CSA or UL: Which Listing is Right for Electrical Products?

July 3, 2018
Engineers can be confused when it comes to CSA and UL markings. Here’s quick look at the markings and what they mean.

There is a widespread misconception among electrical professionals in the U.S. that the “CSA-us” marking is somehow less significant than one that reads “UL Listed.” The fact is, Underwriters Laboratories (UL) and CSA Group (CSA) are both Nationally Recognized Testing Laboratories (NRTL) that test to the same harmonized Canadian Electrical Code (CEC) and National Electrical Code (NEC) standards, making their certifications virtually interchangeable.

The presence of a CSA mark with a “US” subscript indicates CSA has tested and evaluated the product for compliance with appropriate American National Standard, and it therefore meets the requirement for being “listed” in accordance with National Fire Protection Assoc. (NFPA) standard NFPA 70, and the National Electrical Code (NEC). Whether a product carries the “UL Listed” or “CSA-us” mark, end-users in the U.S. should have complete confidence in its compliance and performance.

What is the U.S. Safety Certification Process?

In the U.S. the safe installation of electrical products is assured by conformance to NFPA 70 of the NEC. Although the NEC is not a mandatory standard, it is adopted as law in almost every state or locality in the U.S. Enforcing the NEC is delegated to the local Authority Having Jurisdiction (AHJ), such as a building inspector or fire marshal.

NEC’s Sections 90.7 and 110.3 define parameters that let independent testing labs judge the suitability of electrical equipment to appropriate American National Standards. There are several sections of the NEC that require certain types of electrical equipment be listed, including Section 410.6, which states all luminaries must be listed. There are no sections of the NEC requiring products be UL listed.

Many code experts believe the NEC intentionally left the definition of “Listed” generic to allow for competition between third-party certification bodies and prevent monopolization of the product safety certification market.

SDOs and Certification Bodies

Standards Development Organizations (SDOs) create the actual standards that electrical products are tested against to ensure safe operation. Committees developing the standards may include employees of product manufacturers and testing laboratories.

In the U.S., the American National Standards Institute (ANSI) is the authority for publishing the American National Standards for electrical products. ANSI assigned SDO status to UL to develop these standards.

Likewise, in Canada, the Standards Council of Canada granted SDO status to the CSA Group for developing Canadian National Standards, and it also recognizes UL as an accredited Certification Body which can test and list products to Canadian standards.

Although UL and CSA act as both SDOs and third-party Certification Bodies, there is no requirement for product certification to be performed by the SDO responsible for overseeing the development of the standard. Any accredited NRTL can be used by a manufacturer to evaluate a product.

UL Listed and CSA Certification Marks

There is a misconception that CSA certified products are only for use in Canada, and cannot be sold or installed in the U.S., while UL Listed products are for the United States and global use. Depending on certification, both CSA and UL products can be used locally and internationally.

CSA Group, an independent third-party agency hired by manufacturers to test and certify many types of products, was recognized in 1992 by the U.S. Occupational Safety & Health Administration as a Nationally Recognized Testing Laboratory (NRTL).

Like UL and other NRTL labs, CSA Group tests and certifies many U.S. leading brands to confirm they comply with applicable American National Standards written by ANSI, ASME, ASTM, ASFE, UL, CSA, NSF, and others. All OSHA recognized labs test using the same procedures against the same sets of standards and codes, regardless of who authored or published them. Because several laboratories have earned OSHA recognition, manufacturers have the flexibility to choose the testing partner most capable of economically meeting their timing, service, or other requirements.

For access to the broadest range of products available, it is important when writing product specifications or RFQs to allow for inclusion of all products tested and certified by any NRTL lab, as defined by OSHA 1901.7.

CSA Does Not Mean “Canada Only”

Some specifiers, installers, and purchasing agents may mistakenly believe only the lab whose company’s name appears as the SDO on a specific standard may undertake product testing against that standard. However, product manufacturers are not required to contract with the SDO, and many do not.

Publishing standards and testing products are completely different functions. Standards are available to any qualified lab selected by a manufacturer to test and certify a product before it goes to market. Moreover, all NRTLs use the same testing standards regardless of which lab performed the tests. This leveling of the playing field creates a competitive marketplace that helps manufacturers get their products to end-users faster and more economically, while still ensuring they undergo rigorous testing to American National Standards. Therefore, if the specifier in the U.S. narrows down an RFQ to only ”UL Listed” rather than include “CSA-us,” they are inadvertently eliminating excellent products from consideration and limiting the brands, models, delivery, cost, and other critical features available to them.

Ellen Helm is a manager at Appleton Lighting, Electrical Apparatus & Lighting, Emerson Automation Solutions

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