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Obtaining UL Certification with an existing ATR

Who may submit a product with an existing ATR?

IECEx LogoManufacturers or product developers (or their authorized agents, representatives, licensees or others) may submit an Assessment and Test Report (ATR) from another Accepted Certification Body (ACB) to UL and request UL certification based on the ATR.

As part of this submittal process, you may choose which company name (the manufacturer, agent or licensee) you would like to appear on the product and in UL's published product directories. Once selected, this name must appear on the product if it is found to comply with the applicable UL standard and if it is to bear a UL Mark.

A manufacturer located outside the U.S. is not required to make application for certification or approval through a representative that is a resident of the U.S.

At least one copy of the ATR will be required, and there may be a need to request at least one sample for consideration.

How do I begin the submittal process?

Contact UL's Hazardous Locations staff for assistance. In addition to providing at least one copy of the ATR, your submittal letter or communication should contain the following (if not already identified in the ATR):

  • Description of the product and its intended use. All models, types or product variations to be covered are to be identified, and description provide of the similarities and differences among models or types.
  • Identification of all components and materials used in the product, including: manufacturers' names, catalog numbers, sizes, ratings, etc. - along with whether they are Listed or Recognized by UL. Include the generic name, manufacturer and type designation of any polymeric material (for example, a thermoplastic material) and explain how it's used in the product.
  • Copies of wiring diagrams illustrating any electrical or electronic circuitry, design drawings, and/or photographs of the product - if you think they will help the UL engineer understand the design, construction and/or operation of your device.
  • Copies of all instruction manuals, safety tips or installation instructions that you expect to supply with the product, including any markings intended to appear on the shipping container.
  • Identification of any alternate materials, components or arrangements of parts you intend to use in the future. This will help reduce test work, time and costs later, when the alternates are used in the product.
  • Indication of the following coordinates:
    • The name of your authorized representative who will receive all UL communications, including the final report and invoices;
    • The company name and address of each factory where the product will be manufactured; and
    • The name and address of the company as you want it to be published in the appropriate UL product directory. (Note -- This should be the name of the company under which the product will be sold, and may be different than that of the actual manufacturer.)

In accordance with the National Electrical Code (NEC), ANSI/NFPA 70, products certified for use in hazardous (classified) locations must also comply with the applicable ANSI ordinary locations risk fire and electric shock requirements - in addition to the appropriate ANSI risk of explosion requirements. It should also be understood that, as in other countries that utilize both the Division and Zone area classification systems, some U.S. installation and regulatory authorities may not recognize the Zone area classification system.

Getting the product evaluation under way

Once UL has a copy of the ATR, and the information provided as noted above, UL's HazLoc engineering staff will:

  • Determine the scope of any additional evaluation to U.S. National Differences that may be necessary;
  • Provide an estimate of costs;
  • Indicate the amount of time needed to complete the investigation; and
  • Send you the necessary application forms.

At this point, if you have a specific deadline you are trying to meet, please let UL know so it can be considered when establishing a completion date for the evaluation. Once you return the signed application forms, provide any necessary preliminary deposit, and UL has received the necessary documentation and sample, UL's HazLoc engineering staff will begin the actual review of the ATR.

What you can expect after the evaluation?

Once the review of the ATR and sample is completed, the HazLoc project engineer will develop a formal report based on the ATR and sample review. This Report will also be used to develop a Follow-Up Services program and will serve as the basis of a Follow-Up Services Procedure.

The Follow-Up Services Procedure is a document that describes in detail the construction of the product tested and found to meet UL's requirements. UL's local field representatives use this as a guide when conducting their periodic examinations of UL certified products in the factory.

Before UL's engineering staff will issue your report, you must agree to participate in UL's Follow-Up Service program. You indicate your willingness to participate by signing and returning the Follow-Up Service Agreement. Typically, this document is sent a few days after the initial application forms are mailed.

If you have any questions about your certification, about the interpretation of a requirement, or about any UL decision, there is a UL appeals procedure that provides a method for your concerns to be heard by UL management - without jeopardizing your relationships with UL. Just contact our engineering staff for more details.

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