Underwriters Laboratories

Yes, the presence of a UL Listing Mark on a product or device is the only means to identify that that particular product or device is UL Listed. The Classification Mark for Classified products is also the only means of identification. At the present time, the use of the Component Recognition Mark, a mirror image of the "UR" is an optional marking on the component part itself.

UL has a Follow-Up Service program designed to check and verify that the manufacturer continues to produce products in compliance with the requirements of UL. UL's field representatives make periodic tests and/or examinations at the factory, and may from time to time, select samples from the factory, the open market or elsewhere for further determination of compliance. In addition, if a problem with a UL Listed or Classified product is reported to UL, UL typically opens up a field investigation.

UL Representatives audit a manufacturer periodically to make sure that a product continues to be manufactured the same way it was manufactured when it obtained UL certification. Audits may also include verification of required factory test programs, witnessing of tests required by the certification standard and verification that required test equipment is in compliance with the standard. Factory inspections are unannounced and are conducted on a periodic basis. The UL Representative typically checks random samples of the customer's current production against the product description (Follow-Up Service Procedure) written by the engineer who originally evaluated the product. If the product contains materials that are not readily identifiable, UL may conduct sample testing.

The general services agreement is a contract which explains the terms under which the UL Mark may be used. It also explains manufacturers' obligations to continuously monitor their production so their products continue to meet UL's requirements.

The general services agreement also describes the terms under which Follow-Up Service inspections are conducted. For example, the manufacturer agrees to allow UL personnel immediate, unannounced and unrestricted access to any part of the facility in which UL Certified products and components may be fabricated, assembled or stored.

Several factors determine FUS inspection costs. First, there is an annual file maintenance fee, with a base charge for the first file a client has with UL and a smaller fee for each additional file. For five or more files, UL sets a maximum fee.

Second, in-plant inspections are either billed at a fixed task rate or, for some product categories, at a per-label service charge. These fees vary depending on the product category and should be discussed with the FUS Label Group staff to get an estimated cost.

Third, follow-up sample fees may apply. Some clients may be subject to annual follow-up testing for their products and/or sub components. These also vary depending on the tests required.

The initial production inspection (IPI) is an inspection scheduled by UL to coincide with the first production run of UL certified products. An IPI is conducted whenever there is a new factory or a new product category is established at an existing factory. The UL Project Engineer may waive the IPI for an existing factory if the new product is in a similar category to another UL certified product already under Follow-Up Service at that facility.

During an IPI, the UL Representative performs a complete inspection of the product using the Follow-Up Service procedure, just as in any regular inspection. If the product complies with the requirements described in the FUS procedure, the UL Representative will release labels to the client to use on subsequent production. (There is no special charge for an IPI: regular FUS charges apply.)

In most respects, an IPI is like any other factory inspection. A major difference is that the UL representative schedules an IPI with the client rather than arriving unannounced. In addition, because the UL representative may not be familiar with the product and the factory, the IPI might take a bit longer than the regular inspection.

For logistical or financial reasons, a manufacturer may choose to split the manufacturing process between two or more manufacturing facilities. A typical example would be where an appliance manufacturer with multiple locations consolidates the manufacture of printed wiring boards at one location. The machinery to apply components and solder the boards is very expensive, and by consolidating the printed wiring board operation, the company can avoid having to duplicate the production equipment setup at each of his factories. The completed boards can be sent to various other locations for final assembly into finished products.

When a manufacturer splits the manufacturing process, UL must accommodate the manufacturer by similarly splitting the inspection process. The procedure describing the complete product is in place at both facilities. Special instructions to the UL representatives in the procedure explains what part of the manufacturing process takes place at each location as well as the responsibilities of the UL representative at each location. The procedure also describes an identifying mark that is applied at the first location to indicate to the UL Representative at the second location that the subassembly was produced under the split inspection program. The inspection of the subassembly is not repeated at the second location.

Although there are additional expenses to the client to maintain Follow-Up Service at multiple locations, these costs are typically less than the costs to a manufacturer of obtaining, maintaining and operating multiple manufacturing operations.

When a project is initiated, an instructional package is sent to the customer that includes information on ordering and designing labels. Information about obtaining labels follows:

TYPE R: Customers design the UL label layout and then submit it to the FUS label group for authorization. The manufacturer may use a label or a molding, stamping, etching, or silk-screening process to permanently apply the UL Mark. The UL Mark may stand alone, or it may be included as part of another marking such as a nameplate. The manufacturer may produce the label containing the UL Mark, or it may be obtained from a UL-authorized printer.

TYPE L: Customers must order the labels through their UL Label Center. UL Label Centers are located in local Follow-Up Services at Northbrook, Melville, RTP, and Santa Clara in the United States and in Canada, Hong Kong, Korea, Singapore, Taiwan, Japan and the United Kingdom. Customers may choose to use a UL-authorized printer or order standard labels which UL stocks for some products. In some cases, in-house printing at the manufacturing facility of Type L labels is authorized. Whether manufacturers order our in-stock labels, use an authorized printer, or produce them in house, they must still request them through UL's Label Center.

The Field Reports section of UL's Consumer Affairs Group receives and investigates reports of problems with UL certified products. To report a problem, please contact customer service.

If the examination discloses that the product is not in compliance with the requirements, the manufacturer is required either to correct such items or to remove the Listing Mark from the product.

You will be covered by a single follow-up program. When UL field representatives visit your facilities to countercheck products intended for the UL Mark, they will also be able to conduct the follow-up for any C-UL Marked products. The only additional charges you may incur will be based on the additional time the field representative spends at your facility to countercheck the C-UL Marked products. In many cases, no additional time will be needed.

Please visit our Global Field Services Web Site for additional information on Follow-Up Services. In addition, we have a tutorial called FUStart for helping new customers become more familiar with UL's Follow-Up Services program.