
After clicking on the above link, you can use the “Effective Date Information & Summary of Requirements” section on the left-hand side of the webpage to search by standard number to locate the applicable documents.
If you have questions related to the above, desire training related to these new editions of UL 2157 and UL 2158, or would like to open a Preliminary Investigation project to learn more about these changes and how they affect your UL Certified laundry appliances, please contact Darrin Conlon.