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Point of Purchase, Sign, and Exhibit - Knowledge Base

The Scoop On Underwriter's (UL) Listings

(Luminaires (UL1598), Portable Luminaires (UL153), Electric Signs (UL48), Wired Cabinets (UL65), And Commercial Displays)

Lighting is to a POP display what the band is to a parade! Well lit displays simply sell more merchandise. A properly lit display is not an accident. It is the end result of a deliberate and focused collaboration between sales, creative design, product development, engineering, estimating, purchasing, and the lighting vendor.

Sooner or later, every lighting project will face the question of whether or not to require Underwriter’s Laboratory (UL) listing of the electrical and mechanical components, especially the lighting elements, of the display. Maybe your client is more liability conscience than most and has this requirement as part of their specifications or, maybe your own company’s design philosophy demands this extra measure of quality and safety or, maybe your vendor has strongly suggested you consider it. However the question gets asked, the answer will effect the choice and construction of the electrical components and hence the timing and cost of your project. Understanding UL, and what UL listing means to you, will help you to make the right choices and a better, more competitive product.

The first concept to understand is that UL does not “approve” anything. They only “List” products. That means the product has been inspected by UL and complies with the current listing standard for such products. It also means the manufacturer allows UL to perform onsite periodic inspections of the product as it is manufactured to insure future product continues to meet these standards.

The second common misunderstanding is focus. UL’s concern is almost exclusively safety, not function or performance. A UL listing does not guarantee one product works better or performs better than another. It means only that the product has met the safety standard set by the listing requirements.

It all starts with NFPA70, The National Electrical Code (Nec): here is what the NEC has to say about the concept of “listed” and “approved”:

NEC 600.3: Every electric sign of any type, fixed or portable, shall be listed and installed in conformance with that listing unless otherwise permitted by special permission.
SPECIAL PERMISSION, NEC 100.2: Approved: The conductors and equipment required or permitted by this code shall be acceptable only if approved.

APPROVED: NEC100: Acceptable to the authority having jurisdiction.

AUTHORITY HAVING JURISDICTION (AHJ): NEC 90.4 Enforcement: The authority having jurisdiction for enforcement of code will have responsibility for making interpretations of rules, for deciding upon approval of equipment and materials and for granting the special permission contemplated in a number of rules.

LABELED: Equipment or materials to which has been attached a label, symbol, or other ID mark of an organization acceptable to the AHJ and concerned with product evaluation, that maintains periodic inspection of production of labeled equipment or materials and by whose labeling the manufacturer indicates compliance with the appropriate standards or performance in a specified manner.

LISTED: Equipment and materials included in a list published by an organization acceptable to the AHJ and concerned with product evaluation, that maintains periodic inspection of production of listed equipment or materials and whose listing states either that the equipment or material meets appropriate designated standards or has been tested and found suitable for use in a specified manner.

NEC 90.7 EXAMINATION OF EQUIPMENT FOR SAFTEY: It is the intent of this code that factory-installed internal wiring or construction of equipment need not be inspected at the time of installation of equipment, except to detect alterations or damage, if the equipment has been listed by a qualified Nationally Recognized Testing Laboratory (NRTL).

NEC 110.3(B) INSTALLATION AND USE: Listed and labeled equipment shall be used or installed in accordance with any instructions included in the listing or labeling.

Generally, listed equipment modified in the field will loose its listing. Unless the modifications have been specifically tested and evaluated by an organization acceptable to the AHJ, there is no way to determine if the modified product continues to comply with the safety requirements. Products originally tested and evaluated to allow for field modification will be marked accordingly.

Municipalities using their own inspection departments to verify compliance can permit alternative methods and materials. Municipalities with there own codes adopted by jurisdiction, take on greater responsibility and perhaps liability. A shield of protection is given by incorporating the use of listed and labeled products.

A Nationally Recognized Testing Laboratory, or NRTL, is the organization referred to previously. UL is one of the larger and perhaps the most well known NRTL in the USA. UL is charged with writing most if not all of the safety and electrical standards used in the USA. Most of UL’s standards are accepted by The American National Standards Institute (ANSI) as public national standards. The National Electrical Code (NEC or NFPA70) is another ANSI Standard.

There are many other NRTLs available to test products (ETL, CSA, SGS, TUV, etc.) What is important to understand is that all NRTLs, including UL, test to the same ANSI standards.

International Harmonization
Globalization, world markets, and facilitating trade are at the forefront of everyone’s mind. Many U.S.-based manufacturers distribute products in Europe, Asia and other international locations. Similarly, products manufactured in other countries are distributed in the United States. Therefore, these global products must comply with the requirements of multiple countries, and, specifically, multiple safety standards. As a result, many industries seek standards harmonization.

UL supports standards harmonization to minimize redundant or conflicting standards where support for such harmonization exists. Typically, international harmonization implies the adoption of an International Electrotechnical Commission (IEC) or International Organization for Standardization (ISO) standard. When support for harmonization of a standard is achieved, then an IEC-based UL standard is developed.

See the >>COMPLETE ARTICLE below for a PDF that will go into additional detail related to specific standards: UL1598 Luminaires, UL153 Portable Lamps, UL48 Signs, UL65 Wired Cabinets, and UL962 Commercial Furnishings and Displays, which Crownlite maintains.

Should you or your customer have any further questions regarding this article or any Crownlite product,
Please >> Contact Crownlite.

The Crownlite Knowledge Base is supplied as a convenience only. Crownlite assumes no responsibility or liability for: errors, omissions, misinterpretations, relevance, or the application to any purpose, for its Knowledge Base listings. We recommend the reader reconfirm all information before using it for any specific purpose.>15

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