Effective May 6, 2018

Standard Information
Standard Number:
UL 2021
Standard Name:
Standard for Safety for Fixed and Location-Dedicated Electric Room Heaters
Standard Edition and Issue Date:
4th Edition Dated September 30, 2015
Date of Revision:
4th Edition Dated September 30, 2015
Date of Previous Revisions to Standard:
Effective Date of New/Revised Requirements

Effective Date (see Schedule below): May 6, 2018

Impact, Overview, Fees and Action Required

Impact Statement: A review of all Listing Reports is necessary to determine which products comply with new/revised requirements and which products will require re-evaluation. NOTE: Effective immediately, this revised standard will be exclusively used for evaluation of new products unless the Applicant requests in writing that current requirements be used along with their understanding that their listings will be withdrawn on Effective Date noted above, unless the product is found to comply with new/revised requirements.

Overview of Changes: Changes to Requirements for Wall-mounted Heaters Located Near Ceiling Height. Specific details of new/revised requirements are found in table below.

If the applicable requirements noted in the table are not described in your report(s), these requirements will need to be confirmed as met and added to your report(s) such as markings, instructions, test results, etc. (as required).

Schedule: So that shipping of products with Listing Marks will not be interrupted, an approximate schedule has been established to ensure Listing Reports are found compliant by Effective Date:

  • October 6, 2017 = 8 Month Report Review – Intertek will review all Reports. Update if compliance is verified or issue Findings Letter/Quote for any re-evaluations needed
  • December 6, 2017 = 6 Month Quote Cut-off – Quotes returned for necessary re-evaluations
  • April 6, 2018 = 30 Day Warning – Client advised of all non-compliant Reports to be Suspended
  • May 6, 2018 = Effective Date – ATM Suspended for all non-compliant Reports

Fees: An initial review of Listing Report (s) will be covered by a direct billing project and will be invoiced at not more than $1000 per report.

Client Action Required:

Information – To assist our Engineer with review of your Listing Reports, please submit technical information in response to the new/revised paragraphs noted in the attached or explain why these new/revised requirements do not apply to your product (s).

Current Listings Not Active? – Please immediately identify any current Listing Reports or products that are no longer active and should be removed from our records. We will do this at no charge as long as Intertek is notified in writing prior to the review of your reports.

Description of New/Revised Technical Requirements
38 Continuous Operation Test
38.1 A permanently connected wall-mounted air heater and a heater intended to be mounted to an outlet box in a wall are to be supported in the intended manner on the black-painted surface of a wall consisting of 3/8-inch-thick (9.5 mm) plywood fastened to both shorter sides of nominal 2- by 4-inch (38- by 89-mm) vertical wooden studs on 16-inch (406 mm) centers. Two or more such walls are to be fastened together to form a 90-degree angle, and the height and length of the walls are to be such that they extend not less than 2 feet (610 mm) beyond the physical limits of the heater. A ceiling surface is to be added consisting of 3/8-inch (9.5-mm) plywood. The heater is to be located as close to the sides of the wall angle as its construction will permit, and it is to be placed relative to the walls that maximum heating will occur on the latter; except that it may be spaced away from the sides of the wall angle to prevent the attainment of temperature rises of more than 65°C (117°F) thereon if the heater is marked as described in 59.22.
38.2 Heaters intended to be mounted on the wall at or near ceiling height shall be tested in the corner as close to the side walls and ceiling as construction will permit unless it is marked in accordance with 59.22.
38.3 A cord-connected wall mounted air heater is to be installed in the same manner as described in 38.1 except no consideration is to be given to the clearance marking described in 59.22.

CUSTOMERS PLEASE NOTE: This Table and column "Verdict" can be used in determining how your current or future production is or will be in compliance with new/revised requirements.

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