Guidelines to Evaluating Unlisted Products

The American Council for Electrical Safety (ACES) is a collaboration that was formed by a variety of regulators responsible for ensuring the safety of electrical products sold in the United States. The council is sponsored by the American Council of Independent Laboratories (ACIL). Members of ACES include chief electrical inspectors, accredited laboratories, government agencies involved with regulation of electrical products, devices or installations, and representatives from organizations involved in regulation, such as IAEI. Membership is limited to such groups. The purpose of the group is to provide a forum twice a year for all parties involved in product testing, certification, approval and recognition, in which they can discuss issues relating to electrical safety.

Electrical products, both those made in the United States and those imported, are sources of major concern to electrical inspectors as they make decisions affecting the safety of persons and property. The concern is justified; due to the pressure to maintain competitiveness, some manufacturers may perceive a need to reduce product costs by sacrificing quality and safety. Also, some specialty manufacturers build one-of-a-kind products without completely understanding the requirements for electrical or fire safety. In addition, new requirements are continually added to standards, based on incidents that occur in the United States revealing previously unrecognized hazards. A manufacturer may or may not have the facility to keep up with these standards.

Photo 1


Certification laboratories, however, must keep up with these standards in order to maintain their governmental and other official recognitions. This characteristic of listing laboratories ensures that a properly listed product does comply with the current edition of the applicable standard.

An electrical inspector must rely on some credible source when inspecting installations. Inspectors must know requirements in the local, state or national codes. To perform the in-depth inspections necessary to determine that a product complies with an applicable standard and the installation meets requirements in the National Electrical Code is a major time-consuming effort. It must be performed by someone who is an expert in both the product category and the National Electrical Code. Additionally, most products call for the application of at least one standard that requires some tests be conducted in a laboratory to determine that the product complies with the standard and is safe.

When the product is listed the inspector can usually rely on the listing of the product to determine that the product complies with the correct, applicable standard. Also, the laboratory is accredited by OSHA and often other accrediting bodies. Accreditation covers the various standards that apply to the thousands of different electrical products.

Some laboratories are only accredited to evaluate compliance with a few standards while others may be accredited to certify products against hundreds of standards.

Photo 2. Machines used in industrial applications

During the accreditation process a laboratory must prove to experts that the laboratory has the knowledge and equipment to test to the standard. Accreditation is a continuous process with reviews of the laboratory performed every few years. Accreditation of a laboratory usually takes a team of two to three experts from two to five days per visit. This gives the inspector the assurance that the product—if installed within the parameters of the listing instructions—meets all relevant safety standards.

However, when a product is manufactured in the field, or a product’s manufacturer was never reviewed by a certification agency, or a product is modified, it is, or has become, by definition an unlisted product. It often is the case that a product’s manufacturer never is reviewed by a U.S. certification agency when the product is imported or its manufacturer is small or custom. In any of these cases, the inspector has to either become the accrediting agency, providing his own inspections and approvals, or else accept only laboratories that already are nationally accredited. This has been a dilemma for inspectors, especially the ones that realized the significance of recognizing organizations to perform these services. If an unlisted product goes undetected and it causes a hazard, the electrical inspector could be held accountable. This is an unreasonable burden to be placed on an inspector. Also, if the hazard is in a workplace and results in an OSHA investigation the employer can be fined from $7,000 to $70,000 for each violation.

Photo 3. Typical industrial control panels

The American Council for Electrical Safety (ACES)’s development of a document that an inspection authority can utilize in selecting organizations that can perform these inspections is timely. Jurisdictions faced with the responsibility to accept organizations for performing field inspections of products are seeking help. Some jurisdictions are attempting to write their own requirements, or just feel forced to accept people who are claiming to have the ability to perform product evaluations competently. The responsibility is really enormous, given the liability associated with allowing someone who may be unqualified to perform these inspections. This document is titled “Recommended Practice for Unlisted Equipment.”

Inspection agencies that institute this procedure in recognizing organizations for performing field inspections and labeling take a lot of responsibility off themselves and the jurisdictions where they work. The safest and most responsible procedure for an authority having jurisdiction is to adopt this procedure, “Recommended Practices for Unlisted Equipment.”

Meanwhile, additional help is on the way. Right now, the only laboratories in which everyone can have full confidence are the nationally recognized testing laboratories (NRTLs) that the Department of Labor has authorized to list products for workplace use. For several years, ACES has been working to develop a means of judging whether other, perhaps local labs are qualified to perform just those field evaluations of unlisted equipment that are of such concern. After all, on the one hand, if an incompetent engineer attempts to apply recommended practices, they may not be of any great use, and on the other, if a NRTL sends someone out one would hope the “Recommended Practices. . .” document would be superfluous. A draft of “Recommended Competence Guidelines for Third Party Field Evaluation Organizations” is being circulated for public comment as you read this. It should complement “Recommended Practice for Unlisted Equipment” nicely.

For more information concerning ACES or these guidelines contact ACIL at 202/887-5872, or get in touch with Leonard Frier, chairman of ACES, at MET Laboratories, Inc. by phone at 410/354-3300 or email

Len Frier
Len Frier is a registered professional electrical engineer in the state of Maryland. He founded MET Laboratories in 1959. He initiated the Nationally Recognized Testing Laboratory Program at OSHA in 1988, and is charter member of the National Electrical Testing Association (NETA). He is former chairman of the ANSI Z34 committee on "Third Party Certification," chairman of the American Council on Electrical Safety (ACES), member of the ANSI Accreditation Committee, and the American Council of Independent Laboratories (ACIL). Presently, he is director at MET Laboratories, Inc. and is active in government affairs relating to US Certifications of electrical products.