Because UL is a well-known testing laboratory that also develops standards and test procedures, people have a misconception that a UL standard is exclusively tested and certified by UL. This is not the case. While UL and other organizations (CSA, NSF, etc.) are authorized to write standards, the process is done in collaboration with other vested parties such as other Nationally Recognized Testing Laboratories (NRTLs, like Intertek), key industry players (like manufacturers) and governing officials.

When it comes to certification testing to North American product safety standards, EPCO’s products are not limited only to the UL Listed Mark. The ETL Listed Mark, issued by the ETL SEMKO division of Intertek, is equally recognized and accepted by manufacturers, retailers and distributors. EPCO products that have been independently tested by a NRTL and met the minimum requirements of widely accepted product safety standards earn the ETL certification. In addition, EPCO has agreed to periodic follow-up inspections to verify continued compliance.

The NRTL program is part of the Occupational Safety and Health Administration’s (OSHA) directive to ensure products are safe for use in the U.S. workplace. It recognizes the capabilities of private-sector organizations like EPCO to determine whether a specific product meets safety standards developed by the American National Standards Institute (ANSI), Underwriters Laboratories (UL), and others. As an OSHA-recognized NRTL, Intertek has the authority to provide independent evaluation, product safety testing and certification for electrically operated or gas- or oil-fired products, and include those products that successfully complete testing in their Directory of Listed Products. This compilation of more than 40,000 products is published annually, and is also available online at

In conclusion, the ETL mark indicates the product has been tested by Intertek, found in compliance with accepted national standards, and meets the minimal requirements required for sale and/or distribution.

Engineered Products Company Inc. (EPCO) is the premier brand supplier of specialty products to electrical distributors and contractors. Headquartered in Minnetonka, MN (a suburb west of Minneapolis), EPCO has supported the electrical industry since 1976. EPCO supplies a broad range of standard and unique consumables for commercial, industrial, residential and agriculture buildings.